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 symptoms, pathology, diagnosis, prognosis, treatment, etc., and 
 contains additional, special sections on mental diseases, diseases 
 of the skin, and ductless glandular diseases. 
 
 TRUMPER MEMORANDA OF TOXICOLOGY 
 
 2d Edition. Fabrikoid, $1.50 
 
 By Max Trumper, Ph. D., Formerly Lecturer on Toxicology, 
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 The author has had much hospital experience and has seen cases 
 of poisoning in their symptomatic conditions. The book is a 
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 poisoning and most recent progress in toxicology. 
 
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 thorized Translation by Wm. H. Warren, Ph.D., Professor of 
 Organic Chemistry, Clark University, Worcester. 
 
 Many new substances and methods have been included in this 
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MORRIS HUMAN ANATOMY, 8th EDITION 
 
 1164 Illustrations, 515 in Colors. Cloth, $10.00 
 
 A systematic treatise prepared by collaboration of a number of 
 anatomists and Edited by C. M. Jackson, M.S., M.D., Pro- 
 fessor and Director, Department of Anatomy, University of 
 Minnesota. 
 
 ELLIS ELEMENTS OF PATHOLOGY 
 
 95 Illustrations. Cloth, $5.00 
 
 By Aller G. Ellis, M.Sc.. M.D. Rockefeller Foundation 
 Visiting Professor of Pathology and Director of Studies, Medical 
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 time Associated Professor of Pathology, Jefferson Medical 
 College, Philadelphia. 
 
 This book has been written for beginners in pathology. A 
 special effort has been made to explain elementary principles 
 and to limit the text to the essentials. 
 
 It shows the close relation of pathology to problems of internal 
 medicine and surgery. 
 I 
 
 EDGAR- VAUX OBSTETRICS, 6th EDITION 
 
 684 Illustrations, 38 Colored Prints, 5 Colored Plates. 
 Cloth, $8.00 
 
 By J. Clifton Edgar, Revised by Norris W. Vaux, Clinical Pro- 
 fessor of Obstetrics, Jefferson Medical College and Hospital, 
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 This new Edgar- Vaux Obstetrics is a distinctly practical guide, 
 illustrated in detail by handsome engravings. The descriptive 
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 clinical manual. 
 
? 
 
COMPEND 
 
 OF 
 
 HUMAN ANATOMY 
 
COMPENDS 
 
 Each Volume, Cloth $2.00. 
 
 HUMAN ANATOMY. 8th Edition. 16 Plates, 139 
 Text Illustrations. By S. O. L. Potter, M. D. 
 Revised by D. G. Metheny, M. D. 
 
 PHYSIOLOGY. i6th Edition. 27 Illustrations. By 
 
 A. P. Brubaker, M. D. 
 
 OBSTETRICS. loth Edition. 80 Illustrations. By 
 H. G. Landis, M. D. Revised by Dr. Clifford 
 
 B. Lull, M. D. 
 
 MATERIA MEDICA, THERAPEUTICS AND PRESCRIPTION 
 WRITING. 9th Edition. Accord with U. S. 
 Phar. X. By S. O. L. Potter, M. D. Revised 
 by A. D. Bush, M. D. 
 
 GYNECOLOGY. 5th Edition. 167 Illustrations. By 
 Wm. H. Wells, M. D. Revised by W. G. Harer, 
 M. D. 
 
 DISEASES OF THE EYE AND REFRACTION. 4th Edition. 
 109 Illustrations. By G. M. Gould, M. D. and 
 W. L. Pyle, M. D. 
 
 SURGERY. Bandaging and Minor Surgery. 185 Illus- 
 trations. By Benjamin Lipshutz, M. D. 
 
 MEDICAL CHEMISTRY. 7th Edition. By Henry Leff- 
 mann, M. D. and Max Trumper, A. M. 
 
 PHARMACY. loth Edition. Based upon Remington's 
 Pharmacy, U. S. Phar. and U. S. Formulary. By 
 F. E. Stewart, M. D. Revised by H. W. 
 Youngken, M. D. 
 
 DISEASES OF THE SKIN. 7th Edition. 119 Illustra- 
 tions. By J. F. Schamberg, M. D. 
 
 GENITO-URINARY DISEASES AND SYPHILIS. 4th Edi- 
 tion. 44 Illustrations. By C. S. Hirsch, M. D. 
 
 BACTERIOLOGY. 4th Edition. 86 Illustrations. By 
 R. L. Pitfield, M. D. 
 
 P. BLAKISTON'S SON & Co. Philadelphia 
 
POTTER'S 
 
 C O M P E N D 
 
 OF 
 
 HUMAN ANATOMY 
 
 REVISED BY 
 
 D. GREGG METHENY 
 
 M. D., L. R. C. P. AND S. (EDTN.), L. F. P. S. (GLASGOW) 
 ASSOCIATE IN ANATOMY, JEFFERSON MEDICAL COLLEGE, PHILADELPHIA 
 
 EIGHTH EDITION 
 
 WITH 139 ILLUSTRATIONS; ALSO NUMEROUS TABLES AND 
 16 PLATES OF THE ARTERIES AND NERVES 
 
 
 PHILADELPHIA 
 
 P. BLAKISTON'S SON & CO., INC 
 
 1012 WALNUT STREET 
 
COPYRIGHT, 1915, BY P. BLAKISTON'S SON & Co. 
 
 PRINTED IN U. S. A. 
 BY THE MAPLE PRESS COMPANY, YORK, PA. 
 
PREFACE TO THE EIGHTH EDITION 
 
 After many years of wandering in the embryological minutiae of " trans- 
 cendental anatomy," it has at last become apparent to most teachers and 
 examiners in anatomy that the only kind of anatomy that could be of any 
 practical value to a physician or surgeon, as such, is the anatomy that 
 can be actually seen and handled. Consequently in this text, details of 
 embryology, histology, and physiology have been largely left to the text- 
 books dealing with those subjects, in order that gross human anatomy 
 might be the more thoroughly explained. 
 
 While all of the "recognized authorities" and the publications of the 
 various anatomical associations have been freely consulted, these descrip- 
 tions have been based entirely on the actual facts to be found in the human 
 body and are not dominated by any one single authority. The many new 
 discoveries and the changes in teaching methods that have been made in 
 recent years, have made it necessary to make so many additions and 
 changes in the text that the entire work had to be rewritten. Parts of 
 the nomenclature of the German Anatomical Society are now being used 
 so universally, that it became necessary to include it, in its entirety, in 
 the Latin form. However, since comparative anatomy has been almost 
 entirely ignored in the B.N.A., and as so many of its terms are not only 
 inconsistent but also evidence personality rather than broad anatomical 
 principles, it seems certain that it still requires much revision if it is to 
 endure; therefore while the B.N.A. terms are given in the Latin form, 
 only such of them as seem entitled to survival are given in the English 
 form in preference to the older regular terms. 
 
 It is confidently hoped that the student will find these descriptions 
 not only accurate and up-to-date, but intelligible as well. 
 
 D. GREGG METHENY. 
 
 4609 SPRUCE ST., PHILADELPHIA. 
 
 2.112.2, 
 
PREFACE TO THE SEVENTH EDITION 
 
 The twenty years which have elapsed since this compend was first 
 issued have brought many changes of nomenclature and description 
 into the teaching of Anatomy. The present edition has been entirely 
 re-written and brought into harmony with the latest text-books on this 
 subject. The text has been expanded wherever greater detail seemed 
 desirable, but in so doing the condensed form of statement heretofore 
 adopted has been carefully followed. The total number of illustrations 
 has been increased from 117 to 138, and many of the cuts used in former 
 editions have been replaced by newer ones. The Tables and Plates, 
 heretofore published in an appendix, have been thoroughly revised, 
 and are now placed in their natural positions in the text. These changes 
 have increased the size of the volume by 82 pages, and have made it 
 practically a new book, which the author hopes will receive a continu- 
 ance of the favor heretofore extended to the previous editions. 
 
 Originally designed for the use of the medical student in preparing 
 for the exercises of the quiz-room and for his examinations, the text is 
 confined to the essentials of each structure treated of, which are arranged 
 in such a manner as to facilitate their rapid acquirement. All super- 
 fluities of description have been studiously avoided, and only such matter 
 inserted as should be thoroughly known in order to pass a rigid examina- 
 tion on any organ or structure of the human body. The descriptions will 
 be found to closely follow Gray, though Morris, Quain, and other recog- 
 nized authorities have been freely consulted during the preparation of 
 the text. For many of the special arrangements the author is indebted 
 to the lectures of Professor W. H. Pancoast, formerly of Jefferson Medical 
 
 vii 
 
Vlll PREFACE TO THE SEVENTH EDITION 
 
 College, and to the quizzes of Dr. Henry Morris, at one time assistant 
 to the chair of Anatomy in the same school. 
 
 While striving to carry out the object of this series in furnishing the 
 medical student with a condensed manual of Anatomy, the author has 
 endeavored, from a strong appreciation of the importance of the subject, 
 to make this volume deserving of first rank among its kind; and believing 
 that a judicious condensation, which does not slight the essential features 
 of the subjects treated, cannot fail to be of benefit in any department 
 of science, he again commits this compend to the teachers and students 
 of Anatomy, in the hope that it may continue to be found worthy of a 
 place alongside the more exhaustive and exhausting text-books. 
 
 SAM'L O. L. POTTER. 
 
CONTENTS 
 
 FACE 
 
 OSTEOLOGY i 
 
 BONES OF THE TRUNK. . . . 5 
 
 VERTEBRAL COLUMN 5 
 
 THORAX 7 
 
 PELVIS 9 
 
 BONES OF THE HEAD 14 
 
 ORBITS 35 
 
 FOSSAE 37 
 
 SUTURES AND FONTANELLES 39 
 
 FORAMINA AT THE BASE OF THE SKULL 41 
 
 POINTS AT THE BASE OF THE SKULL 44 
 
 BONES OF THE UPPER EXTREMITY 44 
 
 OF THE SHOULDER 44 
 
 OF THE ARM 47 
 
 OF THE FOREARM 48 
 
 OF THE HAND 50 
 
 BONES OF THE LOWER EXTREMITY 52 
 
 OF THE THIGH 52 
 
 OF THE LEG 54 
 
 OF THE FOOT 56 
 
 ARTICULATIONS 58 
 
 ARTICULATIONS OF THE TRUNK 60 
 
 OF THE UPPER EXTREMITY .* 64 
 
 OF THE LOWER EXTREMITY 68 
 
 MUSCLES AND FASCIAE 73 
 
 MUSCLES OF THE HEAD 75 
 
 OF THE EAR 79 
 
 OF THE NECK 80 
 
 ix 
 
X CONTENTS 
 
 PAGE 
 
 OF THE LARYNX AND EPIGLOTTIS 85 
 
 OF THE BACK 86 
 
 OF THE THORAX 93 
 
 OF THE ABDOMEN 95 
 
 OF THE PELVIC OUTLET 97 
 
 OF THE PERINEUM 98 
 
 OF THE UPPER EXTREMITY 99 
 
 OF THE LOWER EXTREMITY 107 
 
 FASCIA OF THE HAND 105 
 
 LUMBO-DORSAL 90 
 
 OF THE ILIAC REGION 107 
 
 OF THE THIGH 108 
 
 OF THE FOOT 115 
 
 THE BLOOD-VASCULAR SYSTEM 118 
 
 HEART 118 
 
 ARTERIES 122 
 
 PULMONARY ARTERY AND AORTA 122 
 
 ARTERIES OF THE HEAD AND NECK 124 
 
 CIRCLE OF WILLIS 128 
 
 TRIANGLES OF THE NECK 128 
 
 ARTERIES OF THE UPPER EXTREMITY 130 
 
 OF THE TRUNK 136 
 
 OF THE LOWER EXTREMITY 141 
 
 ARTERIAL ANASTOMOSES 145 
 
 TABLES AND PLATES OF THE ARTERIAL SYSTEM . 147 
 
 VEINS OF THE HEAD AND NECK 163 
 
 OF THE UPPER EXTREMITY 166 
 
 OF THE THORAX 167 
 
 OF THE LOWER EXTREMITY, PELVIS AND ABDOMEN. . . . 168 
 
 OF THE HEART 171 
 
 THE LYMPHATIC SYSTEM 171 
 
 LYMPHATICS OF THE HEAD AND NECK 172 
 
 OF THE UPPER AND LOWER EXTREMITIES 173 
 
 OF THE PELVIS, ABDOMEN, INTESTINES, THORAX . . . .174 
 
CONTENTS XI 
 
 PAGE 
 
 THE NERVOUS SYSTEM 175 
 
 BRAIN 178 
 
 MENINGES 180 
 
 CEREBRUM 183 
 
 CEREBELLUM 206 
 
 MEDULLA OBLONGATA 208 
 
 NERVE-TRACTS IN THE BRAIN 212 
 
 SPINAL CORD 213 
 
 NERVE-TRACTS IN THE SPINAL CORD 214 
 
 CRANIAL NERVES 216 
 
 GANGLIA OF THE CRANIAL NERVES 223 
 
 SPINAL NERVES .' 226 
 
 CERVICAL NERVES 227 
 
 THORACIC NERVES ' 231 
 
 LUMBAR NERVES 232 
 
 SACRAL AND COCCYGEAL NERVES 233 
 
 SYMPATHETIC SYSTEM 236 
 
 GANGLIATED CORD 237 
 
 GREAT PLEXUSES 239 
 
 TABLES AND PLATES OF THE NERVOUS SYSTEM. . 243 
 
 ORGANS OF SPECIAL SENSE 270 
 
 SKIN 270 
 
 APPENDAGES OF THE SKIN . 272 
 
 TONGUE 273 
 
 NOSE 276 
 
 EYE 280 
 
 SCLEROTIC AND CORNEA 281 
 
 CHOROID, CILIARY BODY AND IRIS 283 
 
 RETINA 285 
 
 MUSCLES AND NERVES OF THE EYEBALL 289 
 
 VESSELS AND NERVES OF THE EYE 289 
 
 APPENDAGES OF THE EYE 293 
 
 EAR 296 
 
 EXTERNAL EAR 297 
 
 MEMBRANA TYMPANI 298 
 
Xll CONTENTS 
 
 PAGE 
 
 TYMPANUM 300 
 
 EUSTACHIAN TUBE 303 
 
 INTERNAL EAR 304 
 
 AUDITORY NERVE 310 
 
 ORGANS OF DIGESTION 312 
 
 MOUTH 312 
 
 PALATE AND TONSILS 313 
 
 SALIVARY GLANDS 315 
 
 TEETH 317 
 
 PHARYNX . . '. 320 
 
 (ESOPHAGUS - 322 
 
 ABDOMEN 323 
 
 PERITONEUM 325 
 
 STOMACH 328 
 
 SMALL INTESTINE 33 o 
 
 LARGE INTESTINE 333 
 
 LIVER 33 6 
 
 STRUCTURE . . .' 339 
 
 VESSELS 341 
 
 EXCRETORY APPARATUS. 342 
 
 PANCREAS 343 
 
 LESSER PANCREAS 344 
 
 DUCTLESS GLANDS 344 
 
 THYROID AND THYMUS GLANDS 345 
 
 SPLEEN 348 
 
 ORGANS OF VOICE AND RESPIRATION 350 
 
 LARYNX 350 
 
 TRACHEA AND BRONCHI 355 
 
 PLEURAE 356 
 
 MEDIASTINUM 356 
 
 LUNGS 357 
 
 THE URINARY ORGANS . . 360 
 
CONTENTS Xlll 
 
 PACE 
 
 KIDNEYS 360 
 
 URETERS 363 
 
 SUPRA-RENAL CAPSULES 364 
 
 BLADDER 365 
 
 MALE URETHRA 3 68 
 
 FEMALE URETHRA 37 
 
 THE MALE ORGANS OF GENERATION 370 
 
 URETHRAL GLANDS IN THE MALE 370 
 
 PENIS 37i 
 
 TESTES 372 
 
 APPENDAGES OF THE TESTES 375 
 
 THE FEMALE ORGANS OF GENERATION 377 
 
 VULVA 377 
 
 VAGINA 379 
 
 UTERUS 380 
 
 APPENDAGES OF THE UTERUS 382 
 
 MAMM.E 383 
 
 HSRNIA 384 
 
 INGUINAL HERNIA 385 
 
 FEMORAL HERNIA 388 
 
 THE PERINJEUM 39* 
 
 PELVIC CAVITY AND FASCIA 391 
 
 MALE PERINEUM 393 
 
 ISCHIO-RECTAL REGION 394 
 
 FEMALE PERINEUM 395 
 
 LITHOTOMY 396 
 
 INDEX . 399 
 
XIV 
 
 ABBREVIATIONS EXPLANATION 
 
 ABBREVIATIONS 
 
 Anas. . . 
 Ant. . . 
 Art. or A. 
 Asc. . . 
 Br. . . . 
 Cerv. . . 
 Com. . . 
 Commun. 
 Desc. . . 
 Ext. 
 
 Anastomoses. 
 
 Inf. . . . 
 
 Inferior. 
 
 Anterior. 
 
 Int. . . . 
 
 Internal. 
 
 Artery. 
 
 L 
 
 Left. 
 
 Ascending. 
 
 M 
 
 Middle. 
 
 Branch. 
 
 N 
 
 Nerve. 
 
 Cervical. 
 
 PI 
 
 Plexus. 
 
 Common. 
 
 Post.. . . 
 
 Posterior. 
 
 Communicating. 
 
 R 
 
 Right. 
 
 Descending. 
 
 Sup. . . . 
 
 Superior. 
 
 External. 
 
 Superf . . . 
 
 Superficial. 
 
 Trans . 
 
 . Transverse. 
 
 
 EXPLANATION 
 
 Figures or letters in parentheses, .thus (14), (a), refer to the same 
 figures or letters on the adjoining illustration; except in the Tables of 
 Arteries, in which figures in parentheses serve as cross-references to other 
 divisions of the tables. 
 
A COMPEND OF 
 
 HUMAN ANATOMY 
 
 The term Anatomy is derived from the Greek a.va, through, and 
 T\nvi,v, to cut, it strictly means dissection, but is technically applied to 
 that science which treats of the structure of organized bodies. 
 
 The divisions of Descriptive Human Anatomy are, Osteology, the 
 anatomy of the bones; Syndesmology, of the joints; Myology, of the muscles; 
 Angiology, of the vessels; Neurology, of the nerves; Splanchnology, of the 
 internal viscera; Adenology, of the glands; Dermatology, of the skin; 
 Genesiology, of the generative organs. 
 
 OSTEOLOGY 
 
 The number of Bones in the Adult Human Skeleton is variously 
 stated by different anatomists. Excluding the teeth (which belong to 
 the tegumentary system), the Wormian and the sesamoid bones, the 
 number is 206. Excluding also the 6 ossicles of the middle ear the whole 
 number would be 200. Leaving out also the 2 patellae and the hyoid 
 bone, the number in the skeleton proper would be 197 bones. Of these, 
 the vertebral column contains 26, the cranium 8, the face 14, the walls of 
 the thorax (sternum and ribs) 25, the upper extremities 64, and the lower 
 extremities 60. They are divisible into four classes, the long and short 
 medullated, and the flat and irregular cancellous bones. 
 
 Long Bones number 90, act as supports, or levers, and are known by 
 having a medullary canal. in the centre of each, a shaft (diaphysis), and 
 two extremities. They are developed by osseous deposit in cartilage, and 
 include the clavicle, humerus, radius, ulna, femur, tibia, fibula, meta- 
 carpal and metatarsal bones, and the phalanges. 
 
 Short Bones number 30, and are found where strength is required, but 
 limited motion. They are also developed by osseous deposit in cartilage 
 and include the bones of the carpus and tarsus, the former having 16 and 
 the latter 14. 
 
2 HUMAN ANATOMY 
 
 Flat Bones number 38, protect the viscera by forming walls around them, 
 and afford extensive attachment for muscles. They are developed by 
 osseous deposit in membranes, and consist of 2 dense layers, separated by 
 a cellular or cancellous osseous tissue, the diploe. They include the oc- 
 cipital (os occipitale), parietal (os parietale), and frontal (os frontale) 
 '(bones of the cranium); the nasal (os nasale), lacrimal (os lacrimale), 
 and vomer (bones of the face); the scapula, os innominatum (os coxae), 
 sternum and ribs (costae). 
 
 Irregular Bones are 39 in number, and include the vertebrae, sacrum, 
 coccyx (coccygis), the temporal, ethmoid, and sphenoid bones, and 
 the bones of the face, except the nasal (os nasale), lacrimal (os lacrimale), 
 and vomer. 
 
 Bones of the Head number 22, and comprise the 
 Cranial Bones 8, the frontal, 2 parietal (ossa parietalia) , occipital (os 
 
 occipitale), 2 temporal (ossa temporalia), the sphenoid and the ethmoid 
 
 (os ethmoidale) . 
 Facial Bones 14, 2 maxillary (maxillae), 2 malar (ossa zygomatica), 2 
 
 nasal (ossa nasalia), 2 lacrrmal (ossa lacrimalia), 2 palate (ossa 
 
 palatina), 2 inferior turbinal (conchae nasales inferiores), vomer and 
 
 mandible. 
 
 Bones of the Trunk number 53, as follows, viz. 
 Vertebra 24, 7 cervical, 12 thoracic, and 5 lumbar vertebrae. 
 Thorax 25, 7 pairs of true ribs, 3 pairs of false ribs, 2 pairs of floating 
 
 ribs (articulating with the bodies of the thoracic vertebrae), and the 
 
 sternum. 
 Pelvis 4, the sacrum, the coccyx (os coccygis), and 2 ossainnominata (ossa 
 
 coxae) each os innominatum consisting of 3, the ilium (coxae), 
 
 ischium, and pubis. 
 
 Bones of each Upper Extremity number 32, as follows: 
 Shoulder 2, the clavicle (clavicula) and scapula. 
 Arm i, the humerus. 
 Forearm 2, the radius and ulna. 
 Hand 27, 8 carpal bones, the scaphoid (os naviculare), semilunar (os 
 
 triquetrum), cuneiform, pisiform (os pisiforme), trapezium (os mul- 
 
 tangulum majus), trapezoid (os multangulum minus), os magnum 
 
 (os capitatum), and unciform (os hamatum), 5 metacarpal, and 14 
 
 phalanges. 
 
 Bones of each Lower Extremity number 29, viz. 
 Thigh i, the femur. 
 Leg 2, the tibia and fibula. 
 
OSTEOLOGY 3 
 
 Foot 26, 7 tarsal bones, the astragalus (talus), os calcis (calcaneus), 
 
 scaphoid, (naviculare pedis), cuboid (os cuboideum), external, (tertium) 
 
 middle (secundum), and internal cuneiform (primum), 5 meta tarsal, 
 
 14 phalanges. 
 
 Unclassified Bones are the 
 Patella 2, which are sesamoid bones, each developed in the tendon of the 
 
 quadriceps extensor femoris muscle. 
 Hyoid Bone (os hyoideum) i, the tongue-bone not articulated to the 
 
 skeleton. 
 Malleus, Incus Stapes (3 pairs), the bones of the middle ear (ossicula 
 
 auditis). 
 Sesamoid Bones, of variable number, situated in the tendons of the 
 
 gastrocnemius and peroneus longus muscles, and in the flexor tendons 
 
 of the great toe and the thumb. 
 Wormian Bones (ossa Suturarum), sometimes found in the cranial 
 
 sutures, are not constant in number or size. 
 
 Principal Eminences on Bones. Heads are convex and smooth, for 
 articulation in movable joints. Condyles are irregularly shaped heads. 
 Trochamers, when for turning the bone. Tuberosities are broad, uneven 
 prominences. Tubercles are small tuberosities. Spines, or Spinous proc- 
 esses, when sharp and slender. Apophysis (an excrescence), is a process 
 or marked bony prominence which has never been separate from the 
 bone. Epiphysis (an accretion), is a process which was developed sepa- 
 rately and afterward became united to the bone by ossification of the 
 intermediate tissue. 
 
 Other Names given to Bony Prominences. There are several adject 
 tives applied to them from their fancied resemblances, such as Azygod, 
 without a fellow; Clinoid, like a bed; Coracoid, like a crow's beak; Coronoi,- 
 hooked like a cow's horn; Hamular, hook-like; Malleolar, like a mallet; 
 Mastoid, like a nipple; Odontoid, tooth-like; Pterygoid, wing-like; Rostrum, 
 a beak; Spinous, thorn-like; Styloid, pen-like; Squamous, scaly; Vaginal, 
 ensheathing, etc. 
 
 Cavities of Bones. Articular cavities are called Cotyloid, cup-like; 
 Ctenoid, shallow; Trochlear, pulley-like; Facet, if smooth; Alveolar or 
 Alveoli, when socket-like. Non-articular cavities are named fossae, sinu- 
 ses, aqueducts, foramina, canals, fissures, notches, cells, grooves, depres- 
 sions, etc. 
 
 Composition of Bone. Organic or animal matter, about ^, consisting 
 of gelatin, vessels and fat. Inorganic, or mineral, about %, consisting of 
 
4 HUMAN ANATOMY 
 
 phosphate and carbonate of calcium (62^ per cent.), with fluoride of 
 calcium, phosphates of magnesium, sodium, and chloride of sodium (4^ 
 per cent.). Heat will remove the organic matter and leave the inorganic; 
 dilute Nitric or Hydrochloric acid will remove the inorganic, and leave the 
 organic. In old age the inorganic constituents predominate, and the bones 
 are brittle; in youth the organic predominate, and epiphyseal dislocation 
 is more common than fracture, especially in the long bones of the 
 extremities. 
 
 Structure of Bone. Bone is composed of an outer compact layer, and 
 an inner cellular or spongy structure. It is surrounded, except at the articu- 
 lar cartilages, by a vascular fibrous membrane, the Periosteum, which 
 receives the insertions of all tendons, ligaments, etc.; and the central cavity 
 of long bones is lined by a similar structure, the Endosteum. The trans- 
 verse section of the bone, examined microscopically, shows 
 
 Haversian Canals, diameter /^oo inch, for the passage of vessels. 
 
 Canaliculi, diameter Keooo inch, radiating from the canals, and con- 
 necting them with the lacunae. 
 
 Lacuna, arranged circularly around the canals, and contain the 
 bone-cells, appearing as irregular dark spaces. 
 
 Haversian Spaces, connect the canals with the medullary spaces, and 
 divide one Haversian system from another. An Haversian System 
 comprises an Haversian canal with its lamellae, lacunae, and canaliculi. 
 
 Concentric Lamella, of bone tissue, around the canals. 
 
 Circumferential Lamella, are bone layers binding the canals together. 
 ~j Interstitial Lamella, woven in between the concentric lamellae. 
 
 The Marrow of Bone. In young bones it is a tenacious, transparent 
 fluid, free from fat. In adult bones it is of a yellow color, and consists 
 of fat in varying proportion and extractive matters. It is found in the 
 medullary canal, the cancellous texture, and the large Haversian spaces. 
 
 Vessels found in Bones. Arteries, veins, and some say lymphatics. 
 The Arteries are, the nutrient, entering at the nutrient foramen; the 
 articular, nourishing the cancellous structure; and the periosteal, which 
 supply the periosteum and the compact structure. The Veins emerge 
 from the ends, the shaft, and from the nutrient foramen. 
 
 The process of Ossification. The site of bone is first occupied by a 
 mucoid substance, which becomes temporary cartilage (blastema) in the 
 second month of foetal life. The young bone-cells (osteo-blasts) are 
 then deposited in the cartilage at certain points, and their deposition 
 and subsequent pressure cause the absorption of the cartilage. In most of 
 the bones of the head and face, ossification is intra-membranous instead 
 
THE VERTEBRAL COLUMN 5 
 
 of intra-cartilaginous. The first bones in which ossification appears are 
 the clavicle and inferior maxillary (5th to 7th foetal week); the last is the 
 pisiform bone (i2th year). Epiphyses ossify after birth and begin uniting 
 to the bone from the age of puberty, and in the inverse order to that in 
 which their ossification began, except the lower end of the fibula, which 
 ossifies and is joined to the shaft earlier than its upper end. 
 
 , THE BONES OF THE TRUNK 
 
 A*- 3V 
 
 THE VERTEBRAL COLUMN 
 
 Characteristics common to the Vertebrae. Each of the 24 spinal 
 vertebrae consists of a body and an arch, the latter being formed by 2 
 radix arcus vertebrae (pedicles) and 2 laminae, which support 7 processes. 
 The 
 
 Body (corpus vertebrae) is thick and spongy, convex in front (i) from side 
 
 to side, concave vertically, and on the upper and lower surfaces, which 
 
 are surrounded by a bony rim. PIG. i. 
 
 Anteriorly are small foramina 
 
 for nutrient vessels, posteriorly 
 
 a large foramen for the exit of 5! 
 
 the venae basis vertebrarum. 
 Pedicles (radix arcus vertebrae) (7), 
 
 project backward from the 
 
 body, inclining outwardly. 
 
 They are notched above and 
 
 below (incisura vertebralis su- 
 perior et inferior), thus form- 
 ing, with the adjacent notches, 
 
 the Inter vertebral Foramina 
 
 (Foramina Intervertebralia) for the entrance of vessels and the exit 
 
 of the spinal nerves. 
 Lamina, are 2 broad plates, meeting in the spinous process behind, 
 
 and rough on their upper and lower borders for the attachment of 
 
 the ligamentum subflava. 
 Transverse Processes (4), one on each side projecting outward; those 
 
 of the first ten thoracic vertebrae have articular facets (5) for the 
 
 tubercles of the ribs. 
 Articular Processes (Zygapophyses) (6), two on each side, superior 
 
 (6) and inferior, project from the junction of the laminae and pedicles, 
 
 and articulate above and below with the articular processes of the 
 
HUMAN ANATOMY 
 
 adjacent vertebrae. Their upper facets look backwards and upwards 
 in the cervical region, backwards and outwards in the thoracic, and 
 backwards and inwards in the lumbar. 
 
 Spinous Process (3), projects backward from the junction of the laminae 
 with each other, sometimes very obliquely. 
 
 Spinal Foramen (foramen vertebrale) (2), is the space enclosed by the 
 body, pedicles and laminae, and which, when the vertebrae are articu- 
 lated, forms part of the spinal or neural canal. 
 
 The Spinal Vertebrae are distinguished as cervical 7, thoracic 12, 
 and lumbar 5. Each of these divisions has several peculiar features, but 
 their especial characteristics are as follows: 
 
 Cervical Vertebra, are pierced at the bases of their transverse processes 
 by the costo-transverse foramina, which transmit the vertebral artery, 
 vein, and plexus. The anterior boundary of a costo-transverse 
 foramen is called the Costal process, it is a true cervical rib. Its 
 termination is called anterior tubercle of the transverse process. The 
 posterior tubercle is the tip of the true transverse process. The 
 superior articular facets look backwards and upwards. 
 
 Thoracic Vertebrae, have facets and demifacets on their bodies, for 
 articulation with the heads of the ribs, these facets are called the 
 foveae costales. The superior articular facets look backwards and 
 outwards. 
 
 Lumbar Vertebra, are marked by the absence of the foramina and facets 
 which distinguish the other two classes. The superior articular facets 
 look backwards and inwards. 
 
 Peculiar Vertebrae are 9 in number, the Atlas or ist cervical, the Axis 
 or 2d cervical (epistropheus), the Vertebra Prominens, or 7th cervical 
 
 (the ist thoracic is nearly always 
 more prominent), the ist, Qth, 
 icth, nth, and i2th thoracic, 
 and the 5th lumbar. The 
 ^Jlas (3), is a bony ring sup- 
 porting the head. A bony 
 arch takes the place of a 
 body, and its spinous process 
 is a mere tubercle. Its Lat- 
 eral Masses (i) form its 
 
 chief bulk, supporting large Articular Processes (foveae articulares), 
 which look inwards, the superior (2) articulating with the condyles 
 of the occipital bone. 
 
 FIG. 2. 
 
THE THORAX 7 
 
 Axis (9), is marked by its Odontoid Process (dens) (10) projecting up- 
 ward from the body into the anterior part of the spinal foramen of 
 the atlas, where it articulates with the anterior arch (3), and receives 
 the occipito-axoid (ligamentum apicis dentis) and the check liga- 
 ments (ligamenta alaria). Its transverse processes (8) are very small 
 and are not bifid. Its inferior articular surfaces (7) have the same 
 direction as those of the other cervical vertebrae. 
 
 Vertebra Prominens, has a long and prominent spinous process which 
 ends in a tubercle for the ligamentum nuchae. 
 
 Thoracic Vertebra. The ist has one facet and a demifacet for the ist 
 and 2d ribs. The gth has a demifacet only. The loth has but one 
 facet on the body and one on the transverse process. The nth and 
 1 2th have each but one facet on the body, and none on the transverse 
 processes. The i2th resembles a lumbar vertebra in size and shape. 
 
 5th Lumbar Vertebra, is much deeper in front than behind; its spinous 
 process is small, but its transverse processes are large and thick, and 
 point slightly upward. 
 
 Important Relations of Certain Vertebrae. 
 
 3<f Cervical corresponds in situation to the bifurcation of the common 
 carotid artery, and the superior cervical ganglion. 
 
 5fh Cervical, to the junctions of the larynx with the trachea and the 
 pharynx with the oesophagus, and the middle cervical ganglion of the 
 sympathetic. 
 
 id Lumbar, to the junction of the duodenum with the jejunum, the com- 
 mencement of the thoracic duct and the portal vein, the origin of the 
 superior mesenteric artery, the lower margin of the pancreas, the opening 
 of the ductus communis choledochus, the lower end of the spinal cord, 
 and the crura of the diaphragm. 
 
 [The sacral and coccygeal vertebrae are described as bones of the pelvis.] 
 
 THE THORAX 
 
 The Thorax is an osseo-cartilaginous cage formed by the bodies of the 
 dorsal vertebrae posteriorly, the ribs and costal cartilages laterally, and 
 the sternum in front. Its shape is conical, the axis inclined forward, the 
 base below and closed by the diaphragm. 
 
 Structures passing through its Apex, are the trachea, oesophagus, 
 large vessels of the neck, pneumogastric (vagus), phrenic, and sympathetic 
 nerves, thoracic duct, and in inspiration the apex of the lung. 
 
8 
 
 HUMAN ANATOMY 
 
 FIG. 3. 
 
 Structures contained in its Cavity, are the trachea, bronchi and 
 lungs, the heart and great vessels, internal mammary arteries, azygos and 
 bronchial veins, pneumogastric, phrenic, and splanchnic nerves, oesopha- 
 gus, thoracic duct, lymphatic vessels and glands. 
 
 The Sternum, or breast-bone, consists of 3 parts the manubrium (i), 
 or handle; the gladiolus (2), or sword; and the ensiform or xiphoid appen- 
 dix (3). It presents the 
 
 Inter clavicular Notch, on its superior border. 
 
 Manubrium (i), articulates 
 with the clavicle, ist costal 
 cartilage, and a part of 
 the 2d. 
 
 Gladiolus (2), articulates 
 with the costal cartilages 
 from the 3d to the 6th in- 
 clusive, and partly with 
 the 2d and 7th. 
 Ensiform Appendix (3), ar- 
 ticulates with the cartilage 
 of the false ribs, and in 
 part with the 7th costal 
 cartilage. It is cartilag- 
 inous in youth. 
 Development and Muscles. 
 The sternum is developed- by 6 
 centres, i each for the manu- 
 brium and ensiform appendix 
 and 4 for the gladiolus. The 
 muscles attached to it are 9 pairs and one single muscle, the sterno- 
 cleido-mastoid, sterno-hyoid and sterno-thyroid, 3, to its upper part; 
 the rectus abdominis, external and internal oblique, transversalis and the 
 diaphragm, 5, to its lower part; the pectoralis major, i, anteriorly; 
 and the triangularis sterni, i, posteriorly. 
 
 The Ribs are 12 in number on each side, 7 of which are true ribs, being 
 each connected to the sternum by a separate cartilage; and 5 are false 
 ribs. Three of the latter are connected by their cartilages to the cartilage 
 of the 7th rib (n), while two are called floating ribs (10), having each one 
 extremity free. 
 
 Characteristics Common to most of the Ribs. Each rib consists of 
 a head, neck and shaft, and presents the following points, viz. 
 
THE PELVIS 9 
 
 Head, is divided by a ridge into 2 facets, which articulate with the 
 facets on the bodies of the dorsal vertebrae, the lowermost facet is 
 always slightly the larger; the ridge giving attachment to the inter- 
 articular ligament. 
 
 Neck about an inch long, presents on its upper border a crest which 
 affords attachment to the ligamentum costo-transversarium anterius 
 (superior costo-transverse), to its posterior surface the middle costo- 
 transverse ligament (1. colli costae), its anterior surface is smooth. 
 
 Tuber osity, at the junction of the neck with the shaft, has a facet for 
 articulation with the transverse process of the next lower vertebra, 
 and a rough surface for the posterior costo-transverse ligament 
 (1. tuberculi costae). 
 
 Shaft, twisted on itself, is concave internally, convex externally, its 
 upper border round and smooth, its lower border grooved for the 
 intercostal vessels and nerves. At its external extremity is an oval 
 depression for the insertion of the costal cartilage. 
 
 Angle, just in front of the tuberosity, is marked by a rough line, to 
 which are attached the muscles of the deep layer of the back. 
 
 Development. Each rib has 3 centres, one each for the head, shaft, 
 ind tuberosity. The last 2 ribs, having no tuberosity, are developed 
 each by 2 centres. 
 
 Peculiar Ribs, are the ist, 2d, loth, nth, and i2th. They respectively 
 present the following peculiarities 
 
 ist Rib, is broad, short, not twisted, has no angle, only one facet on 
 the head; but on its upper surface are seen two grooves for the subclavian 
 artery and vein, and between them a tubercle for the scalenus anticus 
 muscle. 
 
 2d Rib, is not twisted, its tuberosity and angle are very close together, 
 and its upper surface presents rough surfaces for the serratus magnus 
 and scalenus posticus muscles. 
 
 loth Rib, has but one facet on its head. 
 
 nth Rib, has no neck, no tuberosity, and but one facet on its head. 
 
 i2th Rib, has neither neck, angle, tuberosity nor groove, and but one 
 facet on its head. 
 
 THE PELVIS 
 
 The Pelvis is formed by the sacrum, os coccygis (coccyx), and two ossa 
 innominata (coxae) and is divided into, the pelvis major (false pelvis), 
 comprising the upper and expanded portion, and the pelvis minor 
 (true pelvis), below the ilio-pectineal line (linea arcuata). The false 
 
10 
 
 HUMAN ANATOMY 
 
 FIG. 4. 
 
 pelvis corresponds to the iliac fossae (i), and is marked by its walls being 
 deficient anteriorly between the iliac borders, and posteriorly between the 
 sacrum and the posterior iliac spines. The true pelvis has a 
 
 Brim, or inlet (apertura pel vis minor superior), bounded in front by 
 the crest and spine of the pubes (7), behind by the promontory of 
 the sacrum (15), laterally by the ilio-pectineal line (linea arcuata). 
 Its axis corresponds to a line intersecting the umbilicus and the middle 
 of the coccyx (os coccygis). Its average diameters in the female 
 are, 4 inches antero-posteriorly, over 5 inches transversely, under 5 
 
 inches obliquely. In the 
 male each of these meas- 
 urements is about % an 
 inch less. 
 
 Cavity, is a short curved 
 canal, connecting the 
 brim with the outlet. 
 In front its depth is about 
 i% inches, posteriorly 4 
 to 4^ inches in the 
 female, 4^ to 5^ inches 
 in the male. Its diameter 
 is about 4% inches in the 
 female, 4> inches in the 
 male, all around. 
 
 Outlet (apertura pelvis minor inferior), is bounded by the pubic arch 
 
 above (n), the tip of the coccyx (os coccygis) behind, and the 
 
 tuberosities of the ischia (9) laterally. Its axis, if prolonged, would 
 
 touch the promontory of the sacrum. Its diameters in the female are 
 
 each about 4^ inches, in the male about 3^ inches. 
 
 Chief Differences between the male and female pelves. The male 
 
 pelvis is marked by strength of the bones, prominence of the muscular 
 
 impressions, a deep and narrow cavity, and large obturator foramina. 
 
 The female pelvis has lighter bones, broader iliac fossae, the spines being 
 
 further apart, greater diameters at every point, the sacrum less curved, 
 
 and the pubic arch wider. 
 
 The Sacrum, or sacred bone, is triangular, curved, with its convexity 
 backward, and is situated, base upwards, between the ossa innominata 
 (coxae) forming with the coccyx the posterior wall of the pelvis. The bone 
 consists of a central portion (4) which consists of the coalesced bodies 
 of five vertebrae, and on each side a pars lateralis (lateral mass) or ala (wing) 
 
THE PELVIS 
 
 II 
 
 FIG. 5. 
 
 which is made by the fusion of the transverse processes and what might 
 be called "pelvic ribs." Therefore the pars lateralis presents a trans- 
 verse portion and a costal or alar portion. The sacrum presents the 
 following points, viz. 
 
 Ridges (cristae sacral es articulares) (4), four transversely across both 
 surfaces, mark the union of its original seg- 
 ments. 
 
 Anterior Sacral Foramina, eight for the an- 
 terior sacral nerves. 
 
 Grooves (5), eight shallow and broad, for the 
 aforesaid nerves. 
 
 Promontory, at its junction with the last lum- 
 bar vertebrae. 
 
 Posterior Sacral Foramina, eight for the pos- 
 terior sacral nerves. 
 
 Tubercles, representing the spinous processes 
 of the segments. 
 
 Groove, posteriorly, on each side of the spinous tubercles. 
 
 Cornua, two at the posterior inferior portion of the bone. 
 
 Articular Surface (3), on each side, articulates with the ilium. 
 
 Notch, laterally and inferiorly, for the 5th sacral nerve. 
 
 Base (2), has all the characteristics of the lumbar vertebrae, with the 
 last of which it articulates. 
 
 Apex (16), has an oval surface for articulation with the coccyx. 
 
 Sacral Canal, the continuation of the spinal canal, is incomplete pos- 
 teriorly at its lower end. It transmits the Cauda Equina; into it 
 open the sacral foramina laterally. 
 
 The Coccyx consists of 4 (or 5) rudimentary caudal vertebrae coalesced 
 FlG 6 into a triangular bone, the base (i) of which articu- 
 
 lates with the apex of the sacrum. Its posterior sur- 
 face is rough for muscles and ligaments, its anterior 
 surface is smooth and marked by ridges at the junction 
 of its constituent vertebrae. It presents the following 
 points: 
 
 Cornua (2), two superiorly,, articulating with the 
 sacral cornua to form foramina for the 5th sacral nerves. 
 Apex, is sometimes bifid and turned to one side. 
 
 The Ossa Innominate (coxae), are placed one on each side of the 
 osseous pelvis, and are each formed by the union, about puberty, 
 
12 HUMAN ANATOMY 
 
 of 3 bones, the ilium, ischium, and pubes. The innominate (os coxae) 
 as a whole presents the following points, viz. 
 
 It is a large flat bone, constricted in the middle, and twisted upon its 
 long axis, so that the expanded portion (iliac) above the constriction is in 
 a plane almost at right angles to that of the expanded portion (ischio- 
 pubic) below. It presents an outer surface, an inner surface, and a con- 
 tinuous border which is circumferential. Beginning at its upper part the 
 border of the os coxae (innominate or hip bone), it presents a crest (i), 
 and, continuing forwards and around, the anterior superior spine (2), 
 a shallow notch, the anterior inferior spine (4), a smaller notch, the ilio- 
 pectineal eminence (5), superior (ascending) ramus or body of the ossis 
 pubis, pubic tubercle (spine) and crest of pubis (9), the symphysis ossis 
 pubis, the ischio-pubic ramus (9), constituted in front by the inferior (hori- 
 zontal or descending) ramus of the pubis and behind by the ramus of the 
 ischium, the tuber ischiadicum (tuberosity of the ischium) 12, the lesser 
 sciatic (sacro-sciatic) notch (13), the ischial spine 14, the greater sciatic 
 (sacro-iliac) notch (16), the posterior inferior spine of the ilium (17), and 
 lastly the posterior superior spine of the ilium. The inner surface is divided 
 by the ilio-pectineal line into an upper portion and a lower portion. The 
 upper portion (false pelvis) presents in front the iliac fossa, and behind, the 
 articular (auricular) surface and a rough surface for the posterior sacro- 
 iliac ligament. The lower part of the inner surface (true pelvis) presents 
 the obturator groove and the obturator foramen (8). In addition to 
 what is described with the ilium, ischium and pubes, the outer surface 
 presents : 
 
 Acetabulum, or cotyloid cavity, receives the head of the femur. It is 
 situated at the junction of the 3 bones externally, the ilium and 
 ischium each forming about two-fifths, and the pubic bone one-fifth 
 of it. A depression in its centre lodges a mass of fat containing 
 vessels for the nourishment of the synovial membrane. The Cotyloid 
 Notch (Incisura Acetabuli) is a deficiency in its lower margin, trans- 
 mitting nutrient vessels to the joint; to the edges of the notch is 
 attached the ligamentum teres, and it is bridged over by the trans- 
 verse ligament, a continuation of the cotyloid ligament (labrum 
 glenoidale) which surmounts the brim of the acetabulum. Crossing 
 the ischium horizontally, immediately below the acetabulum, is a 
 deep groove for the obturator externus tendon. 
 
 Obturator or Thyroid Foramen (8), on the anterior surface between the 
 pubes and ischium, large and oval in the male, small and triangular 
 in the female; is closed by the obturator membrane, except above 
 
THE PELVIS 13 
 
 at the obturator canal or groove where the obturator nerves and 
 
 vessels pass through. 
 
 The Ilium is the superior part of the innominate bone, its outer surface 
 presents the following points, viz. 
 
 Crest (i), along its upper border, having an outer and inner lip for 
 
 muscular attachment, and ending in the superior spines. 
 Anterior Superior Spine (2), to which are attached the sartorius and 
 
 tensor fasciae (vaginae) femoris muscles and the inguinal (Poupart's) 
 
 ligament. 
 
 Anterior Inferior Spine (4), for the straight tendon of the rectus femoris. 
 Notch, between the above-named spines, 
 
 transmitting the external (lateral) cu- 
 taneous nerve, and lodging some fibres 
 
 of the sartorius. 
 
 Posterior Superior Spine (19), for the at- 
 tachment of the erector spinae muscle, 
 
 and the oblique part of the sacro-iliac 
 
 ligament. 
 Posterior Inferior Spine (17), for the sacro- 
 
 tuberous (great sacro-scia tic) ligament. 
 Great Sciatic (Sacro-iliac) Notch (16), 
 
 below the last-named spine, transmits 
 
 the great sciatic, superior gluteal, and 
 
 pudic (pudendal) nerves, the pyriformis 
 
 muscle, and the sciatic, pudic (pudendal) and gluteal vessels, also a 
 
 nerve supplying the obturator externus muscle. 
 Gluteal ridges (Curved Lines) (21) posterior, anterior, and inferior, on 
 
 the outer surface of the bone, from the spaces between which arise 
 
 the glutei muscles. 
 Groove, above the acetabulum, for the reflected tendon of the rectus 
 
 femoris muscle. 
 
 The Ischium is the lowermost portion of the os coxae (innominate bone), 
 and presents the following points, viz. 
 
 B ody (superior ramus), forms two-fifths of the acetabulum, and the 
 
 external margin of the obturator foramen; on it is a broad groove for 
 
 the tendon of the obturator externus muscle. Its posterior margin 
 
 assists in forming the great sciatic (sacro-sciatic) notch. 
 Spine (14), for the gemellus superior, coccygeus, and levator ani 
 
 muscles, and the lesser sacro-sciatic ligament. 
 Lesser Sciatic (Sacro-sciatic} Notch (13) below the spine, transmits the 
 
14 HUMAN ANATOMY 
 
 obturator muscle, its nerve, and the pudic vessels and nerve as 
 they re-enter the pelvis, having crossed the spine of the ischium. 
 The sacro-sciatic notches are converted into foramina by the sacro- 
 sciatic ligaments; the greater notch by the lesser ligament (sacro- 
 spinous), the lesser notch by the greater ligament (sacro-tuberous). 
 
 Tuberosity (12), the lowest and most prominent part, gives attach- 
 ment to the greater sacro-sciatic (sacro-tuberous) ligament, and to 
 several muscles. On it one rests when sitting. 
 
 Horizontal Ramus (inferior ramus), bounds the obturator foramen 
 inferiorly, articulates with the (descending) (inferior) ramus of the 
 pubes, and gives attachment to the obturator membrane and several 
 muscles. 
 
 The Pubes. The pubic or pectineal bone forms the anterior portion 
 of the innominate. It presents the following points, viz. 
 
 Body, with its fellow forms the Symphysis, giving origin to several 
 muscles and ligaments. 
 
 Crest (9), on the upper part of the body, terminates externally in the 
 spine. 
 
 Spine, affords attachment to one end of inguinal (Poupart's) ligament. 
 
 (Linea Ilio-pectinea), (pecten ossis pubis) in part, gives attachment to 
 the conjoined tendon, Gimbernat's (lacunar) ligament, and the tri- 
 angular ligament. 
 
 Horizontal Ramus, forms part of the margin of the obturator fora- 
 men, and of the acetabulum. 
 
 Pectineal Eminence (5), gives attachment to the psoas parvus muscle. 
 
 Muscles attached to the hip bone number 36, comprising those of 
 the abdomen, thigh, perineum, floor of the pelvis, and rotators of the 
 hip-joint. 
 
 THE BONES OF THE HEAD 
 
 THE FRONTAL BONES (OS FRONTALE), (i, Fig. 8) 
 
 Points on its Frontal (Vertical) Portion, are as follows: 
 Externally, An upper angle (6), Lateral angles (12), 
 Frontal Eminences (tuberosities) , one on each side of the median line. 
 Depression, marking the site of the frontal (metopic) suture before 
 
 obliteration. 
 
 Superciliary Arches (Ridges), behind which are the frontal sinuses. 
 Supraorbital Notches or Foramina, in the supraorbital arches, at about 
 
 their inner third, for the supraorbital vessels and nerves. 
 Nasal Eminence (24), at lower end of the frontal depression. 
 
THE FRONTAL BONE 15 
 
 External Angular, (Lateral or Zygomatic) Processes (13), articulate 
 
 with the malar (zygomatic) bones and form the anterior part 
 
 of the temporal ridges. 
 Internal (Medial) Angular Processes, articulate with the lacrimal 
 
 bones. 
 Nasal (Frontal) Spine and Notch, between the internal angular 
 
 processes. 
 Internally, 
 
 Sagittal Sulcus or Groove, for superior longitudinal sinus and the 
 
 falx cerebri. 
 
 Frontal Crest, for attachment of the falx cerebri. 
 Foramen Coecum, for a small vein to the longitudinal sinus. 
 
 FIG. 8. 
 
 Depressions and Elevations, for convolutions of the brain. 
 Between the two tables of the vertical portion in the adult are the 
 Frontal Sinuses, two spaces at the anterior inferior part of the bone, 
 which are lined with mucous membrane, and open into the middle 
 meatus of the nose. 
 
 The Orbital Plates (Pars Orbitalis). Each plate presents the following 
 points, 
 
 Fossa, for the lacrimal gland, near the external angular process. 
 Fovea Trochlearis, a depression at the nasal margin for the pulley of 
 the superior oblique muscle. 
 
1 6 HUMAN ANATOMY 
 
 Ethmoidal Notch, having the following foramina on its margin. 
 Anterior Ethmoidal Foramen, for the anterior ethmoidal vessels and 
 
 the naso-ciliary branch of the ophthalmic nerve. 
 Posterior Ethmoidal Foramen, for posterior ethmoidal vessels. 
 Grooves, on the cranial surface, for branches of the anterior and middle 
 
 meningeal arteries. 
 
 Articulations, Development, and Muscles. Each half of the frontal 
 bone articulates from its upper angle to its lateral angle, with the parietal, 
 from lateral angle to zygomatic process, with the front part of the apex of 
 the Great Wing of the sphenoid, zygomatic process, with the malar, 
 posterior border of orbital plate, with Lesser Wing of the sphenoid, mar- 
 gins of ethmoidal notch with the ethmoid, medial border of the orbital 
 plate from behind forwards, with orbital plate of ethmoid, lacrimal, 
 nasal process of maxilla, frontal spine, with the nasal. It is developed by 2 
 centres in membrane, i for each lateral half. The muscles attached to 
 it are 3 pairs, the temporal, corrugator supercilii, and orbicularis palpe- 
 brarum. 
 
 THE PARIETAL BONES, (2, Fig. 8) 
 
 General Characteristics. They are 2 quadrilateral bones situated 
 at the superior and lateral regions of the cranium. Each has a frontal 
 (anterior superior) angle (6), anterior border, sphenoidal (anterior 
 inferior) angle (10), a lower border, a truncated mastoid (posterior 
 inferior) angle (9), a posterior border, an occipital (posterior superior) 
 angle (7), and an upper border. The articulations are, the superior 
 border of each joins the other by the Sagittal Suture; the anterior border 
 joins the frontal bone forming the Coronal Suture (6) ; the posterior border 
 articulates with the occipital, forming the Lambdoid Suture (7); the inferior 
 border from before backwards with the great wing of the sphenoid (5), 
 squamous and mastoid portions of the temporal (4). Forming the lateral 
 walls of the skull they are named parietal, from paries, a wall. 
 
 Points on each Parietal Bone. Externally the bone is convex and pre- 
 sents for examination, 
 
 Temporal Ridge (13), continuous with the same on the frontal bone, 
 bounded above by the superior temporal line, and below by the in- 
 ferior temporal line. 
 
 Parietal Eminence (tuberosity) , the point where ossification com- 
 menced. 
 
 Parietal Foramen, close to the upper border, transmits an emissary 
 
THE OCCIPITAL BONE IJ 
 
 vein to the superior longitudinal (sagittal) sinus. Is not constant. 
 
 Internally, the bone is concave, and marked by 
 Depressions, for the Arachnoideal Granulations (Pacchionian bodies), 
 
 and for the cerebral convolutions. 
 
 Furrows, for branches of the middle meningeal artery. 
 Groove, for the lateral (transverse) sinus, at the posterior inferior 
 
 angle. 
 Half-groove, along the upper border, for the superior longitudinal 
 
 (sagittal) sinus of the dura mater. 
 
 Development. Each parietal bone is developed from i centre in mem- 
 brane. The only muscle attached to it is the temporal. 
 
 FIG. 9. 
 
 THE OS OCCIPITALE, (3, Fig. 8) 
 
 is a symmetrical bone. Its border presents an upper angle, and on each 
 side, lateral angle, jugular process, jugular notch, petrosal process 
 along the edge of the basilar proc- 
 ess, and the apex of the basilar 
 process. 
 
 General Features and Surfaces. 
 It is trapezoidal in form, curved 
 upon itself, and placed at the pos- 
 terior and inferior region of the 
 cranium. Externally its surface 
 is convex and presents for exami- 
 nation the following, viz. 
 External Occipital Protuberance 
 (5), and Crest (4), for the at- 
 tachment of the ligamentum 
 nuchae. 
 
 Superior and Inferior Nuchal 
 (Curved} Lines, extending 
 outward on each side of the 
 external occipital crest; in one skull in every six there is to be seen 
 a supreme nuchal line above the others. 
 
 Foramen Magnum (2), transmitting the medulla oblongata and its 
 membranes, the vertebral arteries, and the recurrent portions of the 
 spinal accessory nerves. 
 
 Condyles (6), two in number, for articulation with the atlas. 
 Tubercles, i on each condyle, for the check ligaments. 
 
l8 HUMAN ANATOMY 
 
 Anterior Condylar Foramina (canalis hypoglossi), two for the 
 
 hypoglossal nerves. 
 Posterior Condylar Foramina (canalis condyloideus posterior) (3), 
 
 two (often absent) for emissary veins. 
 Jugular Processes (7), two, each partly bounding the foramen lacerum 
 
 posterius basis cranii. 
 Jugular Fossa (8), each forming part of the foramen lacerum posterius 
 
 basis cranii. 
 Internally, the surface is concave, showing 
 
 Fosses, four for the cerebellar and posterior cerebral lobes. 
 
 Internal Occipital Protuberance, where 6 cranial sinuses meet to form 
 
 the torcular (wine-press) Herophili. 
 
 Crucial Ridge, the vertical portion for the falx cerebri and falx cerebelli; 
 the transverse portion for the tentorium cerebelli, having also a groove 
 for the lateral (transverse) sinus. 
 Groove, for the lateral (transverse) sinus, and the inferior petrosal 
 
 sinus, along the postero-lateral border. 
 Internal Openings, of the foramina described above. 
 Basilar Process (i) of the Occipital lies in front of the foramen mag- 
 num (2), articulates with the body of the sphenoid bone, smooth and 
 grooved in the mid-line for the medulla oblongata and pons varolii, which 
 lie upon it, grooved laterally by the inferior petrosal sinuses; rough in- 
 feriorly for the attachment of muscles, and presenting the 
 Pharyngeal Tubercle or Spine, for the attachment of the superior con- 
 strictor muscle of the pharynx and its tendinous raphe. 
 Articulations and Development. The occipital articulates as follows. 
 The condyles articulate with atlas, apex of the basilar process with body 
 of sphenoid, side of basilar process and apex of jugular process with 
 petrous portion of temporal, from jugular to lateral angle with mastoid 
 portion of temporal, from lateral angle to upper angle with parietal. It 
 is developed by 4 centres, i each for the posterior part, the basilar process, 
 and the 2 condyles; its ossification being completed about the 6th year 
 of age. 
 
 Muscles attached to the Occipital Bone. There are 12 muscles at- 
 tached on each side to the following portions, viz. 
 
 Superior Nuchal Line 3, the occipito-frontalis, trapezius, and sterno- 
 
 cleido-mastoid muscles. 
 
 Space between the nuchal lines 2, the complexus and splenius. 
 Space below the inferior nuchal line 3, the obliquus capitis superior, 
 rectus capitis posticus major and rectus capitis posticus minor. 
 
THE TEMPORAL BONE 
 
 Basilar Process 3, the superior constrictor of the pharynx, rectus capitis 
 
 anticus major and rectus capitis anticus minor. 
 Jugular Process i, the rectus capitis lateralis. 
 
 FIG. 10. 
 
 THE TEMPORAL BONES (OSSA TEMPORALIA), (4, Fig. 8) 
 
 Situation and Divisions. They are situated at the inferior lateral 
 portions of the skull, and contain the organs of hearing. Each bone is 
 formed by the union of three parts, namely, the Squamous, Petro-mastoid, 
 and Tympanic. 
 
 The Squamous Portion is a semicircular plate, smooth externally, and 
 grooved internally for the middle 
 meningeal artery, with depres- 
 sions for the cerebral convolu- 
 tions. Externally are seen the 
 Zygomatic Process (d\ or 
 Zygoma, arising by 3 roots, 
 and extending forward to 
 articulate with the malar 
 bone. 
 
 Zygomatic Tubercle (e), at the 
 base of the process, for the 
 external lateral ligament of 
 the lower jaw. 
 
 Anterior Articular Ridge (emi- 
 nentia articularis), formed 
 by the anterior root of the zygoma. 
 
 Mandibular (Glenoid) Fossa (g), between the anterior and posterior 
 articular ridge (middle root of the zygoma) for articulation with 
 the condyle of the lower jaw, and is covered with cartilage. 
 Glaserian Fissure, divides the squamous from the tympanic; it trans- 
 mits the laxator tympani muscle, the tympanic artery, and lodges 
 the processus gracilis of the malleus and the inferior process of the 
 petrous. 
 
 Opening of the Canal of Hugier, lies in the angle between the squamous 
 and petrous portions of the bone; and transmits the chorda tympani 
 nerve. 
 
 Temporal Ridge (/), in part, here known as the suprameatal ridge. 
 THE PETRO-MASTOID, is usually described as consisting of a mastoid 
 portion and a petrous portion. 
 
20 
 
 HUMAN ANATOMY 
 
 FIG. ii. 
 
 The Mastoid Portion. Its cerebellar surface is grooved for the lateral 
 sinus (9); externally it presents the following, 
 
 Mastoid Foramen (h) y the largest of several foramina, for a vein. 
 Mastoid Process, at the tip, for the sterno-cleido-mastoid, splenius, and 
 
 trachelo-mastoid muscles. 
 
 Digastric Fossa (j}, for the posterior belly of the digastric muscle. 
 Occipital Groove (8), for the occipital artery. 
 The Mastoid Cells, in the interior of the mastoid process, open on the 
 
 posterior wall of the middle ear, and are lined with mucous membrane. 
 
 The Petrous Portion is very hard, pyramidal in form, contains the in- 
 ternal ear, projects inward and forward, and presents a base, an apex, a 
 cerebral surface, cerebellar surface, tympanic surface, and basilar surface; 
 
 upper border, anterior border, pos- 
 terior border; the tympanic bone is 
 blended with the inferior border and 
 conceals it. 
 On the Base are seen, the 
 
 Meatus Auditor ius Externus (i), 
 the external opening of the ear. 
 Auditory Process of the Tympanic, 
 a bony ring for the external car- 
 tilage of the ear. 
 
 Apex lies internally, at the base of 
 the skull, forming the outer 
 boundary of the foramen lacerum 
 medium, and contains the internal 
 carotid canal. 
 CEREBRAL (Anterior) Surface, presents from within outward 
 
 Inner Opening of the Carotid Canal (n), for the internal carotid artery 
 
 and plexus. 
 
 Depression, for the Gasserian ganglion of the 5th pair of cranial nerves. 
 Hiatus Canalis Facialis or Hiatus Fallopii, for the great petrosal nerve, 
 
 branch of the middle meningeal artery. 
 Foramen, for the small petrosal nerve. 
 Eminence, over the superior semicircular canal of the ear. 
 Depression, over the tympanum. 
 Cerebellar (Posterior) Surface presents, 
 
 Meatus Auditorius Internus (12), transmits the yth and 8th pairs of 
 cranial nerves and the auditory artery, and lodges a process of dura 
 
THE TEMPORAL BONE 21 
 
 Opening of the Aqu&ductus Vestibuli (13), transmits to the vestibule a 
 
 small artery and vein, and lodges a process of dura mater. 
 Basilar (Inferior) surface, presents from within outward 
 
 Rough Quadrilateral Surface (19), for the origin of the tensor tympani 
 
 and levator palati muscles. 
 Opening of the Carotid Canal, transmitting the internal carotid artery, 
 
 and the carotid plexus of the sympathetic nerve. 
 
 Aqu&ductus Cochlea, transmitting an artery and vein to the cochlea. 
 Jugular Fossa, a depression for the sinus of the internal jugular vein, 
 forming with the occipital bone the foramen lacerum posterius, which 
 transmits that vein and the 8th pair of cranial nerves, etc. 
 Foramen for Jacobson's Nerve (tympanic branch of the glossopharyn- 
 geal), in the ridge between the jugular fossa and the carotid canal. 
 Foramen for Arnold's Nerve (auricular branch of the pneumogastric), 
 
 in the outer wall of the jugular fossa. 
 
 Jugular Surface, for articulation with the jugular process of the occi- 
 pital bone. The Tympanic Surface can be seen by looking in the 
 external auditory canal, forms most of the osseous wall of the middle 
 ear or tympanum. It presents the Promontory of the Cochlea, 
 Fenestra Vestibuli, and Fenestra Cochlea. 
 
 The Tympanic Bone forms most of the external auditory canal. Its 
 under surface is slightly concave, forming a fossa for part of the parotid 
 gland. It presents a sharp ridge which projects downwards, and forms 
 the, 
 
 Vaginal Process (1), ensheathing the root of the styloid process. 
 Styloid Process (14), a long projection for the stylo-pharyngeus, stylo- 
 hyoid, and stylo-glossus muscles; and the stylo-hyoid and stylo- 
 mandibular ligaments, which are attached thereto. 
 Stylo-mastoid Foramen (15), between the styloid and mastoid processes, 
 for the exit of the facial nerve, and the entrance of the stylo-mastoid 
 artery. 
 Auricular Fissure, for the exit of the auricular branch of the vagus 
 
 (Arnold's nerve). 
 
 In the angle between the petrous and squamous portions, are seen the 
 Septum Tuba, a lamina separating the following canals. Its inner end 
 projects into the tympanum, and is called iheProcessus cochleariformis. 
 Opening, of the canal for the tensor tympani muscle. 
 Osseous Opening, of the Eustachian tube (n) inferiorly. 
 The Anterior Border articulates partly with the alar spine of the 
 sphenoid bone. 
 
22 HUMAN ANATOMY 
 
 The Posterior Border assists in forming the jugular foramen, and is grooved 
 
 for the inferior petrosal sinus. 
 The Superior Border separates the anterior fossa of the skull from the 
 
 middle fossa; to it is attached the tentorium cerebelli, and it is grooved 
 
 for the superior petrosal sinus (10), and in infants it presents afloccular 
 
 fossa. 
 
 Articulations and Development. The temporal articulates as follows, 
 Anterior border of the petrous and squamous with the great wing of the 
 sphenoid, upper border of the squamous and mastoid with the parietal, 
 posterior border of the petro-mastoid with the occipital, apex of zygo- 
 matic process with malar, and indirectly the glenoid fossa with the 
 mandible. It is developed by 4 principal centres, one each for the squamous 
 portion, styloid process, and tympanic, and one for the petro-mastoid 
 portions. Its ossification is completed about the 2d or 3d year. 
 
 Muscles attached to it. There are 14 muscles attached to the following- 
 named portions. To the 
 
 Squamous Portion 2, the temporal and masseter. 
 
 Mastoid Portion 6, the occipito-frontalis, sterno-cleido-mastoid, splen- 
 ius capitis, trachelo-mastoid, digastric, and retrahens aurem. 
 
 Petrous Portion 3, the tensor tympani, levator veli palatini (leva tor 
 palati) and stapedius. 
 
 Styloid Process 3, the stylo-glossus, stylo-hyoid, and stylo-pharyngeus. 
 
 THE SPHENOID BONE, (5, Fig. 8) 
 
 Position and Form. Wedged in between the bones of the skull ante- 
 riorly, it resembles a bat with out-stretched wings. It is named from the 
 Greek word <r^v, a wedge, enters into the formation of 5 cavities, 4 fossae, 
 3 fissures, and presents for description 
 
 Body of the Sphenoid Bone. Placed in the median line, cuboid in shape, 
 it presents on its UPPER SURFACE from before backward, the following 
 points, 
 
 Sphenoidal or Ethmoidal Spine (3), articulating with the ethmoid bone. 
 
 Smooth Surface, grooved for the olfactory nerves. 
 
 Sulcus Chiasmatis or Optic Groove, supporting the commissure of the 
 optic nerves. 
 
 Tuberculum Settee or Olivary Process, an olive-shaped eminence behind 
 the optic groove. 
 
 Middle Clinoid Processes, bounding the Sella Turcica in front. 
 
 Fossa Hypophyseos or Sella Turcica (16) (Turkish saddle), lodges the 
 hypophysis (pituitary body) and the circular sinus of the brain. 
 
THE SPHENOID BONE 23 
 
 Dorsum Sella (cantle of the saddle) (16), grooved for the 6th nerves. 
 Posterior Clinoid Processes (6), for attachment of the tentorium cere- 
 belli, grooved by the optic tracts. 
 
 FIG. 12. 
 
 Grooves, laterally, for the cavernous sinus and internal carotid artery. 
 POSTERIOR SURFACE is rough and quadrilateral (15) : it articulates with the 
 basilar process of the occipital bone, ossification being completed from 
 the 1 8th to the 2oth year of age. 
 
 FIG. 13. 
 
 ANTERIOR SURFACE is nearly vertical, and presents the 
 
 Sphenoidal crest, in the median line, articulating with the perpendicu- 
 lar plate of the ethmoid bone, and forming part of the nasal septum- 
 Openings of the Sphenoidal Sinuses (e), cavities in the body of the bone 
 which exist in adults, not in children. 
 
24 HUMAN ANATOMY 
 
 Sphenoidal Concha or Sphenoidal Turbinal Bones, which partially close 
 
 the sinuses, and articulate with the ethmoid and orbital processes of 
 
 the palate bones. 
 
 INFERIOR SURFACE helps to form the nasal fossae, and presents the 
 Rostrum (d), which articulates with a groove on the vomer. 
 Alar Grooves, on each side of the rostrum, for articulation with the 
 
 wings of the vomer. 
 
 Vaginal Processes, i on each side of the rostrum. 
 Pterygo-palatine Grooves, which, with the sphenoidal processes of the 
 
 palate bones, form the pterygo-palatine canals, for the transmission 
 
 of the pterygo-palatine arteries and nerves. 
 
 Greater Wings of the Sphenoid. Each wing presents on its CEREBRAL 
 SURFACE the following points, 
 
 Foramen Rotundum (8), for the maxillary division of the 5th nerve. 
 Foramen Ovale (9), for the mandibular division of the 5th nerve, the 
 
 small petrosal nerve, and small meningeal artery. 
 Foramen Vesalii, transmitting a small vein; often absent. 
 Foramen Spinosum (10), transmitting the middle meningeal artery 
 
 and veins, also sympathetic filaments from the cavernous plexus. 
 THE ORBITAL or ANTERIOR SURFACE assists in forming the external wall of 
 the orbit, the inferior orbital (spheno- maxillary) and superior orbital 
 (sphenoidal) fissures. It articulates with the frontal and malar 
 bones, and presents a 
 
 Notch, transmitting a branch of the ophthalmic artery. 
 Spine, for part of the lower head of the external rectus muscle. 
 External Orbital Foramina, transmitting nutrient arterial branches. 
 EXTERNAL SURFACE consists of an upper portion, the temporal, separated 
 by a ridge, the infra-temporal crest, from a lower portion, the spheno- 
 maxillary surface. It presents the following points, 
 Infra-temporal or Pterygoid Ridge, dividing the temporal fossa from 
 
 the spheno-maxillary. 
 Alar Spine of the Sphenoid (n), to which are attached the internal 
 
 lateral ligament of the lower jaw, and the laxator tympani muscle. 
 CIRCUMFERENCE is partly serrated for articulation with the temporal and 
 frcntal bones, and partly smooth for the anterior margin of the foramen 
 lacerum medium and the inferior margin of the superior orbital (sphe- 
 noidal) fissure, which margins it assists in forming. 
 
 Lesser Wings (i) of the Sphenoid, or the Processes of Ingrassias (a), 
 terminate internally in the Anterior Clinoid Processes (5); their anterior 
 borders articulate with the orbital plate of the frontal bone, the posterior 
 
THE SPHENOID BONE 25 
 
 are free, dividing the anterior cerebral fossa from the middle ones. Con- 
 nected intimately with each of these wings are the 
 
 Optic Foramen (4) , formed by the separation of its roots, and transmit- 
 ting the optic nerve and the ophthalmic artery. 
 
 Superior Orbital or Sphenoidal Fissure (7), or Foramen Lacerum 
 Anterius (g), is bounded above by the lesser wing, below by the 
 greater wing, and transmits the 3d, 4th, ophthalmic division of the 
 5th, and the 6th nerves, the ophthalmic vein, branches of the lacri- 
 mal and middle meningeal arteries, some filaments of the sympathetic 
 and a process of the dura mater. 
 
 Medial (Internal) and Lateral (External) Pterygoid Processes of the 
 Sphenoid. These wing-like processes descend, i on each side of the body, 
 and divide each into 2 thin, bony plates (/w), connected together anteriorly, 
 and presenting the 
 
 Pterygoid Fossa, between the plates posteriorly, the origin of the inter- 
 nal pterygoid muscle. 
 Scaphoid Fossa, at the base of the internal plate, serves as the origin of 
 
 the tensor veli palatini (tensor palati) muscle. 
 Hamular Process, a hook-like projection at the apex of the internal 
 
 plate, around which plays the tendon of the tensor palati muscle. 
 Canalis Pterygoideus or Vidian Canal (14), at the root of the process, 
 
 for the Vidian nerve and vessels. 
 
 Triangular Notch, at the end of the process, articulates with the tu- 
 berosity of the palate bone. 
 
 Development of the Sphenoid. By 14 or 1 6 centres, as follows, 2 for 
 the greater wings, 2 for the lesser wings, 2 for the anterior part of the body, 
 2 for the posterior part of the body, 2 for the medial (internal) pterygoid 
 processes, and 2 for the sphenoidal conchae (turbinal processes), 2 
 for the lingulae and 2 for the epipteric bones which usually join the tips 
 of the great wings. Ossification begins in the 2d fcetal month, and is 
 completed about the nth year, by the union of the turbinal processes 
 with the body. 
 
 Muscles attached to the Sphenoid. 12 pairs of muscles are attached 
 to the sphenoid bone, as follows: 
 
 Orbital muscles, 6 all except the inferior oblique of the eye. 
 
 Muscles of Mastication, 3 the temporal, external and internal ptery- 
 
 goids. 
 Also the superior constrictor, tensor palati, and laxator tympani, 3. 
 
26 HUMAN ANATOMY 
 
 THE ETHMOID BONE 
 
 General Characteristics. It is a spongy, light bone, depending from 
 the ethmoidal notch of the frontal, and from between its orbital plates. It 
 consists of a body and 2 lateral masses, and is named from the Greek 
 word r/0/zos, a sieve. 
 
 Points on its Body. The body (b) consists of a horizontal or cribriform 
 plate and presents the 
 
 Crista Galli (c) , or cock's comb, projecting 
 upward, for the attachment of the anterior 
 end of the falx cerebri. 
 Cribriform Plate (d), on each side of the 
 crista galli. It is concave for the olfac- 
 tory bulbs (/), and perforated for the 
 transmission of the olfactory nerves, the 
 nasal branch of the ophthalmic nerve, 
 and numerous small vessels. 
 Perpendicular Plate (a), assists to form 
 the nasal septum, is usually inclined to 
 one side, grooved for filaments of the olfac- 
 tory nerves, and has attached to it the car- 
 tilage of the nose. 
 
 Lateral Masses. They consist of a number of cellular cavities, and each 
 ^ne presents the following points, 
 
 Ethmoid Cells, the anterior opening by the infundibulum into the 
 
 middle meatus of the nose, the posterior into the superior meatus. 
 Orbital Plate (lamina papyracea, os planum) (h), helps to form the 
 inner wall of the orbit and is notched superiorly to form with the 
 frontal bone the two ethmoidal foramina, or grooves. 
 Uncinate, or Unciform Process, descends to articulate with the infe- 
 rior concha, or turbinal, and forms part of the inner wall of theantrum. 
 Superior Concha, or Turbinal Process (/),- is a subdivision of the 
 
 posterior part of the middle turbinal process. 
 
 Middle Concha, or Turbinal Process (g), is larger and more curved 
 than the superior. These processes bound the superior meatus of 
 the nose. 
 
 Articulations, Development, and Muscles. The ethmoid articulates 
 with 15 bones, viz. all those of the face except the malar, and the 
 frontal and sphenoid of the cranium. - It is developed by 3 centres, i for 
 each lateral mass, and i for the body, ossification being completed about 
 the 6th year. There are no muscles attached to it. 
 
THE MAXILLARY BONE 27 
 
 OSSA NASALIA OR NASAL BONES, (20, Fig. 8) 
 
 The Nasal are 2 small bones forming the bridge of the nose by articula- 
 tion with each other in the median line (4). From side to side they are 
 convex externally and concave internally, where they are grooved longi- 
 tudinally for the external branch of the naso-ciliary, or nasal nerve and 
 some small arteries. They are perforated about the 
 centre by a foramen (i), for a small tributary to the 
 facial vein. The superior border (2) articulates with 
 the nasal notch of the frontal bone; the inferior bor- 
 der (3) serves for the attachment of the lateral car- 
 tilage of the nose. The external border (5) articu- 
 lates with the nasal process of the maxilla; the in- 
 ternal border (4) with its fellow, with the nasal spine 
 of the frontal above and with the ethmoid bone below. 
 They are each developed by one centre of ossification, 
 and have no muscles attached to them except a few 
 fibres of the occipito-frontalis. 
 
 THE MAXILLA, (18, Fig. 8) 
 
 The Maxillae are 2 hollow bones, together forming the upper jaw. 
 Each bone consists of 4 processes, and a body which possesses interiorly 
 a large cavity, the sinus maxillaris, or antrum of Highmore. 
 
 Antrum of Highmore ja a tetrahedral oa_yjiy in the body of the bone, 
 whichjpj3ens into the middle meatus of the nose by an aperture which is 
 very small in the recent subject, admitting only a small probe. Its walls 
 are very thin, and are covered internally by mucous membrane. It pre- 
 sents~the 
 
 Aperture, partly closed by the articulation of the uncinate, or unciform 
 process of the ethmoid with the ethmoidal process of the inferior 
 turbinal, and that of the maxillary process of the palate with a 
 fissure in the maxilla; also by the maxillary process of the inferior 
 turbinal which hooks over the lower edge of the orifice. 
 Posterior Dental Canals, on the posterior wall of the cavity. 
 Processes, in its floor, formed by the alveoli of the ist and 2d molar 
 
 teeth, the roots of which occasionally perforate it. 
 Other Points presented by the body. The body has 4 surfaces, the 
 facial externally, the zygomatic posteriorly, the orbital superiorly, and an 
 internal surface forming part of the outer wall of the nose and the cavity 
 of the mouth. The anterior or facial surface presents the 
 
28 
 
 HUMAN ANATOMY 
 
 FIG. 
 
 Incisive Fossa (2), on the facial surface, above the incisor sockets, for 
 
 the origin of the depressor alae nasi muscle. 
 
 Canine Fossa (i), more externally, for the levator anguli oris muscle. 
 Infraorbital Foramen (3), above the canine fossa, transmitting the 
 infraorbital vessels and nerve, from the infraorbital canal in the orbital 
 surface of the bone. 
 
 Maxillary Tuberosity (7), articulates with the tuberosity of the palate 
 bone. The nasal surface presents 
 
 Conchal or Turbinal Crests, inferior 
 and superior, for articulation with 
 inferior and middle conchae, bound- 
 ing horizontal grooves which cor- 
 respond to the meati of the nose. 
 Vertical Grooves, on the inner sur- 
 face, one, the lacrimal, assisting 
 to form the nasal duct, the other, 
 pterygo-palatine, to form the ptery- 
 go-palatine, or posterior palatine 
 canal. 
 Rough Surface, for articulation with 
 
 the palate bone. 
 
 Orbital Surface, articulating with 
 the lacrimal, ethmoid, and palate 
 bones interiorly, partly bounding 
 
 the spheno-maxillary fissure exteriorly, and forming the lower mar- 
 gin of the orbit anteriorly. 
 
 Infraorbital Groove (n), along the orbital surface, ending in the infra- 
 orbital canal and foramen. (See above.) 
 Depression, for the origin of the inferior oblique muscle of the eye. 
 
 Processes of the maxilla are 4 in number, as follows: 
 MALAR or ZYGOMATIC PROCESS (4, 5), is triangular, looks outward from 
 
 the body, and is rough for articulation with the malar bone. 
 NASAL or FRONTAL PROCESS (8), is thin anteriorly and serrated superiorly 
 
 (12) for articulation with the nasal bone; posteriorly it is smooth and 
 
 articulates with the lacrimal. It presents the 
 
 Conchal or Turbinal Crests, superior and inferior, the former articu- 
 lating with the middle concha or turbinal process of the ethmoid 
 bone. 
 
 Outer Surface, gives origin to the orbicularis palpebrarum and levator 
 labii superioris alaeque nasi muscles, and the tendo oculi. 
 
THE LACRIMAL BONE 2Q 
 
 Lacrimal Groove, on the posterior border (9), helping to form the nasal 
 
 canal. 
 ALVEOLAR PROCESS (6), forms the curved line of the teeth, and presents 
 
 Alevoli, or sockets, for 8 teeth in the adult, 5 in the child. 
 PALATINE PROCESS, forms part of the floor of the nasal cavity, and the 
 roof of the mouth. It articulates with the vomer, the palate bone, 
 and with its fellow process, and presents the 
 
 Incisive Foramen, or Foramen of Stenson, leading into the anterior 
 palatine canal, for the terminal branches of the posterior palatine 
 arteries. 
 
 Foramina of Scar pa, 2, transmitting the naso-palatine nerves. 
 Groove, on the under surface, for the protection of the vessels and 
 
 nerves. 
 
 Orifice, of the posterior palatine canal, at the posterior end. 
 Nasal Crest, at the articulation of the two processes with the vomer. 
 Anterior Nasal Spine (10), the anterior extremity of the nasal crest. 
 Articulations and Development. The maxilla articulates with 9 
 bones, the frontal (12), ethmoid (14), vomer (13), nasal (15), lacrimal, 
 malar, palate, inferior turbinal, and opposite maxilla. It is developed 
 probably by 4 centres, i for the facial and nasal parts, another for the 
 orbital and malar, a 3d for the incisive, and a 4th for the palate portion. 
 
 Muscles attached to it, are n, viz. the orbicularis palpebrarum, and 
 levator anguli oris alaeque nasi, 2, to the nasal process; the levator labii 
 superioris, levator anguli oris, compressor naris, depres- 
 sor alae nasi, orbicularis oris, and inferior oblique of the 
 eye, 6, to the body; the buccinator, i, to the alveolar 
 process; the masseter, i, to the malar process; and 
 the external pterygoid, i, to the tuberosity. 
 
 THE OSSA LACRIMALIA OR LACRIMAL BONES 
 
 The Lacrimal are 2 small quadrilateral bones, situated 
 in the anterior part of the inner wall of the orbit. Each 
 bone presents a 
 
 Groove (3), on the external surface, forming part of the nasal canal. 
 
 Ridge (i), also externally, for attachment of the tensor tarsi muscle. 
 
 Furrow, internally, corresponding to the ridge on the external surface. 
 
 Hamular Process (2), projecting forwards around the nasaj canal. 
 
 Superior Border (8), articulates with the internal angular process of 
 the frontal bone. 
 
30 HUMAN ANATOMY 
 
 Inferior Border (9), articulates anteriorly with the lacrimal process 
 of the inferior turbinal bone. 
 
 Anterior Border (6), articulates with the nasal process of the maxilla. 
 
 Posterior Border (7), articulates with the orbital plate of the ethmoid 
 bone. 
 
 Internal Surface, closes the anterior ethmoidal cells. 
 
 Articulations, Development, and Muscles. The lacrimal articu- 
 lates with 4 bones, the frontal, ethmoid, maxilla, and inferior turbinal. 
 It is developed from i centre, and has but i muscle attached to it, the tensor 
 tarsi or Homer's muscle. 
 
 THE OSSA ZYGOMATICA, OR MALAR BONES, (14, Fig. 8) 
 
 The Malar or cheek bones are situated at the outer and upper part of the 
 face, aiding to form the cavities of the orbits and the temporal and 
 zygomatic fossae. Each bone presents 3 surfaces, 3 processes and 3 
 borders. 
 
 The Orbital surface (c) forming the lateral and front part of the orbit, 
 is concave laterally; it is bounded in front by the margin of the orbit (6) 
 and behind by the rough orbital border. About the 
 FIG. 1 8. middle of this surface is seen the orbital ends of the 
 Zygomatico-facial, or malar, canals. The Zygomatic, 
 or infratemporal surface forms the front end of the 
 zygomatic arch. The facial surface is subcutaneous and 
 is also known as the malar surface or malar tuberosity; 
 it presents the outer ends of the two small malar 
 canals. Orbital, or fronto-sphenoidal process (a) in 
 man, and those animals having a closed orbit, articu- 
 lates with the great wing of the sphenoid and the orbital process of the 
 frontal bone. It forms the upper end of the temporal border (h) which 
 forms the anterior boundary of the temporal fossa and is continuous with 
 the temporal ridge of the skull. This border terminates below and 
 behind in the zygomatic or temporal process (/), which is rough for ar- 
 ticulation with the zygomatic process of the temporal bone. The lower 
 or masseteric border (g) is rough for attachment of the masseter and 
 zygomatic muscles. It terminates medially in the long slender maxillary 
 process (d) which is very rough for articulation with the maxilla and 
 forms most of the lower margin of the orbit (&). 
 
 Articulations, Development, and Muscles. The malar articulates 
 with 4 bones, the frontal, sphenoid, temporal, and maxilla. It is 
 
THE PALATE BONES 3! 
 
 developed by one centre of ossification, and has 4 muscles attached to 
 it, the levator labii superioris, zygomaticus major and minor, and the 
 masseter. 
 
 THE PALATE BONES 
 
 The Palate Bones are 2 L-shaped bones, situated posteriorly in the 
 nares. Each bone assists in forming the floor and outer wall of the 
 nose, the roof of the mouth, the floor of the orbit, the inner wall of the an- 
 trum, the zygomatic, spheno-palatine, and pterygoid fossae, and presents 
 the following points : 
 
 HORIZONTAL PLATE (a), completes the nasal floor and hard palate; has a 
 Ridge, on the inferior surface, for the tensor palati aponeurosis. 
 Groove, assisting to form the posterior palatine canal. 
 Foramina, transmitting the anterior and posterior 
 
 palatine nerves. 
 Anterior Border, is serrated, for articulation with 
 
 the maxilla. 
 
 Posterior Border, is free and concave, for the at- 
 tachment of the soft palate. 
 
 Inner Border (d), is thick, and articulates with 
 
 its fellow, forming a groove for the reception 
 
 of the vomer. Its posterior extremity is the 
 
 Posterior Nasal Spine, for the origin of the azygo 
 
 uvulae muscle. 
 VERTICAL PLATE (6), a broad and thick lamella, pre- 
 sents the following: 
 
 Ridge for Middle Concha, on the inner surface. Below it is the 
 Ridge for Inferior Concha (g), dividing the middle meatus of the nose 
 from the inferior, and articulating with the inferior concha or turbinal 
 bone. 
 
 Posterior Border, articulates with the pterygoid process of the sphenoid. 
 Groove, on the external surface, helping to form the posterior palatine, 
 
 or pterygo-palatine canal. 
 
 Two Smooth S urfaces externally, one forming the inner wall of the 
 spheno-palatine or pterygo-palatine fossa; the other, part of the inner 
 wall of the maxillary antrum. 
 Two Rough Surfaces also externally, one for articulation with the 
 
 maxilla; the other with the pterygoid process of the sphenoid. 
 Deep Notch, which by articulation with the sphenoid bone, forms the 
 spheno-palatine foramen (A), for the spheno-palatine vessels and the 
 superior nasal and palatine nerves. 
 
32 HUMAN ANATOMY 
 
 TUBEROSITY OR PYRAMIDAL PROCESS (c), is wedged into the notch between 
 
 the plates of the pterygoid process of the sphenoid, with which it 
 
 articulates laterally. In it are the 
 
 Palatine Foramina, for the anterior, middle and posterior palatine 
 nerves. 
 
 Posterior Surface, aids in forming the pterygoid fossa. 
 ORBITAL PROCESS (*), triangular in shape, large and hollow. It has 
 
 Three Articular Surfaces, for the maxiJla, sphenoid, and ethmoid. 
 
 Two Free Surfaces, the orbital forming, part of the floor of the orbit, the 
 external aiding to form the spheno-palatine fossa. 
 
 Rounded Border, forms a part of the spheno-maxillary fissure. 
 SPHENOIDAL PROCESS (j), projects backward, articulates superiorly with 
 
 the body of the sphenoid, and externally with the pterygoid process of 
 
 the sphenoid. On its upper surface is a 
 
 Groove, which assists in forming the spheno-palatine or pharyngeal 
 canal. 
 
 Inner Surface, forms part of the outer wall of the nasal fossa. 
 
 Articulations, Development, and Muscles. The palate articulates 
 with 6 bones, the sphenoid, ethmoid, vomer, maxilla, inferior turbinal, 
 and its fellow palate bone. It is developed by one centre at the junction 
 of the two plates. There are 4 muscles attached to it, the azygos uvulae, 
 internal pterygoid, superior constrictor and tensor palati. 
 
 THE CONCH^E NASALES INFERIORES OR THE INFERIOR 
 TURBINAL BONES 
 
 The Inferior Turbinal Bones are 2 thin, curved osseous plates situated in 
 the nasal fossae, their convex surfaces presenting inwardly. Each bone is 
 p IG . 20. attached above to the inferior turbinal crests 
 
 of the maxillary and palate bones, and presents 
 the following, viz. 
 
 Lacrimal Process (3), aiding to form the 
 nasal duct, by articulation with the lacri- 
 mal and maxilla. 
 
 Ethmoidal Process (i), articulating with the unciform process of the 
 ethmoid, thus helping to partially close the aperture of the antrum. 
 Maxillary Process (4), also helps to partially close the aperture of the 
 
 maxillary antrum, by hooking (7) over the lower edge of that orifice. 
 Free Border (5), below, coming to about % inch above the floor of the 
 nose. 
 
THE VOMER AND MANDIBLE 33 
 
 Articulations, Development and Muscles. The inferior turbinal ar- 
 ticulates with 4 bones, the ethmoid, lacrimal, palate, and maxilla. It 
 is developed by one centre, and has no muscles attached to it. 
 
 THE VOMER 
 
 The Vomer (plough-share) forms the postero-inferior part of the nasal 
 septum, but is usually bent to one side. Its 
 
 Superior Border (i, 2), has a groove and two alae or wings, for articula- 
 tion with the rostrum and vaginal proc- 
 esses of the sphenoid bone. 
 Anterior Border (3), is grooved for the 
 
 ethmoidal plate and the jiasal cartilage. 
 Inferior Border (4), the longest, articulates 
 with the nasal crest of the maxillary and 
 palate bones. 
 
 Posterior Border, is free and presents toward the pharynx. 
 Naso-palatine Grooves, laterally, for the naso-palatine nerves. 
 Furrows, on the lateral surfaces (6), for vessels and nerve-filaments. 
 Articulations, Development and Muscles. The vomer articulates 
 with 6 bones, the sphenoid, ethmoid, 2 maxillary, and 2 palate bones. 
 It is developed by one centre, which appears about the 6th foetal week in 
 cartilage between two laminie which coalesce after puberty. It has no 
 muscles attached to it. 
 
 THE MANDIBLE, (25, Fig. 8) 
 
 General Characteristics. The Mandible is the lower jaw, receives the 
 inferior teeth, and is the second bone of the body in which ossification 
 appears, the clavicle being the first. It consists of a body and two rami. 
 
 The Body (i) is shaped somewhat like a horseshoe, and presents for 
 examination the following: 
 
 Alveolar Portion (15), above the oblique line, containing on its upper 
 border alveoli for 16 teeth in the adult, for 10 in the child (i, b, c, m). 
 Symphysis (3), a vertical ridge on the median line, marking the junc- 
 tion of the two symmetrical portions of which the bone originally 
 consisted. 
 Mental Process, a prominent triangular eminence, characteristic of 
 
 man, forming the chin. 
 
 Externally on each side from the symphysis backward, are the 
 3 
 
34 HUMAN ANATOMY 
 
 Incisive Fossa (4), above the chin, for the origin of the levator menti. 
 Meatal Foramen (5), below the 2d bicuspid alveolus, transmitting the 
 
 mental artery and nerve. 
 
 External Oblique Line (i), for the origins of the depressor labii infe- 
 p IG 22 rioris and depressor anguli 
 
 oris muscles from its anterior 
 half. 
 Groove (7), near the angle, 
 
 for the facial artery. 
 Internally, on each side from the 
 median depression backward, 
 are the 
 
 Mental Spines, or Genial Tuber- 
 cles, the superior for the 
 genio-hyoglossus muscle; the 
 inferior for the genio-hyoid. 
 Mylo-hyoid Ridge, obliquely backward, for the mylo-hyoid muscle. 
 Sublingual Fossa, near the genial tubercles, for the sublingual gland. 
 Fossa, below the sublingual, for the anterior belly of the digastric 
 
 muscle. 
 Submandibular Fossa, below the ridge, for the submandibular gland. 
 
 The Rami of the Mandible, the ascending portions of the bone, are 2 
 in number, and each presents the 
 
 Coronoid Process (10), anteriorly, for the insertion of the temporal 
 
 muscle. 
 Condylar Process (n), posteriorly. Its condyle articulates with the 
 
 glenoid fossa of the temporal bone, its neck receives the insertion of the 
 
 external pterygoid muscle, its tubercle has attached to it the external 
 
 lateral ligament of the lower jaw. 
 Sigmoid Notch (12), a deep depression separating the above-named 
 
 processes from each other, and crossed by the masseteric vessels 
 
 and nerve. 
 Groove, on the coronoid process internally, and prolonged downward 
 
 upon the body, for the attachment of the buccinator muscle. 
 Ridges, on the external surface, for the insertion of the masseter. 
 Lingula or Spix's Spine, a projection on the margin of mandibular 
 
 foramen, for the attachment of the spheno-mandibular ligament. 
 Mandibular Foramen, or Canal (13), opening behind the spine, lies 
 
 within the ramus and body of the bone for the inferior dental vessels 
 
 and nerve. It communicates with each alveolus and with the 
 
 mental foramen. 
 
THE ORBITS 35 
 
 Mylo-hyoid Groove (14), below the spine, for the mylo-hyoid vessels and 
 
 nerve. 
 
 Rough Surface, behind the groove, for the internal pterygoid muscle. 
 Angle of the Jaw (8), at the junction of the posterior border of the 
 
 ramus with the inferior border of the body, for the insertion of the 
 
 masseter and internal pterygoid muscles, and the stylo-mandibular 
 
 ligament. 
 
 Articulations and Development. It articulates with one pair of bones, 
 the temporal. It is the earliest formed bone in the body except the 
 clavicle, and is probably developed by 2 centres, one for each lateral half, 
 the two halves coalescing at the symphysis about the ist year of age. 
 In adult life the ramus arises almost vertically from the body, and the 
 dental canal lies about the middle of the body. In old age the ramus 
 seems to extend obliquely backward, the angle becoming very obtuse; 
 and the alveolar portion being absorbed, the dental canal is near the 
 superior border. 
 
 Muscles attached to the Mandible, number 15 pairs, the masseter, 
 internal and external pterygoids and temporal, 4, to the ramus; the 
 genio-hyo-glossus, genio-hyoid, mylo-hyoid, digastric, and superior con- 
 strictor, 5, to the internal surface of the body; the depressor labii inferioris, 
 depressor anguli oris, levator menti, orbicularis oris, platysma myoides, 
 and buccinator, 6, to the external surface of the body. 
 
 'M T - E ORBITS 
 
 The Orbits are 2 conoidal cavities, situated between the forehead and 
 the face, their bases outward, their apices pointing backward, the lines of 
 axial prolongation meeting at the sella turcica of the sphenoid bone. They 
 contain the organs of vision with their appendages, and are each formed 
 by 7 bones, the frontal (i), ethmoid (2), sphenoid (3, 4, 5), lacrimal 
 (6), maxilla (7), palate (8), and malar (9), of which the first three are com- 
 mon to both orbits. Each orbit communicates with i cavity and 4 fossae, 
 as follows, viz. 
 
 Cavity of the cranium, by the optic foramen (u) and superior orbital 
 
 or sphenoidal fissure (10). 
 
 Fossa (4), the nasal, temporal, zygomatic, and spheno-palatine or 
 spheno-maxillary, by the nasal duct (12) and the inferior orbital or 
 spheno-maxillary fissure (13). 
 
 Foramina communicating with each orbit are 9 in number, the optic 
 foramen (u), superior orbital or sphenoidal fissure (10), anterior (21) and 
 
36 
 
 HUMAN ANATOMY 
 
 FIG. 23. 
 
 posterior (22) ethmoidal foramina, supraorbital (14), infraorbital (15), 
 and zygomatico-facial and temporal or malar foramina (16), the nasal 
 or lacrimal canal (12), and the inferior orbital or spheno-maxillary 
 fissure (13). 
 
 Roof of the Orbit is formed by the orbital plate of the frontal bone ante- 
 riorly (i), and the lesser wing of the sphenoid (4) posteriorly. It is con- 
 cave, and presents the 
 
 Lacrimal Fossa (17), at its outer angle, for the lacrimal gland. 
 
 Fovea Trochlearis (18), at the 
 inner angle, for the pulley 
 of the superior oblique. 
 Floor of the Orbit is formed 
 by the orbital surface of the 
 maxilla (7), and the orbital 
 process of the malar (9) and pal- 
 ate bones (8). 
 
 It is nearly flat and presents the 
 Palato-maxillary Suture, pos- 
 teriorly. 
 
 Infraorbital Canal, anteriorly. 
 Infraorbital Groove (9), pos- 
 teriorly. 
 
 Medial or Inner Wall of the 
 Orbit is formed by the nasal 
 process of the maxilla (20), the 
 
 lacrimal (6), the orbital plate or lamina papyracea of the ethmoid (2), 
 and the body of the sphenoid (3). It presents 
 
 A Groove, for the lacrimal sac, and the Lacrimal Crest, anteriorly. 
 2 Sutures, the ethmo-lacrimal, and the ethmo-sphenoidal. 
 
 Lateral or Outer Wall of the Orbit is formed by the orbital process of the 
 malar bone (9), and the greater wing of the sphenoid (5). It presents the 
 Orifices (16) of the zygomatico-facial and zygomatico- temporal or malar 
 canals, and the Spheno-malar Suture. 
 
 Angles of the Orbit present the following points: 
 
 IN THE SUPERIOR EXTERNAL ANGLE: 
 
 Superior Orbital or Sphenoidal Fissure (10), or Foramen Lacerum 
 Anterius, transmits the 3d, 4th, ophthalmic division of the 5th, 
 and the 6th nerves, the ophthalmic vein, branches of the lacrimal 
 
THE FOSS.E OF THE SKULL 37 
 
 and middle meningeal arteries, filaments of the sympathetic nerve, 
 and a process of the dura mater. 
 Articulations, the fronto-malar, and fronto-sphenoidal. 
 
 IN THE SUPERIOR INTERNAL ANGLE: 
 
 Suture, the lachrymo-ethmo-frontal, in which are the following fora- 
 mina: 
 
 Anterior Ethmoidal Foramen (21), transmitting the anterior ethmoidal 
 artery and the nasal nerve. 
 
 Posterior Ethmoidal For amen (22), transmitting the posterior ethmoidal 
 artery and vein. 
 
 IN THE INFERIOR EXTERNAL ANGLE: 
 
 Inferior Orbital or Spheno-maxittary Fissure (13) (described under the 
 Zygomatic Fossa). 
 
 IN THE INFERIOR INTERNAL ANGLE: 
 
 A Suture, the ethmo-maxillo-palato-lacrimal. 
 
 Other Points connected with the Orbit are two, the supraorbital notch 
 and the optic foramen, as follows: 
 
 Supraorbital Notch or Foramen (14), at the junction of the inner and 
 middle thirds of the upper circumference, transmitting the supra- 
 orbital artery, veins, and nerve. A line prolonged from this notch 
 through the interval between the bicuspid teeth of either jaw, will 
 cross both the infraorbital and mental foramina, and the canine fossa 
 of the maxilla. 
 
 Optic Foramen (n), at the apex, is formed by the 2 roots of the lesser 
 wing of the sphenoid, and transmits the optic nerve and the ophthal- 
 mic artery. From around its margin arises a tendinous ring, the 
 common origin of the 4 recti muscles of the eye. 
 
 Muscles arising within the Orbit are the 4 recti and 2 oblique of the eye, 
 the levator palpebrae, and the tensor tarsi (8 in all). 
 
 THE FOSSJE 
 
 The Nasal Fossae together form the cavity of the nose, being separated 
 from each other by the Septum Nasi (n). They open in front by the 
 anterior nares, behind by the posterior nares; and extend from the palate 
 processes of the maxilla and palate bones (17), upward to the base of the 
 cranium. They are formed by 14 bones, the ethmoid, sphenoid, 
 frontal, vomer, 2 nasal, 2 maxillae, 2 lacrimal, 2 palate and 2 inferior con- 
 chae or turbinal. 
 
 The Septum Nasi (n) forms the inner wall of each nasal fossa, and is 
 formed chiefly by the perpendicular plate of the ethmoid bone, the vomer. 
 
38 HUMAN ANATOMY 
 
 and the triangular cartilage of the septum; to a less extent by 5 other bones, 
 the rostrum of the sphenoid, the nasal spine of the frontal, and the crests 
 of the nasal, palate, and maxillary bones. 
 
 Points presented by each Nasal Fossa are as follows: 
 ON THE ROOF : 
 
 Openings, posteriorly, into the sphenoidal sinuses. 
 
 Olfactory Foramina, and the Nasal Slit, -in the cribriform plate of the 
 
 ethmoid bone. 
 ON THE FLOOR: 
 
 Orifice, of the anterior palatine canal. 
 
 Suture, between the bones forming the hard palate. 
 
 Nasal Spine, anterior and posterior, and the Ridge connecting them. 
 
 ON THE LATERAL OR OUTER WALL, 
 
 FIG. 24. from above downward: 
 
 Superior Concha or Turbinal 
 
 Process, of the ethmoid. 
 Superior Meatus of the nose 
 into which open 3 orifices, 
 those of the posterior eth- 
 moidal and the sphenoidal 
 sinuses, and the sphenopala- 
 tine foramen. 
 
 Middle Concha or Turbinal 
 Process (7), of the ethmoid. 
 Middle Meatus of the nose, 
 into which open 2 orifices, 
 those of the antrum (14) and 
 
 infundibulum, the latter draining the anterior ethmoidal cells (8), 
 and the frontal sinus. 
 
 Inferior Concha or Turbinal Bone (10), below which is the 
 Inferior Meatus of the nose, the largest; into it open 2 orifices, those 
 of the lacrimal and anterior palatine canals. To these may be 
 added the apertura pyraformis (anterior) and posterior nares. 
 
 The Temporal Fossa. Situated on each side of the cranium, it is shallow 
 above and behind, but deep in front and below, and is formed by parts 
 of 5 bones, the frontal, sphenoid, temporal, parietal, and malar. It is 
 bounded above and behind by the temporal ridge, in front by the malar, 
 frontal, and sphenoid bones, and below by the zygoma and the pterygoid 
 bounded above and behind by the temporal ridge, in front by the malar, 
 frontal, and sphenoid bones, and below by the zygoma and the pterygoid 
 
SUTURES AND FONTANELLES 39 
 
 ridge on the greater wing of the sphenoid. It is traversed by 6 sutures, 
 the spheno-malar, spheno-frontal, spheno-parietal, spheno-temporal, 
 frontal-parietal, and temporo-parietal. It opens below into the zygomatic 
 fossa; and lodges the temporal muscle, and the deep temporal vessels. 
 
 The Zygomatic Fossa extends downward from the temporal fossa, and 
 is bounded 
 
 In front, by the tuberosity of the maxilla. 
 
 Laterally or Externally, by the zygoma, and the ramus of the mandible. 
 
 Medially or Internally, by the lateral or external plate of the pterygoid 
 
 process. 
 Above, by the temporal fossa, the squamous portion of the temporal 
 
 bone and the greater wing of the sphenoid. 
 Below, by the alveolar border of the mandible bone. 
 
 Fissures opening into the Zygomatic Fossa are two, the 
 Inferior Orbital or Spheno-maxillary Fissure, between the greater wing 
 of the sphenoid externally, and the maxilla and palate bones medially 
 or internally. It connects the orbit with the zygomatic, temporal, and 
 spheno-palatine fossse; and transmits the infraorbital artery, the maxil- 
 lary nerve and its orbital branches, and the ascending branches of 
 Meckel's ganglion. 
 
 Pterygo-maxillary Fissure, between the tuberosity of the maxilla and 
 the pterygoid process of the sphenoid. It transmits branches of 
 the internal maxillary artery, and connects the zygomatic fossa with 
 the spheno-palatine. 
 
 The Spheno-palatine Fossa is a triangular cavity between the pterygoid 
 process of the sphenoid bone and the tuberosity of the maxilla, and is 
 situated at the junction of the spheno-maxillary, pterygo-maxillary, and 
 sphenoidal fissures. Into it open 
 
 3 FOSSCE, the orbital, zygomatic, and nasal. 
 2 Cavities, the cranial, and buccal. 
 
 5 Foramina, the Vidian and spheno-palatine or pharyngeal canals and 
 the foramen rotundum, posteriorly; the spheno-palatine foramen on 
 the inner wall; and the posterior palatine canal interiorly, occasion- 
 ally also the accessory palatine canals. 
 
 THE SUTURES AND FONTANELLES 
 
 The Sutures of the Skull are 13 in number, as follows: 
 At the vertex of the skull are 3, the 
 
40 HUMAN ANATOMY 
 
 Sagittal or Interparietal, formed by the junction of the two parietal 
 
 bones. 
 Metopic, between the halves of the Frontal, may persist until late in 
 
 life. 
 Coronal or Fronto-parietal, extends transversely across the vertex 
 
 of the skull anteriorly. 
 Lambdoid or Occipito-parietal, extends transversely across the vertex 
 
 of the skull posteriorly. 
 At the sides of the skull are 5, the 
 
 Fronto-malar and Fronto-sphenoidal, anteriorly. 
 Spheno- parietal, Squamo- parietal and Masto- parietal, posteriorly. 
 At the base of the skull are 5, the 
 
 Basilar, in the central line of the base. 
 
 Petro-occipital, Masto-occipital, Petro-sphenoidal and Squamo- sphenoidal 
 
 on each side. 
 
 The Facial Sutures are very numerous, the most important being the 
 following: 
 
 Zygomatic Suture, at the temporo-malar articulation. 
 
 Transverse Suture, extending from one external angular process of 
 the frontal bone across to the other, and connecting that bone with 
 the malar, sphenoid, ethmoid, lacrimal, maxillary, and nasal bones. 
 
 Symphysis of the Chin, the site of a fcetal suture. 
 
 The Sutures are formed by dentations of the external tables inter- 
 digitating with each other, the adjacent edges of the internal tables lying 
 in unjoined proximity. The sutures are not formed until a long time 
 after the formation of the skull, probably to permit of the marginal growth 
 of the bones. 
 
 The Fontanelles are 6 membranous intervals in the infant's skull, 
 corresponding in situation with the angles of the two parietal bones. 
 They are as follows: 
 
 Anterior, at the junction of the sagittal and coronal intervals. 
 
 Posterior, at the junction of the sagittal and lambdoid intervals. 
 
 Lateral Fontanelles, 4, two at the anterior inferior angles, and two at 
 the posterior inferior angles of the parietal bones. 
 
 The Ossa Suturarum (Wormian Bones) are supernumerary small pieces 
 of bone, irregularly shaped, and developed by special centres in unclosed 
 portions of the cranial sutures and fontanelles, being most frequent in the 
 lambdoid suture. 
 
FORAMINA AT BASE OF SKULL 4! 
 
 The Hyoid Bone is shaped like a horse-shoe and has no articulation with 
 the skeleton, but supports the tongue. It consists of a Body, two greater 
 and two lesser Cornua or horns. On the body is a Crucial Ridge, with a 
 Tubercle at the centre. It is developed by 5 centres, one for the body 
 and one for each horn. Attached to it are 10 muscles, 3 ligaments and i 
 membrane, as follows: 
 
 To the Body or Basi-hyal, the genio-, mylo-, stylo-, sterno-, thyro-, 
 omo-hyoid, the genio-hyo-glossus, and the hyo-glossus muscles; also 
 the pulley of the digastric, the hyo-epiglottic ligament, and the thyro- 
 hyoid membrane. 
 
 To the Greater Cornu, or thyro-hyal, the hyo-glossus, middle constrictor 
 muscles, and part of the thyro-hyoid; also the thyro-hyoid ligament. 
 To the Lesser Cornu, or cerato-hyal, the stylo-hyoid ligament. 
 
 FORAMINA AT THE BASE OF THE SKULL 
 
 with the various structures transmitted by each foramen 
 
 Internally, the Anterior Fossa has i single and 4 pairs, viz. 
 
 , Foramen Cacum, lodges a fold of dura mater, and transmits a vein to 
 
 the longitudinal sinus. 
 
 Ethmoidal Fissure, the nasal branch of the 5th nerve. 
 Olfactory, olfactory nerves, and nasal branches of the ethmoidal 
 
 arteries. 
 Anterior Ethmoidal, ant. ethmoidal artery and the nasal br. of the 5th 
 
 nerve. 
 Posterior Ethmoidal, posterior ethmoidal artery and vein. 
 
 Middle Fossae contain 10 foramina in each fossa, viz. 
 / Optic Foramen, optic nerve and ophthalmic artery. 
 r j Foramen Lacerum Anterius, Superior Orbital or Sphenoidal Fissure, the 
 3d, 4th, ophthalmic division of the 5th, and the 6th cranial nerves and 
 filaments of the sympathetic; ophthalmic vein, a branch of the 
 lacrimal artery, orbital branches of the middle meningeal artery, 
 and a process of dura mater. 
 
 Foramen Rotundum, maxillary division of the 5th nerve. 
 foramen Vesalii, a small vein. This foramen is often absent. 
 Foramen Ovale, mandibular division of the 5th nerve, lesser petrosal 
 nerve, and the small meningeal branch of the internal maxillary artery. 
 Foramen Spinosum, middle meningeal artery, meningeal veins, and 
 
 sympathetic filaments from the cavernous plexus. 
 Foramen Lacerum Medium, is not a true foramen in that it is completely 
 
42 HUMAN ANATOMY 
 
 blocked by fibro-cartilage, the cerebral surface of this cartilage is 
 deeply grooved or may even be tunneled from behind forwards 
 by internal carotid artery, carotid plexus, Vidian nerve, and artery. 
 
 Small Foramina, for the small and external superf. petrosal nerves. 
 
 Hiatus Canalisfacialis Fallopil, large petrosal nerve, and a branch of 
 middle meningeal artery. 
 
 Posterior Fossa contains 6 pairs and i single foramen, viz. 
 
 Meatus Acusticus or Auditor ins Intermts, facial and auditory nerves, 
 auditory artery. 
 
 Aqu&ductus Vestibuli, small artery and vein, process of dura mater. 
 
 Foramen Lacerum Posterius (Jugular Foramen) , the glosso-phary ngeal, 
 pneumo-gastric, and spinal accessory nerves, internal jugular vein, 
 meningeal branches of the ascending pharyngeal and occipital 
 arteries. 
 
 ; Mastoid Foramen (often absent), a small vein, also occasionally the 
 mastoid artery. 
 
 Anterior Condylar or Hypoglossal Foramen, hypoglossal nerve, menin- 
 geal branch from the ascending pharyngeal artery. 
 
 Posterior Condylar Foramen (often absent), posterior condylar vein. 
 
 Foramen Magnum, medulla oblongata and its membranes, the vertebral 
 arteries, and the spinal accessory (n. accessorius) nerves. 
 
 Externally, at the base of the skull, from the front backward, are 22 fora- 
 mina on each side, and i single, the foramen magnum, as follows: 
 
 Foramina of Scar pa (2) (Anterior Palatine), 2 in the median line, for 
 the naso-palatine nerves. 
 
 Foramina of Stenson (2) (Incisive}, laterally, terminal branches of the 
 posterior palatine arteries. 
 
 Posterior Palatine (3), posterior palatine vessels, anterior palatine 
 nerve. 
 
 Accessory Palatine Foramina (i or 2 on each side), the middle and pos- 
 terior (small) palatine nerves. 
 
 Orifice of the Posterior Naris, air to the lungs. 
 
 Ptery go- palatine Foramen, pterygo-palatine vessels. 
 
 Foramen Ovale (10), mandibular nerve. 
 
 Orifice of the Vidian or Pierygoid Canal, the Vidian nerve and vessels. 
 
 Foramen Spinosum (n), middle meningeal artery. 
 
 Foramen Lacerum Medium (12), see under Middle Fossae. 
 
 Opening for the Eustachian Tube. SLIT to the middle ear. 
 
 Opening of Tensor Tympani Canal, the tensor tympani muscle. 
 
TKE BASILAR SURFACE OF SKULL 
 
 43 
 
 Glaserian Fissure, laxator tympani muscle, tympanic artery; lodges the 
 
 processus gracilis of the malleus. 
 Carotid Foramen (19), internal carotid artery, nerves from the superior 
 
 cervical ganglion to the carotid plexus. 
 
 Anterior Condylar or Hypoglossal Foramen, Hypoglossal nerve. 
 Foramen Lacerum Poster ins (20), see under Posterior Fossa. 
 
 PIG. 25. 
 
 Foramen for Jacobson's Nerve, tympanic branch of the glosso-pharyn- 
 
 geal. 
 
 Foramen for Arnold's Nerve, auricular branch of the pneumogastric. 
 Opening of the Aquaduclus Cochlea, artery and vein to the cochlea. 
 Stylo-mastoid Foramen (18), facial nerve, stylo-mastoid artery. 
 Auricular Fissure, exit of Arnold's nerve, auricular branch of the 
 
 vagus. 
 
44 HUMAN ANATOMY 
 
 Posterior Condylar Foramen, see under Posterior Fossa. 
 Foramen Magnum (23), see under Posterior Fossa. 
 
 Face presents 4 pairs, viz. 
 
 Supraorbital Foramen or Notch, supraorbital artery, vein, and nerve. 
 Infraorbital Foramen, inf raorbital artery, vein and nerve. 
 Orifice of the Anterior Naris or Apertura pyraformis, air to the lungs. 
 Mental Foramen, mental nerve and artery. 
 
 POINTS AT THE BASE OF THE SKULL 
 
 illustrated and numbered on fig. 25 
 
 Median Suture (i), of the palatine vault, crucial in form posteriorly. 
 
 Posterior Nasal Spine (4), the posterior border of the palatine vault. 
 
 Vomer (5), or nasal septum, its posterior border. 
 
 Hamular Process (6), of the pterygoid process of the sphenoid bone. 
 
 Internal Plate (7), of the pterygoid process of the sphenoid bone. 
 
 External Plate (8), of the pterygoid process of the sphenoid bone. 
 
 Scaphoid Fossa (9), on the internal plate (7) of the pterygoid process. 
 
 Zygoma (13), or zygomatic process of the temporal bone. 
 
 Basilar Suture (14), between the occipital and sphenoid bones. 
 
 Basilar Process (22), of the occipital bone. 
 
 Articular or Clenoid Fossa (15), for the mandible. 
 
 Glaserian Fissure, squamo-tympanic. 
 
 External Auditory Meatus (16). opening of the ext. auditory canal. 
 
 Mastoid Process (17), of the temporal bone. 
 
 Styloid Process (18), of the temporal bone. 
 
 Occipital Condyles (21), articulate with the atlas. 
 
 External Occipital or Nuchal Crest (24), terminating at the protuberance. 
 
 Inferior Nuchal or Curved Li.ies (25), of the occipital bone. 
 
 BONES OF THE EXTREMITIES 
 THE SHOULDER 
 
 Bones forming the Shoulder are the clavicle and scapula connecting the 
 arm with the trunk, and in this respect homologous to the innominate bone 
 in the lower part of the body, being sometimes called the shoulder girdle t 
 as the innominate bones arc called the pelvic girdle. 
 
CLAVICLE AND SCAPULA 45 
 
 The Clavicle, collar- or key-bone, is a short bone by structure, having no 
 medullary canal. It is curved like the letter/, its inner two-thirds being 
 prismatic and convex anteriorly; its outer third flattened, and concave 
 anteriorly. It is placed horizontally between the sternum and the 
 scapula and is the most elastic bone 
 in the body. It presents, from 
 within outward, the following points, 
 viz. 
 
 Facets (6), for articulation with 
 the sternum and the cartilage of 
 the 1st rib, at its sternal end. 
 
 Upper border extending the length of the medial two-thirds, rough at its 
 sternal end for attachment of the sterno-cleido-mastoid. Laterally it 
 becomes lost on the smooth flat upper surface of the acromial third. 
 UNDER SURFACE PRESENTS: 
 
 Impression (2), for the rhomboid, or costo-clavicular ligament. 
 
 Groove (i), on the lower surface, for the subclavius muscle. 
 
 Tubercle, for the conoid part of the costordavicular ligament. 
 
 Oblique Line, for the trapezoid part of the same ligament. 
 
 Facet (7), on the acromial end, for articulation with the scapula. 
 
 Nutrient For amen, in the subclavian groove or in posterior surface, and 
 runs towards the shoulder. 
 
 Anterior Border (5), Medial two-thirds convex forwards and rough for 
 attachment of pectoralis major. Lateral third is concave forwards, 
 presents deltoid tubercle and is rough for attachment of deltoid. 
 
 Posterior Border (4), medial two-thirds concave and not well-defined, 
 acromial third is con vex back wards and rough for attachment of thetrape- 
 zius. Medial two-thirds ossify from cartilage, lateral third from membrane. 
 
 The Scapula, or shoulder-blade, is a large, flat, and triangular bone, 
 situated on the posterior and lateral portion of the thorax, from the 2d rib 
 to the 7th, inclusive. Its 
 VENTER, or anterior surface, presents from within outward, 
 
 Ridges, giving attachment to the subscapularis muscle. 
 
 Marginal Surface, along the inner border for the attachment of the 
 serratus magnus muscle. 
 
 Subscapular Fossa and Angle, for the subscapularis muscle. 
 DORSUM, or posterior surface, presents the following, viz. 
 
 Spine (10), a bony ridge, which affords attachment to the trapezius 
 and deltoid muscles, and ends in the acromion process. 
 
 Supraspinous Fossa (i), above the spine, for the^supraspinatus muscle. 
 
HUMAN ANATOMY 
 
 Infraspinous.Eossa (2), below the spine, larger than the supraspinous, 
 convex at its centre, lodges the infraspinatus muscles, and the 
 nutrient foramen. 
 
 Marginal. Surf ace, along the external border, to which are attached 
 
 the teres minor muscle above, the 
 teres major below, and sometimes 
 a few fibres of the latissimus dorsi 
 at the lower angle. 
 Groove, crossing the margin, for the 
 
 dorsalis scapulae vessels. 
 Smooth Surface (n), behind the 
 root of the spine, over which the 
 trapezius muscle glides. 
 ACROMION PROCESS (12), or summit of 
 the shoulder, extends from the spine, 
 and projects over the glenoid cavity, 
 articulating with the clavicle by an 
 oval facet. It affords attachment to 
 the deltoid and trapezius muscles, and 
 by its apex to the coraco-acromial 
 ligament. 
 
 CoRACpip PROCESS (14), or crow's beak, 
 projects from the upper border and 
 
 neck of the bone over the inner and upper part of the glenoid cavity. 
 Into it is inserted i muscle, the pectoralis minor; the coraco-brachialis 
 and the short head of the biceps arise from it by a common tendon, 
 and 3 ligaments are attached to it, the conoid, trapezoid, and 
 coraco-acromial. 
 
 SUPERIOR BORDER (3) presents the 
 
 Suprascapular Notch (4), converted into a foramen for the supra- 
 scapular nerve by the transverse ligament, over which passes the 
 suprascapular, or transverse scapular artery. The omo-hyoid 
 muscle is attached to the border just internal to this notch. 
 AXILLARY BORDER (5) is the thickest, and presents a 
 
 Rough Surface (8), for the long head of the triceps muscle just below 
 
 the glenoid cavity. 
 
 Notch, for circumflex scapular artery. 
 Groove, the origin of a part of the subscapularis muscle. 
 VERTEBRAL BORDER (9) is the longest, and presents an 
 Anterior Lip, for the attachment of the serratus magnus. 
 Posterior Lip, for the supra- and infraspinatus muscles. 
 
THE HUMERUS 47 
 
 Interspace, between the lips, for the levator anguli scapulae, the rhom- 
 boideus minor, and the fibrous arch of the rhomboideus major 
 muscles. 
 OTHER POINTS of interest on the bone are the 
 
 Medial, or Superior Angle, affords attachment to part of the serratus 
 magnus, levator anguli scapulae, and supraspinatus muscles. 
 
 Inferior Angle (7), affords attachment to part of the serratus magnus 
 and teres major muscles, and to a few fibres of the latissimus dorsi. 
 
 Glenoid Cavity (6), at the external angle or head of the bone, a shallow 
 cavity for the reception of the head of the humerus. It is deepened 
 by the glenoid ligament which is attached around its margin; and 
 gives origin to the long head of the biceps flexor cubiti muscle. 
 
 Neck, is the contracted part of the bone behind the glenoid cavity; 
 from it arises the anterior root of the coracoid process. 
 
 THE ARM 
 
 The Humerus is the only bone in the arm, and articulates with the 
 scapula above, and with the ulna and radius below. It presents for 
 examination a shaft and two extremities, on which are the following 
 points, viz. 
 
 Head (b), is nearly hemispherical, and smooth for articulation with 
 the glenoid cavity of the scapula. 
 
 Anatomical Neck'(c), is a constriction in the bone, just below the head, 
 for the attachment of the capsular ligament. 
 
 Greater Tuber osity, or Tubercle (d), has 3 small facets for the inser- 
 tions of the supraspinatus, infraspinatus, and teres minor muscles. 
 
 Lesser Tuberosity, or Tubercle (e), on the inner side of the bone, gives 
 insertion to the subscapularis muscle. 
 
 Bicipital, or Intertubercular Groove (/), lies vertically between the 
 tuberosities for the upper third of the bone and lodges the tendon 
 of the long head of the biceps flexor cubiti. Into its inner or medial 
 lip (h) are inserted the teres major and latissimus dorsi muscles, 
 while its outer or lateral lip (g) receives the insertion of the tendon 
 of the pectoralis major, which covers the groove. 
 
 Surgical Neck, is situated immediately below the tuberosities, and is 
 a slight constriction in the upper part of the shaft. 
 
 Shaft (a), is cylindrical above, prismatic and flattened below. 
 
 Rough Surface (i), for the insertion of the deltoid muscle, about the 
 middle of the external surface of the shaft. 
 
 Musculo-spiral Groove, or Sulcus n. Radialis (a), lodging the musculo- 
 spiral, or radial, nerve and the superior profunda artery, is situated 
 
HUMAN ANATOMY 
 
 on the posterior surface of the shaft, separating the origins of tne 
 outer and inner heads of the triceps muscle. 
 
 FIG 28 Orifice (j), of the nutrient canal, about the middle oi 
 
 the shaft, on its internal border. 
 
 Condylar Ridges, internal or medial (/>) and external 
 or lateral (0), arising from the respective condyles. 
 extending upward along the shaft. 
 
 Lateral or External Condyle (m),- -gives attachment to 
 the external lateral ligament and the extensor and 
 supinator group of muscles. 
 
 Medial or Internal Condyle (), lower and more promi- 
 nent lhan the other, gives attachment to the internal 
 lateral ligament and the flexor and pronator group of 
 muscles of the forearm. 
 
 Capitellum (&), forms the outer or lateral part of the 
 inferior articular surface; for articulation with the 
 radius, it is on the front of the lateral condyle, above it 
 is the radial fossa. 
 
 Trochlcar Surface (1), articulates with the greater 
 sigmoid cavity (incisura semilunaris) of the ulna; is a 
 deep depression between two borders and extends 
 from the anterior to the posterior surface of the bone. 
 
 Coronoid Fossa, above the front of- the trochlear sur- 
 face, receives the coronoid process of the ulna when 
 the forearm is flexed. 
 Olecranon Fossa (q), above the back part of the trochlea, receives the 
 tip of the olecranon process, when the forearm is extended. 
 
 THE FOREARM 
 
 The skeleton of the forearm is -composed of 2 bones. 
 The Ulna, or elbow-bone, is the principal bone of the forearm. It is 
 larger and longer than the radius, forming the greater portion of the 
 articulation with the humerus. It does not enter into the formation of the 
 wrist-joint, being excluded therefrom by an interarticular nbro-cartilage. 
 It presents for examination a shaft and two extremities, on which are 
 the following points: 
 
 Olecranon Process (4), at the upper extremity, forming the elbow. It 
 is curved forward, its apex being received into the olecranon .fossa of 
 the humerus when the forearm is extended. Its posterior surface 
 gives insertion to the tendon of the triceps. In its function and 
 structure it resembles the patella. 
 
THE ULNA AND RADIUS 
 
 49 
 
 Coronoid Process (5), below the olecranon projects forward forming 
 the Tuberosity (3), its apex being received into the coronoid fossa 
 of the humerus when the forearm is flexed. Its upper surface 
 is concave for articulation with the humerus, its lower surface rough 
 for the insertion of the brachialis anticus muscle. Its inner surface 
 has a margin for the internal lateral ligament, a tubercle for the flexor 
 sublimis digitoium, and a ridge for the pronator radii teres. 
 
 Greater Sigmoid Cavity, or Incisura Semilunaris (2), lies between the 
 processes, and is divided by a vertical ridge into two unequal parts. 
 It articulates with the _trochlear surface of the 
 humerus. * IG - 29 ' 
 
 Lesser Sigmoid Cavity or Incisura Radialis (3), lies 
 external to the coronoid process; is oval and con- 
 cave, articulating with the head of the radius, and 
 giving attachment to the orbicular ligament. 
 
 Shaft (i), large and prismatic above, smaller and 
 rounded below, has the Nutrient Foramen (6) on its 
 anterior surface (i), and a prominent margin ex- 
 ternally, to which is attached the interosseous 
 membrane (7). It gives attachment to 9 of the 12 
 muscles of the forearm. 
 
 Head (8), at the carpal end, articulates with the 
 lesser sigmoid cavity of the radius, and the fibro- 
 cartilage of the wrist-joint. 
 
 Styloid Processes (9), projecting from the head in- 
 ternally and posteriorly, its apex gives attachment 
 to the ulno carpal ligament and a depression at its 
 root to the fibro-cartilage of the joint. 
 
 Groove, for the tendon of the extensor carpi ulnaris 
 
 The Radius lies externally to the ulna when the fore- 
 arm is in supination; it is prismatic in form with the base below where it 
 articulates with the carpus. The bone is curved outward and is shorter 
 than the ulna, by the length of the olecranon. It presents the follow- 
 ing points from above downward, viz. 
 
 Head (n), cylindrical and cup-shaped, articulating with the capitellum 
 of the humerus, and the lesser sigmoid cavity or radial notch, of the 
 ulna, and playing within the orbicular ligament. 
 
 Neck (12), the constricted part below the head. 
 
 Bicipital or Radial Tuberosity (13), rough behind lor the inser- 
 
O HUMAN ANATOMY 
 
 tion of the biceps, and smooth in front where it is covered by a 
 
 bursa. 
 Shaft (10), prismoid in form, presents a sharp border internally for the 
 
 attachment of the interosseous membrane; the Nutrient Foramen is on 
 
 its anterior surface. It gives attachment to 8 of the 1 2 muscles of the 
 
 forearm. 
 
 Ridge (14), for the insertion of the pronator radii teres muscle. 
 Ulnar Notch or Sigmoid Cavity, at the ulnar side of the carpal end (15), 
 
 is shallow, and articulates with the head of the ulna. 
 Articular Surface, is divided by a ridge into 2 facets for articulation 
 
 with the semilunar and scaphoid bones of the carpus. 
 Styloid Process (16), gives attachment by its apex to the radio-carpal 
 
 ligament, and by its base to the supinator longus muscle. 
 Grooves, on the posterior surface of the lower extremity, for the 
 
 tendons of the 8 extensor muscles of the thumb, and those of the radial 
 
 side of the wrist, and fingers. 
 
 THE HAND 
 
 The Bones of the Hand are divided into the carpus 8, the metacarpus 5, 
 and the phalanges 14. Total, 27 bones. 
 
 FIG. 30. 
 
 Bones of the Carpus. The 8 bones are. 
 placed in 2 rows, one row in front of the 
 other, with 4 bones in each row, as follows, 
 the right hand being in supination, nam- 
 ing from without inward, viz. 
 
 i5/ or Proximal Row, Scaphoid, or 
 Navicular (s), Semilunar, or Os 
 Lunatum (L), Cuneiform, or Os Tri- 
 quetrum (c), Pisiform (p). 
 2d, or Distal Row, Trapezium, or 
 Greater Multangular (T), Trapezoid or 
 Lesser Multangular (T), Os magnum, 
 or Os Capitatum (M), Unciform, or 
 Os Hamatum (u). 
 
 Articulations in the Carpus are 34, as follows: the number after each 
 bone representing the number of its articulations, viz. 
 
 Scaphoid; 5. Semilunar, 5. Cuneiform 3. Pisiform, i. 
 
 Trapezium, 4. Trapezoid, 4. Os-magnum, 7. Unciform, 5. 
 
CARPAL AND METACARPAL BONES 5! 
 
 Peculiarities of the Carpal Bones. The first three enter into the forma- 
 tion of the wrist-joint; the pisiform does not, but is wholly without it, and 
 may be considered a mere appendage of the carpus. When the hand is in 
 pronation 
 
 The Scaphoid (navicular), or boat-shaped bone (S) has a tuberosity 
 on, its outer side, its largest facet is uppermost and articulates with 
 the lower end of the radius (R). A transverse groove crosses its 
 posterior surface and serves for the attachment of ligaments. 
 
 The Semilunar Bone (os lunatum) (L) has a crescentic facet externally, 
 and a convex facet superiorly, where it articulates with the radius. 
 
 The Cuneiform Bone (os triquetrum) (C) is wedge-shaped, its convex 
 surface above, articulating with the interarticular nbro-cartilage of 
 the wrist (F). It has an oval facet anteriorly for articulation with 
 the pisiform. 
 
 The Pisiform Bone (os pisiforme) (P) is the smallest, and has but one 
 facet, which lies posteriorly when the bone is in position. 
 
 The Trapezium (os multangulum majus) (T) has a deep groove for the 
 tendon of the flexor carpi radialis, and a saddle-shaped facet, infe- 
 riorly for the base of the ist metacarpal. 
 
 The Trapezoid (os multangulum minus) (T) is small and quadrilateral, 
 bent on itself, with a saddle-shaped facet looking downward, for the 
 base of the 2d metacarpal bone. 
 
 The Os-magnum (os capitatum) (M) has a head looking upward, a 
 neck, and a body; is the largest bone of the carpus, and has 3 facets 
 on the inferior surface for articulation with the 2d, 3d, and 4th 
 metacarpal bones. 
 
 The Unciform Bone (os hamatum) (U) is wedge-shaped, with a con- 
 cavity which lies to the outer side, and the unciform process, long and 
 curved, projecting from its palmar surface. 
 
 OSSA METACARPALIA 
 
 The Metacarpus consists of the 5 metacarpal bones which are placed 
 between the carpus and the phalanges. They are long bones, and each 
 has a head, shaft and base. Their heads articulate with the respective 
 phalanges. 
 
 The Thumb or ist Metacarpal Bone (i), articulates with the trapezium, 
 (greater multangular}, is shorter than the others by one-third, and 
 its base has but i articular facet. 
 
 The Index or id Metacarpal Bone (2), articulates with 3 bones of the 
 carpus, the trapezium, (gr"ater multangular} trapezoid (lesser mult- 
 
52 HUMAN ANATOMY 
 
 angular) and os-magnum (capitate) ; its base is large, and has 4 articu- 
 lar facets. 
 
 The Middle or 3^ Metacar pal Bone (3), articulates with i bone of the 
 carpus, the os-magnum (capitate} ; its base has a projecting process on 
 the radial side, and 2 small facets on the opposite side. 
 
 The Ring or tfh Metacar pal Bone (4), articulates with 2 bones of the 
 carpus and with the adjacent metacarpal bones; its base is small and 
 has 2 circular facets i on each side. 
 
 The Little or $th Metacarpal Bone (5), articulates with i carpal bone, 
 the unciform (hamate}, its base has i lateral articular facet. 
 
 The Phalanges DigitorumManus or finger-bones, are 14 in number, 3 to 
 each finger, and 2 to the thumb. They are long bones, and each has a 
 base, a shaft, and a digital extremity. The Bases of the first row articu- 
 late with the heads of the metacarpal bones. The Digital Extremities of 
 the first and second rows have each 2 small lateral condyles, while in the 
 terminal row they are rough, for the attachment of the sensitive pulp of 
 the fingers. 
 
 THE THIGH 
 
 The Femur or thigh-bone, is the longest, largest and strongest bone in 
 the body, and is nearly cylindrical in the greater part of its extent. In 
 the vertical position of the skeleton it forms one side of a triangle, of which 
 the base is the breadth of the pelvis, and the apex at the knee-joints. 
 The base of this triangle is longest in the female, and consequently that 
 sex is usually knock-kneed. The 
 
 Head (5), articulates with the acetabulum, forms about two-fifths of 
 a sphere, and has an oval depression (6) below its centre for the attach- 
 ment of the ligamentum teres. 
 
 Neck (7), connects the head with the shaft, is pyramidal and flattened; 
 its obliquity varies with age, being less before puberty, about 120 
 to 125 degrees in the adult, and nearly horizontal to the shaft in old 
 or debilitated subjects, the cancellous bone forming the neck is 
 condensed centrally into a hard core known as the calcar femorale. 
 Great Trochanter (8), a broad, rough, quadrilateral process directed 
 outward and backward from the summit of the shaft to within three- 
 fourths of an inch of the level of the head. On its outer surface the 
 tendon of the gluteus maximus plays over a bursa. It gives insertion 
 to the obturator internus, two gemelli, pyriformis, and gluteus mini- 
 mus and medius muscles. 
 
THE FEMUR 
 
 53 
 
 Trochanteric or Digital Fossa (9), on the inner or medial surface of 
 
 the great trochanter, gives insertion to the obturator externus muscle. 
 Lesser Trochanter (10), at the inferior root of the neck posteriorly, 
 
 is small and conical, and affords insertion to the tendon of the psoas 
 
 magnus muscle, the tendon of the iliacus 
 
 being inserted immediately below it. 
 Inter-lrochanteric Line, at the base of the neck 
 
 in front runs from one trochanter to the 
 
 other, to it is attached the front part of the 
 
 capsule of the hip-joint. 
 Inter-trochanteric Ridge or Crest, at the base of 
 
 the neck behind, to its middle portion is 
 
 attached the quadratus femoris muscle. 
 Shaft, is slightly curved forward, broad and 
 
 cylindrical at each end, and narrow and 
 
 triangular in the centre. Its nutrient foramen 
 
 perforates its posterior surface below the 
 
 centre, and is directed toward the hip. From 
 
 its anterior surface arise the crureus or vastus- 
 
 intermedius, and subcrureus or articularis 
 
 genu muscles. 
 Linea Aspera (i),- a crest lying along the central 
 
 third of the shaft posteriorly; bifurcating 
 
 above (2) towards each trochanter, also below 
 
 (4) towards the 2 condyles. To its outer lip 
 
 is attached the vastus externus, or lateralis, 
 
 to its inner lip, the vastus internus, or medi- 
 an's; and between them, the pectineus, ad- 
 ductor brevis, and gluteus maximus above the 
 
 short head of the biceps below, and the 
 
 adductors longus and magnus along the 
 
 greater portion of the space. 
 Groove, crossing the internal condylar ridge, 
 
 lodges the femoral artery. 
 Popliteal Space, triangular and smooth, lying between the condylar 
 
 ridges, for the popliteal artery. 
 Lateral or External Condyle (n), broader and shorter than the internal, 
 
 so as to form a horizontal articulation, the bone being inclined towards 
 
 the median line. It gives attachment to the external lateral liga- 
 ment, the popliteus, and the lateral head of the gastrocnemius. 
 Medial or Internal Condyle (12), the longer by half an inch; it gives 
 
54 HUMAN ANATOMY 
 
 attachment to the internal lateral ligament and medial head of the 
 
 gastrocnemius muscle. 
 Intercondylar Notch (13), lodges the crucial, or cruciate, ligaments. 
 
 In front the condyles are continuous with each other, forming a 
 
 concave depression or trochlea for the patella. 
 Lateral Epicondyle or Outer Tuberosity (14), on the external condyle, 
 
 for the attachment of the external lateral ligament. 
 Groove, below the outer tuberosity, for the tendon of the popliteus 
 
 muscle, terminating in a depression whence the muscle takes its origin. 
 Medial Epicondyle or Inner Tuberosity (15), on the internal condyle, 
 
 for the attachment of the internal lateral ligament. 
 Adductor Tubercle, above the inner tuberosity, for the insertion of the 
 
 tendon of the adductor magnus muscle. 
 Depression, behind the tubercle, for the tendon of the inner head of 
 
 the gastrocnemius. 
 
 THE PATELLA 
 
 The Patella is flat and triangularly ovoidal with its apex directed 
 downward. 
 
 Subcutaneous Surface, convex, presenting longitudinal ridges and many 
 nutrient foramina. 
 
 Apex, very rough on its deep surface for attachment of ligamentum 
 patellae. Articular surface presents a longitudinal articular ridge 
 flanked by concave facets of which the lateral one is the larger. The 
 medial facet often presents a "third facet" along its medial border. 
 
 THE LEG 
 
 The skeleton of the leg consists of 3 bones, the tibia, the fibula, and the 
 patella, the latter being a large, sesamoid bone placed in front of the knee. 
 
 The Tibia, or shin-bone, ranks next to the femur in respect to size and 
 length. Its form is prismoidal, the upper extremity being much larger 
 than the lower. It presents the following points: 
 
 Head, expands into two tuberosities, internal (2) and external (3) 
 which articulate with the condyles of the femur. In spite of their 
 being receiving cavities, the tuberosities of the tibia are sometimes 
 called condyles. 
 
 Spine or Eminentia Intercondyloidea (4), projects vertically between 
 the 2 articular surfaces, is bifid, affording attachment to the semilunar 
 fibro-cartilages (semilunar menisci), and by depressions in front and 
 behind its base to the crucial ligaments of the joint. 
 
 Extensor Tuberosity (5), on the head, anteriorly between the tuber- 
 osities, for the insertion of the ligamentum patellae. 
 
THE TIBIA AND FIBULA 
 
 55 
 
 Popliteal Notch or Posterior Intercondylar Fossa, posteriorly between 
 the tuberosities, affords attachment to the posterior crucial ligament. 
 
 Groove, on the inner tuberosity (2) posteriorly, for the insertion of the 
 tendon of the semi-membranosus muscle. 
 
 Facet, on the outer tuberosity (3) posteriorly and looking downward, 
 for articulation with the head of the fibula. 
 
 Soleus Ridge or Popliteal Line, obliquely across the 
 upper part of the shaft posteriorly, affords attach- 
 ment to the soleus. 
 
 Nutrient Canal, the largest in the skeleton, opens 
 just below the popliteal line, and is directed down- 
 ward. 
 
 Shaft (i), has 3 sharp ridges, i in front, the Crest 
 (6) or Shin, and i on either side, to the external of 
 which is attached the interosseous membrane. 
 
 Lower Extremity (7), is smaller than the upper, 
 grooved posteriorly for the tendon of the flexor 
 longus pollicis; externally has a rough triangular 
 depression for articulation with the fibula, and for 
 the attachment of the inferior interosseous liga- 
 ment. Its inferior surface is concave and smooth 
 for articulation with the upper surface of the astrag- 
 alus or talus. 
 
 Internal Malleolus (8), projects downward from the 
 internal side of the lower extremity. It articulates 
 with the astragalus (talus) , is grooved posteriorly for 
 the tendons of the tibialis posticus and flexor longus 
 digitorum muscles, and affords attachment to the 
 internal lateral ligament. 
 
 The Fibula, is a long slender bone, placed nearly parallel 
 with the tibia on the outer side of the leg. It is also called the Peroneus, 
 or peroneal bone. 
 
 Head (10), articulates with the external tuberosity (lateral condyle) 
 of the tibia by a flat facet. Externally, it has a prominence for the 
 attachment of the long external lateral ligament of the knee-joint. 
 
 Styloid Process, or Apex Capituli, projects upward from the head 
 posteriorly, and gives insertion to the tendon of the biceps muscle, 
 and the short external lateral ligament of the knee-joint. 
 
 Shaft (9), is twisted about ninety degrees on its long axis. It is 
 ften very irregular and may present numerous longitudinal ridges 
 
56 HUMAN ANATOMY 
 
 which seem to give it many surfaces. However, it always presents 
 certain characteristics which are constant. On the outer or lateral 
 surface at its distal end, it presents a long smooth subcutaneous 
 triangle. The ridge running from the apex of this triangle to the 
 front of the head of the bone, is the anterior border or crest. The 
 very first ridge internal (medial) to anterior border, no matter how 
 near or distant it may be, is the interosseous border or crest. This 
 border runs upward from the rough interosseous triangle to the 
 inner (medial) side of the head. It may, for part of its length, join 
 the anterior border. Running spirally upward from the groove for 
 the peroneal tendons to the styloid process (apex capituli), is the 
 posterior border (lateral crest}. The interval between the anterior 
 border and the interosseous border, however narrow it may be, is the 
 extensor surface (anterior part of the medial surface), from above 
 downward it gives attachment to extensor digitorum communis, 
 extensor hallucis longus, and peroneus tertius. The interval be- 
 tween the anterior border and the posterior border (lateral crest) is 
 the peroneal surface (lateral surface). The upper third of this 
 surface gives attachment to the peroneus longus, the middle third, 
 to the peroneus brevis; lower third is free. The entire interval be- 
 tween the posterior border and the interosseous border is the flexor 
 surface. Running from the back of the head downward and forward 
 and finally joining the interosseous border, is the oblique ridge 
 (not border) also called the medial crest. This oblique ridge 
 divides the flexor surface into two portions; one which is close to 
 the interosseous border (posterior portion of the medial surface) for 
 the tibialis posticus; the remainder of the flexor surface which is 
 distant from the interosseous ridge (posterior surface), from above 
 downward gives attachment to the soleus and flexor hallucis longus. 
 
 Nutrient Canal, opens about the centre of the shaft posteriorly, its 
 canal running downwards. 
 
 External Malleolus (n), is the lower extremity of the bone. It is 
 larger and longer than the internal, articulates with the astragalus by 
 a triangular facet, and is grooved posteriorly for the tendons of the 
 peroneus longus and peroneus brevis muscles. Its edge affords attach- 
 ment to the external lateral ligaments of the ankle-joint. 
 
 THE FOOT 
 
 The Bones of the Foot are divided into those of the tarsus 7, metatarsus 
 5, and phalanges 14. Total, 26 bones. 
 
THE BONES OF THE FOOT 
 
 FIG. 33. 
 
 Bones of the Tarsus are placed in 2 rows side by side, 2 bones in the 
 external row, 5 in the internal, as follows, viz. 
 
 Internally, Astragalus or Talus (5). Scaphoid or Navicular (8). 3 
 Cuneiform (10, n, 12). 
 
 Externally, Os calcis (i), or Calcaneum. Cuboid (6). 
 
 (The illustration, Fig. 33, shows the plantar 
 surface of the skeleton of the foot.) 
 
 Articulations in the Tarsus are 28 in num- 
 ber, each bone articulating with 4 others, 
 except the os calcis (calcaneus), which articu- 
 lates with 2, and the external (third) cunei- 
 form with 6 bones. 
 
 Peculiarities of the Tarsal Bones. They 
 may be divided transversely at the astrag- 
 al o-scaphoid-calcaneo-cuboid articulation , 
 the site of Chopart's operation. The 
 
 Astragalus or Talus (5), has a rounded 
 head, a convex surface on which is a 
 broad articular facet, and on its inferior 
 surface a deep groove between 2 articu- 
 lar facets. 
 
 Os Calcis or Calcaneus (i), is a large bone, 
 having on its upper surface a deep groove 
 for the interosseous ligament, between 
 2 articular surfaces; anteriorly a large 
 irregular portion, the head; and poste- 
 riorly an elongated portion forming the 
 Heel (2). On its internal surface is a 
 
 projection, the Sustentaculum Tali, which supports the internal 
 articulating surface; below which process the bone is deeply grooved 
 for the plantar vessels and nerves and the flexor tendons. To the os 
 calcis are attached 8 muscles and the plantar fascia. 
 
 Navicular or Scaphoid Bone (8), is boat-shaped, has 3 facets anteriorly 
 for the cuneiform bones, a concave surface posteriorly for the astrag- 
 alus, and a facet externally for the cuboid bone. A tubercle (9) is 
 situated on the lower surface internally, for the insertion of the tibialis 
 posticus muscle. 
 
 Cuboid Bone (6), has 3 articular surfaces, and a groove inferiorly for 
 the tendon of the peroneus longus. 
 
 Internal or First Cuneiform Bone (10), the largest of the 3, has a tubercle 
 
 EJAL.9, 
 
58 HUMAN ANATOMY 
 
 on its plantar surface for the insertion of parts of the tendons of the 
 
 tibialis anticus and tibialis posticus muscles. 
 Middle or Second Cuneiform Bone (n), is small and wedge-shaped with 
 
 the narrow end downward. Its anterior surface is considerably 
 
 behind the line of the tarso-metatarsal articulation, thus forming a 
 
 recess into which the base of the second metatarsal bone fits. 
 External or Third Cuneiform Bone (12), is also wedge-shaped, but 
 
 longer than the middle one; and affords origin to i muscle, the flexor 
 
 brevis pollicis. 
 
 The Metatarsus consists of 5 metatarsal bones, which are long bones, 
 
 having each a shaft and two extremities. Their bases articulate with the 
 
 tarsal bones and with each other; their heads with the first row of phalanges. 
 
 ist Metatarsal (i3), : is large but shorter than^the others, and forms the 
 
 inner border of the foot, articulating with the internal cuneiform. 
 
 The head is large and has two grooved facets on its plantar surface, 
 
 over which glide 2 sesamoid bones (19). 
 2d Metatarsal (14), is the longest; its base has 3 facets for articulation 
 
 with the 3 cuneiform bones in the recess formed by the shortness of 
 
 the middle or second cuneiform. 
 $d Metatarsal (15), has 2 facets on the inner side of its base, besides 
 
 the facets for the internal cuneiform and the 4th metatarsal bone. 
 4th Metatarsal (16), articulates with the cuboid bone, and also with the 
 
 internal or first cuneiform. 
 ^th Metatarsal (17), articulates obliquely with the cuboid bone, and 
 
 has a tubercular projection (18) on the outer surface of its base, which 
 
 forms the guide in Key's operation. 
 
 The Phalanges of the Foot number 14 as in the hand, the great toe 
 having two (20, 21), the other toes three each. They are long bones, 
 each having a base, a shaft, and an anterior extremity. They are convex 
 above, concave below, and articulate by the bases of the first row with the 
 bones of the metatarsus. The anterior extremities of the distal phalanges 
 (21, 23) are expanded into surfaces for the support of the nails and pulp 
 of the toes. 
 
 THE ARTICULATIONS 
 
 An Articulation or Joint is a connection between two bones of the skele- 
 ton, and has entering into its formation the following-named structures 
 bone, cartilage, fibro-cartilage, ligament and synovial membrane. 
 
ARTICULATIONS 
 
 Articulations are divided into three classes, Synarthrosu, immovable 
 joint; Amphiarthrosis, mixed articulation, having limited motion; and 
 Diarthrosis, movable joint, having free motion. 
 
 Synarthroses are subdivided into Sutura, formed by processes and in- 
 dentations; Schindy'lesis, by a plate of bone entering into a fissure of an- 
 other; and Gompho'sis, by a conical process into a socket. The Sutura are 
 again subdivided into S. dentata, having tooth-like processes; S. serrata, 
 with serrated edges; S. limbosa, having beveled margins and dentated proc- 
 esses; S. squamosa, with thin beveled margins overlapping each other; S. 
 harmonia, contiguous rough surfaces opposed to each other. The first 3 
 are also named Sutura Vera (true sutures) having indented borders; the 
 last 2 Sutura Notha (false sutures) being formed by rough surfaces. 
 
 Amphiarthroses are subdivided into Symphysis, connected by fibro- 
 cartilage and not separated by synovial membrane; Syndesmosis, united 
 by an interosseous ligament. 
 
 Diarthroses are subdivided into Ginglymus, hinge-joint; Trochoides, 
 pivot-joint, formed by a ring surrounding a pivot; Condyloid, by an ovoid 
 head in an elliptical cavity; Reciprocal Reception, saddle-joint, by surfaces 
 inversely convex and concave; Enarthrosis, ball-and-socket joint; Arthrodia, 
 gliding joint. 
 
 Examples of each of the above-named articulations, as follows: 
 Synarthrosis, joints of the cranium and face, except the lower jaw. 
 
 Sutura Dentata, the inter-parietal suture. 
 
 Sutura Serrata, the inter-frontal suture. 
 
 Sutura Limbosa, the fronto-parietal suture. 
 
 Sutura Squamosa, the temporo-parietal suture. 
 
 Sutura Harmonia, the intermaxillary suture. 
 
 Schindylesis, rostrum of sphenoid with the vomer. 
 
 Gomphosis, the teeth in their alveoli. 
 Amphiarthrosis, the joints between the bodies of the vertebras (sym- 
 
 physes), the inferior tibio-fibular articulation (syndesmosis). 
 Diarthrosis, movable joint, as follows: 
 -Ginglymus, inter-pharyngeal joints and the elbow-joint. 
 Trochoides, superior radio-ulnar, atlanto-axial joint. (Articulatio 
 Atlanto-epistrophica.) 
 
 Condyloid, the wrist-joint. 
 
 Reciprocal Reception, the carpo-metacarpal joint of the thumb. 
 
 Enarthrosis, the hip- and shoulder-joints. 
 
 Arthrodia, the carpal and tarsal articulations. 
 
OO HUMAN ANATOMY 
 
 Varieties of Motion in Joints are 4 in number, viz. gliding, angular 
 movement (including adduction, abduction, flexion and extension), 
 circumduction and rotation. These movements are often more or less 
 combined in the various joints. 
 
 Structures entering into the formation of Joints are 5, viz., the 
 articular lamella of bone, cartilage, fibro-cartilage, ligaments and synovial 
 membrane. 
 
 Articular Lamella of Bone differs from ordinary bone tissue in being 
 more dense, containing no Haversian canals nor canaliculi, and having 
 larger lacunae. 
 
 Cartilage, a non-vascular structure, is divisible into temporary and 
 permanent varieties. The first forms the original frame-work of the 
 skeleton, and becomes ossified. Permanent cartilage is not prone 
 to ossification, and is divided into 4 groups, Articular, covering the 
 ends of bones in joints; Inter articular, between the bones in a joint; 
 Costal, forming part of the skeleton; and Membraniform. According 
 to its minute structure, cartilage is divided into Hyaline Cartilage, 
 White Fibro-cartilage and Yellow or Elastic Fibro-cartilage. 
 
 Fibro-cartilages, in joints and osseous grooves are of the white variety 
 and may be arranged in 4 groups, the Inter articular (menisci) , separat- 
 ing the bones of a joint; Connecting, binding bones together; Circum- 
 ferential, deepening cavities; Stratiform, lining grooves. 
 
 Ligaments are bands of white fibrous tissue, except the ligamenta 
 subflava and the ligamentum nuchse, which consist entirely of yellow 
 elastic tissue. 
 
 Synovial Membranes secrete the synovia, a viscid, glairy fluid, and 
 resemble the serous membranes in structure. They are Articular, 
 lubricating joints; Bursal, forming closed sacs (bursae), interposed 
 between surfaces which move upon each other; Vaginal, ensheathing 
 tendons. 
 
 ARTICULATIONS OF THE TRUNK 
 
 The Temporo-mandibular Articulation is a ginglymo-arthrodial joint 
 between the condyle of the lower jaw and the anterior part of the glenoid 
 cavity of the temporal bone. It has 2 synovial membranes with an 
 interarticular fibro-cartilage between them, and 4 ligaments, viz. 
 
 External Lateral, from the tubercle of the zygoma to the outer side of 
 the neck of the condyle of the lower jaw. 
 
 Spheno-mandibular or Internal Lateral (d), from the alar spine of the 
 
ARTICULATIONS OF THE TRUNK 
 
 6l 
 
 PIG. 34- 
 
 sphenoid to the mandibular spine or lingula on the margin of the 
 dental foramen. 
 Stylo-mandibular (/), from the styloid process of the temporal bone tc 
 
 the angle and posterior border of the ramus of the lower jaw. 
 Capsular (c), from the edge of the glenoid cavity and the eminentia 
 
 articularis to the neck of the condyle of the lower jaw. 
 Its Nerves are derived from the auriculo- 
 temporal and masseteric branches of the 
 mandibular. Arteries from the temporal 
 branch of the external carotid. 
 The Vertebral Articulations are formed by 
 the adjacent surfaces of the bodies of the 
 vertebrae and their processes, and are con- 
 nected by the following ligaments, etc. 
 ' Anterior Common Ligament (i), along the 
 
 fronts of the bodies. 
 f\\ Posterior Common Ligament, along the 
 
 backs of the bodies. 
 
 2J Ligamenta Subflava, connect the laminae of adjacent vertebrae. 
 If I Capsular (4), surround the articular processes and are lined by 
 synovial membrane. 
 
 ^j 
 
 Supra-spinous and nter-spinous, 
 
 FIG. 35. 
 
 connect the spinous processes. 
 
 In the cervical region they form 
 
 what is called the Ligamentum 
 
 Nuchae. 
 Inter-transverse (3), connect the 
 
 transverse processes. 
 Intervertebral Substance, in lentic- 
 
 ular disks between the bodies of 
 
 the vertebrae, from the axis to 
 
 the sacrum. 
 
 The Atlanto-axial Articulation is 
 a double arthrodia or gliding joint 
 between the articular processes and 
 
 a pivot articulation between the atlas and the odontoid process. It 
 has 6 ligaments and 4 synovial membranes, as follows: 
 Anterior 2, and Posterior i, Atlanto-axial, -continuations of the anterior 
 
 and posterior common spinal ligaments. 
 
 Capsular 2, surrounding the articular surfaces, each lined by a synoviai 
 membrane. 
 
62 
 
 HUMAN ANATOMY 
 
 PIG. 36. 
 
 Transverse Ligament, divides the spinal foramen of the atlas into two 
 portions, stretching across between the tubercles on the inner sides of 
 the articular processes. It holds the odontoid process in place, having 
 a synovial membrane interposed. Another synovial membrane is 
 situated between the process and the anterior arch. The transverse 
 ligament sends two vertical slips, one upward, the other downward, 
 from which it is often named the Cruciform Ligament. 
 
 The Occipito-atlantal Articulation is a double condyloid formed by the 
 
 condyles of the occipital bone with the 
 superior articular surfaces of the atlas, 
 and has 6 ligaments, viz. 
 
 Anterior Occipito-atlantal (a), from 
 the anterior margin of the fora- 
 men magnum to the anterior arch 
 of the atlas. 
 
 Posterior Occipito-atlantal, from the 
 posterior margin of the foramen 
 magnum to the posterior arch of 
 the atlas. It is perforated by the 
 vertebral and suboccipital nerves. 
 Lateral 2, from the jugular processes of the occipital bone to the bases 
 
 of the transverse processes of the atlas. 
 
 Capsular 2 (d), around the articular surfaces, lined by synovial mem- 
 brane. 
 
 The Occipito-axial Articulation is formed by the occipital bone and the 
 odontoid process of the axis, which do not articulate with each other 
 strictly, but are connected with 4 ligaments, the 
 
 Occipito-axial (i) (Membrana Tectoria), a continuation of the posterior 
 
 common spinal ligament to the basilar process of the occipital bone. 
 
 Lateral Occipito-odontoid (5) (Check Ligaments} 2, from the head of 
 
 the odontoid process to the inner sides of the occipital condyles. 
 Middle Odontoid (Ligamentum Suspensorium), from the anterior mar- 
 gin of the foramen magnum to the odontoid apex. 
 The Costo-vertebral Articulations are each a double arthrodia between 
 the head of the rib and the bodies of 2 adjacent vertebrae, except in the 
 ist, roth, nth, and i2th ribs, which are single, as they articulate with 
 but i vertebra each. Their ligaments are 3, viz. 
 
 Anterior Costo-central (2), or Stellate Ligament, consists of 3 bundles, 
 which fasten the anterior part of the head of the rib to the inter- 
 vertebral disk and the 2 adjacent bodies. 
 
ARTICULATIONS OF THE TRUNK 63 
 
 Intra-articiilar, in the interior of the joint, from the crest on the head 
 of the rib to the intervertebral disk; on each side there is a separate 
 synovial membrane. In the ist, loth, nth and i2th ribs it does not 
 exist, hence there is but one synovial membrane. 
 
 Capsular, surrounding the articular surfaces. 
 
 The Costo-transverse Articulations are 10 arthrodial articulations 
 between the tubercles of the first 10 ribs and the transverse processes of the 
 vertebrae next below. Their ligaments are 4, viz. Anterior superior, 
 Middle (interosseous), Posterior Costo-transverse and Capsular. 
 
 The Chondro-sternal Articulations are 7 in number, i of which (the 
 first) is a synarthrodial and 6 are arthrodial articulations, between the 
 costal cartilages and the margin of the sternum. The first has no synovial 
 membrane, the second only has an intra-articular ligament. Each has 4 
 ligaments, the Anterior and Posterior Chondro-sternal, a Capsular, and an 
 Inter articular. The Chondro-xiphoid Ligaments connect the xiphoid ap- 
 pendix to the cartilage of the 6th or 7th rib. 
 
 The Costo-chondral and Interchondral Articulations connect the 
 
 costal cartilages with the ribs and with each other respectively. With 
 the ribs by a depression on the end of each rib, strengthened by the 
 blending together of the periosteum and the perichondrium. The 6th, 
 7th and 8th, and sometimes the pth and loth costal cartilages articulate 
 with each other by their borders and each has a Capsular and an Inter- 
 chondral ligament, with 3 synovial membranes for the 3 articulations 
 between the 6th and the pth cartilages. 
 
 The Ligaments of the Sternum are an Anterior Sternal and a Posterior 
 Sternal ligament, with a layer of cartilage between the manubrium and the 
 gladiolus. 
 
 The Sacro-vertebral Articulation is similar to the other vertebral 
 articulations, but has 2 additional ligaments on each side, the 
 Lumbo-sacral, from the transverse process of the 5th lumbar vertebra 
 
 .to the base of the sacrum laterally and anteriorly. 
 Ilio-lumbar, from the apex of the transverse processes of the 5th 
 
 lumbar vertebra to the crest of the ilium in front of the sacro-iliac 
 
 articulation. 
 
 The Sacro-coccygeal Articulation is an amphiarthrodial joint, and has 
 4 ligaments, viz. 
 
 Anterior Sacro-coccygeal. 
 Posterior Sacro-coccygeal. 
 
6 4 
 
 HUMAN ANATOMY 
 
 Two Lateral Sacro-coccygeal. 
 Fibro-cartilage, interposed in the joint. 
 
 The Sacro-iliac Articulation is an amphiarthrodial joint, formed by the 
 lateral surfaces of the sacrum and ilium. Its ligaments on each side are 
 the 
 
 Anterior Sacro-iliac. 
 
 Posterior Sacro-iliac (8), which consists of a short transverse part 
 (8) and a long part known as the 
 Oblique Sacro-iliac. 
 
 The Sacro-ischiatic Articulation is 
 an amphiarthrosis between the sa- 
 crum and the ischium. Its liga- 
 ments convert the sacro-sciatic 
 notches into foramina, the greater 
 notch (5) being crossed by the lesser 
 ligament, the lesser notch (6) by the 
 greater ligament. These foramina 
 are described on page 13 ante. 
 
 Posterior or Great Sacro-sciatic 
 Ligament (1. sacrotuberosum) 
 (13), is the divorced tendon of 
 the biceps femoris muscle, it ex- 
 tends from the posterior inferior 
 spine of the ilium and the pos- 
 terior surface and margins of 
 the sacrum and coccyx (2), to 
 the inner margin of the tuber- 
 
 csity (4) and the ascending ramus (14) of the ischium, the latter por- 
 tion being known as the Falciform Ligament. 
 
 Anterior or Lesser Sacro-sciatic Ligament (1. sacrospinosum) (15), from 
 the margins of the sacrum and coccyx, into the spine of the ischium 
 (16). 
 
 The Pubic Articulation or Symphysis Pubis, is an amphiarthrodial 
 joint formed by the junction of the two pubic bones with each other. 
 It has an interpubic disk and 4 ligaments, the 
 
 Anterior Pubic. Posterior Pubic. Superior Pubic 
 
 Sub-pubic, forming a fibrous arch between the rami. 
 
 ARTICULATIONS OF THE UPPER EXTREMITY 
 The Sterno -clavicular Articulation is an arthrodial joint, formed by 
 the sternal end of the clavicle with the sternum and the cartilage of the ist 
 
ARTICULATIONS OF UPPER EXTREMITY 
 
 the 
 
 FIG. 38. 
 
 rib. It has an interarticular fibro-cartilage, 2 synovial membranes and 5 
 ligaments, the 
 
 Anterior Sterno-clavicidar. Inter clavicular. 
 
 Posterior Ster no-clavicular. Costo-clavicular or Rhomboid. 
 
 Capsular, Formed by the anterior and posterior. 
 
 The Acromio-clavicular Articulation is an arthrodial joint, formed by 
 the outer extremity of the clavicle and the acromion process of the scapula. 
 It frequently has an interarticular fibro-cartilage and 2 synovial mem- 
 branes (usually but i is present). It has 3 ligaments, the 
 Superior Acromio-clavicular(i}. Coraco-clavicular(2) j Trapezoid, externally. 
 Inferior Acromio-clavicular. divided into I. Conoid, internally. 
 
 Proper Ligaments of the Scapula are 2, the Coraco-acromial, and the 
 Transverse, as follows: 
 
 Coraco-acromial (3), completes the vault partially formed by 
 coracoid and acromion processes over the head of the humerus. 
 Transverse (4), from the base of the 
 coracoid process to the margin of the 
 suprascapular notch, converting it into 
 a foramen for the suprascapular nerve. 
 The Shoulder- joint, Articulatio Humeri, 
 is an enarthrodial or ball-and-socket joint, 
 formed by the head of the humerus and the 
 glenoid cavity of the scapula. It has a 
 Synovial Membrane which is reflected upon 
 the tendons of the biceps, subscapularis, 
 and infraspinatus muscles, and communi- 
 cates with bursae beneath the 2 latter ten- 
 dons. Its Arteries are derived from the 
 anterior and posterior circumflex and the 
 suprascapular; its Nerves from the circum- 
 flex (n. axillaris) and the suprascapular. 
 It has 3 ligaments, the 
 
 Capsular (5), from the margin of the 
 
 glenoid cavity to the anatomical neck of the humerus; has 3 open- 
 ings for the reflexions of the synovial membrane over the tendons. 
 Coraco-humeral (6), intimately united with the capsular, extends from 
 
 the coracoid process to the greater tuberosity of the humerus. 
 Glenoid, a fibre-cartilaginous ring, continuous above with the tendon of 
 the long head of the biceps (7), and attached around the margin of 
 
66 
 
 HUMAN ANATOMY 
 
 FIG. 39 
 
 the glenoid cavity in order to deepen the articular surface and pad 
 its edge. 
 
 The Elbow-joint, Articulatio Cubiti, is a ginglymus or hinge articulation, 
 formed by the lower end of the humerus with the greater sigmoid cavity 
 of the ulna (2) and the head of the radius (3). Its Synovial Membrane 
 is reflected over the ligaments, and includes the superior radio-ulnar 
 articulation. Its Arteries are derived from the anastomotica magna, 
 brachial, radial, ulnar, and interosseous recurrent, superior and inferior 
 profunda arteries. Its Nerves are branches of the ulnar, the musculo- 
 cutaneous and the median. It has 4 ligaments, the 
 
 Anterior, from the internal condyle (7) and anterior 
 surface of the humerus to the orbicular ligament 
 of the radius and the coronoid process of the ulna. 
 Posterior (6), from the posterior surface of the 
 
 humerus to the olecranon process of the ulna. 
 External Lateral (1. collaterale radiale) (4), from the 
 external condyle of the humerus passing obliquely 
 downward and backward behind the orbicular 
 ligament and the head of the radius to be attached 
 strongly to the ulna at a point opposite the attach- 
 ment of the internal lateral ligament. 
 Internal Lateral (1. collaterale ulnare), from the in- 
 ternal condyle of the humerus (7) to the inner side 
 of the juncture of the coronoid and olecranon proc- 
 ,ess^of the ulna. 
 
 The Radio-ulnar Articulations are 3 in number, as 
 follows: 
 
 SUPERIOR RADIO-ULNAR ARTICULATION is a trochoid 
 or pivot-joint, formed by the head of the radius and the 
 lesser sigmoid cavity of the ulna. Its synovial mem- 
 brane is a continuation of that in the elbow-joint. It 
 has only one ligament, the 
 Orbicular Ligament (5), consists of two distinct portions, the orbicular 
 and the capsular. The orbicular portion is very thick, forms 
 four-fifths of a circle and surrounds the neck of the radius. It is 
 attached to the margins of the lesser sigmoid cavity of the ulna, and 
 to the external lateral ligament of the elbow-joint. The Capsular 
 portion is loose and thin, its fibres run from the lower margin of the 
 true orbicular ligament to the neck of the radius. 
 MIDDLE RADIO-ULNAR ARTICULATION is formed by the shafts of the 
 
ARTICULATIONS OF UPPER EXTREMITY 67 
 
 radius and ulna, which do not touch each other, but are connected by 2 
 ligaments, as follows: 
 
 Oblique Ligament, from the tubercle at the base of the coronoid process 
 of the ulna to the shaft of the radius. Its fibres run from the ulna 
 obliquely downward to the radius, whereas the fibers of the inter- 
 osseous membrane run from the radius downwards to the ulna. 
 Interosseous Membrane (9), -obliquely downward from the interosseous 
 ridge on the radius to that on the ulna. Through the interval between 
 its upper border and the oblique ligament, the posterior interosseous 
 vessels pass. 
 
 INFERIOR RADIO-ULNAR ARTICULATION is a pivot-joint, formed by the 
 head of the ulna and the sigmoid cavity of the radius. Its Synovial 
 Membrane (membrana sacciformis) is very loose, and sometimes com- 
 municates with that of the wrist-joint through an opening in the triangular 
 fibro-cartilage which separates the head of the ulna from the wrist-joint. 
 It is a capsule but is often considered as consisting of two portions which 
 are then called, 
 
 Anterior Radio-ulnar. Posterior Radio-ulnar. 
 
 ++- 
 
 The Radio-carpal Articulation, or Wrist-joint, is a condyloid articula- 
 tion formed by the lower end of the radius and the triangular fibro-cartilage 
 with the scaphoid (os naviculare), semilunar (os lunatum), and cuneiform, 
 (os triquetrum) bones of the carpus. Its Arteries are the anterior and pos- 
 terior carpal from both the radial and ulnar, the anterior and posterior 
 interosseous and ascending branches from the deep palmar arch. Its 
 Nerves are derived from the ulnar and posterior interosseous. It is lined 
 by a synovial membrane, and is connected by a capsule, which is divided 
 into the following-named 4 ligaments, the 
 
 External Lateral (radio-carpal). Anterior Ligament. 
 
 Internal Lateral (ulno-carpal). Posterior Ligament. 
 
 The Carpal Articulations are in 3 sets, between the bones of the 
 first row, between the bones of the second row, between the 2 rows of 
 bones with each other. 
 
 The scaphoid, semilunar, and cuneiform bones are connected together 
 by Dorsal, Palmar (volar), and 2 Inter osseous Ligaments. The pisiform 
 bone has a separate capsular ligament and synovial membrane and 2 
 Palmar Ligaments connecting it with the unciform and the 5th 
 metacarpal. 
 
 The 4 bones of the second row are connected together by Dorsal, 
 Palmar and 3 Interosseous Ligaments. 
 
68 HUMAN ANATOMY 
 
 The two rows of bones are united to each other by Dorsal, Palmar, and 
 2 Lateral Ligaments, the last named being continuous with the 
 lateral ligaments of the wrist-joint. 
 
 The Carpo-metacarpal Articulations. That of the thumb with the 
 trapezium is a joint of reciprocal reception, and has a Capsular Ligament 
 and a separate synovial membrane. The 4 inner metacarpal bones form 4 
 arthrodial joints with the adjacent carpal bones by 6 Dorsal, 8 Palmar, and 
 2 Interosseous Ligaments, irregularly disposed. 
 
 The Synovial Membranes of the Wrist are 5 in number, and are situated 
 as follows: 
 
 The First, or Membrana Sacciformis, between the head of the ulna, 
 the sigmoid cavity of the radius, and the triangular interarticular 
 fibro-cartilage. 
 
 The Second, between the lower end of the radius, the triangular fibro- 
 cartilage, and the scaphoid, semilunar, and cuneiform bones of the 
 carpus. 
 
 The Third, between all the carpal bones except the pisiform and 
 
 between the bases of the inner 4 metacarpal bones; but it extends 
 
 only halfway into the 2 intervals between the 3 proximal bones of the 
 
 carpus. 
 
 The Fourth, between the trapezium and the metacarpal bone of the 
 
 thumb. 
 
 The Fifth, between the cuneiform and pisiform bones. 
 The Metacarpo-metacarpal Articulations. The 4 inner metacarpal 
 bones are connected together at their bases by Dorsal, Palmar, and Inter, 
 osseous Ligaments, and at their digital extremities by the Transverse 
 Ligament, a narrow fibrous band which crosses them anteriorly. 
 
 Remaining Articulations of the Hand. The metacarpo-phalangeal 
 are condyloid joints formed by the rounded heads of the metacarpal bones 
 and the shallow cavities in the extremities of the first phalanges. The 
 phalangeal articulations are ginglymus joints. Both sets have for each 
 joint an Anterior and 2 Lateral Ligaments, the former being lined each with 
 a synovial membrane. There are no posterior ligaments to these articula- 
 tions, the extensor tendons of the hand supplying their places. 
 
 ARTICULATIONS OF THE LOWER EXTREMITY 
 
 The Hip-joint is a true enarthrodial or ball-and-socket articulation, 
 formed by the head of the femur with the acetabulum of the os innom- 
 inatum. Its Synovial Membrane is extensive, investing most of the 
 
ARTICULATIONS OF LOWER EXTREMITY 69 
 
 head and neck of the femur, the capsular, cotyloid and teres ligaments, and 
 the cavity of the acetabulum. Its Arteries are derived from the obturator, 
 sciatic, internal circumflex, and gluteal. Its Nerves are branches from the 
 sacral plexus, great sciatic, obturator, and accessory obturator. It has 5 
 ligaments as follows: the 
 
 Capsular, from the margin of the acetabulum and the transverse liga- 
 ment into the base of the neck of the femur above, the anterior inter- 
 trochanteric line in front, and to the middle of the neck of the bone, 
 behind. Superadded to and strengthening it are 3 auxiliary bands, 
 the fibres of which form part of the capsule, the ilio-femoral (de- 
 scribed below), the ischio-femoral and the pectineo- femoral bands. 
 Ilio-femoral or Y -ligament, from the anterior inferior spine of the ilium, 
 into the anterior inter-trochanteric line by two fasciculi. It is a 
 dissected portion of the capsular ligament which is very strong 
 anteriorly. 
 
 Ligamentum Teres, from a depression on the head of the femur into the 
 margins of the cotyloid notch of the acetabulum and into the trans- 
 verse ligament, by two fasciculi. 
 Cotyloid, a fibro-cartilaginous band surrounding the margin of the 
 
 acetabulum in order to deepen its cavity and pad its edge. 
 Transverse, that part of the cotyloid ligament which crosses over the 
 cotyloid notch converting it into a foramen. 
 
 The Knee-joint is a complicated articulation, formed by the condyles of 
 the femur with the head of the tibia and the patella in front. It consists of 
 3 articulations in one; those between the condyles of the femur and the 
 tuberositis of the tibia are condylar joints, while that between the patella 
 and the femur is partly trochlear. Its Synomal Membrane is the largest 
 in the body, being reflected for 2 or 3 inches over the anterior surface of the 
 femur, where it is supported by the subcrureus muscle; also over its con- 
 dyles, the patella, semilunar cartilages, crucial ligaments, and the head of 
 the tibia; and it is prolonged through an opening in the capsular ligament 
 beneath the tendon of the popliteus. Its Arteries are derived from the 
 anastomotica magna, the articular branches of the popliteal, the recurrent 
 branches of the anterior tibial and the external circumflex of the profunda. 
 Its Nerves are derived from the obturator, anterior crural, external and 
 internal popliteal. It has 14 ligaments, of which 6 are external and 8 
 internal, as follows: 
 
 Anterior, or Ligamentum Patella, is the central portion of the common 
 tendon of the extensor muscles of the thigh, continued from the patella 
 to the tubercle of the tibia (9, Fig. 41). 
 
HUMAN ANATOMY 
 
 Posterior, the oblique portion of which is often called Ligamentum 
 Winslowii (i), from the upper margin of the intercondyloid notch 
 of the femur to the posterior margin of the head of the tibia, being 
 p IG . 4 o. partly derived from the tendon of the semi- 
 
 membranosus muscle (2): 
 
 Internal Lateral (1. collateral tibiale) (5), from 
 the internal condyle of the femur to the inner 
 tuberosity of the tibia and the internal semi- 
 lunar cartilage. 
 
 External Lateral 2, from the external condyle 
 of the femur to the head of the fibula. 
 These ligaments are a Long (1. collaterale 
 fibulare) (6) is a divorced portion of the 
 peroneus longus muscle. The short external 
 lateral ligament (1. laterale externum breve 
 seu posticum) (7) is often wanting, when 
 present, it is behind the long external lateral 
 and separated from it by the tendon of the 
 biceps. 
 
 Capsular, is a thin but very strong membrane, which fills in the 
 intervals left between the preceding ligaments and is inseparably 
 connected with them. 
 The Internal Ligaments are as follows: 
 
 Anterior Crucial (2), from the depression in 
 front of the spine of the tibia to the inner side 
 of the outer condyle of the femur. 
 Posterior Crucial (3), from the depression behind 
 the spine of the tibia and the popliteal notch, to 
 the outer side of the inner condyle of the femur. 
 [To remember the positions and insertions of 
 these crucial ligaments, let the student cross 
 his index fingers over each knee in succession; 
 when over the right knee placing the right 
 finger in front, when over the left knee the 
 left finger in front. The positions of the fingers 
 will in each case correspond with those of the 
 respective crucial ligaments.] 
 
 Semilunar Fibro-cartilages (menisci) 2, external (7) and internal (6), 
 are situated between the articular surfaces, and attached to the 
 depressions in front and behind the spine of the tibia. The external 
 one forms nearly an entire circle and gives off posteriorly a strong 
 
 PIG. 41. 
 
ARTICULATIONS OF LOWER EXTREMITY 71 
 
 fasciculus, the ligament of Wrisberg, which is inserted into the inner 
 
 condyle of the femur. 
 Transverse (4), is a connecting slip between the semilunar fibro-carti- 
 
 lages anteriorly. 
 Coronary or Coronal (7), are short bands connecting the outer margins 
 
 of the fibro-cartilages with the margin of the head of the tibia. 
 Ligamenium Mucosum (plica synovialis patellaris) , is a triangular fold 
 
 of the synovial membrane which at the lower border of the patella is 
 
 given off to the intercondylar notch of the femur. 
 Ligamenta Alaria (plicae alares), are two fringe-like folds on the sides 
 
 of the ligamentum mucosum, and are attached to the semilunar 
 
 cartilages. 
 Bursa, in the vicinity of this joint are 1 2 in number; 3 in front, 4 on the 
 
 outer side, and 5 on the inner side. Some of these are expansions 
 
 from others, some often communicate with the joint, and some are 
 
 only occasionally present. That between the patella and the skin is 
 
 the one implicated in the affection called "house-maid's knee." 
 
 The Tibio-fibular Articulations are 3 in number, as follows, viz. 
 
 SUPERIOR TIBIO-FIBULAR ARTICULATION, in an arthrodial joint, formed 
 by the contiguous surfaces of the bones. It has a Synovial Membrane 
 which is sometimes continuous with that of the knee-joint, and 3 liga- 
 ments, the 
 
 Capsular, a membranous bag surrounding the joint and much thicker 
 in front than behind. 
 
 Anterior and Posterior Superior Tibio-fibular (10), which connect the 
 head of the fibula with the outer tuberosity of the tibia. 
 
 MIDDLE TIBIO-FIBULAR ARTICULATION. The shafts of these bones do 
 not touch each other, but are connected by an Interosseous Membrane 
 extending between their contiguous borders, and perforated, above for the 
 anterior tibial vessels, below for the anterior peroneal vessels. 
 
 INFERIOR TIBIO-FIBULAR ARTICULATION, is an amphiarthrodial joint, of 
 the subdivision syndesmosis, and is formed by the contiguous rough 
 surfaces on the lower ends of these bones. Its Synovial Membrane is 
 derived from that of the ankle-joint, and it has 4 ligaments, the 
 
 Inferior Interosseous, continuous with the interosseous membrane. 
 
 Anterior and Posterior Inferior Tibio-fibular, from the margins of the ex- 
 ternal malleous to the front and back of the tibia. 
 
 Transverse, posteriorly between the 2 malleoli. 
 
 The Ankle-joint is a ginglymus or hinge-joint articulation, formed by the 
 lower ends of the tibia and fibula and their malleoli, with the astragalus. 
 
72 HUMAN ANATOMY 
 
 Its Synovial Membrane is prolonged upward between the tibia and fibula for 
 a short distance. Its Arteries are derived from the malleolar branches of 
 the anterior tibial and peroneal arteries; and its Nerves from the anterior 
 and posterior tibial nerves. It has 4 ligaments; the 
 
 Anterior, connecting the anterior margins of the tibia and astragalus 
 
 or talus. 
 Posterior, a very thin band of transverse fibres, connecting the posterior 
 
 margins of the tibia and astragalus. 
 Internal Lateral or Deltoid Ligament (1. calcaneotibiale) , from the 
 
 internal malleolus to the 3 adjacent tarsal bones. 
 
 External Lateral, by anterior (1. talofibulare anterius), posterior (1. 
 talofibulare posterius) and middle (1. calcaneofibulare) fasciculi, from 
 the external malleolus to the astragalus and os calcis. 
 
 The Tarsal Articulations are connected by the following-named liga- 
 ments, viz., the 
 
 Calcaneo-astragaloid 3, external, internal and posterior, connecting the 
 
 os calcis with the astragalus. 
 Calcaneo-cuboid 4, superior, internal, long and short, connecting the 
 
 os calcis with the cuboid. 
 Calcaneo-navicular 2, superior and inferior, connecting the os calcis 
 
 with the scaphoid or navicular bone. 
 Astragalo-navicular, superior, connecting the astragalus with the 
 
 scaphoid or navicular bone. 
 Dorsal and Plantar Ligaments, connecting the scaphoid with the three 
 
 cuneiform and with the cuboid, the three cuneiform with each other, 
 
 and the external cuneiform with the cuboid. 
 Interosseous Ligaments, connecting the os calcis with the astragalus, 
 
 the scaphoid with the cuboid, the cuneiform bones with each other, 
 
 and the external cuneiform with the cuboid. 
 Nerves. All the joints of the tarsus are supplied by the anterior tibial 
 
 nerve. 
 
 The Tarso-metatarsal Articulations are 5 arthrodial joints formed by 
 the bases of the metatarsal bones with the adjacent bones of the tarsus, the 
 2d metatarsal bone articulating with all 3 cuneiform in the recess formed 
 by the shortness of the second cuneiform. They are united by Dorsal, 
 Plantar, and 3 Interosseous Ligaments. The 2d metatarsal bone has 3 
 dorsal ligaments, i from each cuneiform bone. The interosseous ligaments 
 pass from the 2d and 3d metatarsal bones to the internal and external 
 cuneiform. 
 
MUSCLES AND FASCIA 73 
 
 Synovial Membranes of the Tarsus and Metatarsus are 6 in number, 
 and are situated as follows, viz. 
 First, between the os calcis and the astra'galus, behind the interosseous 
 
 ligament. 
 Second, between the same bones in front of the interosseous ligament, 
 
 also between the astragalus and the scaphoid. 
 Third, between the os calcis and the cuboid. 
 
 Fourth, between the scaphoid and the 3 cuneiform bones, running back- 
 ward between the scaphoid and the cuboid, forward between the 
 cuneiform bones, between the external cuneiform and the cuboid, 
 between the middle and external cuneiform and the bases of the 2d 
 and 3d metatarsal, passing also between the bases of these bones and 
 the 4th metatarsal. 
 Fifth, between the internal cuneiform and the base of the ist metatarsal 
 
 bone. 
 Sixth, between the cuboid and the 4th and 5th metatarsal bones, also 
 
 running forward between their bases. 
 
 The Metatarso -metatarsal Articulations. The metatarsal bones are 
 connected together, except the first, at their bases by Dorsal, Plantar, and 
 Interosseous Ligaments. The base of the first metatarsal is not connected 
 with the base of the second by any ligaments, resembling the thumb in this 
 respect. 
 
 Remaining Articulations of the Foot. The metatarso-phalangeal 
 and the phalangeal articulations are similar to those in the hand, each 
 having a Plantar and 2 Lateral Ligaments. The extensor tendons supply 
 the places of the posterior ligaments. 
 
 THE MUSCLES AND FASCLE 
 
 The Muscles are the active organs of locomotion, formed of bundles ol 
 reddish fibres endowed with the property of shortening themselves upon 
 irritation, which is called muscular contractility, and chemically consisting 
 of 75 per cent, of water, 20 of proteids, 2 of fat, i of nitrogenous extractives 
 and carbohydrates, and 2 per cent, of salts, mainly potassium phosphate 
 and carbonate. 
 
 The Muscles are divided into 2 great classes, Voluntary, Striped, or 
 Muscles of animal life, comprise those which are under the control of the 
 will. Involuntary, Unstriped, or Muscles of organic life, are those which 
 are not under the control of the will. 
 
 Voluntary Muscular Fibre consists of fasciculi enclosed in a delicate 
 web, the perimysium, connected together by a delicate connective tissue, 
 
74 HUMAN ANATOMY 
 
 the endomysium, aggregated into muscular fibres, from ^ O o inch to ^oo 
 inch in diameter, which are enclosed in tubular sheaths, the sarcolemma, 
 and are marked by fine stria *passing around them transversely or some- 
 what obliquely. The fasciculi are formed of longitudinal fibrillae or 
 sarcostyles, made up of successive portions called sarcomeres, each of which 
 consists of a central dark part the sarcous element, and a clear layer which 
 is most visible when the fibre is extended (Schafer). 
 
 Involuntary Muscular Fibre is made up of spindle-shaped cells, the 
 contractile fibre-cells, averaging ^50 inch long and ^40 oo inch broad, col- 
 lected into bundles and held together by a cement-like substance. These 
 are aggregated into larger bundles or flattened bands, bound together by 
 ordinary connective tissue. Involuntary muscular fibres are found in the 
 walls of the alimentary canal, in the posterior wall of the trachea, in the 
 bronchi, the ducts of certain glands, in the ureters, bladder, urethra, 
 genitalia of both sexes, walls of all arteries and most veins and lymphatics, 
 in the iris and ciliary muscle, and in the skin. 
 
 *j 7 Tendons and Aponeuroses. Tendons are white, glistening cords or 
 
 ' bands formed of white fibrous tissue almost entirely, have few vessels and 
 
 no nerves in the smaller ones. They serve to connect the muscles with 
 
 the structures on which they act. Aponeuroses are fibrous membranes, 
 
 of similar structure and appearance, and serve the same purpose. 
 
 Fasciae are laminae of variable thickness which invest (fascia, a bandage) 
 the softer structures. The superficial fascia or subcutaneous tela consists 
 of two layers, a superficial fatty layer (panniculus adiposus) which is 
 closely adherent to the true skin, covering over almost the entire body. 
 Except on the eyelids, penis, and scrotum, it contains much fat. The 
 deep layer of the superficial fascia is a fibro-muscular layer (panniculus 
 carnosus) it envelops the entire trunk. On the sides of the neck and upper 
 part of the chest it is muscular and is there called the platysma, it is also 
 muscular in the scrotum where it is called the dartos. The deep fascia 
 is of aponeurotic structure, dense, inelastic, and fibrous, ensheathing the 
 muscles and affording some of them attachment, it also forms the sheaths 
 of the vessels and nerves, and binding down the whole into a shapely mass. 
 
 Muscles are attached to the periosteum and perichondrium of bone and 
 cartilage, to the subcutaneous areolar tissue, and to ligaments. In the 
 latter case only are their tendons in direct contact with the tissue on which 
 they are to act. 
 
 Double-bellied Muscles are 4 in number, the occipito-frontalis, 
 digastric, omo-hyoid, and the diaphragm. 
 
MUSCLES OF THE HEAD 75 
 
 MUSCLES OF THE HEAD 
 
 CRANIAL REGION 
 
 Occipito-frontalis (a) , arises/row the external two-thirds of the superior 
 curved line of the occipital bone and the mastoid process of the temporal; 
 also from the pyramidalis nasi, corrugator supercilii, and orbicularis pal- 
 pebrarum fibres; and is inserted into an aponeurosis or "galea capitis," 
 which covers the vertex of the skull. Action, chiefly as a muscle of facial 
 expression. Nerves, the frontal portion (m. frontalis) by the facial nerve, 
 the occipital portion (m. occipitalis) by the posterior auricular branch 
 of the facial. 
 
 AURICULAR REGION 
 
 I Auricularis anterior, or Attrahens Auriculam, from the lateral cranial 
 aponeurosis: into the helix of the ear anteriorly. Action, to draw the 
 pinna forward. Nerve, temporal branch of the facial. 
 
 ? Auricularis superior, or Attollens Auriculam, -from the occipito-frontalis 
 aponeurosis: into thejginna of the ear superiorly. Action, to raise the 
 pinna. Nerve, temporal branch of the facial. 
 
 Auricularis posterior, or Retrahens Auriculam, from the mastoid process 
 of the temporal bone: into the concha. Action, to retract the pinna. 
 Nerve, posterior auricular branch of the facial. 
 
 PALPEBRAL REGION 
 
 Orbicularis Palpebrarum (m. orbicularis oculi), from the internal 
 angular process of the irontal bone, the nasal process of the superior 
 maxillary, and the borders of the tendo oculi; into the skin of the 
 eyelids, forehead, temple, and cheek, blending with the occipito-frontalis 
 and the corrugator supercilii. Action, to close the eyelids. Nerve, 
 facial; perhaps also the 3d nerve. 
 
 Corrugator Supercilii, /row the inner end of the superciliary ridge of the 
 frontal bone: into the orbicularis palpebrarum. Action, to draw eye- 
 brow downward and inward. Nerve, facial; perhaps by the 3d nerve. 
 
 Tensor Tarsi (is classed by some as a portion (pars lacrimalis) of the 
 orbicularis) it arises, from the crest of the lacrimal bone into the 
 tarsal cartilages by two slips. Action, to compress the puncta lacri- 
 malia against the globe of the eye and to compress the lacrimal sac. 
 Nerve, facial; perhaps also the 3d nerve. 
 
70 HUMAN ANATOMY 
 
 ORBITAL REGION 
 
 Levator Palpebrae Superioris (9), from the lesser wing of the sphenoid: 
 
 into the upper tarsal cartilage. Action, to lift the upper lid. Nerve, 
 
 3d cranial, or motor oculi. 
 The fibrous ring (annulus tendineus communis) from which arise the 
 
 recti oculi muscles, is divisible into an upper common tendon and a 
 
 lower common tendon. 
 
 Rectus Superior (5), from the superior common tendon (ligament of 
 Lock wood) : into the sclerotic coat. Action, to rotate the eyeball upward. 
 Nerve, 3d cranial. 
 
 Rectus Inferior (4), from the inferior common tendon (ligament of Zinn) : 
 c. into the sclerotic coat. Ac- 
 
 f Itj. 42. 
 
 lion, to rotate the eyeball 
 downward. Nerve, 3d 
 cranial. 
 
 Rectus Interims (3), from 
 the inferior common ten- 
 don (ligament of Zinn) : into 
 the sclerotic coat. Action, 
 to rotate the eyeball in- 
 ward. Nerve, 3d cranial. 
 Rectus Externus (or lateralis) 
 (2), by 2 heads, the upper 
 from the superior common 
 tendon (ligament of Lock- 
 wood), the lower from the 
 inferior common tendon 
 (ligament of Zinn) and a 
 
 bony process at lower margin of the sphenoidal fissure: into the scle- 
 rotic coat. Action, to rotate the eyeball outward. Nerve, 6th cranial, 
 or abducens. 
 Between the 2 heads of the external rectus pass the 3d, nasal branch of the 
 
 5th, and 6th cranial nerves, and the ophthalmic vein. 
 Obliquus Oculi Superior (6), from about a line above the inner margin 
 of the optic foramen, its tendon passing through a pulley (7) near the 
 internal angular process of the frontal bone and thence beneath the 
 rectus superior: into the sclerotic coat at right angles to the insertion of 
 the rectus superior. Action, to rotate the eyeball on its antero-posterior 
 axis. Nerve, 4th cranial, or patheticus. 
 
MUSCLES OF THE HEAD 
 
 77 
 
 FIG. 43. 
 
 Obliquus Oculi Inferior (S),from the orbital plate of the maxilla: into 
 the sclerotic coat below the insertion of the external rectus and at 
 right angles thereto. Action, to rotate the eye on its antero-posterior 
 axis. Nerve, 30! cranial. 
 
 NASAL REGION 
 
 Pyramidalis Nasi (m. procerus) (c), from the occipito-frontalis: into 
 
 the compressor naris. Action, to depress the eyebrow. Nerve, facial. 
 Levator Labii Superioris Alaeque Nasi (caput angulare of the m. 
 
 quadratus labii superioris) (e), from the nasal process of the maxilla 
 
 bone: into the cartilage of the ala of the nose and into the upper lip. 
 
 Action, to elevate the upper lip, and dilate the nostril. Nerve, facial. 
 Dilator Naris Anterior, from the car- 
 tilage of the ala: into the border of 
 
 its integument. Action, to dilate 
 
 the nostril. Nerve, facial. 
 Dilator Naris Posterior, from the 
 
 nasal notch of the maxilla and the 
 
 sesamoid cartilages: into the integu- 
 ment a,t the margin of the nostril. 
 
 Action, to dilate the nostril. Nerve, 
 
 facial. 
 Compressor Nasi (m. nasalis) (</), 
 
 from the maxilla above the incisive 
 
 fossa: into the fibro-cartilage of the 
 
 nose, being continuous with its fellow 
 
 and the pyramidalis nasi aponeu- 
 
 rosis. Action, to dilate the nostril. 
 
 Nerve, facial. 
 Compressor Narium Minor,; from 
 
 the alar cartilage: into the skin at the end of the nose. 
 
 dilate the nostril. Nerve, facial. 
 Depressor Alae Nasi (m. depressor septi), from the incisive fossa of 
 
 the maxilla: into the septum and ala of the nose. Action, to contract 
 
 the nostril. Nerve, facial. 
 
 MAXILLARY REGION 
 
 Levator Labii Superioris (caput infra-orbitale of the m. quadratus labii 
 superioris) (/), from the lower margin of the orbit: into the upper 
 lip. Action, to elevate the lip. Nerve, facial. 
 
 Action, to 
 
78 HUMAN ANATOMY 
 
 LevatorAnguliOris (m. Caninus) (o),fromthe canine fossa of the maxilla: 
 into the angle of the mouth. Action, as named. Nerve, facial. 
 
 Zygomaticus Major (m. zygomaticus) (h),from the malar bone: into 
 the angle of the mouth. Action, to raise the lip outward. Nerve, 
 facial. 
 
 Zygomaticus Minor (caput zygomaticum of the m. quadratus labii 
 superioris) (g), from the malar bone anteriorly: into the angle of the 
 mouth, blending with the levator labii superioris. Action, to raise 
 the lip outward. Nerve, facial. 
 
 Musculus Quadratus Labii Superioris (B. N. A.) comprises three muscles, 
 each one of which is called a head or caput. The three heads are called 
 respectively, caput angiilare, caput infra-orbitale, and caput zygo- 
 maticum. The regular names for these three heads, are, in the order 
 given, levator labii superioris alaequae nasi, levator labii superioris, 
 and zygomaticus minor. 
 
 MANDIBULAR REGION 
 
 Levator Menti (m. mentalis) (m), from the incisive fossa of the mandible 
 
 bone: into the integument of the chin. Action, as named. Nerve, 
 
 facial. 
 Depressor Labii Inferioris (m. quadratus labii inferioris) (I), from the 
 
 external oblique line of the mandible: into the lower lip. Action, as 
 
 named. Nerve, facial. 
 Depressor Anguli Oris (m. triangularis) (), from the external oblique 
 
 line of the mandible: into the angle of the mouth. Action, as named. 
 
 Nerve, facial. 
 
 BUCCAL REGION 
 
 Orbicularis Oris (&), is the sphincter of the lips, the upper portion, in 
 the upper lip, is attached in the mid-line to the septum of the nose 
 (naso-labial band), laterally it is attached to the incisor fossa of the 
 maxilla (superior incisive bundle). The lower portion, in the lower 
 lip, is attached to the mandible immediately above the mental pro- 
 tuberance (inferior incisive bundle). At the corner of the mouth, 
 the upper and lower portions decussate with each other and, deeply, 
 with the buccinator. Action, to close the mouth. Nerve, facial. 
 
 Buccinator (j),from the alveolar arches of both the maxillae and mandible 
 and from the pterygo-mandibular ligament: into the orbicularis oris. 
 It forms the lateral walls of the mouth; it is pierced by the parotid duct. 
 
MUSCLES OF THE EAR 79 
 
 Action, to compress the cheeks. Nerves (motor) facial, and (sensory) 
 the long buccal branch of the mandibular. 
 
 Risorius, from the fascia over the masseter muscle: into the angle of the 
 mouth. Action, the laughing muscle. Nerve, facial. 
 
 TEMPORO-MANDIBULAR REGION 
 
 Masseter (i), from the anterior two-thirds and the inner surface of the 
 zygoma and the malar process of the maxilla: into almost all of the outer 
 surface of the angle, ramus, and coronoid process of the lower jaw. 
 A ction, to raise the back part of the lower jaw; a muscle of mastication. 
 Nerve, masticator portion of mandibular. 
 
 Temporal, from the temporal fossa and temporal fascia: into the coronoid 
 process of the mandible. Action, to bring the incisor teeth together; 
 the biting muscle. Nerve, masticator portion of mandibular. 
 
 PTERYGO-MANDIBULAR REGION 
 
 External Pterygoid, by 2 heads, the upper, from the pterygoid ridge on 
 the greater wing of the sphenoid, the lower from the external pterygoid 
 plate, and the tuberosities of the palate and maxilla: into a depression in 
 front of the condyle of the mandible, and the inter-articular fibro- 
 cartilage. Action, to draw the jaw forward; a triturating muscle of 
 mastication. Nerve, masticator portion of mandibular. 
 
 Between the two heads of the external pterygoid muscle passes the internal 
 maxillary artery. 
 
 Internal Pterygoid, from the pterygoid fossa of the sphenoid bone, and 
 the tuberosity of the palate: into the angle and inner surface of the 
 ramus of the jaw, as high as the dental foramen. Action, raises and 
 draws forward the lower jaw; a triturating muscle of mastication. 
 Nerve, masticator portion of mandibular. 
 
 MUSCLES OF THE EAR 
 
 The muscles of the ear include those of the pinna and those of the tym- 
 panum. The former are divided into two sets: Extrinsic, the attra- 
 hens, attollens and retrahens auriculam (see page 75); and the Intrinsic, as 
 follows: 
 
 INTRINSIC MUSCLES OF THE PINNA 
 
 Helicis Major, from the cauda helicis: into the anterior border of the 
 helix. Nerve, facial. 
 
8o HUMAN ANATOMY 
 
 Helicis Minor, an oblique fasciculus which covers the crus helicis. 
 Nerve, facial. 
 
 Tragicus, a short, vertical band of muscular fibres, on the outer surface of 
 the tragus. Nerve, facial. 
 
 Antitragicus, from the antitragus: into the cauda helicis and antihelix. 
 Nerve, facial. 
 
 Transversus Auriculae, on the cranial surface of the pinna, from the con- 
 vexity of the concha: into the prominence corresponding to the groove of 
 the helix. Nerve, facial. 
 
 Obliquus Auriculae. from the upper and back part of the concha: into the 
 convexity immediately above it. Nerve, facial. 
 
 MUSCLES OF THE TYMPANUM 
 
 i Tensor Tympani, from the under surface of the petrous portion of the 
 temporal bone, the cartilaginous Eustachian tube, and its own osseous 
 canal: into the handle of the malleus. Action, to draw the membrana 
 tympani inward and tense. Nerve, branch from otic ganglion. 
 
 Laxator Tympani, from the base of the alar spine of the sphenoid, its ten- 
 don passing through the petro-tympanic fissure to be attached to the 
 processus gracilis (anterior processus) of the malleus. Nerve, branch 
 from otic ganglion (see page 301 ). 
 
 Stapedius, from the interior of the pyramid, through the orifice at its 
 apex: into the neck of the stapes. Action, to rotate the base of the 
 stapes and compress the contents of the vestibule. Nerve, tympanic 
 branch of the facial. 
 
 MUSCLES OF THE NECK 
 
 SUPERIOR CERVICAL REGION 
 
 / Platysma Myoides (panniculus carnosus), is a muscular fascia covering 
 the pectoral and cervical region; it is loosely attached to the lower jaw, 
 the angle of the mouth, the skin, and the cellular tissue of the face. 
 Action, to wrinkle the skin, and depress the mouth. Nerve, facial. 
 
 Sterno-cleido-mastoid (n), by two heads from the sternum (12) and the 
 clavicle (13) at its inner third: into the mastoid process of the temporal 
 bone, and the outer half of the superior curved line of the occipital. Ac- 
 tion, to depress and rotate the head. Nerves, spinal accessory, and deep 
 branches of the cervical plexus. 
 
MUSCLES OF THE NECK 
 
 8l 
 
 INFRA-HYOID REGION 
 
 Sterno-hyoid (14), from the posterior surface of the sternum and the 
 sternal end of the clavicle: into the body of the hyoid bone. Action, to 
 depress the hyoid bone. Nerve, a branch from the communicating loop 
 (ansa hypoglossi) between the descendens and communicans hypoglossi. 
 
 Sterno-thyroid (m. sterno-thyreoideus) (i$),from the posterior surface 
 of the sternum and the cartilage of the ist rib: into the oblique line on 
 the ala of the thyroid cartilage. Action, to depress the thyroid (thy- 
 reoid) cartilage. Nerve, a branch from the communicating loop (ansa 
 hypoglossi) between the descendens and communicans hypoglossi. 
 
 FIG. 44- 
 
 Thyro-hyoid (m. thyreohyoideus) (16), from the oblique line on the thy- 
 roid cartilage: into the body and greater cornu of the hyoid bone. 
 Action, to depress the larynx and the hyoid bone. Nerve, hypoglossal. 
 
 Omo-hyoid (17, i8),from the upper border of the scapula and the trans- 
 verse ligament: into the body of the hyoid bone. It has a tendon in its 
 centre which is bound down to the clavicle and the ist rib by a loop of the 
 deep cervical fascia. Action, to depress the hyoid bone, and draw it 
 backward. Nerve, branch from the communicating loop (ansa hypo- 
 glossi) between the descendens and communicans hypoglossi. 
 6 
 
82 HUMAN ANATOMY 
 
 SUPRA-HYOID REGION 
 
 Digastric, by 2 bellies, the posterior one (i) from the digastric groove of 
 the mastoid process of the temporal bone; the anterior (2) from a fossa 
 on the inner surface of the mandible near its symphysis: into a cen- 
 . tral tendon (3) which perforates the stylo-hyoid muscle, and is bound 
 down to the body of the hyoid bone by an aponeurotic loop. Action, to 
 raise the hyoid bone and tongue. Nerves, anterior belly is supplied by a 
 branch of the mylo-hyoid nerve, the posterior belly by the facial nerve. 
 
 Stylo-hyoid (4), -from thestyloid process of the temporal bone near its 
 base: into the body of the hyoid bone. Action, to elevate and retract 
 the hyoid bone. Nerve, facial. This muscle is perforated by the 
 digastric. 
 
 Mylo-hyoid (5), -from the mylo-hyoid ridge of the lower jaw: into the 
 body of the hyoid bone and a median fibrous raphe line running from the 
 hyoid bone to the lower jaw. Action, elevates the hyoid bone and draws 
 it forward, also forms the floor of the mouth. Nerve, mylo-hyoid branch 
 of inferior dental (inferior alveolar). 
 
 Genio-hyoid (6), from the inferior genial tubercles (mental spines) of 
 the mandible into the body of the hyoid bone. Action, same as that of 
 the mylo-hyoid. Nerve, hypoglossal. 
 
 LINGUAL REGION 
 
 Genio-hyo-glossus (m. genioglossus), from the superior genial tubercles 
 (mental spines) of the mandible: into the body of the hyoid bone, the 
 side of the pharynx, and the whole length of the under surface of the 
 tongue, forming a fan-like muscle. Action, to retract and protrude 
 the tongue. Nerve, hypoglossal. 
 
 Hyo-glossus (8), from the side of the body of the hyoid bone, and the 
 whole length of its greater cornu: into the side of the tongue. Action, to 
 draw down the side of the tongue. Nerve, hypoglossal. 
 
 Chondro-glossus, sometimes described as a part of the hyo-glossus, from 
 the lesser cornu and the body of the hyoid bone: into the intrinsic mus- 
 cular fibres of the tongue, between the hyo-glossus and the genio-hyo- 
 glossus. Action, as the hyo-glossus. Nerve, hypoglossal. 
 
 Stylo-glossus (9), from the styloid process and the stylo-mandibular liga- 
 ment: into the side of the tongue and the hyo-glossus muscle. Action, 
 to elevate and retract the tongue. Nerve, hypoglossal. 
 
MUSCLES OF THE PHARYNX 83 
 
 Palato-glossus (m. glossopalatinus), is one of the muscles of the tongue, 
 serving to draw its base upward, but is described with the muscles of 
 the palatal region. 
 
 Lingualis (the tongue-muscle), in 4 strata, longitudinalis lingua 
 superior, composed of fibres passing forward and outward; stratum 
 derived principally from the extrinsic muscles, the stylo-glossus, hyo- 
 glossus, etc.; tr answer sus lingua and verticalis lingua, the latter 
 found only at the borders of the fore part of the tongue; longitudinalis 
 lingua inferior and fibres from the stylo-glossus. Action, to give the 
 tongue its various forms. Nerve, the hypoglossal is the motor nerve of 
 the tongue. 
 
 PHARYNGEAL REGION 
 
 Inferior Constrictor, from the sides of the cricoid and thyroid cartilages 
 into the fibrous raphe of the pharynx. Action, to contract the pharyn- 
 geal calibre. Nerves, branches from the pharyngeal plexus, external 
 laryngeal, recurrent laryngeal. 
 
 Middle Constrictor, -from the cornua of the hyoid bone and the stylo- 
 hyoid ligament : into the fibrous pharyngeal raphe. Action, to constrict 
 the pharynx. Nerves, branches from the pharyngeal plexus. 
 
 Superior Constrictor, from the lower third of the margin of the internal 
 pterygoid plate and its hamular process, the contiguous part of the 
 palate bone, the tendon of the tensor palati, the pterygo-mandibular 
 ligament, part of the alveolar process of the lower jaw and the side of the 
 tongue: into the fibrous pharyngeal raphe and the pharyngeal spine of 
 the occipital bone. Action, to constrict the pharynx. Nerves, branches 
 from the pharyngeal plexus. 
 
 Stylo-pharyngeus (io),from the inner side of the base of the styloid proc- 
 ess: into the constrictor and palato-pharyngeus muscles, and the thy- 
 roid cartilage. Action, to elevate the pharynx. Nerve, glosso-pharyn- 
 geal nerve which crosses this muscle in passing to the tongue. 
 
 PALATAL REGION 
 
 Levator Palati (m. Levator veli palatini), from the under surface of the 
 apex of the petrous portion of the temporal bone and from the Eusta- 
 chian tube: into the posterior surface of the soft palate. Action, to 
 elevate the soft palate. Nerve, pharyngeal plexus. 
 
 Tensor Palati (m. tensor veli palatini), 'from the scaphoid fossa and the 
 spine of the sphenoid bone and the Eustachian tube, reflected around 
 the hamular process: into the anterior surface of the soft palate, and the 
 
84 HUMAN ANATOMY 
 
 horizontal portion of the palate bone. Action, to make tense the soft 
 palate. Nerve, a branch from the otic ganglion. 
 
 Azygos Uvulae (m. uvulae), from the posterior nasal spine of the palate 
 bone, and from the soft palate: into the uvula. Action, possibly to 
 raise the uvula. This muscle is wrongly named, as it is a double muscle. 
 Nerve, pharyngeal plexus. 
 
 Palato-glossus (m. glossopalatinus) (constrictor isthmi faucium), front 
 the anterior surface of the soft palate on the side of the uvula: into the 
 side and dorsum of the tongue. Action, to constrict the fauces. It 
 forms the anterior pillar of the fauces. Nerve, pharyngeal plexus of the 
 spinal accessory. 
 
 Palato-pharyngeus (m. pharyngopalatinus) (posterior pillar of the fauces), 
 from the soft palate: into the side of the pharynx and the posterior 
 border of the thyroid cartilage, having joined the stylo-pharyngeus. 
 Action, to close the posterior nares. Nerve, pharyngeal plexus. 
 
 Salpingo-pharyngeus, from the Eustachian tube near its orifice: into the 
 posterior fasciculus of the palato-pharyngeus. A ction, to raise the upper 
 and lateral part of the pharynx. Nerve, pharyngeal plexus. 
 
 PREVERTEBRAL REGION 
 
 Rectus Capitis Anti'cus Major (m. longus capitis), from the anterior 
 tubercles of the transverse processes of the 3d, 4th, 5th, and 6th cervical 
 vertebrae by 4 slips: into the basilar process of the occipital bone. Action, 
 to flex and rotate the head. Nerves, first cervical and the loop between 
 it and the second. This muscle seems to be a continuation of the 
 scalenus anticus. 
 
 Rectus Capitis Anti'cus Minor (m. rectus capitis anterior}, from the 
 anterior surface of the lateral mass of the atlas, and the root of its trans- 
 verse process, into the basilar process of the occipital bone. Action, 
 to flex and rotate the head. Nerves, as the rectus capitis anticus major. 
 
 Rectus Capitis Lateralis, from the upper surface of the transverse process 
 of the atlas: into the jugular process of the occipital bone. Action, to 
 draw the head laterally. Nerves, as the preceding muscles. 
 
 Longus Colli, 3 portions, the superior oblique, from the anterior tubercles 
 of the transverse processes of the 3d, 4th, and 5th cervical vertebrae, into a 
 tubercle on the anterior arch of the atlas: inferior oblique, from the 
 bodies of the first 2 or 3 dorsal vertebrae, into the transverse processes of 
 the 5th and 6th cervical: vertical portion, from the bodies of the lower 
 3 cervical and upper 3 thoracic vertebrae, to the bodies of the 2d, 3d, and 
 
MUSCLES OF THE LARYNX AND EPIGLOTTIS 85 
 
 4th cervical. Action, to flex and slightly rotate the cervical portion of 
 the spine. Nerves, branches from the anterior divisions of the lower 
 cervical nerves. 
 
 LATERAL VERTEBRAL REGION 
 
 Scalenus Anti'cus (m. scalenus anterior) (20), from the transverse proc- 
 esses of the cervical vertebrae, from the 3d to the 6th inclusive: into 
 the scalene tubercle on the upper surface of the ist rib. Action, to 
 flex the neck laterally, or to raise the ist rib. Nerves, branches from the 
 lower cervical. (See Fig. 44.) 
 
 Scalenus Medius (22), -from the transverse processes of the lower 6 cer- 
 vical vertebrae: into the upper surface of the ist rib, behind the subcla- 
 vian groove. Action, same as the scalenus anticus. Nerves, branches 
 from the lower cervical. 
 
 Scalenus Posti'cus (m. scalenus posterior) (21), from the posterior tu- 
 bercles on the transverse processes of the lower 2 or 3 cervical vertebrae: 
 into the outer surface of the 2d rib, behind the serratus magnus. Action, 
 to flex the neck laterally, or to elevate the. 2d rib. Nerves, branches 
 from lower cervical. 
 
 MUSCLES OF THE LARYNX AND EPIGLOTTIS 
 
 MUSCLES OF THE VOCAL CORDS AND RIMA GLOTTIDIS 
 
 Crico-thyroid (m. cricothyreoideus), 'from the front and side of thecricoid 
 cartilage (6) : into the lower and inner borders of the thyroid cartilage 
 (c). Action, to elongate and make tense the 
 vocal cords. Nerve, external laryngeal. 
 
 Crico-arytenoideus Posticus (posterior),- from 
 the cricoid cartilage posteriorly : into the outer 
 angle of the base of the arytenoid cartilage. 
 Action, to rotate the arytenoid cartilages out- 
 ward and open the glottis, while keeping the 
 vocal cords tense. Nerve, recurrent laryngeal. 
 
 A small fasciculus, called Kerato-cricoideus, is 
 sometimes found below the arytenoideus, ex- 
 tending from the cricoid cartilage to the inferior 
 cornu of the thyroid. It occurs once in 5 cases, 
 usually on one side only, but occasionally on 
 both, and acts to fix the lower horn of the thyroid 
 cartilage backward and downward. [Sir Wm. 
 Turner.] 
 
86 HUMAN ANATOMY 
 
 Crico-arytenoideus Lateralis (d)from the upper border of the cricoid 
 cartilage laterally: into the outer angle of the base of the arytenoid 
 cartilage. Action, to rotate the arytenoid cartilages inward and close 
 the glottis. Nerve, recurrent laryngeal. 
 
 Arytenoideus, from the posterior surface and outer border of one ary- 
 tenoid cartilage: into the corresponding parts of the opposite cartilage. 
 A single muscle which fills the posterior concave surface of these carti- 
 lages. Action, by approximating the arytenoids, to close the back part 
 of the glottis. Nerves, internal and recurrent laryngeal. 
 
 A fairly constant muscle, the Arytenoideus rectus, is found beneath the ary- 
 tenoideus, extending from the posterior surface of the arytenoid carti- 
 lage to the posterior surface of the cartilage of Santorini [Luschka]. 
 v Thyro-arytenoideus (e), from the receding angle of the thyroid cartilage 
 and the crico-thyroid membrane: into the base and anterior surface of 
 the arytenoid cartilage. Action, to shorten and relax the vocal cords by 
 approximating the cartilages. Nerve, recurrent laryngeal. 
 
 MUSCLES or THE EPIGLOTTIS 
 
 Thyro-epiglottideus, from the inner surface of the thyroid cartilage: 
 into the margin of the epiglottis and the aryteno-epiglottidean fold. 
 Action, a depressor of the epiglottis. Nerve, recurrent laryngeal. 
 
 Aryteno-epiglottideus Superior, from the apex of the arytenoid carti- 
 lage : into the aryteno-epiglottidean folds. A ction, to constrict the supe- 
 rior laryngeal aperture. Nerve, recurrent laryngeal. 
 
 Aryteno-epiglottideus Inferior, from the arytenoid cartilage anteriorly: 
 into the anterior surface of the epiglottis. Action, to compress the 
 sacculus laryngis. Nerve, recurrent laryngeal. 
 
 Another small muscle is frequently found, though rarely described in the 
 books, the Triticeo-glossus. It arises from the cartilaginous nodule in 
 the posterior thyro-hyoid ligament, and passes forward and upward to 
 enter the tongue along with the hyo-glossus muscle. [Bochdalek, jun.] 
 
 MUSCLES OF THE TRUNK 
 
 The muscles of the trunk may be arranged in four groups, corresponding 
 to the regions in which they are situated, viz. those of the Back, the 
 Thorax, the Abdomen, and the Perineum. 
 
 MUSCLES OF THE BACK 
 
 The muscles of the back are in seven layers; these muscles can be 
 divided into two groups. First, those that are appsndicular, i.e,, those 
 
MUSCLES OF THE BACK 87 
 
 that actuate the upper extremity, and second, those that are axial, i.e., 
 those that act on the pelvis, ribs, vertebrae, and skull. 
 
 The First or Appendicular Group constitutes the first two layers of the 
 muscles of the back. 
 FIRST LAYER, 
 
 Trapezius, and Latissimus Dorsi. 
 SECOND LAYER, 
 
 Levator Anguli Scapula (m. leva tor scapulas). 
 
 Rhomboideus Minor. 
 
 Rhomboideus Major. 
 The, Second or Axial Group includes the remaining five layers, two that 
 
 are superficial and three that are covered in and surrounded by the 
 
 lumbo-dorsal fascia (vertebral aponeurosis). 
 THIRD LAYER, 
 
 Serratus Posticus Superior (m. serratus posterior superior). 
 
 Serratus Posticus Inferior (m. serratus posterior inferior). 
 FOURTH LAYER, 
 
 Splenius Capitis. 
 
 Splenius Cervicis (splenius colli). 
 
 LUMBO-DORSAL FASCIA OR VERTEBRAL APONEUROSIS 
 
 FIFTH LAYER, consists of two distinct muscular masses, the sacro- 
 
 spinal mass and the semi-spinal mass both of which used to be in- 
 cluded by the term erector spinae mass. 
 
 The Sacrospinal Mass divides into three longitudinal bundles. 
 OUTER OR ILIO-COSTAL DIVISION, 
 
 Ilio-costalis Lumborum (ilio-costalis or sacro-lumbalis). 
 
 Ilio-costalis Dorsi (accessorius ad ilio-costalem). 
 
 Ilio-costalis Cervicis (cervicalis ascendens). 
 MIDDLE OR LONGISSIMUS DIVISION, 
 
 Longissimus Dorsi. 
 
 Longissimus Cervicis (trans versalis colli). 
 
 Longissimus Capitis (trachelo-mastoid). 
 INNER OR SPINAL DIVISION, 
 
 Spinalis Dorsi. 
 
 Spinalis Cervicis (spinalis colli). 
 THE SEMI-SPINAL MASS, 
 
 Semi-spinalis Dorsi. 
 
 Semi-spinalis Cervicis (semi-spinalis colli). 
 
 Semi-spinalis Capitis (complexus, the inner portion of which was 
 sometimes called the biventer cervicis). 
 
88 HUMAN ANATOMY 
 
 SIXTH LAYER, 
 
 Multifidus SpincB (m. multifidus). 
 Rotatores Spincz (mm. rotatores). 
 SEVENTH LAYER, 
 Inter- spin ales. 
 Inter-transversalss (mm. inter-transversarii). 
 
 THE SUB-OCCIPITAL MUSCLES 
 
 Rectus Capitis Posticus Major (m. rectus capitis posterior major). 
 Rectus Capitis Posticus Minor (m. rectus capitis posterior minor). 
 Obliquus Capitis Inferior. 
 Obliquus Capitis Superior. 
 Rectus Capitis Lateralis. 
 
 FIRST LAYER 
 
 Trapezius (i),-^ro^the inner third of the superior curved line of the oc- 
 cipital bone, theligamentum nuchae (2), the spinous processes of the last 
 cervical and all the thoracic vertebrae, and the supra-spinous ligament : 
 into the outer third of the posterior border of the clavicle, the superior 
 margin of the acromion process, the whole length of the superior border 
 of the spine of the scapula (3), and a tubercle at its inner extremity. 
 Action, to draw the head backward. Nerves, spinal accessory (n. 
 accessorius) , cervical plexus. 
 
 Lie AMENTUM NUCHAE (2), from the external occipital protuberance: to 
 the spines of the cervical vertebrae, from the 2d to the yth inclusive. 
 
 Latissimus Dorsi (4), by an aponeurosis from the spines of the 6 lower 
 thoracic and the lumbar and sacral vertebrae, the supra-spinous ligament, 
 the crest of the ilium and the lower 3 or 4 ribs: into the bicipital groove of 
 the humerus. A ction, the cursor ani muscle, drawing the arm downward 
 and backward; or raising the lower ribs and drawing the trunk forward. 
 Nerve, the middle or long subscapular. 
 
 SECOND LAYER. 
 
 Levator Anguli Scapulae (m. levator scapulae) (10), by 4 slips from the 
 transverse processes of the atlas and 3 upper cervical vertebrae: into the 
 vertebra^ border of the scapula. Action, as named. Nerves, branches 
 from the anterior divisions of the 3d, 4th and 5th cervical nerves. 
 
 Rhomboideus Minor (n), from the ligamentum nuchae (2) and spines of 
 the 7th cervical and ist thoracic vertebrae: into the smooth surface at 
 the root of the spine of the scapula. Action, to draw the scapula back- 
 
MUSCLES OF THE BACK 89 
 
 ward and upward. Nerve, branches from the anterior division of the 
 5th cervical. 
 
 Rhomboideus Major (12), from the spines of the upper 4 or 5 thoracic 
 vertebrae and the supra-spinous ligament : into the scapula at the root of 
 
 FIG 46. 
 
 its spine and inferior angle, by a tendinous arch. Action, to draw the 
 scapula upward and backward. Nerve, anterior division of the 5th 
 cervical. 
 
 THIRD LAYER 
 
 Serratus Posti'cus Superior (m. serratus posterior superior) , from the 
 ligamentum nuchae (a), and spines of the yth cervical and upper 2 or 3 
 
90 HUMAN ANATOMY 
 
 thoracic vertebrae: into the upper borders of the 2d, 36, 4th, and 5th 
 ribs, by 4 digitations. A ction, to raise these ribs in inspiration. Nerves, 
 external posterior branches of the upper thoracic nerves. 
 
 Serratus Posti'cus Inferior (m. serratus posterior inferior) (i6)from 
 the spines of the last 2 thoracic and first 3 lumbar vertebrae: into the 
 lower borders of the lower 4 ribs, by 4 digitations. Action, to depress 
 these ribs in expiration. Nerves, external posterior branches of the 
 lower thoracic nerves. 
 
 FOURTH LAYER 
 
 Splenius (Capitis et Cervicis) (14), from the lower half of the ligamentum 
 nuchae (2), the last cervical and upper 6 thoracic spines, and the supra- 
 spinous ligament: the S. capitis (13) into the mastoid process of the 
 temporal bone and a rough surface below the superior nuchal 
 line of the occipital bone, the 5. cervicis or colli (14) into the transverse 
 processes of the upper 2 or 3 cervical vertebrae. Action, to draw the 
 head backward and the neck erect. Nerves, external posterior branches 
 of the cervical nerves. 
 
 Lumbo-dorsal Fascia or Vertebral Aponeurosis, consists of three layers. 
 Posterior layer is the most extensive, it is attached to the spines of 
 sacral, lumbar, and thoracic vertebrae, its fibres pass out laterally to 
 blend in the lumbar region first with the middle layer and further out, at 
 the origin of the transversalis abdominis, it blends with the anterior 
 layer. The middle layer is in the interval between the sacro-spinal 
 mass and the quadratus lumborum. It is attached to the tips of the 
 transverse processes of the lumbar vertebras. The anterior layer forms 
 the front part of the sheath of the quadratus lumborum, it then passes 
 between that muscle and the psoas to become attached to the front of 
 the bases of the transverse processes of the lumbar vertebrae. 
 
 FIFTH LAYER. (See Fig. 47) 
 
 Sacro-spinalis or Erector Spinae (i), from the sacro-iliac groove, and by 
 the lumbo-sacral tendon from the sacral, lumbar and lower 2 thoracic 
 spines, the iliac crest, and the posterior eminences of the sacrum : divides 
 into the ilio-costalis (2) and longissimus dorsi (3) muscles. Action, to 
 erect the spine and bend the trunk backward. Nerves, external pos- 
 terior branches of the lumbar nerves. 
 
MUSCLES OF THE BACK QI 
 
 ILIO-COSTAL DIVISION 
 
 Ilio-costalis Lumbonun (sacro-lumbalis) (2), the external portion of the 
 erector spinae: into the inferior borders of the angles of the lower 6 or 7 
 ribs. Action, as the erector spinae. Nerves, branches of the thoracic. 
 
 Ilio-costalis Dorsi or Musculus Accessorius ad Hio-costalem (2), from 
 the angles of 6 lower ribs: into the angles of upper 6 ribs. Action, as the 
 erector spinae. Nerves, branches of the 
 thoracic. 
 
 Ilio-costalis Cervicis or Cervicalis Ascen- 
 dens (s),from the angles of upper 4 
 or 5 ribs: into the transverse processes 
 of the 4th, 5th, and 6th cervical verte- 
 brae. Action, to keep the neck erect. 
 Nerves, branches of the cervical. 
 
 LONGISSIMUS DIVISION 
 
 Longissimus Dorsi (3). is the middle 
 and largest portion of the erector spinae, 
 and is inserted into the transverse and 
 articular processes of the lumbar verte- 
 brae, into the tips of the transverse proc- 
 esses of all the thoracic vertebrae, and 
 into from lower 7 to n ribs between 
 their tubercles and angles. Action, as 
 the erector spinae. Nerves, branches of 
 the lumbar and thoracic nerves. 
 
 Longissimus Cervicis or Transversalis 
 Colli (6), from the transverse processes 
 of the upper 6 thoracic vertebrae; into the 
 transverse processes of the cervical verte- 
 brae (9), from the 2d to the 6th inclusive. 
 Action, to keep the head erect. Nerves, 
 branches of the cervical. 
 
 Longissimus Capitis or Trachelo-mastoid 
 (7), from the transverse processes of 
 
 the upper 5 or 6 thoracic vertebrae, and the articular processes of the 
 lower 3 or 4 cervical: into the posterior margin of the mastoid proc- 
 ess of the temporal bone. Action, to steady the head. Nerves, 
 branches of the cervical. 
 
92 HUMAN ANATOMY 
 
 SPINAL MASS 
 
 Spinalis Dorsi, from the last 2 thoracic and first 2 lumbar spines: into 
 all the remaining thoracic spines. Action, to erect the spinal column. 
 Nerves, branches of the thoracic. 
 
 Spinalis Cervicis or Spinalis Colli, from the 5th, 6th and 7th cervical 
 spines, sometimes from the ist and 2d thoracic: into the spine of the axis 
 and occasionally into the spines of the next two vertebrae below. A ction, 
 to steady the neck. Nerves, branches of the cervical. [This muscle is 
 frequently absent.] 
 
 Semi -spinalis Capitis or Complexus (8), by 7 tendons from the tips of 
 the transverse processes of the ;th cervical and upper 6 or 7 thoracic 
 vertebrae, and from the articular processes of the 4th, 5th, and 6th cer- 
 vical: into the inner depression between the curved (nuchal) lines of the 
 occipital bone. Action, to retract and rotate the head. Nerves, sub- 
 occipital, great occipital, and branches of the cervical nerves. 
 
 Bivenler Crevicis, is the inner part of the Complexus, from the trans- 
 verse processes of upper 2 to 4 thoracic vertebrae: into the superior curved 
 line of the occipital bone. Action, as the complexus. Nerves, branches 
 of the cervical. 
 
 Semi -spinalis Dorsi (10), from the transverse processes of the thoracic 
 vertebrae, from about the sth to the nth: into the last 2 cervical and 
 upper 4 thoracic spines. Action, to erect the spinal column. Nerves, 
 branches of the thoracic nerves. 
 
 Semi -spinalis Cervicis or Semi-spinalis Colli (n), from the transverse 
 processes of the upper 5 or 6 thoracic vertebrae: into the 2d, 3d, 4th, 
 and 5th cervical spines. Action, to erect the spinal column. Nerves, 
 branches of the cervical. 
 
 SIXTH LAYER 
 
 Multifidus Spinae (m. multifidus) (i6],from the back of the sacrum, pos- 
 terior superior spine of the ilium, posterior sacro-iliac ligaments, ar- 
 ticular processes of lumbar and lower 3 or 4 cervical vertebrae, and the 
 transverse processes of the thoracic: into the spines of the next 4 vertebrae 
 above. Action, to erect and rotate the spinal column. Nerves, branches 
 of the spinal nerves. 
 
 Rotatores Spinae (mm. rotatores), from the transverse processes of the 
 thoracic vertebrae, from the 2d to the i2th inclusive: each into the 
 lamina of the next thoracic vertebrae above. Action, to rotate the 
 spinal column. Nerves, branches of the posterior thoracic. 
 
SUBOCCIPITAL AND THORACIC MUSCLES 93 
 
 Inter-spinales, placed in pairs between the spines of contiguous vertebrae, 
 6 pairs in the cervical region, 3 in the thoracic, 4 sometimes 6 in the 
 lumbar. Nerves, branches of the posterior spinal. 
 
 Extensor Coccygis, from the last bone of the sacrum or first of the coccyx : 
 into the lower part of the coccyx, posteriorly. Action, as named. 
 Nerves, branches of the posterior sacral. 
 
 Inter -transversales (mm. intertransversarii) (18), placed between the 
 transverse processes of contiguous vertebrae, 7 in the cervical region, 
 12 in the thoracic, and 4 in the lumbar. Nerves, branches of the pos- 
 terior spinal. 
 
 SUBOCCIPITAL MUSCLES 
 
 Rectus Capitis Posti'cus Major (m. rectus capitis posterior major) (13), 
 from the spine of the axis: into the inferior curved or nuchal line of the 
 occipital bone and the surface below. Action, to rotate the head. 
 Nerves, suboccipital. 
 
 Rectus Capitis Posti'cus Minor (m. rectus capitis posterior minor) (12), 
 from the tubercle on the posterior arch of the atlas: into a rough surface 
 between the foramen magnum and the inferior curved or nuchal line of 
 the occipital bone. Action, to draw the head backward. Nerves, 
 suboccipital. 
 
 Obliquus Capitis Inferior (15), from the spinous process of the axis: 
 almost horizontally into the transverse process of the atlas. Action, to 
 rotate the atlas and cranium. Nerves, suboccipital. 
 
 Obliquus Capitis Superior (14), from the transverse process of the atlas, 
 upward and inward into the occipital bone between the curved lines. 
 Action, draws the head backward. Nerves, suboccipital. 
 
 Rectus Capitis Lateralis, from upper surface of lateral mass of atlas: into 
 under surface of the jugular process of the occipital bone. Action, to 
 flex the head laterally. Nerve, the anterior branch of the first cervical. 
 
 MUSCLES OF THE THORAX 
 
 External Intercostals, each from the lower border of each rib: into 
 the upper border of the next rib below directed obliquely downward and 
 forward. Action, to raise and evert the ribs in inspiration. Nerves, 
 intercostal. 
 
 Internal Intercostals, each from the ridge on the inner surface of each rib: 
 into the upper border of the rib below, directed obliquely downward and 
 
HUMAN ANATOMY 
 
 backward. Action, at sides of thorax to depress the ribs in expiration; 
 anteriorly they raise the costal cartilages. Nerves, intercostals. 
 
 Infra -costales, obliquely from inner surface of each rib: into the inner 
 surface of the ist, 2d, or 3d rib below. Action, muscles of inspiration. 
 Nerves, intercostal. [These muscles vary in number and length.] 
 
 Triangularis Sterni, from the posterior surface of the ensiform cartilage 
 and lower third of the sternum, also from the sternal ends of the costal 
 cartilages of the lower 3 or 4 true ribs: into the lower border and inner 
 surfaces of the 2d, 3d, 4th, sth, and 6th costal cartilages. A ction, to draw 
 down the cartilages in expiration. Nerves, intercostal. 
 
 FIG. 48. 
 
 Levatores Costarum (17 Fig. 47), each from the transverse process of the 
 7th cervical and upper n thoracic vertebrae: into the upper surface of 
 the next rib below, near its angle. Action, to raise the ribs. Nerves, 
 intercostal. 
 
 Diaphragm, from the ensiform cartilage (4), inner surfaces of lower 6 or 7 
 ribs, ligamenta arcuata (5), and by its crura (8, 10), from the bodies of 
 the lumbar vertebrae: into the central or cordiform tendon (2, 3). 
 Action, the great muscle of respiration and expulsion. Nerves, the two 
 phrenic, lower intercostals and phrenic plexus of the sympathetic. 
 
 OPENINGS OF THE DIAPHRAGM, include several small openings and 3 large 
 ones; the 
 
MUSCLES OF THE ABDOMEN 95 
 
 Aortic (n), in the middle line posteriorly, and behind the diaphragm; 
 
 transmits the aorta, vena azygos major, and thoracic duct. (Esopha- 
 
 geal (12), in the muscular structure, transmits the oesophagus and pneu- 
 
 mogastric nerves. Opening for the Vena Cava (13) is the highest, and has 
 
 4 tendinous margins. 
 The Right Cms (8) transmits the greater and lesser splanchnic nerves of 
 
 that side: the Left Cms (10), the greater and lesser splanchnic nerves of 
 
 the left side and the vena azygos minor. 
 Descent of the Diaphragm. Its central tendon does not descend during 
 
 inspiration, being connected with the deep cervical fascia by the fibrous 
 
 pericardium. 
 
 MUSCLES OF THE ABDOMEN 
 
 Obliquus Abdominis Externus- or External Oblique (12), from 8 lower 
 ribs by 8 fleshy digitations: into the anterior half of the outer lip of the 
 crest of the ilium, and by a broad aponeurosis (13) into the ensiform carti- 
 lage, linea alba, symphysis and spine of the pubes, and the ilio-pectineal 
 line. Its aponeurosis is continuous with that of the pectoralis major 
 above; below it forms Poupart's (1. inguinale) (14) and Gimbernat's 
 (1. lacunare) ligaments, and by the separation of its fibres the external 
 abdominal ring (15). Action, to compress the viscera, and flex the 
 thorax on the pelvis, and vice versa. Nerves, lower intercostal. 
 
 Obliquus Internus Abdominis or Internal Oblique (iS),from the lumbo- 
 dorsal fascia, the anterior two-thirds of the middle lip of the crest of the 
 ilium, and the outer half of Poupart's ligament (1. inguinale) : into the 
 cartilages of 4 lower ribs; by its aponeurosis into the linea alba; and 
 leaving an arched border (20) over the spermatic cord, by the conjoined 
 tendon (falx aponeurotica inguinalis) (19) with the transversalis into the 
 pubic crest and the pectineal line. Its aponeurosis passes in front of 
 the rectus abdominis; the lowermost portion, from the level of the semi- 
 lunar fold of Douglas downward, is called the conjoined tendon because 
 it serves for the transversalis as well. It blends in the linea alba with 
 the tendons of its fellow of the opposite side and the external oblique 
 and transversalis of both sides. Action, same as the external oblique. 
 Nerves, lower intercostals, ilio-hypogastric, and sometimes from the 
 ilio-inguinal. 
 
 Cremaster, from the inner part of Poupart's ligament (1. inguinale), form- 
 ing a series of loops along the outer side of the spermatic cord: into the 
 crest of the pubis and the front of the sheath of the rectus. Its origin 
 and insertion is precisely similar to that of the lower fibres of the internal 
 oblique, from which it is derived by the descent of the testicle. Action, 
 to raise the testicle. Nerve, the genital branch of the genito-crural. 
 
9 6 
 
 HUMAN ANATOMY 
 
 Transversalis Abdominis or Transversalis, from the outer third of 
 Poupart's ligament (1. inguinale), the anterior two-thirds of the inner 
 lip of the crest of the ilium, the cartilages of 6 lower ribs, and by its 
 dorsal aponeurosis (middle layer of the lumbodorsal fascia) from the 
 spines and transverse processes of the lumbar vertebrae: by its ventral 
 aponeurosis into the linea alba, and by the conjoined tendon (falx ap- 
 
 FIG. 49. 
 
 oneurotica inguinalis) (19) with the internal oblique, into the pubic crest 
 and the pectineal line. Its ventral aponeurosis passes behind the rectus 
 abdominis for about its upper three-fourths; the lower edge of this 
 tendon is the so-called "semilunar" fold of Douglas. Action, as the 
 external oblique. Nerves, as the internal oblique. 
 
 Rectus Abdominis (16), by 2 tendons from the pubic crest and the liga- 
 ments covering the symphysis; into the cartilages of the 5th, 6th, an^ 
 
MUSCLES OF THE PELVIC OUTLET 97 
 
 7th ribs. It lies in a sheath formed by the aponeuroses of the internal 
 
 oblique and transversalis muscles for its upper three-fourths, and is 
 
 crossed by 3 tendinous lines, the Linece Transverse. At its outer border 
 
 is a similar line placed vertically, the Linea Semilunaris, formed by the 
 
 blending of the aponeuroses of the internal oblique and transversalis. 
 
 Action, to flex the thorax on the pelvis and vice versa, also to compress the 
 
 abdominal viscera. Nerves, lower intercostal nerves. 
 
 Pyramidalis (17), lies in front of the rectus, but in the same sheath; arises 
 
 from the front of the pubic bone and the anterior pubic ligament: 
 
 into the linea alba, half-way to the umbilicus. Action, a tensor of the 
 
 linea alba. Nerves, lower intercostal nerves. 
 
 Quadratus Lumborum (19 Fig. 47), from the ilio-lumbar ligament, and 
 the adjacent 2 inches of the crest of the ilium: into one-half of the lower 
 border of the last rib, and the transverse processes of the 4 upper lumbar 
 vertebrae. Action, to flex the thorax laterally on the pelvis and vice 
 versa. Nerves, anterior branches of the last thoracic and ist lumbar. 
 The Psoas Magnus, the Psoas Parvus and the Iliacus muscles may be con- 
 sidered deep muscles of the abdomen, but are described with the muscles 
 of the lower extremity. 
 
 MUSCLES OF THE PELVIC OUTLET 
 
 The muscles of this region are situated at the pelvic outlet in the ischio- 
 rectal region and the perinaeum. 
 
 MUSCLES OF THE ISCHIO-RECTAL REGION 
 
 Corrugator Cutis Ani, A thin stratum of involuntary muscular fibre 
 around the anus, radiating from its orifice and serving to raise the skin 
 into ridges around the anal margin. 
 
 External Sphincter Ani (4), from the tip of the coccyx and superficial 
 fascia: into the tendinous center of the perinaeum. Action, to close the 
 anus. Nerves, inferior hemorrhoidal branch of the internal pudic, also a 
 branch from the anterior division of the 4th sacral. 
 
 Internal Sphincter Ani, an aggregation of the involuntary circular fibres 
 of the intestine, forming a muscular ring around the rectum about an 
 inch above the margin of the anus. Action, to occlude the anal aperture. 
 
 [A third sphincter, the Sphincter Tertius, from the sacrum, encircling the 
 rectum about 4 inches above the anus, was demonstrated by Velpeau, 
 Nelaton and Hyrtl, but is denied by other anatomists.] 
 7 
 
98 HUMAN ANATOMY 
 
 Levator Ani'(s), -from the body and ramus of the pubis posteriorly, the 
 pelvic fascia and the spine of the ischium: into the tendinous centre of 
 the perinaeum, the sides of the rectum (and vagina), apex of the coccyx, 
 and a fibrous raphe extending from the coccyx to the anus. Action, to 
 support the lower end of the rectum and vagina and the bladder, and 
 assist in forming the floor of the pelvis. Nerves, branches from the 4th 
 sacral and pudic. 
 
 Coccygeus, from the spine of the ischium and the lesser sacro-sciatic liga- 
 ment: into the margin of the coccyx and the side of the last sacral seg- 
 
 ment. Action, to support the 
 coccyx, and close the outlet of 
 the pelvis posteriorly. Nerves, 
 branches from the 4th and $th 
 sacral. 
 
 MUSCLES OF THE PERINEUM 
 IN THE MALE 
 
 Superficial Transversus Perinaei 
 
 (3), from the tuberosity of 
 the ischium: into the central 
 tendon of the perinaeum. Ac- 
 tion, to draw tense the central 
 tendon. Nerve, perinea! branch 
 ,of_the pudic. 
 
 Transversus Perinaei Profundus 
 (Compressor Urethrae), from 
 the junction of the rami of the 
 pubis and ischium: into its 
 fellow of the opposite side after 
 encircling the membranous portion of the urethrae. Action, to com- 
 press the veins of the penis, the membranous urethra, and Cowper's 
 glands. Nerve, perineal branch of the pudic. 
 
 Bullo-cavernosus (Accelerator Urinae) (i), from the central tendon of the 
 perinaeum and the median raphe anteriorly: the fibres spread over the 
 bulb, corpus spongiosum, corpus cavernosum and the dorsal vessels of 
 the penis. Action, to accelerate the flow of urine and erect the penis. 
 Nerve, perineal branch of the pudic. 
 
 ischio-cavernosus or Erector Penis (2), from the tuberosity and ramus 
 of the ischium and the crus penis: into the crus penis laterally and infe- 
 
 
MUSCLES OF THE UPPER EXTREMITY 99 
 
 riorly. Action, to maintain erection of the penis. Nerve, perineal branch 
 of the pudic. 
 
 FASCIAE OF THE PERINEUM, are described under the title Perinaeum at 
 the end of the book. 
 
 MUSCLES OF THE PERINEUM IN THE FEMALE 
 
 Superficial Transversus Perinsei (3), from the tuberosity of the ischium 
 internally: into the central point of the perinaeum, joining with its fellow 
 of the opposite side. Action, to fix the central tendinous point of the 
 perinaeum. Nerve, the perineal branch of the pudic. 
 
 Bulbo-cavernosus or Sphincter Vaginae, surrounds the orifice of the va- 
 gina, and is analogous to the accelerator urinae of the male. Arising 
 from the central tendon of the perinaeum, its fibres are inserted into the 
 corpora cavernosa of the clitoris, a fasciculus crossing over the body of 
 the organ so as to compress the dorsal vein. Action, to diminish the 
 orifice of the vagina. Nerve, perineal branch of the pudic. 
 
 Ischio-cavernosus or Erector Clitoridis, from the tuberosity andramus of 
 the ischium internally : into the crus clitoridis by an aponeurosis. A ction, 
 to erect the clitoris by retarding the return of its blood supply. Nerve, 
 perineal branch of the pudic. 
 
 Deep Transversus Perinsei or Compressor Urethras, from the margin of 
 the descending ramus of the pubic bone: into its fellow in front of the 
 urethra and into the wall of the vagina behind the urethra. Action, as 
 indicated by its name. Nerve, perineal branch of the pudic. 
 
 MUSCLES OF THE UPPER EXTREMITY 
 
 MUSCLES OF THE THORACIC REGION 
 
 JL '/ Pectoralis Major (i, 2, 3), from the sternal half of the clavicle, by an 
 / / aponeurosis from the front of the sternum as low as the 6th or yth rib, 
 the cartilages of all the true ribs (5), and the aponeurosis of the external 
 oblique: the fibres converge, cross and are inserted by a flat tendon (4) 
 into the external bicipital ridge (crest of the great tubercle) of the hu- 
 merus, having crossed the bicipital groove (intertubercular sulcus). 
 Action, to draw the arm forward and downward; also to elevate the ribs 
 in forced inspiration. Nerves, anterior thoracic. 
 
 Pectoralis Minor (6), from the 3d, 4th, and 5th ribs, and the intercostal 
 aponeurosis: into the coracoid process of the scapula. Action, to depress 
 
100 HUMAN ANATOMY 
 
 the point of the shoulder, also to elevate the ribs in forced inspiration. 
 Nerves, anterior thoracic. 
 
 Subclavius (7), from the cartilage of the ist rib: into a deep groove on the 
 under surface of the clavicle. Action, to draw the clavicle downward. 
 Nerve, a branch from the 5th cervical. 
 
 Serratus Magnus (m. serratus anterior), by 9 digitations (10) from the 
 8 upper ribs (the 2d rib having 2) and from the intercostal aponeurosis: 
 into the whole length of the ventral aspect of the vertebral border of 
 the scapula. Action, to elevate the ribs in inspiration, also to raise the 
 
 point of the shoulder. In Lhe lower animals it is the great sling-muscle, 
 slinging the body between the upper extremities. Nerve, posterior 
 thoracic. 
 
 MUSCLES OF THE SHOULDER AND ARM 
 
 Deltoid (8), from the outer third of the anterior and superior surfaces of 
 the clavicle, the outer margin and upper surface of the acromion, and the 
 lower border of the spine of the scapula: into a prominence on the outer 
 side of the shaft of the humerus, about its middle. Action, to raise the 
 arm. Nerve, circumflex (n. axillaris). 
 
 Subscapularis (15), from the inner two-thirds of the subscapular fossa: 
 into the lesser tuberosity of the humerus. Action, to rotate the head of 
 the humerus inward. Nerves, subscapular. 
 
MUSCLES OF THE UPPER EXTREMITY 
 
 101 
 
 Supraspinatus, from the inner two-thirds of the supraspinous fossa and 
 
 the fascia covering the muscle: into the upper facet of the greater tuber- 
 
 osity of the humerus. Action, to support the shoulder- joint, and to 
 
 raise the arm. Nerve, suprascapular. 
 Infraspinatus, from the inner two-thirds of the infraspinous fossa and the 
 
 covering fascia: into the middle facet on the greater tuberosity of the 
 
 humerus. Action, to rotate the humerus out- 
 ward. Nerve, suprascapular. 
 Teres Minor (14), from the upper two-thirds of 
 
 the dorsal surface of the axillary border of the 
 
 scapula: into the lowest facet on the greater 
 
 tuberosity of the humerus, and the bone below. 
 
 Action, to rotate the humerus outward. Nerve, 
 
 circumflex (n. axillaris). 
 
 Teres Major, from the dorsal aspect of the in- 
 ferior angle of the scapula: into the internal 
 
 bicipital ridge (crest of the small tubercle) 
 
 of the humerus. Action, to assist the latissimus 
 
 dorsi. Nerve, subscapular. 
 Coraco-brachialis (n), from the apex of the 
 
 coracoid process (2) of the scapula: into a ridge 
 
 on the inner side of the shaft of the humerus, 
 
 about its middle. Action, elevates the humerus 
 
 forward and inward. Nerve, musculo-cuta- 
 
 neous, which perforates this muscle. 
 Biceps (15) (biceps flexor cubiti), Long head (8) 
 
 from the upper margin of the glenoid cavity; 
 
 short head (12) from the apex of the coracoid 
 
 process (2), in common with the coraco-bra- 
 
 chialis : into the back of the tuberosity of the 
 
 radius, and the fascia (20) of the forearm. 
 
 Action, to flex and supinate the forearm, and 
 
 to make tense its fascia. Nerve, the musculo- 
 
 cutaneous. 
 Brachialis Anti'cus (m. brachialis) (17), from 
 
 the lower half of the shaft of the humerus an- 
 teriorly and laterally, embracing the insertion of the deltoid (9) : into 
 
 the base of the coronoid process (19) of the ulna. Action, a flexor of 
 
 the forearm. Nerves, musculo-cutaneous and musculo-spiral (n. 
 
 radialis). 
 
IO2 HUMAN ANATOMY 
 
 Triceps (16) (triceps extensor cubiti), by three heads, the outer (lateral) 
 and inner (medial) from the posterior surface of the shaft of the humerus, 
 the outer above, the inner below the musculo-spiral (radial) groove; 
 the middle or long head from a depression (infra-glenoid tuberosity) 
 below the glenoid cavity of the scapula; by a common tendon into the 
 upper end of the olecranon process of the ulna. Action, to extend the 
 forearm. Nerve, musculo-spiral (n. radialis). 
 
 Sub-anconeus, from the humerus above the olecranon fossa: into the 
 posterior ligament of the elbow- joint. Action, probably a tensor of the 
 ligament. Nerve, musculo-spiral (n. radialis). 
 
 MUSCLES OF THE FOREARM 
 
 Muscles of the Forearm, arranged in groups of 5 and 3. (Pancoast.) 
 ANTERIORLY, 5 flexors, 2 pronators, i tensor of palmar fascia: 
 
 Flexor Carpi Radialis. . j Pronator Radii Teres (m. pronator 
 Flexor Carpi Ulnaris. \ Pronator Quadralus. teres). 
 
 Flexor Longus Pollicis. Palmaris Longus. 
 
 f Flexor Sublimis Digitorum. 
 1 Flexor Profundus Digitorum. 
 
 POSTERIORLY 12 muscles in 4 sets of threes: 
 
 Brachio-radialis (Supinator Longus). Extensor Indicts. 
 Extensor Carpi Radialis Longior. Extensor Communis Digitorum. 
 Extensor Carpi Radialis Brevior. Extensor Minimi Digiti. 
 Extensor Ossis Metacarpi Pollicis. Extensor Carpi Ulnaris. 
 Extensor Brevis Pollicis. Anconeus. 
 
 Extensor Longus Pollicis. Supinator Brevis. 
 
 Pronator Radii Teres (m. pronator teres) (4), by 2 heads, one from above 
 the medial or internal condyle of the humerus, the common tendon, fas- 
 cia, and the intermuscular septum; the other from the medial or inner 
 side of the coronoid process of the ulna: into a rough ridge on the radial 
 or outer side of the shaft of the radius, about its middle. Action, to 
 pronate the hand. Nerve, median, which passes between the 2 heads 
 of the muscle. 
 
 Flexor Carpi Radialis (5), from the medial or internal condyle of the 
 
 humerus by "the common tendon, the fascia, and the intermuscular 
 
 septa: into the base of the metacarpal bone of the index finger. Action, 
 
 to flex the wrist. Nerve, median. 
 
 Palmaris Longus (6), from the same origin as the flexor carpi radialis: 
 
MUSCLES OF THE FOREARM 
 
 103 
 
 FIG. S3- 
 
 into the annular ligament (1. carpi transversum) and the palmar fascia 
 (9). Action, to make the palmar fascia tense. Nerve, median. 
 
 Flexor Carpi Ulnaris (8), by 2 heads, one from the inner or medial con- 
 dyle of the humerus by the common tendon, the other from the inner 
 or medial margin of the olecranon, the upper two-thirds of the posterior 
 border of the ulna, and the intermuscular septum: into the pisiform 
 bone, the annular ligament (1. carpi transver- 
 sum), and the 5th metacarpal and unciform 
 (hamate) bones. Action, to flex the wrist. 
 Nerve, ulnar. 
 
 Flexor Sublimis Digitorum (Perforatus) (7), by 
 3 heads, one from the medial or inner condyle 
 of the humerus by the common tendon, the 
 internal lateral or ulnar collateral ligament, and 
 the intermuscular septum; the second from the 
 inner side of the coronoid process of the ulna; 
 the third from the oblique line of the radius: 
 into the lateral margins of the second phalanges 
 by 4 tendons which are split for the passage of 
 the deep flexor tendons. Action, to flex the 
 second phalanges. Nerve, median. 
 
 Flexor Profundus Digitorum (Perforans), -from 
 the upper three-fourths of the shaft of the ulna, 
 a depression on the inner side of the coronoid 
 process, and the interosseous membrane: into 
 the bases of the last phalanges, by 4 tendons 
 which perforate the tendons of the superficial 
 flexor. Action, to flex the phalanges. Nerves, 
 ulnar, anterior interosseous branch of the 
 median. 
 
 Flexor Longus Pollicis, from the upper two- 
 thirds of the shaft of the radius and the in- 
 terosseous membrane: into the base of the last 
 
 phalanx of the thumb, which it flexes. Nerve, anterior interosseous 
 branch of the median. 
 
 Pronator Quadratus, from the oblique line on the lower fourth of the 
 ulna, and the anterior border of the ulna: into the lower fourth of the 
 anterior border of the shaft of the radius. Action, to pronate the hand. 
 Nerve, anterior interosseous branch of the median. 
 
104 HUMAN ANATOMY 
 
 Brachio-radialis or Supinator Longus (13), from the upper two-thirds of 
 the lateral or external condylar ridge of the humerus, and the inter- 
 muscular septum; into the base of the styloid process of the radius. 
 Action, to supinate the hand. Nerve, musculo-spiral (n. radialis). 
 
 Extensor Carpi Radialis Longior (e),from the lower third of the lateral or 
 external condylar ridge of the humerus, and the intermuscular septum: 
 into the base of the metacarpal bone of the index 
 FlG - 54- finger (g), on its radial side. Action, to extend 
 
 the wrist. Nerve, musculo-spiral (n. radialis). 
 
 Extensor Carpi Radialis Brevier (f),from the 
 lateral or external condyle of the humerus by 
 the common tendon, the external lateral liga- 
 ment, and the intermuscular septa: into the 
 radial side of the base of the 3d metacarpal 
 bone (g). Action, to extend the wrist. Nerve, 
 posterior interosseous. 
 
 Extensor Communis Digitorum (h),from the 
 lateral or external condyle of the humerus by 
 the common tendon, the deep fascia, and the 
 intermuscular septa: into the 2d and 3d 
 phalanges of all the fingers, by 3 tendons, one 
 of which divides into two. Action, to extend 
 the fingers. Nerve, posterior interosseous. 
 
 Extensor Minimi Digiti (m. extensor digiti quinti 
 proprius) (i),from the common tendon and 
 the intermuscular septa: into the 2d and 3d 
 phalanges of the little finger, with the tendon 
 derived from the common extensor. Action, as 
 named. Nerve, posterior interosseous. 
 
 Extensor Carpi Ulnaris (j),from the common 
 tendon, the middle third of the posterior border 
 of the ulna, and the deep fascia of the forearm: 
 into the base of the 5th metacarpal bone. Action, 
 to extend the wrist. Nerve, posterior interosseous. 
 
 Anconeus (), from the lateral or external condyle of the humerus, pos- 
 teriorly: into the side of the olecranon, and upper fourth of the posterior 
 surface of the shaft of the ulna. Action, to extend the forearm. Nerve, 
 the musculo-spiral (n. radialis). 
 
MUSCLES OF THE HAND 105 
 
 Supinator Brevis (m. supinator) from the external condyle of the hu- 
 merus, the external lateral and orbicular ligaments and an oblique line on 
 the ulna: into the inner surface of the neck of the radius, the outer edge 
 of its bicipital tuberosity, and the oblique line. Action, to supinate the 
 hand. Nerve, posterior interosseous, which pierces it. 
 
 Extensor Ossis Metacarpi Pollicis (m. abductor pollicis longus) (14), 
 from the posterior surfaces of the shafts of the radius and ulna, and the 
 interosseous membrane: into the base of the metacarpal bone of the 
 thumb. Action, to extend the thumb. Nerve, posterior interosseous. 
 
 Extensor Bievis Pollicis (Extensor Primi Internodii Pollicis) (n), from 
 the posterior surface of the shaft of the radius and the interosseous mem- 
 brane: into the base of the ist phalanx of the thumb. Action, to extend 
 the thumb. Nerve, posterior interosseous. 
 
 Extensor Longus Pollicis (Extensor Secundi Internodii Pollicis) (m), 
 from the shaft of the ulna posteriorly and the interosseous membrane: 
 into the base of the last phalanx of the thumb. Action, to extend the 
 thumb. Nerve, posterior interosseous. 
 
 Extensor Indicis (m. extensor indicis proprius) , from the shaft of the 
 ulna posteriorly and the interosseous membrane: into the 2d and 3d 
 phalanges of the index finger with the tendon of the common extensor. 
 Action, to extend the index finger. Nerve, posterior interosseous. 
 
 FASCIAE OF THE HAND 
 
 Anterior Annular Ligament (1. carpi transversum), from the pisi- 
 form and unciform (hamate) bones: to the tuberosity of the scaphoid 
 (navicular) and the ridge on the trapezium (great multangular). 
 Inserted into its anterior surface are parts of the tendons of the 
 palmaris longus and the flexor carpi radialis, and beneath it pass the 
 tendons of the superficial and deep flexors of the fingers and the 
 flexor longus pollicis, also the median nerve. It is continuous with 
 the palmar fascia and the deep fascia of the forearm. 
 
 Posterior Annular Ligament (1. carpi dorsale) (o),from the ulna, cunei- 
 form and pisiform bones: to the margin of the radius and the ridges on 
 its posterior surface. It has 6 canals for the passage of the extensor 
 tendons, each lined by a synovial membrane. It is continuous with the 
 deep fascia of the forearm. 
 
 Deep Palmar Fascia, ensheaths the muscles of the hand, and divides 
 into 4 slips for the four fingers, each slip dividing and forming tendinous 
 arches for the passage of the flexor tendons of the fingers. 
 
106 HUMAN ANATOMY 
 
 MUSCLES OF THE HAND 
 
 Abductor Pollicis (m. abductor pollicis brevis) (n), from the ridge of the 
 trapezium (great multangular) the tuberosity of the scaphoid (navicu- 
 lar) and the annular ligament (1. carpi transversum) : into the radial 
 side of the base of the ist phalanx of the thumb. Action, to draw the 
 thumb from the median line. Nerve, median. 
 
 Opponens Pollicis, from the palmar surface of the trapezium (great mult- 
 angular) and the annular ligament (1. carpi transversum): into the radial 
 side of the metacarpal bone of the thumb, for its whole length. Action, 
 as a flexor ossis metacarpi pollicis. Nerve, median. 
 
 Flexor Brevis Pollicis (12), the outer portion from the lower border of the 
 annular ligament (1. carpi transversum), the inner and deeper portion 
 from the ulnar side of the ist metacarpal bone: into both sides of the 
 base of the ist phalanx of the thumb, by two tendons, each having a 
 sesamoid bone in it. Action, to flex the thumb. Nerves, median and 
 ulnar. 
 
 Adductor Obliquus Pollicis (m. adductor pollicis), from the os magnum, 
 the bases of the 2d and 3d metacarpal bones, the anterior carpal liga- 
 ments and the sheath of the tendon of the flexor carpi radialis: into the 
 ulnar side of the base of the ist phalanx of the thumb, having a sesamoid 
 bone in the tendon of insertion. Action, to draw the thumb toward the 
 median line. Nerve, ulnar. 
 
 Adductor Transversus Pollicis,; from the lower two-thirds of the meta- 
 carpal bone of the middle finger: into the ulnar side of the base of the ist 
 phalanx of the thumb. Action, as the preceding muscle. Nerve, ulnar. 
 [The above-mentioned 5 muscles of the thumb occupy the radial side of 
 the hand and form the Thenar Eminence; the first 4 of the folio wing- men- 
 tioned muscles occupy the ulnar side of the hand and form the Hypothe- 
 nar Eminence.] 
 
 Palmaris Brevis (10), from the annular ligament and palmar fascia: into 
 the skin on the ulnar border of the palm of the hand. Action, to corru- 
 gate the skin of the hand. Nerve, ulnar. 
 
 Abductor Minimi Digiti (m. abductor digiti quinti), from the pisiform 
 bone and the tendon of the flexor carpi ulnaris: -into the ulnar side of 
 the base of the ist phalanx of the little finger and the aponeurosis of the 
 extensor minimi digiti. Action, as indicated by its name. Nerve, 
 ulnar. 
 
 Flexor Brevis Minimi Digiti (m. flexor digiti quinti brevis), from the 
 hook of the unciform bone and the annular ligament (1. carpi trans- 
 
MUSCLES OF THE LOWER EXTREMITY 1 07 
 
 versum) : into the base of the proximal phalanx of the little finger, with 
 the preceding muscle. Action, as named. Nerve, ulnar. 
 
 Opponens Minimi Digiti (m. opponens digiti quinti), from the unciform 
 or hamate bone and the annular ligament (1. carpi transversum) : into 
 the whole ulnar margin of the 5th metacarpal bone. Action, a flexor 
 of the 5th metacarpal bone. Nerve, ulnar. 
 
 Lumbricales 4, from the tendons of the deep flexor: into the expanded 
 tendons of the common extensor on the dorsi of the phalanges. Action, 
 to dorsiflex the proximal phalanges. Nerves, median and ulnar. These 
 muscles have no sheaths. 
 
 Dorsal Interossei 4, by 2 heads from the adjacent sides of the meta- 
 carpal bones: into the bases of the proximal phalanges of the index, 
 middle, and ring fingers, the middle finger having two. Action, abduc- 
 tors of the fingers from the median line of the hand. Nerve, ulnar. 
 
 Palmar Interossei (mm. interossei volares) 3, from the palmar surfaces 
 of the 2d, 4th, and 5th metacarpal bones: into the bases of the proximal 
 phalanges of the same fingers. Action, adductors of the fingers. Nerve, 
 ulnar. 
 
 MUSCLES OF THE LOWER EXTREMITY 
 
 MUSCLES AND FASCIAE OF THE ILIAC REGION 
 
 ILIAC FASCIA, is an aponeurotic layer which lines the back of the abdom- 
 inal cavity and covers the psoas and iliacus muscles throughout their 
 whole extent. It is attached above to the ligamentum arcuatum inter- 
 num (medial lumbo-costal arch), internally by arched processes to the 
 bodies of the vertebrae, also to the sacrum and the brim of the true pelvis; 
 externally it is continuous with the lumbar fascia above and is attached 
 to the whole length of the inner border of the crest of the ilium; below 
 it is continuous with the fascia transversalis and the pubic part of the 
 fascia lata of the thigh, is intimately connected to Poupart's (1. inguinale) 
 ligament, and is prolonged backward and inward therefrom as a band, 
 the Ilio-pectineal Ligament, to the ilio-pectineal eminence. It descends 
 behind the femoral vessels into the thigh, forming the posterior wall of 
 the femoral sheath. Transversalis Fascia lines the anterior abdominal 
 wall. 
 
 Psoas Magnus (m. psoas major) (n},from the bodies, transverse proc- 
 esses, and intervertebral substances of the last thoracic and all the 
 lumbar vertebrae: into the lesser trochanter of the femur, by a common 
 tendon with the iliacus. Action, to flex the thigh upon the pelvis, and 
 when the femur is fixed to bend the trunk forward. Nerves, anterior 
 branches of the 2nd and 3rd lumbar. 
 
108 HUMAN ANATOMY 
 
 Psoas Parvus (m. psoas minor), from the bodies of the last thoracic and 
 first lumbar vertebrae and the intervertebral substance: into the ilio- 
 pectineal eminence and the iliac fascia. Action, when present it is a 
 tensor of the iliac fascia. Nerve, anterior branch of the ist lumbar. 
 
 Iliacus (10), from the iliac fossa, inner margin of the iliac crest, ilio-lum- 
 bar ligament, base of the sacrum, anterior spinous processes of the ilium 
 and the notch between them: into the outer side of the tendon of the 
 psoas magnus, and the capsule of the hip- joint. Action, the same as 
 that of the psoas magnus. Nerve, anterior crural. 
 
 MUSCLES AND FASCIJE OF THE THIGH 
 
 SUPERFICIAL FASCIA, forms a continuous fatty covering over the whole 
 thigh, in which lie the superficial vessels and nerves. The superficial 
 layer is continuous above with Camper's fascia of the abdomen. The 
 deep fibrous layer (Scarpa's fascia) covers the saphenous opening in 
 the fascia lata (see below), where it is perforated for the internal 
 saphenous vein and numerous vessels, and is therefore called the Crib- 
 riform Fascia in this situation. It forms one of the coverings of 
 a femoral hernia. 
 
 FASCIA LATA, the deep fascia of the thigh, extends from Poupart's liga- 
 ment to the prominent points around the knee-joint, and from the mar- 
 gin of the sacrum and coccyx around the limb to the pubic arch and 
 pectineal line. It sends two strong intermuscular septa down to the 
 linea aspera, and contains the Saphenous Opening (fossa ovalis), which 
 is formed by the reflected margins of its pubic and iliac portions. The 
 structure named PouparCs Ligament (1. inguinale) is made by the knife, 
 and is only the line of junction between the aponeurosis of the external 
 oblique muscle and the fascia lata; extending from the anterior superior 
 spine of the ilium to the spine of the pubic bone. 
 
 Tensor Vaginae Femoris (m. tensor fasciae latae) (4), from the anterior 
 part of the outer lip of the iliac crest, the anterior superior spinous 
 process and part of the notch below it, also from the fascia covering 
 the gluteus medius: into the fascia lata, between its two layers, about 
 one-fourth down the outer side of the thigh. Action, a tensor of the 
 fascia lata. Nerve, superior gluteal. 
 
 Sartorius (5), -from the anterior superior spine of the ilium (2) and half of 
 the notch below it : into the upper internal surface of the shaft of the tibia. 
 Action, to flex and cross the legs. Nerve, anterior crural. 
 
 Quadriceps Extensor (m. quadriceps femoris), including the 4 remain- 
 ing muscles on the front of the thigh, the rectus femoris, vastus exter- 
 
MUSCLES OF THE THIGH 
 
 FIG. 55. 
 
 nus (m. vastus lateralis), vastus interims (m. vastus medialis), and the 
 
 crureus (m. vastus intermedius). Its tendon is inserted into the 
 
 patella. Action, the great extensor of the leg. Nerve, anterior crural. 
 Rectus Femoris (6), by two tendons, the Straight 
 
 from the anterior inferior spine of the ilium, the 
 
 Reflected from a groove above the brim of the 
 
 acetabulum: into the patella by a flattened 
 
 tendon (9) which is common to this and the 
 
 next 3 muscles. Action, to extend the leg. 
 
 Nerve, anterior crural (n. femoralis). 
 Vastus Externus (m. vastus lateralis) (7), from 
 
 the anterior border of the great trochanter and 
 
 part of the linea aspera of the femur: into the 
 
 outer border of the patella, by a flat tendon 
 
 which blends with the great extensor tendon. 
 
 Action, to extend the leg. Nerve, anterior 
 
 crural (n. femoralis). 
 Vastus Interims (m. vastus medialis) (8), from 
 
 the anterior intertrochanteric line, the spiral 
 
 line, the linea aspera, the internalsupracondylar 
 
 line, the tendon of the adductor magnus and the 
 
 intermuscular septum: into the inner border of 
 
 the patella and the great extensor tendon. 
 
 Action, to extend the leg. Nerve, anterior crural 
 
 (n. femoralis). 
 Crureus (m. vastus intermedius), from the upper 
 
 two-thirds of the shaft of the femur and the 
 
 intermuscular septum: into the great extensor 
 
 tendon. Action, to extend the leg. Nerve, an- 
 terior crural. This muscle and the vastus in- 
 
 ternus appear to be inseparably united, but 
 
 they can be separated. 
 Subcrureus (m. articularis genu), often blended with the crureus : from 
 
 the lower part of the shaft of the femur anteriorly; into the capsular 
 
 ligament behind the patella. Action, to draw up the capsular ligament. 
 
 Nerve, anterior crural. 
 Oracilis (15), from the margin of the symphysis and the anterior half of 
 
 the pubic arch: into the inner surface of the shaft of the tibia below the 
 
 tuberosity ( medial condyle). Action, to flex theleg and rotate it in ward, 
 
 also to adduct the thigh. Nerve, obturator. 
 
no 
 
 HUMAN ANATOMY 
 
 FIG. 56. 
 
 Pectineus (12), -from the ilio-pectineal line, and the bone in front thereof, 
 also from the fascia covering the muscle: into the rough line extending 
 from the trochanter minor to the linea aspera. Action, to adduct the 
 thigh and rotate it outward. Nerves, accessory obturator, anterior 
 crural (n. femoralis). 
 
 Adductor Longus (13), from the front of the os pubis: into the middle 
 third of the linea aspera. Action, to adduct the thigh powerfully. 
 Nerve, obturator. 
 
 Adductor Brevis, from the body and descending ramus of the os pubis; 
 into the upper part of the linea aspera. Action, 
 to adduct the thigh. Nerve, obturator. 
 Adductor Magnus (14), from the descending 
 ramus of the os pubis, the ramus of the ischium, 
 and the outer margin and under surface of the 
 tuberosity of the ischium: into the rough line 
 leading from the great trochanter to the linea 
 aspera, the whole length of the linea aspera, and 
 by a tendon into the tubercle on the inner 
 condyle of the femur. Action, to adduct the 
 thigh and rotate it outward. Nerves, obturator 
 and great sciatic. This muscle is pierced by 4 
 apertures for the 3 superior perforating and the 
 prof unda arteries, and about the lower one-third 
 of its insertion an angular interval is left 
 therein, the lower opening of Hunter's canal 
 (femoral canal), for the passage of the femoral 
 vessels into the popliteal space. 
 
 MUSCLES OF THE HIP 
 
 Gluteus Maximus (m. glutseus maximus) (b), 
 from the posterior gluteal line of the ilium, the 
 crest behind it, the last piece of the sacrum, the 
 side of the coccyx, the great sacro-sciatic liga- 
 ment, the aponeurosis of the erector spinae and 
 the fascia covering the gluteus medius : into the 
 fascia lata and the rough line leading from the 
 great trochanter to the linea aspera. Action, to extend and abduct the 
 thigh and rotate it outward, also to maintain the trunk erect. Nerves, 
 inferior gluteal from the sacral plexus. 
 Gluteus Medius (m. glutaeus medius) (a}, from the ilium between the 
 
MUSCLES OF THE HIP 
 
 III 
 
 posterior gluteal and the anterior gluteal lines, the crest between them, 
 and the fascia of the part: into the oblique lines on the great trochanter. 
 Action, its posterior fibres rotate the thigh outward, its anterior fibres 
 rotate inward. It also abducts the thigh and draws it forward, and 
 assists to maintain the trunk erect. Nerve, superior gluteal. 
 
 Gluteus Minimus (m. glutaeus minimus) (8) from the ilium between the 
 anterior and inferior gluteal lines, and the margin of the great sacro- 
 sciatic notch: into the anterior border of the great trochanter. Action, 
 to rotate the thigh inward, also to abduct and draw it forward, and to 
 maintain the trunk erect. Nerve, superior gluteal. 
 
 Pyriformis (9), by 3 digitations from the front of the sacrum, from the 
 margin of the great sacro-sciatic foramen and the great sacro-sciatic 
 ligament (1. sacro-tuberosum) : into the upper border of the great tro- 
 chanter (7), having passed through the great sacro-sciatic foramen. 
 Action, an external rotator of the 
 
 thigh. Nerves, first and second FIG. 57. 
 
 sacral. 
 
 Obturator Interims (n), from the 
 posterior bony margin of the ob- 
 turator foramen and the inner sur- 
 face of the obturator membrane: into 
 the great trochanter (7), passing 
 through the lesser sacro-sciatic fora- 
 men. Action, an external rotator of 
 the thigh. Nerve, a special nerve 
 from sacral plexus to the obturator 
 internus. 
 
 Gemellus Superior (io),from the outer 
 surface of the spine of the ischium: 
 into the great trochanter, being 
 blended with the tendon of the ob- 
 turator internus. Action, an ex- 
 ternal rotator of the thigh. Nerve, 
 the special nerve to the obturator 
 internus from the sacral plexus. 
 
 Gemellus Inferior (12), from the tuberosity of the ischium: into the 
 tendon of the obturator internus and the great trochanter. Action, 
 an external rotator of the thigh. Nerve, the special nerve from the 
 sacral plexus to the quadratus femoris. 
 
112 HUMAN ANATOMY 
 
 Quadratus Femoris (13), from the tuberosity of the ischium: into the 
 upper part of the linea quadrata on the trochanter major posteriorly. 
 Action, an external rotator of the thigh. Nerves, a special branch of 
 the sacral plexus. 
 
 Obturator Externus, from the anterior inner bony margin of the ob- 
 turator foramen, and the inner two-thirds of the anterior surface of the 
 obturator membrane: into the trochanteric or digital fossa of the femur. 
 Action, an external rotator of the thigh. Nerve, obturator. 
 
 Biceps (m. biceps femoris) (16), by 2 heads, the Long Head (d) from the 
 tuberosity of the ischium posteriorly, the Short Head (e) from the outer 
 lip of the linea aspera, and the intermuscular septum: into the outer 
 side of the head of the fibula; its tendon embracing the external lateral 
 (fibular collateral) ligament of the knee-joint and forming the Outer 
 Hamstring, the tendons of the semi-tendinosus, semi-membranosus, 
 gracilis and sartorius forming the Inner Hamstring. Action, to flex 
 the leg and rotate it outward. Nerve, great sciatic. 
 
 Semi-tendinosus (f),from the tuberosity of the ischium by a tendon 
 (4) common to it and the long head of the biceps, and from the adjacent 
 aponeurosis: into the shaft of the tibia at its upper and inner surface, 
 its tendon curving around the inner tuberosity (medial condyle). 
 Action, to flex the leg upon the thigh. Nerve, great sciatic. 
 
 Semi-membranosus (g), from the tuberosity of the ischium above the 
 origin of the above-named two muscles: into the inner tuberosity (medial 
 condyle) of the tibia; its tendon of insertion giving off fibrous expan- 
 sions one to the outer condyle of the femur forming part of the pos- 
 terior ligament of the knee-joint, another to the fascia .covering the 
 popliteus muscle, and fibres to the internal lateral (tibial collateral) 
 ligament of the joint. Action, to flex the leg, and rotate it inward. 
 Nerve, great sciatic. 
 
 External Rotators of the Hip-joint are 13^, the 3 adductors, pyriformis, 
 2 obturators, 2 gemelli, quadratus femoris, pectineus, psoas magnus, 
 iliacus, sartorius, and posterior half of the gluteus medius. 
 
 Internal Rotators of the Hip-joint are 2^, the tensor vaginae femoris, 
 gluteus minimus, and the anterior half of the gluteus medius. 
 
 MUSCLES OF THE LEG 
 
 Tibialis Anti'cus (m. tibialis anterior) (3), -from the outer tuberosity 
 (lateral condyle) and upper two-thirds of the shaft of the tibia externally, 
 the interosseous membrane, deep fascia, and intermuscular septum; 
 through the inner canal in the anterior annular ligament (11. transversum 
 
MUSCLES OF THE LEG 
 
 PIG. 58. 
 
 et cruciatum cruris) : into the inner and plantar surface of the internal 
 cuneiform bone, and the base of the ist metatarsal. Action, to flex 
 the tarsus on the leg, and elevate the inner border of the foot. Nerve, 
 anterior tibial. 
 
 Extensor Proprius Hallucis (m. extensor hallucis longus) (5), from the 
 middle two-fourths of the fibula anteriorly and the interosseous mem- 
 brane, through the 2d canal in the anterior annular ligament: (1. trans- 
 versum cruris et 1. cruciatum cruris) : into the base of the terminal or 
 distal phalanx of the great toe. Action, to 
 extend that toe. Nerve, anterior tibial (deep 
 peroneal nerve). 
 
 Extensor Longus Digitorum (m. extensor digi- 
 torum longus) (4), from the outer tuberosity 
 (lateral condyle) of the tibia the upper three- 
 fourths of the extensor surface of the shaft of 
 the fibula anteriorly, interosseous membrane, 
 deep fascia, and intermuscular septa: into the 
 2d and 3d phalanges of the 4 lesser toes, by 4 
 tendons which pass over the dorsum of the 
 foot from the outer canal in the anterior an- 
 nular ligament (11. transversum et cruciatum 
 cruris). Action, to extend the lesser toes. 
 Nerve, anterior tibial (deep peroneal). 
 
 Peroneus Tertius (m. peronasus tertius) (6), 
 from the outer lower fourth of the extensor 
 surface of the fibula, interosseous membrane 
 and intermuscular septum: into the base of 
 the 5th metatarsal bone. This muscle is a 
 part of the last-named, and passes through the 
 same canal in the annular ligament (11. trans- 
 versum et cruciatum cruris). Action, to dorsi- 
 flex the tarsus. Nerve, anterior tibial (deep 
 peroneal). 
 
 Gastrocnemius, by 2 heads (9, 10), from the 
 condyles of the femur, and the supra-condylar 
 ridges: unites with the tendon of the soleus to form the tendo Achillis, 
 into the posterior tuberosity of the os calcis (calcaneus). Action, to 
 extend the foot or flex the calcaneus. Nerve, internal popliteal (n. 
 tibialis). 
 
 / Soleus, from the head and upper third of the flexor surface of the shaft 
 8 
 
HUMAN ANATOMY 
 
 FIG. 59. 
 
 of the fibula posteriorly, the oblique line of the tibia, and the tendinous 
 arch: unites with the tendon of the gastrocnemius as the tendo A chillis 
 (see above). Action, to extend the foot and flex the heel. Nerves, 
 internal popliteal, posterior tibial (nn. tibialis). 
 
 Plantaris, from the outer bifurcation of the linea aspera and the posterior 
 ligament of the knee-joint: by a very long, delicate tendon into the 
 posterior surface of the os calcis. Action, to extend the foot and flex the 
 heel. Nerve, internal popliteal (n. tibialis). 
 
 Popliteus (6 Fig. 59), from a depression on the external (lateral) condyle 
 of the femur, and the posterior ligament of the knee- 
 joint: into the inner two-thirds of the triangular surface 
 on the shaft of the tibia (2) posteriorly and above the 
 oblique line. Action, to flex the leg. Nerve, internal 
 > popliteal (n. tibialis). 
 
 Flexor Longus Hallucis (m. flexor hallucis longus) (9), 
 from the lower two-thirds of the flexor surface of the 
 shaft of the fibula, the interosseous membrane, fascia, 
 and intermuscular septum, its tendon passing through 
 grooves in the tibia, astragalus and os calcis: into the 
 base of the last phalanx of the great toe. Action, to 
 flex the great toe. Nerve, posterior tibial (n. tibialis). 
 Flexor Longus Digitorum (m. flexor digitorum longus) 
 (7) from the shaft of the tibia posteriorly and below 
 the oblique line; its tendon passing behind the inner 
 I? malleolus in a groove (13) with the tibialis posticus 
 
 (m. tibialis posterior): into the bases of the last 
 phalanges of the lesser toes by 4 tendons which per- 
 forate the tendons of the flexor brevis digitorum. 
 Action, to flex the phalanges and extend the foot. 
 I Nerve, posterior tibial (n. tibialis). 
 Tibialis Posti'cus (m. tibialis posterior) (8), by two 
 processes between which pass the anterior tibial ves- 
 sels, from the upper half of shaft of the tibia poste- 
 riorly, the upper two-thirds of the flexor surface of the 
 shaft of the fibula internally, the interosseous mem- 
 brane, deep fascia, and intermuscular septa; its ten- 
 don passes behind the inner malleolus in a groove (13) with the long 
 flexor: into the tuberosity of the scaphoid and internal cuneiform bones. 
 Action, to extend the tarsus and invert the foot. Nerve, posterior tibial 
 (n. tibialis). 
 
MUSCLES OF THE LEG 115 
 
 Peroneus Longus (m. peronaeus longus) (io),from the head of the fibula, 
 and the upper two-thirds of the peroneal surface of its shaft externally, 
 the deep fascia and intermuscular septa, passes behind the outer malleo- 
 lus in a groove with the peroneus brevis, through a groove in the cuboid 
 bone: into the outer side of the base of the metatarsal bone of the great 
 toe and the internal cuneiform bone, having crossed the sole of the foot 
 obliquely. Action, to extend and evert the foot and flex the heel. 
 Nerve, musculo-cutaneous branch of the external popliteal (n. peronaei 
 superficialis). 
 
 /Peroneus Brevis (m. peronaeus brevis) (n), from the middle third of the 
 peroneal surface of the shaft of the fibula externally and the inter- 
 muscular septa: its tendon passes behind the external malleolus in a 
 groove with the long peroneal, into the dorsum of the base of the 5th 
 metatarsal bone. Action, to extend the foot. Nerve, musculo-cutane- 
 ous branch of the external popliteal (n. peronaei superficialis). 
 
 FASCIA OF THE FOOT 
 
 ANTERIOR ANNULAR LIGAMENT (11. transversum et cruciatum cruris) 
 (12 Fig. 58), consists of vertical and horizontal portions, is attached 
 to the lower ends of the fibula and tibia, the os calcis and the plantar 
 fascia. It contains sheaths lined by synovial membranes for the ten- 
 dons of the extensor muscles (that of the extensor proprius hallucis 
 passing beneath it), as also the anterior tibial vessels and nerve. 
 
 INTERNAL ANNULAR LIGAMENT (1. laciniatum), from the inner malleolus 
 to the os calcis (calcaneus), converting 4 bony grooves into canals lined 
 by synovial membranes for the flexor tendons and the posterior tibial 
 vessels and nerves. 
 
 EXTERNAL ANNULAR LIGAMENT (1. peronaei retinaculum superior), front 
 the outer malleolus to the os calcis, binding down the peronei tendons 
 in one synovial sac. 
 
 i / PLANTAR FASCIA, the densest in the body, divided into a central and two 
 
 lateral portions, and attached to the inner tuberosity of the os calcis, 
 
 f divides into 5 processes, i for each toe, and several intermuscular septa. 
 
 ^ DORSAL FASCIA, is a thin membranous layer continuous above with the 
 
 anterior margin of the annular ligament, and becoming gradually lost 
 
 opposite the heads of the metatarsal bones, and on each side blending 
 
 with the plantar fascia. It forms a sheath for the tendons on the dorsum 
 
 of the foot. 
 
 MUSCLES or THE FOOT 
 
 Extensor Brevis Digitorum (m. extensor digitorum brevis) (n Fig. 58), 
 the only muscle on the dorsum of the foot, arises from the os calcis 
 
Il6 HUMAN ANATOMY 
 
 externally, the calcaneo-astragaloid and the anterior annular ligaments 
 (1. cruciatum cruris): by 4 tendons, i into the proximal phalanx of 
 the great toe, and the others into the outer sides of the long extensor 
 tendons of the 2d, 3d, and 4th toes. A ction, to extend the toes. Nerve, 
 anterior tibial (deep peroneal). 
 Muscles on the sole of the foot number 19; arranged by layers: 
 
 ist Layer 3d Layer 
 
 Abductor Hallucis. Flexor Brevis Hallucis (m. flexor hallu- 
 
 cis brevis). 
 
 Flexor Brevis Digitorum (m. Adductor Obliquus Hallucis (caput obli- 
 
 flexor digitorum brevis). quum m. adductoris hallucis). 
 
 Abductor Minimi Digiti (m. Flexcr Brevis Minimi Digiti (m. flexor 
 
 abductor digiti quinti). digiti quinti brevis). 
 
 2d Layer Adductor Transfer sus Hallucis (caput 
 
 Flexor Accessorius (m. quad- transversum m. adductoris hallucis). 
 
 ratus plantae). 4th Layer 
 
 Lumbricales, 4. Interossei (4 Dorsal, 3 Plantar). 
 
 Abductor Hallucis,*- from the inner tubercle of the os calcis (calcaneus), 
 the internal annular ligament (1. laciniatum), plantar fascia, and inter- 
 muscular septum: into the inner side of the base of the ist phalanx of 
 the great toe. Action, to abduct the great toe. Nerve, internal plantar 
 (n. plantaris medialis). 
 
 Flexor Brevis Digitorum (m. flexor digitorum brevis), from the inner 
 tubercle of the os calcis (calcaneus) (n), the plantar fascia and inter- 
 muscular septa: into the sides of the 2d phalanges of the lesser toes by 4 
 tendons (5) which are perforated for the long flexor tendons (2). Action, 
 to flex the lesser toes. Nerve, internal plantar (n. plantaris medialis). 
 
 Abductor Minimi Digiti (m. abductor digiti quinti), from the tubercles 
 and under surface of the os calcis (calcaneus) (n), the plantar fascia and 
 the intermuscular septum: into the base of the proximal phalanx of the 
 little toe with the tendon of its short flexor. Action, to abduct the little 
 toe. Nerve, external plantar (n. plantaris lateralis). 
 
 Flexor Accessorius (m. quadratus plantae) (i), by 2 heads, from the os 
 calcis (calcaneus) and the long plantar ligament : into the tendon of the 
 flexor longus digitorum. Action, accessory flexor of the toes. Nerve, 
 external plantar (n. plantaris lateralis). 
 
 Lumbricales (4), iour,from the long flexor tendons: each into the dorsum of 
 the proximal phalanx of the corresponding toe. Action, accessory 
 
MUSCLES OF THE FOOT 1 17 
 
 flexors of the toes and to dorsiflex the proximal phalanges. Nerves, in- 
 ternal plantar (n. plantaris medialis) to the innermost lumbrical, 
 external plantar (n. plantaris lateralis) to the other three. 
 
 Flexor Brevis Hallucis (m. flexor hallucis brevis) (7), -from the cuboid 
 
 and external cuneiform bones, and the prolonged tendon of the tibialis 
 
 posticus (m. tibialis posterior) : into both sides of the base of the proximal 
 
 phalanx of the great toe, by 2 portions, of which one blends with the 
 
 abductor hallucis, the other with the adductor ob- 
 
 liquus hallucis. Action, to flex the great toe. 
 
 Nerve, internal plantar (n. plantaris medialis). 
 Adductor Obliquus Hallucis (caput obliquum m. 
 
 adductoris hallucis), from the tarsal ends of 
 
 the three middle metatarsal bones, and the 
 
 sheath of the tendon of the peroneus longus: 
 
 into the base of the proximal phalanx of the 
 
 great toe, externally. Action, to adduct the 
 
 great toe. Nerve, external plantar (n. plantaris 
 
 lateralis) . 
 Flexor Brevis Minimi Digiti (m. flexor digiti quinti 
 
 brevis) (6), from the base of the 5th metatarsal 
 
 bone (9) and the sheath of the tendon of the pero- 
 neus longus: into the base of the proximal 
 
 phalanx of the little toe externally. Action, to 
 
 flex the little toe. Nerve, external plantar (n. 
 
 plantaris lateralis.) 
 Adductor Transversus Hallucis (caput transversum 
 
 m. adductoris hallucis) (Transversus Pedis), from 
 
 the inferior metatarso-phalangeal ligaments of 
 
 the three outer toes and the transverse ligament of the metatarsus: 
 
 into the outer side of the proximal phalanx of the great toe, blending with 
 
 the tendon of the adductor obliquus hallucis. Action, to adduct the 
 
 great toe. Nerve, external plantar (n. plantaris lateralis). 
 
 Dorsal Interossei (4), each by two heads from the adjacent sides of 
 two metatarsal bones: into the base of the proximal phalanx of the 
 corresponding toe. Action, to abduct the toes. Nerve, external plantar. 
 
 Plantar Interossei 3, from the shafts of the 3d, 4th, and 5th metatarsai 
 bones: into the bases of the proximal phalanges of the same toes. Ac- 
 tion, to adduct the toes toward the median line. Nerve, external plantar 
 (n. plantaris lateralis). 
 
Il8 HUMAN ANATOMY 
 
 THE BLOOD-VASCULAR SYSTEM 
 THE HEART OR COR 
 
 The Pericardium is a conical membranous sac, containing the heart and 
 the roots of the great vessels. It lies behind the sternum and between the 
 plurae, its apex upward, its base attached to the central tendon of the dia- 
 phragm. It is composed of an outer fibrous coat, and an inner serous one; 
 the former is prolonged on the outer surfaces of the great vessels, except 
 the inferior vena cava, and becomes continuous with the deep layer of the 
 cervical fascia; the latter consists of a parietal layer, lining the inner sur- 
 face of the fibrous coat, and a visceral layer, which is reflected over the 
 heart and vessels. The serous portion secretes a thin fluid, about i drachm 
 in quantity normally, for the lubrication of its surfaces. Arteries, are 
 derived from the internal mammary and its musculo-phrenic branch, and 
 from the descending thoracic aorta. Nerves, are branches from the vagus, 
 the phrenic and the sympathetic. 
 
 The Endocardium is a thin, smooth, transparent membrane, which lines 
 the internal surface of the heart; assisting by its reduplications in forming 
 the valves, and being continuous with the lining membrane of the great 
 blood-vessels. 
 
 JThe Heart (cor) is a hollow muscular organ, conoidal in shape, placed 
 obliquely in the chest between the lungs, base upward, apex to the left and 
 front, corresponding to the space between the 5th and 6th costal cartilages, 
 % inch inside of and i^ inch below the left nipple. In the adult its size 
 is about 5 inches by 3^ by 2%, and from 10 to 12 oz. in weight in the male, 
 8 to 10 oz. in the female. 
 
 The Cavities of the Heart are 4 in number, an atrium and ventricle on 
 each side of the heart; the cavities on one side being separated from those 
 of the other side by a longitudinal muscular septum. The division into 4 
 cavities is indicated on the external surface of the organ by grooves, named, 
 from their contiguous cavities, the auricula-ventricular groove transversely, 
 and the inter-ventricular grooves longitudinally. 
 
 Structure of the Heart. The muscular fibres forming the heart take 
 origin from four fibrous rings at the auriculo-ventricular and aortic open- 
 ings. The fibres of the auricles are arranged in two layers, a superficial 
 and a deep one, the latter having looped fibres and annular fibres. In the 
 ventricles the fibres are also superficial and deep, the latter being arranged 
 circularly, the former spirally, coiling inward at the apex of the heart into a 
 whorl-like form, the vortex. 
 
THE HEART 
 
 IIQ 
 
 FIG. 61. 
 
 Vessels and Nerves. The Arteries are the right and left coronary from 
 theTaorta. The Veins accompany the arteries and terminate in the right 
 auricle. The Lymphatics, terminate in the thoracic and right lymphatic 
 ducts. The N> / are derived from the cardiac plexuses, which are 
 formed partly f vhe cranial nerves and partly from the sympathetic. 
 
 THE RIGHT HEART 
 
 The Right Auricle (atrium dextrum) is slightly larger than the left, its 
 walls somewhat thinner, being about one line in thickness; its cavity con- 
 tains about 2 fluidounces. It consists of two parts, a principal cavity, the 
 sinus venosus (i) or atrium, 
 situated posteriorly, and a 
 smaller portion, the appendix 
 auricula (auricula dextra) (2), 
 situated anteriorly. It re- 
 ceives the venous blood by 
 the superior (3) and inferior 
 (4) venae cavae and the coro- 
 nary sinus, and presents in- 
 teriorly the following points 
 for examination: 
 
 Appendix Auricula (auric- 
 ula dextra) (n), a con- 
 ical pouch projecting from 
 the sinus to the front and 
 left, its margins being 
 dentq,ted. 
 Openings of the superior 
 
 and inferior venae cavae and the coronary sinus (7), the latter having 
 a valve in two segments. 
 foramina Thebesii (foramina venarum minimarum), several minute 
 
 orifices, the mouths of veins from the substance of the heart. 
 Auricula-ventricular Opening (ostium venosum dextrum) (9), com- 
 municates with the right ventricle, is oval, about i% inch broad, 
 surrounded by a fibrous ring, and is guarded by the tricuspid valve. 
 Fossa Ovalis (5), a depression on the inner wall, corresponding to the 
 
 situation of the foramen ovale in the foetus. 
 Annulus Ovalis (limbus fossae ovalis [Vieussenii]), the oval margin of 
 
 the fossa ovalis. 
 
 Musculi Pectinatij muscular columns on the inner surface of the appen- 
 dix and the inner wall of the auricle. 
 
120 HUMAN ANATOMY 
 
 Tubercle of Lower (tuberculum intervenosum [Lower!]), a very small 
 projection on the right wall, supposed to influence the direction of the 
 blood-current. 
 
 Eustachian Valve (valvula venae cavae inferioris [Eustachii]) (6), at 
 the anterior margin of the inferior vena cava; large in the foetus, to 
 direct the blood to the foramen ovale. 
 
 Coronary Valve (valvulae sinus coronarii [Thebesii]) (Valve of Thebe- 
 sius) (8), a semicircular fold which protects the orifice of the 
 coronary sinus and prevents regurgitation of blood into the sinus. 
 
 The Right Ventricle (ventriculus dexter) (a) is triangular in form and 
 extends from the right auricle to near the apex of the heart. Its anterior 
 surface is rounded and convex and forms the larger part of the front of 
 the heart. Its under surface is flattened and rests upon the diaphragm. 
 Its cavity (b c) can contain about 3 fluidounces, and presents the following 
 points for examination: 
 
 Tricuspid Valve (valvula tricuspidalis) (e, /), consists of 3 triangular 
 segments connected by their bases with the auriculo-ventricular ori- 
 fice, and by their sides with each other, the largest being on the left 
 side. 
 
 Semilunar Valves (valvulse semilunares a. pulmonalis) (m), are 3 in 
 number, and guard the orifice of the pulmonary artery; each about 
 the middle of its free margin has a fibrocartilaginous nodule, the 
 corpus Arantii (noduli valvarum semilunarum [Arantii]), which 
 more perfectly closes the orifice. 
 
 Opening of the Pulmonary Artery (ostium arteriosum pulmonis), at the 
 superior and internal angle of the ventricle, the conus artericsus. It 
 is circular in form, surrounded by a fibrous ring, and is guarded by 
 three semilunar valves. 
 
 Sinuses of Valsalva, are 3 pouches, one behind each valve, between it 
 and the commencement of the pulmonary artery. 
 
 Columns Ccrnece, (trabeculae carnae) (g), muscular columns projecting 
 from the surface of the ventricle, of which 3 or 4, called musculi 
 papillares, give attachment to the chordae tendinae. 
 
 Chorda Tending (1), delicate tendinous cords which connect the mar- 
 gins and lower surfaces of the tricuspid valve with the columnae. 
 
 THE LEFT HEART 
 
 The Left Auricle (atrium sinistrum) is smaller than the right, but has 
 thicker walls, being about i^ line. Like the right auricle it consists of a 
 principal cavity (i) or sinus (atrium) and an appendix auricula (auricula 
 
THE HEART 
 
 121 
 
 sinistra, (2), which overlaps the root of the pulmonary artery. Internally 
 the auricle presents the following parts: 
 
 Openings (3) of the Pulmonary Veins, are 4 in number, sometimes 3, as 
 the two left veins (5) frequently end in a common opening. They 
 have no valves. 
 Left Auricula-ventricular Opening (ostium venosum ventriculi sinistri) 
 
 (6), is smaller than the right one. 
 
 Musculi Peciinati, on the inner surface of the appendix. 
 Depression, corresponding to the fossa ovalis in the right auricle. 
 
 FIG. 62. 
 
 The Left Ventricle (ventriculus sin- 
 ister) (8) is longer, thicker and more 
 conical in shape than the right ven- 
 tricle (/O, and it forms a small part of V- 
 the anterior surface of the heart but 
 a considerable part of its posterior 
 surface. By its projection beyond 
 the apex of the right ventricle it 
 forms the apex of the heart. Its walls 
 are the thickest of those in the heart, 
 being thrice as thick as those of the 
 right ventricle. Its interior (9) pre- 
 sents the following: 
 
 Left Auricula-ventricular Opening 
 (ostium venosum ventriculi sin- 
 istri), is surrounded by a dense 
 fibrous ring (annulus fibrosus sin- 
 ister) and is guarded by the mitral 
 valve (valvula bicuspidalis). 
 Aortic Opening (ostium arteriosum), is small and circular, placed in 
 front and to the right of the auriculo-ventricular, a segment of the 
 mitral (bicuspid) valve being between them. It is surrounded by a 
 fibrous ring, and guarded by the semilunar valves (valvulae semi- 
 lunares aortae). 
 
 Mitral Valve (valvula bicuspidalis) (a), consists of two unequal- 
 sized segments, and is attached to the fibrous ring which surrounds 
 the auriculo-ventricular opening (ostium venosum ventriculi sinistri). 
 Its margins are connected with the ventricular walls by chordae 
 tendinae and musculi papillares. 
 
 Semilunar Valves (valvulae semilunares aortae), 3 in number ggjuard the 
 aortic orifice, and are larger and stronger than those on the right side. 
 
122 HUMAN ANATOMY 
 
 Sinus of Valsalva, a pouch in the wall of the aorta opposite each seg- 
 ment of the semilunar valves. 
 
 ColumncB Carnea (6), are smaller and more numerous than those on 
 the right side; the musculi papillares are but two in number, one con- 
 nected to the anterior, the other to the posterior wall. 
 
 THE ARTERIES 
 
 The Arteries are cylindrical tubular vessels which carry blood from the 
 ventricles of the heart to every part of the body. The Aorta and its 
 branches, together with the returning veins, constitute the greater or 
 systemic circulation. The Pulmonary Artery and its branches to the lungs, 
 together with the returning veins, constitute the lesser or pulmonic cir- 
 culation. The arteries anastomose or communicate freely with each 
 other everywhere throughout the body, permitting the establishment of 
 collateral circulations. 
 
 Structure of the Arteries. They are dense in structure, very elastic, 
 preserving their cylindrical form, and are composed of 3 coats, an Internal 
 or serous (tunica intima); a Middle (tunica media), composed of muscular 
 and elastic tissue; and an External (tunica externa or adventitia), com- 
 posed of connective tissue. They are generally included in a fibro- 
 areolar investment, the Sheath, which also encloses the accompanying veins. 
 The larger arteries are nourished by the Vasa Vasorum, blood-vessels 
 which ramify in the external and middle coats; and are supplied with 
 nerves, the Vaso-motor, derived from both the sympathetic and cerebro- 
 spinal systems, and forming intricate plexuses on the larger trunks. 
 
 The Capillaries are minute vessels forming a network throughout the 
 tissues of the body between the terminating arteries and the commencing 
 veins. Their average diameter is about the Hooo of an inch, average 
 length ^o of an inch and their walls consist of a transparent homoge- 
 neous membrane continuous with the innermost layer of the arterial 
 and venous walls. 
 
 THE PULMONARY ARTERY AND AORTA 
 
 The Pulmonary Artery (a. pulmonalis) alone of the arteries carries 
 venous blood, which it conveys from the right side of the heart to the 
 lungs. It is i^-i inch in diameter and only about 2 inches long, and all 
 within the pericardium; arising from the right ventricle in front of the 
 ascending aorta, passing upward and backward to the under surface of 
 the arch of the aorta, where it bifurcates, and is connected at its root to 
 
THE AORTA 123 
 
 the aorta by a fibrous cord, the remains of the ductus artcriosus of the 
 foetus. Its terminal branches are the 
 
 Right (ramus dexter a. pulmonalis) and Left (ramus sinister a. pulmonalis) 
 Pulmonary Arteries, the latter being tne" shorter of the two; they pass 
 horizontally outward to the roots of their respective lungs, where each 
 divides into two branches, which again and again subdivide to ramify 
 throughout the lung tissue and end in the capillaries of those organs. 
 
 The Aorta (arteria magna) is the main trunk of the systemic arteries, 
 commencing at the aortic opening of the left ventricle of the heart, it arches 
 backward over the roof of the left lung into the thorax, where it descends 
 on the left of the spinal column, and after passing through the aortic 
 opening in the diaphragm, it terminates in the right and left common 
 iliac arteries opposite the 4th lumbar vertebra. It is divided into the 
 ^Ascending Aorta (aorta asc'ehdens) (5), the Arch (arcus aortae) (6), and 
 the Ascending Aorta (aorta descendens) (12), the last-named being again 
 divided into the Thoracic Aorta (aorta thoracalis) and the Abdominal 
 Aorta (aorta abddnimalis) (described under Arteries of the Trunk). 
 Th*e" upper border of the arch is generally situated about an inch below 
 the upper margin of the sternum. The branches of the aorta are 
 
 From the Ascending Aorta, 2 Coronary Arteries (4). 
 
 From the Arch, Innominate (a. anonyma) (7). Left Common Carotid 
 
 (10). Left Subclavian (n). 
 From the Thoracic, Pericardia!. (Esophageal. 18 Intercostals. 
 
 Bronchial. Posterior Mediastinal. 
 
 From the Abdominal, 2 Phrenic. 
 
 { Gastric. 
 Cceliac Axis. { Hepatic. 
 
 ( Splenic (a. lienalis). 
 
 2 Spermatic, in the male. 
 
 2 Ovarian, in female. Inferior Mesenteric. 
 
 Superior Mesenteric. 8 Lumbar. 
 
 2 Supra-renal. Sacra Media. 
 
 2 Renal. 2 Common Iliac. 
 
 The Coronary Arteries are 2 in number, a right and a left (4), arise from 
 the aorta in the sinuses of Valsalva behind the semilunar valves, and run in 
 the vertical grooves of the heart, the left artery in front, to supply the 
 tissue of that organ. Each artery divides into 2 branches, the transverse 
 and the descending, the latter anastomosing at the apex of the heart with 
 its fellow of the opposite side. The descending branch of the right coro- 
 
124 
 
 HUMAN ANATOMY 
 
 FIG. 63. 
 
 nary sends off a marginal branch along the margin of the right ventricle, 
 and an infundibular branch to the conus ar- 
 teriosus of the same ventricle. 
 
 The Innominate Artery (a. anonyma) (7) 
 arises from the summit of the arch of the 
 aorta, is i^ inch long, and divides behind 
 the right sternoclavicular joint into the Right 
 Common Carotid (9) and Right Subdavian (8), 
 these arteries on the left side of the body (10, 
 n) arising directly from the arch of the aorta. 
 It sometimes sends off a small branch, the 
 Thyroidea ima, to the thyroid body; which 
 vessel may arise from the arch of the aorta, 
 the right common carotid, the subclavian, or 
 the internal mammary. The Innominate 
 artery is sometimes absent and not infre- 
 quently varies in length from }$ inch to 2 inches. 
 
 ARTERIES OF THE HEAD AND NECK 
 
 The Common Carotid Arteries 
 
 (Arterae Carotides Communes). 
 Arising differently (see above) 
 the two carotids are similarly 
 described, except that the left 
 is longer and deeper than the 
 right one. Their course is indi- 
 cated by a line drawn from a 
 point midway between the 
 angle of the lower jaw and the 
 mastoid process to the sterno- 
 clavicular articulation. At the 
 lower part of the neck they are 
 separated only by the width of 
 the trachea, and they are each 
 contained in a sheath of the 
 deep cervical fascia with the 
 internal jugular vein externally 
 and the pneumogastric nerve 
 (n. vagus) between the artery 
 and vein. On the front of the 
 sheath lies the descendens hypo- 
 
 Pic. 64. 
 
ARTERIES OF THE HEAD AND NECK 125 
 
 glossi nerve (descending branch of the i2th or hypoglossal). The 
 artery lies beneath the inner border of the sterno-cleido-mastoid muscle, 
 and is crossed about its middle by the omo-hyoid muscle and the middle 
 thyroid vein. It is also crossed above by the facial, lingual, and su- 
 perior thyroid veins, below by the anterior jugular vein, and on the left 
 side often by the internal jugular vein. It bifurcates, at the level of the 
 upper border of the thyroid cartilage, into the External and Internal 
 Carotids, of which the internal is the more remote from the median line. 
 
 The External Carotid Artery (a. carotis externa) (2) (Fig. 64) commences 
 opposite the upper border of the thyroid cartilage, and passes upward, 
 forward and backward to the space between the neck of the condyle of the 
 lower jaw and the external meat us, where it divides into the temporal and 
 internal maxillary arteries. It has 8 branches, the 
 Superior Thyroid (a. thyreoidea superior) (4), arising below the greater 
 
 cornu of the hyoid bone; giving off 
 
 Muscular. Hyoid. Superior Laryngeal. 
 
 Glandular. Superficial Descending. Crico-thyroid. 
 
 Lingual (a. lingualis) (5), under the hyo-glossus muscle to the tongue; 
 
 giving off 
 
 Hyoid. Dorsalis Linguae. Sublingual. Ranine. 
 Facial (a. maxillaris externa), should be called superficial facial (6), 
 
 crosses the lower jaw at the anterior border of the masseter; giving 
 
 off- 
 Inferior (Ascending) Palatine. Submental (7). 2 Coronary (aa. la- 
 
 Tonsillar. Muscular. biales) (8, 9). 
 
 Submandibular. Inferior Labial. Lateralis Nasi. 
 
 Angular. 
 
 Occipital (a. occipitalis) (10), lies in the occipital groove of the temporal 
 bone. 
 
 Muscular. Auricular. Arteria Princeps Cervicis 
 
 Sterno-mastoid. Meningeal. (13) (ramus descen- 
 
 dens a. occipitalis). 
 
 Posterior Auricular (a. auricularis posterior) (14), ascends under cover of 
 
 the parotid gland. 
 
 Stylo-mastoid. Auricular. Mastoid. Muscular. Glandular. 
 Ascending Pharyngeal, (a. pharyngea ascendens), lies on the rectus 
 capitis anticus major. 
 
 Prevertebral. Pharyngeal. Tympanic. Meningeal. 
 
126 
 
 HUMAN ANATOMY 
 
 FIG. 65. 
 
 Superficial Temporal (a. temporalis superficialis) (15), the smallest of the 
 termini of the external carotid, begins in the parotid gland, crosses the 
 zygomatic arch, and divides into anterior (13) and posterior temporal 
 (16). Its branches are the 
 
 Parotid. Articular. Zygomatico-orbital. Frontal. Parietal. 
 Transverse Facial (15). Middle Temporal (17). Anterior Auricular. 
 
 Internal Maxillary (a. maxillaris in- 
 terna), should be called deep facial 
 (4), the other terminal branch 
 of the external carotid (i), is di- 
 vided into three portions, Maxil- 
 lary (4), Pterygoid (5), and 
 Spheno- maxillary (6), which re- 
 spectively give off the following 
 branches (Fig. 65): 
 
 Maxillary 
 
 Deep Auricular, to the tragus 
 
 and canal. 
 
 Anterior Tympanic (7), enter- 
 ing the Glaserian (petro-tym- 
 panic) fissure. 
 Middle Meningeal (8). 
 Small or Accessory Meningeal (9). 
 Inferior Alveolar or Dental (10), divides into Incisor and Mental. 
 
 Pterygoid 
 
 Deep Temporal, ant. and poste- 
 rior. 
 
 Pterygoid Branches, to those 
 muscles. 
 
 Masseteric, to the masseter mus- 
 cle. 
 
 Buccal, to the buccinator 
 muscle. 
 
 S pheno-maxillary 
 
 Posterior Superior Alveolar (n). 
 Infra-orbital (12). 
 Descend. Palatine (13). 
 Vidian (a. canalis pterygoidea) 
 
 (16). 
 
 Pterygo-palatine (15). 
 Spheno-palatine or Naso-paia- 
 
 tine (14). 
 Pharyngeal. 
 
 The Internal Carotid Artery (a. carotis interna) commences at the 
 bifurcation of the common carotid and ascends in front of the transverse 
 processes of the three upper cervical vertebrae, and close to the tonsil, 
 traverses the carotid canal in the temporal bone, and after piercing the 
 
INTERNAL CAROTID ARTERY 127 
 
 dura mater close by the anterior clinoid process, divides into its terminal 
 (cerebral) branches. It curves remarkably in different parts of its course, 
 in the carotid canal and alongside the body of the sphenoid bone it de- 
 scribes a double curvature resembling the italic letter S placed horizon- 
 . tally. In the cervical portion no branches are given off; in the petrous, 
 cavernous and cerebral portions it gives off the following: 
 
 Tympanic (a. carotico- tympanic), enters the tympanum from the 
 carotid canal, and anastomoses on the membrana tympani with the 
 tympanic branch of the internal maxillary and the stylo-mastoid. 
 Arteries Receptaculi (aa. cavernosae), numerous small vessels going to 
 the walls of the sinuses, the Gasserian (semilunar) ganglion and the 
 pituitary body (hypophysis). 
 Anterior Meningeal, a small branch to the dura mater of the anterior 
 
 fossa, after passing over the lesser wing of the sphenoid. 
 Ophthalmic^ arises from the cavernous portion, enters the orbit through 
 the optic foramen, terminating at the inner angle of the eye into the 
 frontal and nasal branches. It gives off the following branches: 
 
 Ocular Group Orbital Group 
 
 Art. Centralis Retinae. Lacrimal. Frontal. 
 
 Muscular. Supra-orbital. Nasal. 
 
 Anterior Ciliary. Posterior Ethmoidal. (the 
 
 Short Ciliary. Anterior Ethmoidal. terminal. 
 
 Long Ciliary. Internal Palpebral. branches). 
 
 '**' Anterior Cerebral, joined to its fellow by the Anterior Communicating 
 Artery, about 2 lines long; then runs alongside its fellow, terminating 
 by anastomosis with the posterior cerebral arteries, and giving off the 
 following branches: 
 
 Antero-median Ganglionic or Basal. 
 Inferior Internal or Medial Frontal. 
 Ant. Internal or Medial Frontal. 
 Middle Internal or Medial Frontal. 
 Posterior Internal or Medial Frontal. 
 
 Middle Cerebral (a. cerebri media), in the fissure of Sylvius; divides 
 into: 
 
 Antero-lateral Ganglionic or Basal. Ascending Frontal. 
 
 Inferior External or Lateral Frontal. Ascending Parietal. 
 
 Parieto-temporal. 
 
 Posterior Communicating, anastomoses with the posterior cerebral, 
 a branch of the basilar, and gives off the: 
 
128 HUMAN ANATOMY 
 
 Postero-median Ganglionic, branches supplying the optic thalami 
 
 and the walls of the 3rd ventricle. 
 Anterior Choroid,to the hippocampus major, corpus fimbriatum, etc. 
 
 and ends in the choroid plexus. 
 
 [The vertebral Artery, a branch of the Subclavian, and the Basilar Artery, 
 formed by the junction of the two vertebrals, may be considered arteries 
 of the head and neck, but they are most conveniently described as branches 
 of the Subclavian Artery (see below.)] 
 
 THE CIRCLE OF WILLIS 
 
 The Circle of Willis (circulus arteriosus) is a remarkable anastomosis 
 at the base of the brain, formed by the branches of the vertebral and in- 
 ternal carotid arteries, and giving origin to the 3 trunks which supply 
 each cerebral hemisphere. Posteriorly, the two Vertebral arteries unite 
 to form the Basilar, which ends in the two Posterior Cerebral. Anteriorly, 
 each Internal Carotid gives off the Anterior Cerebral, these latter being 
 connected by the short Anterior Communicating artery. The circle is 
 completed by the Posterior Communicating arteries, one on each side, 
 which connect the posterior cerebral with the internal carotid. 
 
 The Circle of Willis gives off, anteriorly, the anterior cerebral arteries; 
 antero-laterally, the middle cerebral; and posteriorly, the posterior cerebral; 
 each artery giving origin to two very different arterial systems: the Cen- 
 tral Ganglionic System, supplying the central ganglia of the brain; the 
 Cortical Arterial System, which ramifies the pia mater and supplies the 
 cortex and subjacent medullary substance. The two systems, though 
 having a common origin, do not communicate afterwards, and in their 
 distribution are entirely independent of each other. Hence, between the 
 parts supplied by each, there is a zone of diminished nutritive activity, 
 where softening may be especially liable to occur in the brains of old people. 
 By the Circle of Willis the cerebral circulation is equalized and provision 
 made for carrying it on if one or more of the branches should be 
 obliterated. 
 
 THE TRIANGLES OF THE NECK 
 
 Anterior Triangle of the Neck is bounded, in front, by a line extending 
 from the chin to the sternum; behind, by the anterior margin of the 
 sterno-mastoid muscle; its base, directed upward, is formed by the lower 
 border of the body of the jaw and a line extending from the angle of the 
 jaw to the mastoid process; its apex is below, at the sternum. It is 
 crossed by the digastric muscle above and the anterior belly of the omo- 
 hyoid below, dividing it into 3 smaller triangles, named from below up- 
 
TRIANGLES OF THE NECK I 29 
 
 ward the Inferior Carotid, the Superior Carotid, and the Submaxillary 
 or Submandibular triangles. 
 
 Inferior Carotid Triangle, situated below the anterior belly of the omo- 
 hyoid, contains at it's posterior edge in a common sheath the lower portion 
 of the common carotid artery, the pneumogastric nerve and the internal 
 jugular vein, concealed by the sterno-mastoid muscle, also other structures, 
 which with the former may be summarized as follows: 
 Muscles, the sterno-hyoid and sterno-thyroid, covering the common 
 
 carotid artery. 
 
 Arteries, the common carotid and the inferior thyroid. 
 Veins, the internal jugular, as described above. 
 
 Nerves, the pneumogastric (n. vagus) recurrent laryngeal, and 
 sympathetic, also filaments from the loop between the descendens and 
 communicans hypoglossi. 
 
 Other Structures, the trachea, thyroid gland, and the lower part of the 
 larynx. 
 
 Superior Carotid Triangle, situated above the anterior belly of the omo- 
 hyoid, contains the upper part of the common carotid artery and its 
 bifurcation into the internal and external carotid, also other structures, 
 all summarized as follows: 
 
 Muscles, parts of the thyro-hyoid, hyo-glossus, inferior and middle con- 
 strictors of the pharynx. 
 
 Vessels, the common carotid artery, the internal and external carotid 
 arteries, and the internal jugular vein; the superior thyroid, lingual, 
 facial (external maxillary), occipital and ascending pharyngeal 
 branches of the external carotid and the veins accompanying them. 
 Nerves, the pneumogastric (n. vagus), spinal accessory (n. accesso- 
 rius), hypoglossal, descendens hypoglossi, sympathetic, internal and 
 external laryngeal. 
 Other Structures, the upper part of the larynx, and the lower part of the 
 
 pharynx. 
 
 Sub-mandibular or Sub-maxillary Triangle, immediately below the 
 body of the jaw, and above the posterior belly of the digastric and the 
 stylo-hyoid; contains the following: 
 
 Muscles, the mylo-hyoid, hyo-glossus, stylo-glossus, and stylo- 
 
 pharyngeus. 
 
 Arteries, the external and internal carotid; also the facial (external 
 maxillary), posterior auricular, temporal, internal maxillary, sub- 
 mental, and mylo-hyoid arteries. 
 Veins, the facial and internal jugular, 
 o 
 
130 HUMAN ANATOMY 
 
 Nerves, the pneumogastric (n. vagus), glosso-pharyngeal, facial, and 
 
 mylo-hyoid. 
 Glands, the parotid and sub-maxillary (sub-mandibular). 
 
 Posterior Triangle of the Neck is bounded, in front by the sterno- 
 mastoid muscle; behind, by the trapezius; its base corresponds to the 
 middle third of the clavicle, its apex is at the occiput. It is crossed by 
 the posterior belly of the omo-hyoid muscle about an inch above the 
 clavicle, subdividing it into two smaller triangles, the Occipital above, and 
 the Subclavian below. 
 
 Occipital Triangle, the larger division of the posterior triangle of the 
 neck, above the posterior belly of the omo-hyoid muscle, contains the 
 following: 
 
 Muscles, the splenius, levator anguli scapulae (m. levator scapulae), 
 
 middle and posterior scaleni. 
 Vessels, the transversalis colli artery and vein. 
 Nerves, the spinal accessory (n. accessorius), and descending branches 
 
 of the cervical plexus. 
 Glands, a chain of lymphatic glands. 
 
 Subclavian Triangle, the smaller of the divisions of the posterior triangle 
 of the neck, situated below the posterior belly of the omo-hyoid muscle, 
 and above the middle third of the clavicle, contains the following: 
 Vessels, the subclavian artery, the Subclavian vein occasionally, the 
 transversalis colli and suprascapular arteries (a. transversa scapulae), 
 and veins, the external jugular and transverse cervical veins. 
 Nerves, the brachial plexus, descending branches of the cervical plexus. 
 
 nerve to the subclavius muscle. 
 Glands, a lymphatic gland. 
 
 ARTERIES OF THE UPPER EXTREMITY 
 
 The Subclavian Artery (Arteria Subclavia) arises on the right side from 
 the innominate, of the left side from the arch of the aorta, and is divided 
 into 3 portions by the scalenus anticus muscle, which crosses it just 
 external to the origin of the thyroid axis, viz. the parts internal, behind, 
 and external to that muscle. At the outer border of the ist rib, the sub- 
 clavian becomes the Axillary Artery. Its upper border is a little above 
 the clavicle, and it is separated from the subclavian vein by the scalenus 
 anticus at its origin from the first rib. Its branches are all given from its 
 first portion, except the Superior Intercostal, which on the right side 
 arises from the second portion. Its branches are the 
 
SUBCLAVIAN ARTERY 
 
 FIG. 66. 
 
 VERTEBRAL (a. vertebralis) (6), passing up the neck, through the fora- 
 mina in the transverse processes of six cervical vertebrae, enters the 
 skull by the foramen magnum, where it joins its fellow to form the 
 Basilar Artery. Its branches are- 
 Lateral Spinal Branches. 
 
 Muscular Branches. 
 
 Posterior Meningeal. 
 
 Anterior Spinal. 
 
 Posterior Spinal. 
 
 Posterior Inferior Cerebellar. 
 
 Bulbar. 
 
 The Basilar (a. basilaris), formed 
 by the junction of the vertebrals, 
 gives off on each side a transverse, 
 anterior, and superior cerebellar, 
 and ends in the two posterior cere- 
 bral. (See Circle of Willis, pages 
 151 and 158.) 
 
 THYROID Axis (truncus thyreocervi- 
 calis) (8), at once divides into the 
 three following branches. 
 
 Inferior Thyroid (a. thyreoidea inferior) (7), to the thyroid gland, 
 giving off 
 
 Inferior Laryngeal. CEsophageal Branches. 
 
 Tracheal. Muscular. Ascending Cervical (9). 
 
 2 Terminal. 
 
 Suprascapular (a. transversa scapulae) (12), to the shoulder- joint 
 and the dorsum of the scapula, anastomosing there with the pos- 
 terior and subscapular. 
 
 Transversalis Colli (n), divides beneath the margin of thetrapezius 
 into 
 
 Superficial Cervical (ramus ascendens). 
 Posterior Scapular (ramus descendens). 
 
 INTERNAL MAMMARY (a. mammaria interna) (13), arises opposite the 
 thyroid axis, descends behind the costal cartilages, and ends at the 
 6th interval, in the musculo-phrenic and superior epigastric, the 
 latter anastomosing with the deep epigastric branch of the external 
 iliac. Its branches are the 
 
132 HUMAN ANATOMY 
 
 Comes Nervi Phrenici Paricardiac. Perforating, 
 
 (pericardiaco-phrenic), Sternal. Musculo-phrenic. 
 
 or Superior Phrenic. Anterior Intercostal. Superior Epigastric. 
 / Mediastinal. 
 
 '" SUPERIOR INTERCOSTAL (a. intercostalis suprema) (14), gives off 
 branches in the intercostal spaces to the posterior spinal muscles 
 and to the spinal cord. One branch, the 
 
 Profunda Cervids (a. cervicalis profunda) (10), supplies the mus- 
 cles of the back of the neck, and anastomoses with the arteria 
 princeps cervicis (ramus descendens a. occipitalis) of the occipital. 
 This vessel occasionally arises from the subclavian artery. 
 1 The Axillary Artery (a. axillaris) (5), the continuation of the subclavian, 
 commences at the outer border of the first rib, and terminates at the lower 
 border of the tendon of the teres major muscle, where it becomes the 
 brachial artery. The pectoralis minor crosses it and marks its division 
 into three portions, ist, above; 2nd behind, and 3rd below that muscle. 
 The brachial plexus is in close relation with the artery, surrounding it on 
 three sides in the second portion. Its branches are 7 in number as 
 follows: 
 
 Superior Thoracic (a. thoracalis suprema), from the first portion; 
 
 supplies the pectoral muscles and the walls of the thorax. 
 Acromial Thoracic (a. thoraco-acromialis), from the first portion; 
 divides into the 
 Thoracic (pectoral) Branches 2 or 3, to the serratus magnus (m. 
 
 serratus anterior) and pectorals. 
 Acromial Branches, to the deltoid muscles. 
 Descending or Humeral (deltoid), to the pectoralis major and 
 
 deltoid. 
 
 Clavicular, a very small branch, to the subclavius muscle. 
 Mar Thoracic, from the second portion; to the glands and theareolar 
 
 tissue of the axilla. 
 
 Long Thoracic (a. thoracalis lateralis or external mammary), from 
 " tlie second portion; to the serratus magnus (m. serratus anterior), 
 
 the pectoral muscles and the mammary gland. 
 
 Subscapular (a. subscapularis), from the third portion; to the inferior 
 angle of the scapula, where it anastomoses with the long thoracic, 
 the intercostal and the posterior scapular (ramus descendens a. 
 transversalis Colli) arteries. It gives off small branches to the del- 
 toid and triceps muscles, and the 
 
 Dorsalis Scapulae (a. circumflexa scapulae), a large branch, to 
 the subscapular fossa and the axillary border of the scapula. 
 
ARTERIES OF THE UPPER EXTREMITY 133 
 
 Posterior Circumflex (a. circumflexa humeri posterior), from the third 
 portion; winds around the neck of the humerus to the deltoid muscle 
 and the shoulder-joint, anastomosing with the anterior circumflex 
 and other arteries. 
 
 Anterior Circumflex (a. circumflexa humeri anterior), from the third 
 portion; winds around the neck of the humerus, to the head of that 
 bone, the deltoid muscle and the shoulder-joint, anastomosing with 
 the posterior circumflex. 
 
 The Brachial Artery (a. Brachialis) is the continuation of the axillary 
 from the lower margin of the teres major tendon to its bifurcation into the 
 radial and ulnar, which is usually about half an inch below the bend of the 
 elbow. The median nerve crosses it from the outside to the inside about 
 its middle. Above its bifurcation it is crossed diagonally by the bicipital 
 fascia (lacertus fibrosus). The basilic vein lies on its inner side but sepa- 
 rated from it in the lower part of the arm by the deep fascia. Its branches 
 are the 
 
 Superior Profunda (a. profunda brachii), winds over the arm in the 
 spiral groove (sulcus radialis), giving off the posterior articular to 
 the elbow anastomosis, and a branch to anastomose with the recur- 
 rent branch of the radial, and a nutrient artery to the bone. This 
 artery supplies the triceps muscle. 
 
 Nutrient Branch, enters the nutrient canal of the humerus. 
 Inferior Profunda (a. collateralis ulnaris superior), to the elbow-joint 
 
 anastomosis. 
 
 - Anastomotica Magna (a. collateralis ulnaris inferior], anastomoses 
 with the posterior articular, inferior profunda (superior ulnar col- 
 lateral) anterior and posterior ulnar recurrent. 
 Muscular Branches, to the muscles in the course of the artery. 
 
 The Radial Artery (a. radialis) extends from the bifurcation of the 
 brachial to the deep palmar arch, and gives off the following branches: 
 In the Forearm, 
 
 Radial Recurrent, to the supinators, the brachialis anticus and the 
 elbow joint, anastomosing with the terminal branches of the superior 
 profunda (a. profunda brachii). 
 
 *'- Muscular Branches, to the muscles on the radial side of the forearm. 
 Anterior Carpal (ramus carpeus volaris), anastomoses with the anterior 
 carpal of the ulnar artery, forming the Anterior Carpal Arch (rete 
 carpi volare). 
 Superficialis Voice, to the muscles of the thumb. 
 
134 HUMAN ANATOMY 
 
 In the Wrist, 
 
 Posterior Carpal (ramus carpeus dorsalis), anastomoses with the pos- 
 terior carpal of the ulnar artery forming the Posterior Carpal Arch 
 (rete carpi dorsale). 
 
 Metacarpal, the first dorsal interosseous branch, divides into two 
 dorsal digital branches, supplying the adjoining sides of the index 
 and middle fingers. 
 
 7 Dor sales Pollicis 2, along the sides of the thumb. 
 Dorsalis Indicis, along the radial side of the index finger. 
 Ln the Hand, 
 
 Princeps Pollicis, along the sides of the palmar aspect of the thumb by 
 two branches forming an arch. 
 
 Radialis Indicis (a. volaris indicis radialis), along the radial side of 
 the index finger to anastomose with the collateral digital and the 
 princeps pollicis, giving a communicating branch to the superficial 
 palmar arch (arcus volaris superficialis). 
 
 Perforating 3, backward from the deep palmar arch to anastomose 
 with the dorsal interosseous arteries. 
 
 Palmar Interosseous 3 or 4, from the deep palmar arch, on the inter- 
 ossei muscles to anastomose with the digital branches of the super- 
 ficial arch (arcus volaris superficialis). 
 
 Palmar Recurrent, from the deep palmar arch to the carpal joints, 
 anastomosing with the anterior carpal arch (rete carpi volare). 
 
 The Ulnar Artery (a. ulnaris) extends from the bifurcation of the 
 brachial just below the bend of the elbow along the ulnar border of the 
 forearm to the wrist. Immediately beyond the pisiform bone it divides 
 into two branches which enter into the formation of the superficial and 
 deep palmar (volar) arches. Its branches are as follows: 
 In the Forearm, 
 
 Anterior Ulnar Recurrent (a. recurrentes ulnaris anterior), anastomoses 
 in front of the inner condyle of the humerus with the anastomotica 
 magna (inferior ulnar collateral) and the inferior profunda (superior 
 ulnar collateral). 
 
 Posterior Ulnar Recurrent (a. recurrentes ulnaris posterior), anasto- 
 moses behind the inner condyle of the humerus with the anastomotica 
 magna (inferior ulnar collateral), inferior profunda (superior ulnar 
 collateral) and interosseous recurrent. 
 
 Interosseous, about % inch long, divides into two branches. The 
 Anterior Interosseous (volar interosseous) gives off the Median 
 Artery to the median nerve and a Nutrient branch to both bones of the 
 
ARTERIES OF THE FOREARM AND HAND 135 
 
 forearm. The Posterior (dorsal) Interosseous gives off near its origin 
 the Interosseous Recurrent to the elbow-joint anastomosis. 
 
 Muscular,- to the muscles on the ulnar side of the forearm. 
 In the Wrist, 
 
 Anterior Carpal, (ramus carpeus volaris), anastomoses with a cor- 
 responding branch of the radial artery in front of the carpus. 
 
 Posterior Carpal (ramus carpeus dorsalis), anastomoses with a cor- 
 responding branch of the radial artery forming the posterior carpal 
 arch (rete carpi dorsale). 
 In the Hand, 
 
 Deep or Communicating (ramus volaris profunda), anastomoses with 
 the termination of the radial artery, completing the deep palmar 
 arch (arcus volaris profundus). 
 
 Superficial Palmar Arch (arcus volaris superficialis), is the continua- 
 tion of the trunk of the ulnar artery in the hand. 
 
 Digital 4, given off by the superficial palmar arch (arcus volaris 
 
 "superficialis). 
 - S V THE CARPAL ARCHES 
 
 The Anterior Carpal Arch (rete carpi volare) is formed by the anastomo- 
 sis of the anterior carpal of the radial with the anterior (volar) carpal 
 of the ulnar artery in front of the wrist. It is joined by branches 
 from the anterior (volar) interosseous above and by recurrent branches 
 from the deep palmar (volar) arch below, and gives off branches to 
 supply the articulations of the wrist and carpus. 
 
 The Posterior Carpal Arch (rete carpi dorsale) is formed by the 
 anastomosis of the posterior (dorsal) carpal of the radial with the posterior 
 (dorsal) carpal of the ulnar artery. It is joined by the termination of the 
 anterior (volar) interosseous artery and gives off dorsal interosseous 
 arteries for the third and fourth interosseous spaces, which divide into 
 dorsal digital branches which supply the adjacent sides of the middle, 
 ring and little fingers, and communicate with the digital arteries of the 
 superficial palmar (volar) arch, and at their origin with the perforating 
 branches from the deep palmar (volar) arch. 
 
 THE PALMAR ARCHES 
 
 The Superficial Palmar Arch (arcus volaris superficialis) is formed by 
 the part of the ulnar artery which lies in the palm of the hand, and is 
 completed by that artery anastomosing with a branch from theradialis 
 indicis, at the root of the thumb; sometimes with the superficialis volae 
 or the princeps pollicis of the radial. It gives off 4 Digital Collateral 
 
136 HUMAN ANATOMY 
 
 branches to the sides of the fingers, except the radial side of the index 
 finger, which with the thumb is supplied from the radial artery. 
 
 The Deep Palmar Arch (arcus volaris profundus) is formed by the 
 palmar portion of the radial artery, and is completed by the anastomosis of 
 that artery with the deep palmar (communicating) branch of the ulnar. 
 It lies upon the carpal ends of the metacarpal bones and the interossei 
 muscles, about ^ inch nearer to the carpus than the superficial palmar 
 (volar) arch, from which it is separated by the transverse carpal ligament, 
 the flexor brevis minimi digiti, (m. flexor digiti quinti brevis) the super- 
 ficial flexor tendons and divisions of the median and ulnar nerves. From 
 it are given off the radialis indicis, palmar (volar) interosseous, perforating 
 and palmar (volar) recurrent branches of the radial artery. 
 
 ARTERIES OF THE TRUNK 
 THE DESCENDING AORTA (AORTA DESCENDENS) 
 
 The Descending Aorta is divided into two portions, the Thoracic Aorta 
 (aorta thoracalis) and the Abdominal Aorta (aorta abdominalis), cor- 
 responding to the two great cavities of the trunk in which they are 
 situated. 
 
 The Thoracic Aorta (aorta thoracalis) commences at the lower border of 
 the 4th thoracic vertebra on the left of the spine, and descends in the back 
 part of the posterior mediastinum, terminating at the aortic opening in the 
 diaphragm directly in front of the lower border of the last thoracic vertebra. 
 Its branches are 
 
 Pericardia!, irregular in origin, to the pericardium. 
 Bronchial, vary in number and origin; generally one on the right side 
 and two on the left. They nourish the lungs, bronchial glands and 
 the oesophagus. 
 (Esqpjiageal, 4 or 5, anastomose on the oesophagus with branches of the 
 
 inferiorThyroid, phrenic, and gastric arteries. 
 Posterior Mediastinal, numerous small vessels supplying the glands and 
 
 the areolar tissue in the mediastinum. 
 
 Intercostals, usuallvjj on each side, the two superior intercostal spaces 
 being supplied by the superior intercostal branch of the subclavian. 
 They run between the two layers of intercostal muscles, anastomose 
 with the anterior intercostal branches of the internal mammary, and 
 each gives off the following branches: 
 
 Posterior or Dorsal, to the muscles and skin of the back. 
 
 Spinal, to the spinal cord and its membranes. 
 
 Collateral Intercostal, along the upper border of the rib below. 
 
ABDOMINAL AORTA 
 
 137 
 
 FIG. 67. 
 
 .The Abdominal Aorta (aorta abdominalis) begins where the thoracic 
 aorta ends (see p. 123) and terminates on the body of the 4th lumbar 
 vertebra, where it divides into the two common iliac arteries. Its branches 
 are as follows: 
 
 2 Inferior Phrenic (i), one on each side, but usually only one arises 
 from the aorta, the other springing from either the coeliac axis or the 
 renal artery. They go to the under surface of the diaphragm, where 
 each a rtery divides into two 
 branches, an external and an in- 
 ternal, the former to the side the 
 latter to the front of the thorax 
 and the diaphragm. 
 CCELIAC Axis (a. coeliaca) (2), arises 
 from the aorta, close to the margin 
 of the opening in the diaphragm, 
 runs forward for half an inch, and 
 divides into the Left Gastric, He- 
 patic, and Splenic (a. lienalis) arte- 
 ries, occasionally giving off one of 
 the phrenics. The 
 Js'ft Gastric (a. gastrica sinistra) (3), 
 supplies the stomach along its 
 lesser curvature, anastomosing 
 with the aortic cesophageal, splenic 
 (a lienalis), and hepatic branches. 
 JIeatic (a. hepatica) (4), forms the 
 lower boundary of the foramen of 
 Winslow (foramen epiploicum), 
 passes upward to the transverse 
 fissure (porta hepatis) of the liver 
 where it divides into two branches, 
 right and left, supplying the corre- 
 sponding lobes of that organ. Its 
 branches are the 
 
 Pyloric (a. gastrica dextra), to 
 the pyloric end of the stomach 
 and along the lesser curvature 
 of that viscus. 
 
 Gastro-duodenalis, giving off the Gastro-epiploica Dextra along 
 the greater curvature of the stomach, and the Pancreatico-duo- 
 
138 HUMAN ANATOMY 
 
 denalis Superior to the contiguous margins of the duodenum and 
 pancreas. 
 Right Hepatic, to the right lobe of the liver, giving off the Cystic 
 
 Artery to the gall-bladder. 
 Left Hepatic, to the left lobe of the liver. 
 
 Splenic (a. lienalis) (5), the largest, branch of the cceliac axis, passes by 
 ^""a very tortuous course to the spleen, giving off the following: 
 
 Pancreaticae Parvae. Gastric (VasaBrevia) (a.a. gastricae breves) 
 
 to the stomach. 
 Pancreatica Magna. Gastro-epiploica Sinistra, to the stomach. 
 
 Terminal Branches, enter the hilum of the spleen. 
 
 Superior Mewnteric (a. mesenterica superior) (9), supplies the small 
 intestine, caecum, ascending and transverse colon. Arising about 
 % inch below the cceliac axis it arches forward, downward, and to 
 the left, giving off the 
 
 Inferior Pancreatico-duodenal. Ileo-colic. 
 Vasa Intestini Tenuis (aa. in- Colica Dextra and Media. 
 testinales), 12 to 15. 
 
 V " Supra-renal (a. supra-renalis media) (6), arise one on each side, 
 opposite the origin of the superior mesenteric, passing to the supra- 
 renal capsules. 
 
 2 Renal (aa. renales) (7), one from each side, just below the preceding, 
 pass to the kidney, at its hilum having the middle place between the 
 ureter behind and the renal vein in front. U. A. V. (you 'ave!) 
 
 2 Spermatic (aa. spermaticae internae) (10), one on each side, in the male 
 through the inguinal canal to the testes; in the female it is called 
 Ovarian (a. ovarica), going to the ovaries, uterus and skin of the 
 labia and groins. 
 
 Inferior Mesenteric (a mesenterica inferior) (n), supplies the descend- 
 ing colon, sigmoid flexure, and most of the rectum, giving off the 
 following branches: 
 
 Colica Sinistra. Sigmoid (aa. sig- Superior Hemorrhoidal. 
 moidece). 
 
 Lumbar (aa. lumbales) (8), usually 4 on each side, analogous to the 
 intercostals. They each divide into two branches, the 
 
 Dorsal, giving off a spinal branch. Abdominal. 
 Middle Sacral (a. sacralis media) (12), arises just at the bifurcation of 
 
 
 / 
 
THE ILIAC ARTERIES 139 
 
 the aorta; it descends along the last lumbar vertebra and the front 
 of the sacrum to the upper part of the coccyx, giving off numerous 
 branches on each side to anastomose with the lateral sacral arteries. 
 It terminates in a minute branch which goes to the coccygeal gland 
 (Luschka), and sends off branches to the rectum. 
 
 THE ILIAC ARTERIES (ARTERLE ILIAC.E) 
 
 The Common Iliac Arteries (aa. iliacae communes) extend from the 
 bifurcation of the aorta at the 4th lumbar vertebra to the lumbo-sacral 
 articulation, where each divides into the External Iliac (15) and the 
 Internal Iliac (a. hypogastrica) (14); the former supplying the lower 
 extremity, the latter going to the viscera and walls of the pelvis. The 
 common iliac arteries are about 2 inches in length, the right being a little 
 longer than the left, and each is crossed by the ureter, just before its 
 bifurcation. 
 
 The Internal Iliac (arteria hypogastrica) (14) is about i% inches long, 
 extending from the lumbo-sacral articulation to the great sacro-sciatic 
 notch, where it divides into an anterior and a posterior trunk. From the 
 Anterior Trunk are given off, from above downward, the 
 
 Superior Vesical (a. vesicalis superior), the remaining previous part, 
 of the fcEtal hypogastric artery. It sends branches to the bladder 
 the vas deferens and the ureter; and one, the Middle Vesical, to the 
 base of the bladder. 
 
 Obturator (a. obturatoria), through the canal in the obturator mem- 
 brane to the thigh, where it divides into an internal and external 
 branch. Within the pelvis it gives off an iliac, a vesical, and a pubic 
 branch. In one out of every 3^ cases this artery arises from the 
 deep epigastric (a. epigastrica inferior), in 2 out of every 3 from the 
 internal iliac (a. hypogastrica), in i out of 7^ by two roots from both 
 vessels and in about the same proportion from the external iliac. 
 Inferior Vesical (a. vesicalis inferior), to the bladder, prostrate gland, 
 and vesiculae seminales. In the female this artery is called the 
 Vaginal (a. vaginalis). 
 Middle Hemorrhoidal (a. haemorrhoidalis medialis), to the anus and 
 
 parts outside the rectum. 
 
 Uterine (a. uterina), in the female, anastomosing with a branch 
 
 (ramus ovarii) from the ovarian. It gives off cervical branches to 
 
 the cervix uteri and the azygos arteries of the vagina. 
 
 Internal Pudic (a. pudenda interna), the smaller of the terminal 
 
 branches of the anterior trunk, supplies the external generative 
 
140 HUMAN ANATOMY 
 
 organs. Its muscular branches in the pelvis are numerous and small; 
 in the perineum they are the 
 
 Inferior Hemorrhoidal (a. Artery of the Bulb (a. bulbi 
 
 haemorrhoidalis inferior). urethrae). 
 
 Superficial Perineal (a. Urethral (a. urethralis). 
 
 perinei). Artery of the Corpus Cavernosum 
 
 Transverse Perineal (a. (a. profunda penis). 
 
 trans versa perinei). Dorsal Artery of the Penis (a dor- 
 
 salis penis). 
 
 Sciatic (a. glutaea), the other terminal branch, supplies the muscles on 
 the back of the pelvis. Its branches are the 
 Muscular (internal), rami musculares. 
 Hemorrhoidal Brs. 
 Vesical Branches. 
 Coccygeal. 
 Cutaneous. 
 
 Comes Nervi Ischiadici, (a. comitans n. ischiadici). 
 Muscular (ext.), (rami musculares). 
 Anastomotic. 
 Articular. 
 THE POSTERIOR TRUNK gives off the following: 
 
 Ilio-lumbar (a. ilio-lumbalis), dividing into a lumbar and an ilica 
 
 branch. 
 Lateral Sacral (arteriae sacrales laterales), superior and inferior on each 
 
 side. 
 
 Gluteal (a. glutaea superior), the continuation of the posterior trunk, 
 divides into a superficial and a deep branch, to the glutei muscles, 
 the skin over the sacrum, and the hip-joint. Before dividing it gives 
 a nutrient branch to the ilium, and some muscular branches. 
 The External Iliac (a. iliaca externa) extends to beneath the centre of 
 Poupart's ligament (l.inguinale), where it enters the thigh and becomes the 
 Femoral Artery; lying between the femoral vein on the inside and the 
 anterior crural nerve (n. femoralis) on the outside V.A.N. Its branches 
 are small muscular and glandular, and the - 
 
 Deep Epigastric (a. epigastrica inferior), which arises a few lines above 
 Poupart's inguinal ligament, passes between the peritoneum and the 
 transversalis fascia, to the sheath of the rectus which it enters 
 and ascends behind that muscle, to anastomose by numerous branches 
 with the terminal branches of the internal mammary and inferior 
 intercostal. It gives off the 
 
THE FEMORAL ARTERY 141 
 
 Cremasteric (a. spermaticainthe male; a. ligament! teres uteri in 
 
 the female). 
 
 Pubic. Muscular Branches (rami musculares). 
 
 Deep Circumflex Iliac (a. circumflexa ilium profunda), arises opposite 
 to the epigastric, passes along the crest of the ilium to about its 
 middle, where it pierces the transversalis and runs backward between 
 that muscle and the internal oblique to anastomose with the ilio- 
 lumbar, gluteal (a. glutaea superior), lumbar and epigastric ateries. 
 
 ^'5*4 ARTERIES OF THE LOWER EXTREMITY 
 
 The Femoral Artery (arteria femoralis) extends from Poupart's liga- 
 ment (1. inguinale) to the opening in the adductor magnus, where it 
 becomes the popliteal artery. Its course corresponds to a line drawn 
 from a point midway between the anterior superior spine of the ilium and 
 the spine of pubis, to the inner side of the inner condyle of the femur. 
 It lies in a strong fibrous sheath with the femoral vein, but divided from 
 the latter by a fibrous partition. It may be divided into two portions, 
 the Common Femoral and the Superficial Femoral, for convenient de- 
 scription, as follows: 
 
 The Common Femoral Artery, about 2 inches long, is very superficial, 
 rests on the inner margin of the psoas muscle, which separates it from 
 the capsular ligament of the hip-joint, and is covered by the skin, 
 superficial fascia, superficial inguinal glands, iliac portion of the fascia 
 lata, and the anterior part of the sheath of the vessels. 
 The Superficial Femoral Artery, is only superficial in Scarpa's triangle 
 (femoral trigone), being deeper in Hunter's canal (adductor canal). 
 It lies above on the femoral vein and the profunda artery and vein; 
 below, on the adductor longus and adductor magnus muscles. The 
 internal saphenous nerve crosses it from without inward. 
 Branches of the Femoral Artery, are as follows: 
 Superficial Epigastric (a. epigastrica superficialis) (c), through the 
 saphenous opening (fossa ovalis) to ascend on the abdomen, giving 
 off branches to the skin, the superficial fascia and the superficial 
 inguinal glands. 
 
 Superficial Circumflex Iliac (a. circumflexa ilium superficialis) (;'), to 
 the crest of the ilium, supplying the skin of the groin, the superficial 
 fascia, and the superficial inguinal glands. 
 
 Superficial External Pudic (a. pudenda externa superficialis) (d), 
 through the saphenous opening (fossa ovalis) to the skin of the 
 abdomen, the penis and the scrotum (and the labium in the female). 
 
142 
 
 HUMAN ANATOMY 
 
 FIG. 68. 
 
 Deep External Pudic (a. pundenda externa profunda) (d), to the skin of 
 
 the scrotum and perinseum (and the labium in the female). 
 Muscular (rami musculares). 
 
 Profunda Femoris (Deep Femoral Artery) (e), arises posteriorly about 
 i or 2 inches below Poupart's (inguinal) ligament, and descends to 
 the lower third of the back of the thigh, giving off the following 
 branches: 
 
 Ext. Circumflex (a. circumflexa femoris 
 
 lateralis) (g). 
 Int. Circumflex (a. circumflexa femoris 
 
 medialis) (/). 
 
 3 Perforating (aa. perforantes) (h). 
 Terminal or 4th perforating. 
 Muscular Branches (rami musculares) (&), 
 
 to the sartorius and vastus internus. 
 Anastomotica Magna (a. genu suprema), 
 arises from the femoral in Hunter's (ad- 
 ductor) canal and divides into a super- 
 ficial and a deep branch, the latter anas- 
 tomosing around the knee-joint with the 
 superior external and internal articular 
 arteries, and the recurrent branch of the 
 aniecior tibial. 
 
 Scarpa's Triangle (Trigonum Femorale) is 
 a triangular space in the thigh which cor- 
 responds to the depression seen immediately 
 below the fold of the groin. Its apex is down- 
 ward, its base formed by Poupart's (inguinal) 
 ligament, and its sides externally by the sar- 
 torious, internally by the adductor longus. 
 Its floor is formed by the iliacus, psoas, pec- 
 tineus and adductor longus muscles, from 
 without inward. It is bisected vertically by 
 
 the femoral vessels, which extend from the middle of its base to its apex. 
 It also contains the anterior crural nerve (n. femoralis) external to the 
 vessels, together with lymphatic vessels and glands and some fat. 
 
 Hunter's Canal (Canalis Adductorius) is the interval between the ad- 
 ductor magnus and the vastus internus (m. vastus medialis) in the middle 
 third of the thigh, extending from the apex of Scarpa's triangle to the 
 femoral opening in the adductor magnus muscle, and lying beneath the 
 
ARTERIES OF THE LEG 143 
 
 sartorius. It contains the femoral vessels in their sheath, the vein lying 
 behind and to the outer side of the artery; also the long saphenous nerve, at 
 first external to and then in front of the vessels. 
 
 The Popliteal Artery (a. Poplitea), the continuation of the femoral, 
 extends from the opening in the adductor magnus, passing behind the 
 knee-joint, to the lower border of the popliteus muscle, where it divides into 
 the Anterior and Posterior Tibial Arteries. It is crossed by the popliteal 
 vein and the internal popliteal nerve (n. tibialis), and gives off the follow- 
 ing-named branches, which are distributed around the knee-joint in a free 
 anastomosis; except the Azygos Articular, which pierces the posterior 
 ligament of the joint to reach the internal ligaments and the synovial 
 membrane. Branches are named as follows: 
 i Superior Muscular Branches. 
 
 Inferior Muscular, or Sural. 
 
 Cutaneous Branches. 
 
 Superior Articular, internal (a. genu superior medialis) and external 
 (a. genu superior lateralis). 
 
 Azygos Articular (a. genu media). 
 
 Inferior Articular, internal (a. genu inferior medialis) and external 
 (a. genu inferior lateralis). 
 
 The Anterior Tibial Artery (a. Tibialis anterior) extends from the 
 bifurcation of the popliteal to the front of the ankle-joint, where it be- 
 comes the Dorsal is Pedis. It passes between the two heads of the tibialis 
 posticus (m. tibialis posterior) over the upper edge of the interosseous 
 membrane and along its anterior surface, resting on the tibia for its lower 
 third. It is accompanied by the anterior tibial nerve (n. peronaeus pro- 
 fundus) close to it externally, and is crossed below by the tendon of the 
 extensor proprius hallucis. Its branches are named the 
 
 Posterior Recurrent Tibial (a. recurrens tibialis posterior). 
 
 Superior Fibular. 
 
 Anterior Recurrent Tibial (a. recurrens tibialis anterior). 
 ^ Muscular (rami musculares). 
 
 Internal Malleolar (a. malleolaris anterior medialis). 
 
 External Malleolar (a. malleolaris anterior lateralis). 
 
 The Dorsalis Pedis Artery, the continuation of the anterior tibial, ex- 
 tends from the front of the ankle-joint along the tibial side of the foot, to 
 the back part of the ist intermetatarsal space, where it terminates in the 
 Dorsalis Hallucis and the Communicating (ramus plantaris profundus). 
 The anterior tibial nerve lies close to its outer side. Its branches are as 
 follows: 
 
144 HUMAN ANATOMY 
 
 * Tarsal (a. tarsalis lateralis), passing outward along the tarsus. 
 -) Metatarsal (a. arcuata), giving off 3 Interosseous (aa. metatarseae 
 
 dorsales), and the 7 Digital branched (aa. digitales dorsales). 
 Dorsalis Hallucis, to the great toe and the inner side of the second toe 
 
 by its 3 digital branches. 
 ; Communicating (ramus plantaris profundus), dips down into the sole 
 
 of the foot in the ist interosseous space of the metatarsus, to inosculate 
 
 with the external plantar, completing the plantar arch. Its plantar 
 
 digital branch, the arteria magna hallucis, supplies the inner side 
 
 of the great toe and the adjacent sides of the great and second toes, 
 
 on their plantar surfaces. 
 
 The Posterior Tibial Artery (A. Tibialis Posterior) is a large vessel, 
 extending from the bifurcation of the popliteal along the back of the tibia 
 to the fossa below the inner malleolus, where it divides into the Internal 
 (medial) and External (lateral) Plantar. The posterior tibial nerve crosses 
 it a short way below its origin and then lies near its outer side for the rest 
 of its course. Its branches are as follows: 
 / Peroneal (a. peronaea) , along the fibular side, giving off the following : 
 
 Muscular (rami musculares). 
 
 Nutrient of the fibula (a. nutrica fibulae). 
 
 Anterior Peroneal (ramus perforans). 
 
 Communicating (ramus communicans). 
 
 Posterior Peroneal. 
 
 External Calcanean (ramus calcaneus lateralis). 
 Nutrient of the Tibia (a. nutrica tibiae), the largest nutrient artery of 
 
 bone in the body. 
 Muscular Branches (rami musculares), to the posterior muscles of the 
 
 leg. 
 ' Communicating (ramus communicans), to join a similar branch of the 
 
 peroneal artery. 
 Internal Calcanean Branches (rami calcanei mediales), to the heel and 
 
 sole of the foot. 
 Internal Malleolar (a. malleolaris posterior medialis). 
 
 The Internal Plantar Artery (a. plantaris medialis), the smallest of the 
 terminal branches of the posterior tibial, passes along the inner side of the 
 foot and great toe. 
 
 The External Plantar Artery (a. plantaris lateralis) sweeps across the 
 plantar aspect of the foot in a curve, the convexity of which is directed 
 outward and forward; and at the interval between the bases of the ist 
 and 2d metatarsal bones it inosculates with the communicating branch 
 
IMPORTANT ARTERIAL ANASTOMOSES 145 
 
 frortl the dorsalis pedis, completing the Plantar Arch (arcus plantaris") 
 or the Stirrup Anastomosis. It gives off numerous muscular branches, 
 and the 
 Posterior Perforating (rami perforantes posteriores), 3 small branches 
 
 which ascend through the 3 outer interosseous spaces between the 
 
 heads of the dorsal interossei muscles. 
 Digital Branches (aa. digitales plantares), 4, supplying the sides of the 
 
 3 outer toes and the outer side of the 2d toe; its inner side, together 
 
 with the great toe, being supplied by the communicating branch of 
 
 the dorsalis pedis. 
 
 ARTERIAL ANASTOMOSES 
 
 The Anastomosis around the Shoulder- joint is formed by the following 
 8 arteries, viz. 
 
 Posterior Scapular (ramus descendens a. trans versa colli). 
 Subscapular (a. circumflexa scapulae) br. of axillary. 
 Dorsalis Scapula (a. circumflexa scapulae) br. of subscapular. 
 Infraspinous, br. of dorsalis scapulae. 
 S upr as ca pular (a. transversa scapulae), br. of thyroid axis. 
 Ant. Circumflex (a. circumflexa humeri anterior), br. of axillary. 
 Post. Circumflex (a. circumflexa humeri posterior), br. of axillary. 
 Acromial, br. of acromial thoracic. 
 
 The Anastomosis around the Elbow-joint is formed by the 
 
 Superior Profunda, (a. profunda brachii), br. of brachial. 
 
 Posterior Articular, br. of superior profunda. 
 
 Radial Recurrent, br. of radial. 
 
 Interosseous Recurrent, br. of posterior interosseous. 
 
 Inferior Profunda (a. collateralis ulnaris superior), br. of brachial. 
 
 Anastomotica Magna (a. collateralis ulnaris inferior), br. of brachial. 
 
 A nterior Ulnar Recurrent, br. of ulnar. 
 
 Posterior Ulnar Recurrent, br. of ulnar. 
 
 The Anastomotica Magna is the vessel most engaged in this anastomosis, 
 the only part in which it is not employed being that in front of the ex- 
 ternal condyle of the humerus. 
 
 The Anastomosis around the Hip-joint is formed by the 
 Gluteal (superior gluteal), Ilio-lumbar, and Circumflex Iliac, with the Ex- 
 ternal Circumflex. 
 
 Obturator and Sciatic (inferior gluteal), with the Internal Circumflex. 
 Comes Nervi Ischiadici, with the Perforating branches of the Profunda. 
 10 
 
146 HUMAN ANATOMY 
 
 The Arteries Anastomosing around the Knee-joint are the 
 
 Descending, br. of ext. circumflex. Sup. Int. Articular, br. of popliteal. 
 Anastomotica Magna (a. genu su- Inf. Ext. Articular, br. of popliteal. 
 
 prema), br. of femoral. Inf. Int. Articular, br. of popliteal. 
 
 Inferior Perforating, br. of profunda. Ant. Recurent, br. of anterior tibial. 
 Superior Ext. Articular, br. of popliteal. 
 
 This anastomosis is sometimes called the deep plexus of the Circum- 
 patellar Anastomosis; a superficial arterial plexus being situated between 
 the fascia and skin around the patella. 
 
 .The Crucial Anastomosis is formed behind the junction of the neck of 
 the femur with the great trochanter, between the adductor magnus and 
 quadratus femoris muscles, by the anastomosis of the following-named 
 arteries: 
 
 Transverse branch of Ext. Circumflex (from profunda), externally. 
 
 Terminal branch of Int. Circumflex (from profunda), internally. 
 
 First Perforating branch of the Profunda Femoris, below. 
 
 Anastomotic branch of the Sciatic (from. int. iliac), above. 
 
 The Longest Anastomosis in the Body is that between the subclavian 
 and the external iliac by the anastomosis of the Superior Epigastric, br. 
 of the internal mammary, with the Deep Epigastric, br. of the external 
 iliac. 
 
 [The circle of Willis has been described on page 128; the palmar and 
 plantar arches on pages 135 and 145 respectively; and the anastomosis 
 of the membrana tympani on page 298.] 
 
 The Collateral Circulation, after Ligature of the Common Carotid 
 Artery, is established by the free communication existing between the 
 carotid arteries of opposite sides both within and without the cranium, 
 and by enlargement of the branches of the subclavian artery on the ligated 
 side. Outside the skull the principal communication takes place by 
 the following anastomoses: 
 
 Superior Thyroid, br. of the external carotid, with the Inferior Thyroid, 
 br. of the thyroid axis (from the subclavian). 
 
 Arteria Princeps Cervicis, br. of the occipital (from the external carotid), 
 with the Vertebral, br. of the subclavian, and the Profunda Cervicis, 
 br. of the superior intercostal (from the subclavian). 
 
 After Ligature of the Subclavian in its first part, the Collateral Circu- 
 lation is carried on by the following anastomoses: i, that between the 
 Superior and Inferior Thyroid arteries (see above); 2, that between the two 
 Vertebrals; 3, that between the Internal Mammary, the Deep Epigastric 
 and the Aortic Intercostals; 4, the Superior Intercostal with the Aortic 
 
ARTERIAL SYSTEM TABULATED 147 
 
 Intercoslals; 5, the Profunda Cervicis with the Princeps Cervicis; 6, the 
 Scapular branches of the thyroid axis with branches of the Axillary; 7, 
 the Thoracic branches of the Axillary with the Aortic Intercostals. 
 
 TABLES AND PLATES 
 
 OF THE 
 
 ARTERIAL SYSTEM 
 
 NOTE. The arteries in the following plates should be colored red, by painting 
 them over with ordinary crimson ink, or water-color paint, using a fine camel's- 
 hair brush for the purpose. 
 
 Figures in parentheses in these tables refer to the number of another table, thus 
 Ext. Carotid (3) means Table No. 3 of the External Carotid Artery. 
 
 THE ARTERIAL SYSTEM 
 
 i. .1 Numerous branches through- 
 
 Pulmonary Artery. ^ p^Zv' A R T Pat 3 f Ut " PU ' m nary 
 (Plate i.) 3) J carrying venous blood. 
 
HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 R. CORONARY 1 
 
 2. 
 
 Arch of Aorta. 
 (Plate i.) 
 
 L. CORONARY J 
 
 INNOMINATE 
 
 to the muscular tissue of the heart. 
 
 R. COMMON CAROTID 
 
 R. SUBCLAVIAN 
 [ becomes Axillary 
 
 (8) 
 
 Ext. Carotid (3). 
 Int. Carotid (4). 
 Vertebral (5). 
 Thyroid Axis (6). 
 Int. Mammary (7). 
 Sup. Intercostal. 
 
 L. COMMON CAROTID, . . Same as R. Common Carotid. 
 L. SUBCLAVIAN, . . Same as R., continuing as Axillary (8). 
 
 External Carotid. 
 (Plate i.) 
 
 Superior 
 
 Thyroid. 
 
 Lingual 
 
 Submental 
 
 Facial or Ex- 
 ternal Max- 
 illary. 
 
 Muscular and Glandular branches. 
 Hyoid, along lower border of os hyoides. 
 Superf. Descending, crosses Com. Carotid. 
 Sup. Laryngeal, to larynx and epiglottis. 
 Crico-thyroid, crosses Crico-thyroid membrane. 
 
 ( Hyoid, along upper border of bone. 
 
 I Dorsalis Linguae, to tongue, tonsil, palate, etc. 
 
 I Sublingual, to gland, mouth, gums. 
 
 ( Ranine, under surface of tongue, to tip. 
 
 Inf. (Asc.) Palatine, to soft palate and tonsil. 
 Tonsillar, to tonsil and root of tongue. 
 Submandibular, to gland, skin, muscles. 
 
 Superf. Br. anas. inf. labial. 
 
 Deep Br. to the lip. 
 Muscular, to pterygoid, masseter, buccinator. 
 Inf. Labial, anas, with br. of ?th and sth N. 
 Inf. Coronary or labial, anas, with br. of inf. 
 
 dental art. 
 Sup. Coronary, f Art. of Septum Nasi. 
 
 or labial. \ Br. to ala of nose. 
 
 Lateralis Nasi, to ala and dorsum of nose. 
 A ngular, termination of facial trunk. 
 
 Muscular, to digastric, stylo-hyoid, etc. 
 Sterno-mastoid, to that muscle. 
 Auricular, to back part of concha. 
 
 Occipital ( Inf. Meningeal, to dura mater in post, fossa. 
 
 Superf. Br. anas, superf. 
 
 cervical, of trans, colli. 
 
 Princeps Cervicis \ Deep Br. anas, vertebral, 
 and deep cerv. br of 
 sup. intercostal. 
 
ARTERIES OF THE HEAD AND NECK. 
 
 Plate 
 
 ' i 
 
 GOHTINUED 
 
 Potter, del.. 
 
 T4Q 
 
150 
 
 HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 Post. A uricular. . 
 
 Branches (small), to muscles and glands. 
 Stylo-mastoid, to tympanum, mastoid cells, etc. 
 Auricular, to cartilage of ear. 
 Mastoid, to scalp above ear. 
 
 j Prevertebral, brs. to muscles and nerves. 
 
 Ascending I Tympanic, to inner wall of tympanum. 
 
 Pharyngeal. ] Meningeal Branches, to dura mater. 
 
 [ Pharyngeal Branches, 3 or 4 in number. 
 
 3- 
 
 Superficial 
 
 External 
 
 Temporal. 
 
 Carotid. 
 
 
 (Contin- 
 
 
 ued.) 
 
 
 
 INTERNAL 
 
 i. 
 
 
 MAXILLARY. 
 
 
 
 Divisions: 
 
 
 
 i. Maxillary. 
 
 
 
 2. Pterygoid. 
 
 
 
 3. Spheno- 
 
 
 
 maxillary. 
 
 
 Transverse Facial, lies on the masseter. 
 Anterior Auricular Branches, to pinna, etc. 
 Middle Temporal, supplies that muscle. 
 Anterior Temporal, to the forehead. 
 Posterior Temporal, along side of head. 
 
 _, . / to memb. tympani, anas, with Stylo- 
 
 j. ympanic\ . , ,. __. -. 
 
 ( mastoid and Vidian arteries. 
 
 Deep Auricular, to outer surface of the mem- 
 brana tympani. 
 
 Mid. Meningeal, to dura and cranial bones. 
 Small or Accessory Meningeal, to dura and Gas- 
 serian gang. 
 
 Inferior Dental L * n * Ual ' to m ' m ' of mouth " 
 I Mylo-hyoid, in that groove. 
 
 M^Tl l T ern " nal Brs - 
 
 Mandibular 
 
 j Deep Temporal, 2, under temporal muscle. 
 I Pterygoid Brs., to pterygoid muscles. 
 I Masseteric to deep surface of masseter. 
 ( Buccal, a small br. to buccinator. 
 
 A Iveolar 
 
 Dental, to molars, bicuspids. 
 Branches, to antrum, gums, etc. 
 
 (several brs. to the orbit. 
 Ant. Dental, to front teeth, an- 
 trum. 
 
 Post. (Desc.) Palatine, to palate, glands, etc. 
 Vidian, to Eustachian tube and pharynx. 
 Ptery go- palatine, to Eustach. tube and pharynx. 
 Artery of Septum, to septum. 
 External Branches 3, to the 
 nares, antrum, ethmoid and 
 sphenoid cells. 
 
 Spheno- palatine 
 
ARTERIAL SYSTEM TABULATED 
 
 THE ARTERIAL SYSTEM. Continued 
 
 
 Tympanic, to tympanum by foramen in carotid canal. 
 
 
 Arteria Receptaculi (several), in cavernous sinus. 
 
 
 Ant. Meningeal, to dura mater of ant. fossa. 
 
 
 
 r Lacrimal, to that gland, lid, etc. 
 
 
 
 Supraorbital, the largest sub-branch. 
 
 
 
 . , ,/ Meningeal, to dura. 
 Post - Eihmotdal \NasalBrs., to nose. 
 
 
 
 i. 
 
 Ant. Ethmoidal, has same branches. 
 
 
 
 
 Sup. Palpebral, arch on margin of lid. 
 
 
 OPHTHALMIC. 
 
 
 Inf. Palpebral, margin of lower lid. 
 
 
 Groups: 
 
 
 Frontal, to muscles, skin 1 
 
 
 i. Orbital. 
 
 
 / Transverse, [Terminal Branches. 
 
 4. 
 
 2. Ocular. 
 
 * \DorsolisNasi. J 
 
 Internal 
 
 (Plate 4. 
 
 
 Carotid. 
 
 Pig. 2.) 
 
 
 Art. Centralis Retina, to the retina. 
 
 (Plate i.) 
 
 
 
 ( Ant. Ciliary, to the iris. 
 
 
 
 
 Muscular \ Superior, to ocular muscles. 
 
 
 
 2. ' 
 
 [ Inferior, to ocular muscles. 
 
 
 
 
 Short Ciliary, 6 to 12, around optic n. 
 
 
 
 Long Ciliary 2, to circles on iris. 
 
 A nlerior Cerebral 
 
 ( Ant. Communicating, 2 lines long. 
 ' ' \ Ganglionic and Frontal branches. 
 
 Middle Cerebral 
 
 / Ganglionic, Frontal, Parietal, and Parieto- 
 
 \ temporal branches. 
 Posterior Communicating, 
 
 anas, with Post. Cerebral of Basilar, to 
 
 form the Circle of Willis. 
 Anterior Choroid, to the choroid plexus, etc. 
 
 BASILAR 
 
 Post. Cerebral Post. Commun. 
 
 THE CIRCLE OF WILLIS 
 
 I ^ TERNAL 
 CAROTID. 
 
 Ant. Cerebral 
 
 ral \ 
 
 Post. Cerebral Post. Commun. 
 
 Ant ' Cerebral 
 
 Ant. 
 Commun. 
 
152 
 
 HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 s. 
 
 VERTEBRAL 
 (Plate i.) 
 
 Lateral Spinal 
 
 Anterior Spinal 
 
 Br. to spinal cord and membranes. 
 Br. to bodies of Vertebras posteriorly. 
 Muscular Branches, to deep cervical muscles. 
 Post. Meningeal, ramify between dura mater and skull. 
 
 joins its fellow to form Ant. Median Artery of the 
 
 spinal cord. 
 Posterior Spinal, to spinal cord and membranes, laterally. 
 
 / Internal \ to cerebellum, and choroid plexus 
 Post. Inf. Cerebellar s _ , > ,, .v-ir^-i 
 
 ( External J of the 4th Ventricle. 
 
 Bulbar, minute branches to the medulla oblongata. 
 
 / to Pons Varolii, etc. 
 Transverse s T . ,. , . 
 
 ( Int. Auditory, to that canal. 
 
 , /to the cerebellum, anas, with post. 
 Ant. Inf. Cerebellar \ . , ... f ,, . , . 
 
 ( inf. cerebellar of Vertebral. 
 
 Superior Cerebellar, to pia mater, pineal gland, etc. 
 
 Post. Choroid, to choroid plexus 
 Ganglionic, to post, lobes. 
 
 Posterior Cerebral { Ant. Temporal, 
 
 n m I terminal 
 
 Post. Temporal, } , 
 
 _ . . . branches. 
 
 Occipital, 
 
 Inf. Laryngeal, to post, muscles of larynx. 
 Tracheal Brs. to trachea, anas. Bronchial. 
 (Esophageal Brs. to oesophagus. 
 Ascending Cervical, to muscles, spinal cord. 
 Muscular, to muscles of hyoid bone and of the 
 
 pharynx. 
 
 Superficial Cervical, beneath Trapezius. 
 Posterior Scapular, along post, border. 
 Supra-acromial, anas. Acromial Thoracic. 
 Supra-scapular. . . . I Supra-sternal, to skin of the chest. 
 1 Muscular, to sterno-mastoid, etc. 
 I Nutrient, to the clavicle. 
 
 6. 
 
 THYROID 
 Axis. 
 (Plate i.) 
 
 Inferior Thyroid. 
 
 Transversalis Colli. 
 
 Comes Nervi Phrenici (Superior Phrenic), to Diaphragm. 
 Mediastinal Brs. to tissue and glands, ant. mediastinum. 
 Pericardiac Brs. to upper part of pericardium. 
 Sternal Brs. to sternum and Triangularis sterni. 
 INTERNAL Anterior Intercostals, to 5 or 6 upper intercostal spaces. 
 MAMMARY. Perforating, to Pectoralis major, mammary gland, etc. 
 (Plate i.) *..,..! ^i.^ a ^;^ / Ant. Intercostals, to lower intercostal spaces. 
 Brs. to lower pericardium, Diaphragm, etc. 
 f anas, with deep Epigastric of Ext. Iliac. 
 \ supplies abdominal muscles and skin. 
 
 Musculo-phrenic 
 Superior Epigastric 
 
ARTERIAL SYSTEM TABULATED 
 
 Axillary. 
 
 (Plate 2.) 
 i from ist part, 
 i " 2d " 
 3 " 3d " 
 
 THE ARTERIAL SYSTEM. Continued 
 
 j Superior Thoracic, to Pectoral muscles and wall of thorax. 
 
 ( Brs. to Pectorals and Deltoid. 
 [ Acromio Thoracic -| Descending, to both these muscles. 
 
 [ Clavicular, to the Subclavius. 
 
 ( Alar Thoracic, to glands of axilla. 
 
 \ Long Thoracic, to Serratus, Pectorals and glands. 
 
 Subscapular 
 
 A nterior Circumflex 
 
 [ Subscapular. 
 Dorsalis Scapulce \ Infra-spinous. 
 
 { Median. 
 Main trunk to inf. angle of the scapula. 
 
 f around neck of humerus, to Deltoid. 
 1 Br. to shoulder-joint. 
 
 Posterior Circumflex 
 
 \ around neck of humerus, to Deltoid 
 \ muscle and shoulder-joint. 
 
 Becomes BRACHIAL (10), at lower margin of tendon of the Teres major 
 muscle. 
 
 (Post. Articular, to elbow-joint anastomosis 
 and inner side of arm. 
 Main trunk, in spiral groove of the hu, 
 merus, to Deltoid, Triceps, etc. 
 
 9. Nutrient, to nutrient canal of the humerus. 
 
 Brachial. Inferior Profunda (sup. uln. collat.) to the elbow-joint anastomosis. 
 (Plate 2.) Anastomotica Magna (inf. uln. collat.), transversely inward on 
 
 Brachialis anticus muscles to the elbow, where it anastomoses 
 with several arteries. 
 
 Muscular, 3 or 4, to muscles in course of artery. 
 Bifurcates into RADIAL (10) and ULNAR (n). 
 
 ( Radial Recurrent, anas, branches of Sup. profunda. 
 J Muscular Brs. to muscles on radial side of arm. 
 
 Ant. Carpal, to wrist-joints, anas. Ant. Carpal of Ulnar. 
 
 Superficialis Voice, to muscles of the thumb. 
 
 Post. Carpal 
 
 to wrist-joints, anas. Post. Carpal of Ulnar. 
 
 Dorsal Interosseous, for 3d and 4th spaces. 
 Metacarpal, is the First Dorsal Interosseous Branch. 
 Dor sales Pollicis 2, laterally on dorsum of thumb. 
 Dorsalis Indicts, on radial side of index dorsum. 
 
 10. 
 Radial. 
 
 (Plate 2.) 2. 
 
 1. In forearm. 
 
 2. In wrist. 
 
 3. In hand. 
 
 Princeps Pollicis, 2 Brs. forming arch on last phalanx. 
 Radialis Indicts, along radial side of index ringer. 
 Perforating 3 between heads of last Dorsal Interossei. 
 
 / 3 or 4 along Interossei muscles, given 
 Palmar Interossea{ - . %> 1 
 
 \ off by Deep Palmar Arch. 
 
 Palmar Recurrent, to the carpal articulations. 
 
 Forms DEEP PALMAR ARCH in the hand, completed by inosculation with 
 the Deep Palmar (Communicating) from the Ulnar Artery. 
 
154 
 
 HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 Anterior Ulnar Recurrent, ascends in front of inner condyle 
 Posterior Ulnar Recurrent, ascends behind inner condyle. 
 
 pierces Interosseous mem- 
 brane, descending to back 
 of wrist. 
 
 Anterior Muscular Branches. 
 Interosseous Nutrient, of both bones. 
 
 Br. on Pronator quadratus. 
 Interosseous \ [ Median, along median n. 
 
 11. 
 Ulnar. 
 
 (Plate 2.) 
 
 1. In forearm. 
 
 2. In wrist. 
 
 3. In hand. 
 
 3. 
 
 Posterior 
 Interosseous 
 
 to back of wrist. 
 Interosseous Recurrent, to 
 elbow-joint anastomosis. 
 Muscular, to muscles on ulnar side of arm. 
 
 Anterior Carpal, to joints, anas. Carpal of Radial. 
 
 | to joints of wrist, anas. Carpal of Radial. 
 Posterior Carpal j forming the Post. Carpal Arch. 
 
 [ Metacarpal, to little finger. 
 
 !anas. with termination of Radial 
 Artery, completing the Deep 
 Palmar Arch. 
 
 from convexity of Superf. Palmar Arch, to the 
 sides of the fingers, except the radial side of 
 the index finger and thumb (supplied from 
 the radial). 
 
 Digital 4 
 
 Forms SUPERFICIAL PALMAR ARCH in palm of hand, by inosculating with 
 a branch from the Radialis Indicis of the Radial Artery. 
 
 Pericardiac Branches, distributed to the pericardium. 
 Bronchial Arteries 3 nutrient vessels of the lungs. 
 
 12. (Esophageal, 4 or 5, anas. brs. Inf. Thyroid, Phrenic, Gastric. 
 
 Thoracic ^ Posterior Mediastinal, (several) to glands, etc., in mediastinum. 
 
 Aorta. I Posterior (Dorsal), to muscles of back. 
 
 (Plate 3). Intercostals. I Spinal, to the spinal cord and its membranes. 
 
 1 8. | Collateral Intercostal, along upper border of the 
 
 1 next rib below. 
 
ARTERIES OF THE 
 UPPER EXTREMITY. 
 
 \ 
 
 Potter del 
 
156 
 
 HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 
 l Internal, to front of thorax and Diaphragm. 
 
 
 Phrenic | External, to side of thorax. 
 
 
 
 to cardiac orifice of stomach, cardiac end. 
 
 
 - rin rfW f t 
 
 then along lesser curvature to pylorus, 
 
 
 
 
 where it anas, with Pyloric Br. of Hepatic 
 
 
 
 
 Art. 
 
 
 
 
 Pyloric, to pylorus, anas. Gastric Art. 
 
 
 
 
 f Gastro-epiploica 
 
 
 
 
 \ Dextra 
 
 
 
 
 Gastro-duodenalis < D * , 
 Pancreatico-duo- 
 
 
 CcELIAC 
 
 
 { denalis Superior. 
 
 
 Axis. 
 
 Hepatic 
 
 
 
 
 
 TT ) to right lobe. 
 Right Hepatic, < -, 
 \ Cystic, to gall-bladder. 
 
 
 
 
 Left Hepatic, to left lobe of liver. 
 
 
 
 
 Pancreaticce Parva \ 
 
 
 
 
 > to the pancreas. 
 Pancreatic Magna ) 
 
 
 
 Splenic 
 
 Gastric Vasa Brevia, 5 to 7, to the greater 
 
 
 
 or 
 
 curvature of stomach. 
 
 
 
 Lienal 
 
 Gastro-epiploica Sinistra, along the greater 
 
 
 
 curvature, from left to right. 
 
 
 
 Terminal Brs. enter hilum of Spleen. 
 
 13- 
 
 
 Inferior Pancreatico-duodenal, to those organs. 
 
 Abdominal 
 
 
 Vasa Intestini Tenuis 12 to 15, form arches in mesen- 
 
 Aorta. 
 
 
 tery, in several series, from terminal arches branches 
 
 (Plate 3.) 
 
 
 ramify on intestines. 
 
 
 Superior 
 Mesenteric. 
 
 / Inferior, anas. Vasa intes. ten. 
 Ileo-colic < . .. , , 
 ^ Superior, anas. Colica dextra. 
 
 
 
 / Desc. Br. \ Arches branching to ascend- 
 Cohca Dextra \ . _ > . 
 1 Asc. Br. ) ing colon. 
 
 
 
 / Right \ Arches, branching to trans- 
 Colica Media < _ * > . 
 \ Left ) verse colon. 
 
 
 Supra-renal, to supra-renal capsule. 
 
 
 . / Brs. to substance of kidney. 
 Renal \ 
 
 
 { Small Brs. to capsule, ureter, etc. 
 
 
 Spermatic (or Ovarian) to testes or ovaries, uterus, etc. 
 
 
 Inferior 
 
 (Asc. \ Arches branching to descend- 
 Colica Sinistra < ^ V 
 [ Desc. J ing colon. 
 
 
 Mesenteric. 
 
 Sigmoid, across Psoas to that flexure of colon. 
 
 
 (Plate A } 
 
 ( KY tn ricrlit 1 
 
 
 ^i late 4v 
 
 Sup. Hemorrhoidal, < ' ^ > side of rectum. 
 
 
 
 to muscles, etc., of back. 
 Spinal, to canal s ' \ Arches. 
 
 Abdominal, between abdominal muscles. 
 Middle Sacral, to coccyx, anas. Lateral Sacral. 
 
 / RIGHT COM. ILIAC, R. Int. and Ext. Iliac (14, 15). 
 
 Bifu.rc3.t6S s 
 
 Bifurcation occurs at 4th Lumbar Vertebra, opposite Umbilicus. 
 
BRANCHES OF THE AORTA 
 
 Plate 3. 
 
 Potter.del 
 
 157 
 
HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 Superior Vesical 
 
 Obturator. 
 
 \ Art. of Vas Defer ens, to that organ. 
 \ Middle Vesical, to base of bladder. 
 
 14 a. 
 Internal Iliac or 
 
 Uterine, < 
 
 Hypogastric. , 
 
 I 
 
 ANTERIOR 
 
 Vaginal, analog 
 
 TRUNK. 
 
 
 (Plate 4.) 
 
 
 
 Internal 
 
 
 Pudic, or 
 
 
 Pudendal. 
 
 
 Sciatic or 
 
 
 Inf. Gluteal. 
 
 Iliac, to iliac bone and Iliacus muscle. 
 
 Vesical, backward to the bladder. 
 
 Pubic, on the back of the pubic bone. 
 
 Internal, along inner margin obturator foramen. 
 
 External / outer mar g m obturator foramen. 
 
 \ Br. to hip-joint by cotyloid notch. 
 Inferior Vesical, to base of bladder, prostate gland, etc. 
 Middle Hemorrhoidal, to anus, anas, other hem. arteries, 
 f Br. to the bladder. ] 
 
 Br. to the ureter. 
 
 Cervical, to neck of uterus. 
 
 Azygos, of the vagina. 
 
 In the female. 
 
 Inferior Hemorrhoidal, 2 or 3 to the anus. 
 Superficial Perinaal, to the scrotum, etc. 
 Transverse Perinceal, to muscle of same name. 
 Artery of the Bulb, large but very short. 
 Artery of the Corpus Cavernosum, to that body. 
 Dorsal Artery of the Penis, or clitoris. 
 
 Muscular Brs. within the pelvis. 
 Hemorrhoidal Brs. to the rectum. 
 Vesical Brs. to base and neck of bladder. 
 Coccygeal, to back of coccyx. 
 Inf. Gluteal 3 or 4, to Gluteus maximus. 
 Comes Nervi Ischiadici, along sciatic nerve. 
 Muscular Brs. to back of hip. 
 Anastomotic, to the crucial anastomosis. 
 Articular Brs. to capsule of the hip- joint. 
 
ARTERIES or THE PELVIS AND THIGH. Plate 4 
 
 FIG. 2 
 
 BRANCHES Ot OPHTHALMIC ARTtRY. 
 
 Potter .del 
 
 159 
 
i6o 
 
 HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 14 b. 
 
 Internal Iliac or 
 
 Hypogastric. 
 
 POSTERIOR 
 
 TRUNK. 
 
 (Plate 4.) 
 
 Ilio-lumbar, 
 
 Iliac, to Iliacus internus and Ilium. 
 
 / to Psoas and Quad, lumborum. 
 
 Lumbar, 
 
 \ Spinal Br. to cord and membranes. 
 
 Superior Lateral Sacral, to dorsum of sacrum. 
 Inferior Lateral Sacral, to front of sacrum, and coccyx, anas 
 with Sacra media, etc. 
 
 Gluteal, 
 
 Muscular Brs. within the pelvis. 
 
 Nutrient, of the Ilium. 
 
 Superficial, to Gluteus maximus, etc. 
 
 Superior, to ant. sup. spine of Ilium. 
 
 Inferior, to glutei and hip-joint. 
 
 Deep 
 
 Muscular Brs. several, to Psoas and glands. 
 
 15. [ Cremasteric, to cremaster muscle. 
 
 External Iliac. Epigastric, -I Pubic, to inner side of femoral ring. 
 
 (Plate 4.) ( Muscular, to abdominal muscles and skin. 
 
 . ,, rf . \ between Transversalis and Int. oblique. 
 Circumflex Iliac, < _ . . T , , _ . . 
 
 ( Br. anas, with Lumbar and Epigastric. 
 
 Becomes FEMORAL (16) at Poupart's Ligament. 
 
 Superficial Epigastric, in superf. fascia, to umbilicus. 
 
 Superf. Circumflex Iliac, outward to iliac crest. 
 
 Superf. Ext. Pudic (pudendal) , inward to skin of penis, scrotum 
 
 etc. 
 Deep Ext. Pudic (pudendal), inward to skin of perineum, etc. 
 
 Asc. Brs. outer side of hip. 
 Ext. Circumflex, { Transverse, to back of hip. 
 Descending, as far as knee. 
 
 16. 
 Femoral. 
 
 (Plate 4.) 
 
 Profunda 
 Femoris, 
 
 I Ascending, to Adductors, etc. 
 Int. Circumflex, -j Descending, to Adductors, etc. 
 
 [ Articular, to head of femur, 
 f Superior, pierces Adductor magnus. 
 
 Perforating,^, Middle, < Nutrient of Femur. 
 
 { Inferior, pierces Adductor magnus. 
 
 Muscular 2 to 7, along artery, to Sartorius, Vastus internus, etc. 
 
 j Superficial Br. to integument. 
 
 Anastomotica Magna,} Deep Br. to inner side of knee and joint, 
 or Genu Suprema. anas, with Sup. Articulars and Recur- 
 
 [ rent br. of Anterior Tibial. 
 Becomes POPLITEAL (17), at opening in Adductor magnus. 
 
ARTERIES OF THE LEG. | 
 
 Plate 5 
 
 Potter.dei 
 
 II 
 
 161 
 
HUMAN ANATOMY 
 
 THE ARTERIAL SYSTEM. Continued 
 
 17- 
 Popliteal. 
 
 (Plate 4.) 
 
 Muscular 
 
 / Superior Brs. to Vastus ext. and flexor muscles. 
 
 \ Inferior or Sural 2, to Gastrocnemius and Plantaris. 
 Cutaneous Brs. to integument of calf. 
 Superior Internal Articular, to Vastus int. and joint. 
 Superior External Articular, to Vastus ext. and joint. 
 Azygos Articular, to synovial membrane of joint. 
 Inferior Internal Articular, to head of tibia and joint. 
 Inferior External Articular, to front of knee-joint. 
 
 . , / ANTERIOR TIBIAL (i 8) \at lower border of Popliteus 
 Bifurcates into | p OSTERIOR TlBIAL (lp) | musde 
 
 Post. Recurrent Tibial, to the Popliteus muscle. 
 Superior Fibular, to the Soleus and Peroneus longus. 
 Ant. Recurrent Tibial, to the knee-joint anastomosis. 
 18. Muscular Brs. numerous to muscles of leg. 
 
 Anterior I Internal Malleolar, beneath tendon of Tibialis anticus. 
 
 Tibial. j External Malleolar, to outer ankle. 
 
 (Plate 5.) Tar sal, to tarsal joints and Ext. brev. digit. 
 
 7 Digital 
 branches. 
 
 Dorsalis Pedis 
 
 Metatarsal, < 3 Interossea, 
 
 Dorsalis Hallucis 
 
 Communicating, 
 
 Ends in the PLANTAR ARCH. 
 
 Brs. to great toe. 
 Br. to inner side of 2d toe. 
 anas. Ext. Plantar (Arch). 
 2 Digital Brs. 
 
 Peroneal, 
 
 Anterior Peroneal, pierces interosseous membrane. 
 Posterior Peroneal, to the os calcis. 
 Nutrient* Artery of the fibula. 
 Muscular, several brs. in its course. 
 
 / joins similar branch of the poste- 
 Commumcating { 
 
 \ nor Tibial. 
 
 Ext. Calcanean, the terminal branches. 
 19. Muscular, to Soleus, etc., on back of leg. 
 
 Posterior I Nutrient of Tibia, the largest nutrient artery of bone. 
 
 Tibial. Communicating Br. to a similar br. of the Peroneal. 
 (Plate 5.) Internal Calcanean Brs. to the heel, and sole of foot. 
 
 Internal Plantar, along inner side of foot and great toe. 
 ( Brs. to muscles, fascia and skin. 
 Posterior Perforating 3 Branches. 
 
 4 Digital, { Ant. Perforating Branches. 
 k I 
 
 Ends as the PLANTAR ARCH, anas, with Commun. Br. of Dorsalis Pedis. 
 
 External Plantar, 
 
THE VEINS 163 
 
 THE VEINS 
 
 Veins are vessels which return the blood from the capillaries of the body 
 to the heart. Their walls, like those of the arteries, are composed of 3 
 coats an internal serous (tunica intima), a middle muscular (tunica 
 media), and an external one (tunica externa or adventitia) of connective 
 tissue. Their middle coat is weaker than that of the arteries, so that they 
 do not stand open when divided, as the arteries do. They all carry carbon- 
 ized (venous) blood, except the pulmonary veins, which bring oxygenated 
 blood to the left side of the heart. The deep veins accompany the arteries, 
 generally in the same sheath, and are given the same names. The second- 
 ary arteries, as the radial, ulnar, brachial, etc., have each two veins, called 
 Vena Comites. The superficial veins are usually unaccompanied by 
 arteries, and lie, as a rule, between the layers of the superficial fascia, 
 terminating in the deep veins. Many veins are so irregular in their 
 origin that they cannot be accurately described; they all anastomose with 
 each other much more freely than do the arteries. 
 
 Venous Sinuses are venous channels, differing from veins in structure, 
 but answering the same purpose. Those of the cranium are formed by 
 the separation of the layers of the dura mater. 
 
 The Veins are divided into the Pulmonary, Systemic, and Portal Sys- 
 tems; the latter being an appendage of the systemic, its capillaries ramify- 
 ing in the liver. 
 
 Veins having no valves are the venae cavae, hepatic, portal, renal, 
 uterine, ovarian, cerebral, spinal, pulmonary, umbilical, and the very small 
 veins. 
 
 The Pulmonary Veins alone of the veins carry arterial blood, beginning 
 in the capillaries of the lungs, forming a single trunk for each lobule, which, 
 uniting into a single trunk for each lobe, form two main trunks from each 
 lung which open separately into the left auricle. Sometimes the three lobe- 
 trunks of the right lung remain separate to their termination in the auricle, 
 and not infrequently a common opening serves for the two left pulmonary 
 veins. 
 
 VEINS OF THE HEAD AND NECK 
 
 Exterior Veins of the Head and Face are as follows, 
 Frontal Vein, begins on the anterior part of the skull by a venous plexus 
 
 converging to a single trunk near the middle line of the forehead, which 
 
 joins the supra-orbital vein at the root of the nose to form the angular 
 
 vein. 
 Supra-orbital Vein, begins on the forehead and joins the frontal (see 
 
 above) to form the angular vein. 
 
1 64 HUMAN ANATOMY 
 
 Angular Vein, formed as described above, runs downward and outward 
 on the side of the root of the nose, communicates with the ophthalmic 
 vein, and ends in the 
 
 Facial Vein, a direct continuation of the angular, begins at the side of the 
 root of the nose, descends obliquely across the masseter muscle and 
 over the body of the lower jaw to unite with the ant. division of the 
 temporo-maxillary to form the common facial vein, which enters the 
 internal jugular. 
 
 Temporal Vein, begins on the vertex and side of the skull, by anterior and 
 posterior branches which unite and are joined by the middle temporal 
 above the zygoma to form the trunk, which descends through the parotid 
 gland and unites with the internal maxillary to form the temporo- 
 maxillary vein. 
 
 Internal Maxillary Vein, is formed by branches corresponding to those of 
 the internal maxillary artery, forming the pterygoid plexus. The trunk 
 passes backward behind the neck of the lower jaw and unites with the 
 temporal to form the 
 
 Temporo-maxillary Vein, descends in the parotid gland and divides into 
 an anterior branch, which joins the facial, and a posterior branch which 
 is joined by the posterior auricular and becomes the external jugular. 
 
 Posterior Auricular Vein, begins on the side of the head, descends behind 
 the external ear and joins the posterior division of the temporo-maxillary, 
 forming the external jugular. 
 
 Occipital Veins, begin in a plexus at the back of the head and terminate 
 in the internal jugular. 
 
 Veins of the Diploe and Interior of the Cranium, 
 
 - Veins of the Diploe, a number of tortuous canals lying between the two 
 tables of the skull, and divided into frontal (empties into supra-orbital), 
 anterior temporal (empties into either the spheno-parietal sinus or ante- 
 rior deep temporal), posterior temporal and occipital branches which 
 empty into either the occipital vein or the lateral sinus (sinus 
 transversus) .^ 
 
 Cerebral Veins, have no muscular coat and no valves. They are divided 
 into superficial and deep sets. The deep cerebral are formed by the 
 union of the vena cor ports striati (vena terminalis) and the choroid vein 
 on either side, and receive the basilar vein, forming the great cerebral 
 vein (veins of Galen). 
 
 Ccrcbcllar Veins, on the surface of the cerebellum, are disposed in 3 sets, 
 superior, inferior and lateral. 
 
 Superior Longitudinal Sinus (sinus longitudinalis vel sinus sagittalis 
 
DURAL SINUSES 165 
 
 superior), occupies the attached margin of the falx cerebri, begins at 
 
 the foramen caecum, and ends in the torcular Herophili (confluens 
 
 sinuum), or confluence of the sinuses. 
 Inferior. Longitudinal Sinus (sinus sagittalis inferior), in the free margin 
 
 of the falx cerebri posteriorly, terminates in the 
 Straight Sinus (sinus rectus or tentorial sinus), at the junction of the falx 
 
 cerebri with the tentorium, terminates in the lateral sinus (sinus trans- 
 
 versus) of the opposite side. 
 
 Lateral Sinuses (sinus transversi), in the attached margin of the ten- 
 torium cerebelli, terminate in the internal jugular vein. 
 ,~" Occipital Sinuses (sinus occipital es), in the attached margin of the falx 
 
 cerebri, terminate in the torcular Herophili. 
 Cavernous Sinuses (sinus cavernosi), one on each side of the sella turcica, 
 
 receive the ophthalmic vein and open behind into the petrosal sinuses. 
 Circular Sinus (sinus circularis), is formed by two transverse vessels, the 
 
 anterior and posterior intercavernous sinuses, connecting the two 
 
 cavernous sinuses, and forming a venous circle around the pituitary 
 
 body. 
 Superior Petrosal Sinus, connects together the cavernous and lateral 
 
 sinuses of each side. 
 Inferior Petrosal Sinus, begins at the termination of the cavernous sinus, 
 
 and joins the lateral sinus to form the internal jugular vein. 
 Transverse or Basilar Sinus (plexus basilaris], connects the two inferior 
 
 petrosal sinuses over the basilar process of the occipital bone. 
 Emissary Veins (emissaria), pass through apertures in the cranial wall 
 
 from the sinuses inside to the veins outside; the principal ones being 8 
 
 in number. 
 
 1. Frontal through foramen caecum. 
 
 2. Parietal (two) through parietal foramina. 
 
 .3. Occipital through foramen in occipital protuberance (occasional). 
 
 4. Post-condylar (condyloid) through foramen behind occipital condyle. 
 
 5. Emissary plexus through foramen ovale. 
 
 6. Vein of Vesalius through foramen of Vesalius. 
 
 7. Plexus through internal carotid canal. 
 
 8. Plexus through anterior condylar canal (hypoglossal canal). 
 
 Veins of the Neck, draining those above-mentioned, are the 
 External Jugular (6), terminating in the subclavian vein (4). 
 Posterior External Jugular, opens into the external jugular. 
 Anterior Jugular (7), enters the subclavian vein near the external jugular. 
 Internal Jugular (5), formed by the junction of the two last-named 
 
i66 
 
 HUMAN ANATOMY 
 
 sinuses at the jugular foramen, and uniting with the subclavian vein to 
 form the innominate, at the root of the neck. In its course it receives 
 the facial, lingual, pharyngeal, superior and middle thyroid veins, and 
 the occipital. 
 
 Vertebral, descends the foramina in the transverse processes of the cervical 
 vertebrae, and empties into the innominate vein. In its course it 
 receives the anterior and posterior vertebral and many other veins. 
 
 VEINS OF THE UPPER EXTREMITY 
 
 Veins of the Hand, Forearm, and Arm are in two sets, superficial and 
 deep. The superficial set lies in the superficial fascia, begin in the hand 
 by external and internal dorsal and superficial galmar veins, and are 
 continued as follows, the basilic continuing as the axillary, which receives 
 the cephalic just below the clavicle. 
 
 Radial (cephalic B.N.A.) ./i^.^ \ f 
 
 . . > Cephalic 
 
 Median Cephalic } 
 
 Profunda 
 Median Basilic 
 
 Dorsal. 
 
 Palmar. 
 
 Dorsal. 
 
 Median (median 
 cubital) 
 
 I Anat. Ulnar 
 ! (basilic B.N.A. 
 | Post. Ulnar 
 { (basilic B.N.A. 
 
 Common Ulnar 
 (basilic B.N.A.) 
 
 Basilic 
 
 AXIL- 
 LARY 
 VEIN. 
 
 The deep veins follow the arteries, generally as venae comites, beginning 
 in the hand as Digital, Interosseous and Palmar veins, they unite in the 
 Deep Radial and Deep Ulnar, which join to form the Vena Comites of 
 the brachial artery at the bend of the elbow. The Brachial Veins lie 
 one on each side of the brachial artery and join the Axillary Vein. These 
 deep veins have numerous anastomoses, not only with each other but also 
 with the superficial ones. 
 
 Axillary Vein (v. axillaris), the continuation of the basilic, lies on 
 the inside of the artery and terminates beneath the clavicle at the 
 outer border of the ist rib, where it becomes the 
 Subclavian Vein (v. subclavia), the continuation of the axillary, 
 extends from the outer border of the ist rib to the inner end of the 
 clavicle, where it unites with the internal jugular to form the in- 
 nominate vein. At the angle of junction enters the thoracic duct on 
 the left side of the body and the right lymphatic duct on the right 
 side. In its course it receives the external and anterior jugular 
 veins and a branch from the cephalic. 
 The Innominate Vein (vena anonyma) is formed by the union of the 
 
VEINS OF THE THORAX 
 
 i6 7 
 
 subclavian and the internal jugular. The two innominates unite just 
 below the ist costal cartilage to form the superior vena cava. The 
 Right Innominate (v. anonyma dextra) (3) is 
 about i inch long, and receives, besides its FIG. 69. 
 
 constituent branches, the right internal mam- 
 mary, right inferior thyroid, and right superior 
 intercostal veins. The Left Innominate (v. 
 anonyma sinistra) (2) is about 2^ inches long; 
 in its course it receives the vertebral, inferior 
 thyroid, internal mammary, and superior inter- 
 costal veins of the left side. 
 
 VKIXS OF THE THORAX 
 
 The Veins of the Thorax include the follow- 
 ing vessels: 
 ,* Internal Mammary, (mamariainterna), two to 
 
 each artery, unite into a single trunk which 
 
 terminates in the innominate vein. 
 Inferior Thyroid (vv. thyreoideae inferiores), 
 
 2 to 4, form a plexus in front of the trachea, 
 
 which gives off the left and right inferior 
 
 thyroid veins, these receiving cesophageal, 
 
 tracheal and inferior laryngeal veins and 
 
 opening into the innominate veins. 
 Superior Intercostal, the right vein (v. inter- 
 
 costalis suprema dextra) opens into the vena 
 
 azygos major, the left vein (v. intercostalis 
 
 suprema sinistra) into the left innominate. 
 Azygos Veins, are described below. 
 * Bronchial, return the blood from the lung 
 
 substance; the right one opens into the vena 
 
 azygos major, the left into the left superior 
 
 intercostal or the left upper azygos vein. 
 Spinal, are described below. 
 Vena Cavce^ are described below; the Superior Vena Cava under the 
 
 Veins of the Thorax, the Inferior Vena Cava under the Veins of the 
 
 Lower Extremity. 
 
 The Azygos Veins supply the place of the venae cavae in the region 
 where these trunks are deficient, being connected with the heart. 
 
 Vena Azygos Major (v. azygos) (17), begins by a branch from the right 
 lumbar veins usually, passes through the aortic opening in the 
 
l68 HUMAN ANATOMY 
 
 diaphragm, and ends in the superior vena cava, having drained 10 
 right lower intercostals, the vena azygos minor, (v. hemiazygos), 
 the right bronchial, cesophageal, mediastinal, and pericardial veins. 
 Left Lower Azygos (vena azygos minor or v. hemiaz3'gos) (18), begins 
 by a branch from the left lumbar or renal, passes through the left 
 crus of the diaphragm, crosses the vertebral column and ends in the 
 right azygos, having drained 4 or 5 lower intercostals. 
 Left Upper Azygas (v. hemiazygos accessoria), drains 3 or 4 left 
 intercostals and empties into either of the other two. It is often 
 wanting, its place being filled by the left superioi intercostal vein (21). 
 The Spinal Veins may be arranged in 4 sets, as follows: 
 Qor si- spinal, form a plexus around the spines, processes, and laminae 
 of all the vertebrae. They empty into the vertebral, intercostal, lumbar, 
 and sacral veins in their respective regions. 
 
 Meningo-rachidian, in two longitudinal plexuses, anterior and posterior, 
 running the whole length of the spinal canal. The posterior join the 
 dorsi-spinal veins, the anterior empty into the vertebral, intercostal, 
 lumbar, and sacral veins in their various regions. 
 
 Vena Basis Vertebrarumthe veins of the bodies of the vertebrae, are 
 contained in large, tortuous channels in the substance of the bones, and 
 join the transverse trunk connecting the anterior longitudinal veins. 
 Medulli-spinale, the veins of the spinal cord, lie in plexus form between 
 the pia mater and arachnoid. They unite into 2 or 3 small trunks near 
 the base of the skull, which terminate in the inferior cerebellar veins 
 or in the inferior petrosal sinuses. 
 
 The Superior Vena Cava (i) is a short trunk about 2^ or 3 inches in 
 length, formed by the union of the two innominate veins, thereby re- 
 ceiving all the blood from the upper half of the body, and opening into the 
 right auricle of the heart. It is half covered by the pericardium, and 
 receives the vena azygos major and small pericardiac and mediastinal 
 veins. 
 
 VEINS OF THE LOWER EXTREMITY 
 
 The Veins of the Lower Extremity are in two sets, superficial and deep. 
 The superficial are the 
 
 Internal or Long Saphenous (saphena magna), on the inside of the 
 leg and thigh, enters the femoral at the saphenous opening i > inch 
 below Poupart's ligament (1. inguinale). In its course it receives: 
 Cutaneous Branches. Superficial Circumflex Iliac. 
 
 Superficial Epigastric. Communicating Branches. 
 
 Ext. Pubic, (venae pudendae externae). 
 
VEINS OF THE PELVIS AND ABDOMEN 1 69 
 
 External or Short Saphenous (v. saphena parva), formed by branches 
 
 from the dorsum and outer side of the foot, it ascends behind the 
 
 outer malleolus, up the middle of the back of the leg, and empties into 
 
 the popliteal vein, between the heads of the gastrocnemius muscle. 
 
 The deep veins are the vence comites of the arteries, beginning in the foot 
 
 as the external (lateral) and internal (medial) Plantar, which unite to form 
 
 the Posterior Tibial (venas tibiales posteriores). The vena comites of 
 
 the dorsalis pedis artery continue upward as the Anterior Tibial veins 
 
 (venae tibiales anteriores), which join the posterior tibial, forming the 
 
 Popliteal, which becomes the Femoral, and it the External Iliac, in 
 
 the same manner as the respectively named arteries. 
 
 VEINS OF THE PELVIS AND ABDOMEN 
 
 The Veins of the Pelvis, except the middle sacral, open into the internal 
 iliac vein. The middle sacral opens into the left common iliac. 
 
 The Internal Hiac Vein (vena hypogastrica) (10) is formed by the 
 venae comites of the branches of the internal iliac artery, and terminates 
 with the external iliac, at the sacro-iliac articulation, to form the common 
 iliac vein (v. iliaca communis). It receives the following veins: 
 From the exterior of the pelvis, the 
 Gluteal, (v. glutaea superior). 
 Sciatic (v. glutaea inferior). 
 Internal Pudic (vv. pudendae internae). 
 Obturator. 
 From the organs in the pelvic cavity the 
 
 Hemorrhoidal Plexus. \ . Uterine Plexus. \ . 
 
 ,, . , J . , > in the male. ,,.,, > in the female. 
 
 Vesico- pro static Plexus. J Vaginal Plexus. J 
 
 The Dorsal Vein of the Penis enters the prostatic plexus. 
 
 The Veins of the Abdomen include the Portal System, the Lumbar, 
 Spermatic, Renal, Suprarenal, Phrenic, Hepatic, External Iliac, Common 
 Iliac and the Inferior Vena Cava. 
 
 The External Iliac Vein commences at the termination of the femoral 
 beneath Poupart's ligament, and terminates opposite the sacro-iliac syn- 
 chondrosis by uniting with the internal iliac to form the common iliac 
 vein. It receives the Deep Epigastric (v. epigastrica inferior) and Deep 
 Circumflex Iliac, also a small pudic vein. 
 
 The Common Iliac Veins (n) are each formed by the union of the two 
 iliac veins as above described, and unite between the 4th and 5th lumbar 
 vertebras to form the inferior vena cava, the right common iliac being the 
 shortest of the two, Each receives the Ilio-lumbar, sometimes the Lateral 
 
1 70 HUMAN ANATOMY 
 
 Sacral, and the left one in addition the Middle Sacral Vein, which some- 
 times ends in the vena cava. 
 
 The Inferior Vena Cava (8) extends from the junction of the two 
 common iliac veins, passing along the front of the spine, through the tendin- 
 ous centre of the diaphragm, to its termination in the right auricle of the 
 heart. It receives the following veins: 
 
 / Lumbar (12), 4 on each side, receive dorsal and abdominal tributaries, 
 also veins from the spinal plexuses, and terminate in the inferior vena 
 cava. They are connected together by the ascending lumbar, which 
 passes in front of the transverse processes of the lumbar vertebrae. 
 ;,, Right Spermatic (13). The spermatic veins arise from the testis and 
 epididymis, forming the spermatic or pampiniform plexus, which forms 
 the chief mass of the spermatic cord, and unite into 3 or 4 veins which 
 enter the abdomen through the internal ring, form 2 veins, then a 
 single one which opens on the right side into the inferior vena cava, on 
 the left side into the left renal vein. In the female they are called 
 Ovarian and terminate in the same way as in the male. 
 ^ Renal (15), are large veins, placed in front of the renal arteries, and 
 terminating in the inferior vena cava. The left is longer than the 
 f right and passes in front of the aorta. 
 
 T Supra-renal, on the right side ends in the vena cava, on the left side in 
 f^ the left renal or phrenic vein. 
 
 Phrenic 2, the superior ends in the internal mammary, the inferior ends 
 oh "the right side in the vena cava, on the left side in the left renal vein. 
 Hj&atic Veins (16), begin in the capillary terminations of the portal 
 vein and hepatic artery in the substance of the liver, uniting into 3 
 large veins from the right and left lobes and the lobulus Spigelii, which 
 open into the inferior vena cava. They have no valves. 
 
 The Portal System is formed by the Superior and Inferior Mesenteric, 
 Splenic, and Gastric Veins, which collect the blood from the digestive vis- 
 cera, and by their union behind the head of the pancreas form the Portal 
 Vein, which enters the transverse fissure of the liver, where it divides into 2 
 branches. These again subdivide, ramifying throughout the organ, 
 therein receiving blood also from the branches of the hepatic artery. 
 Its minute ramifications end in capillaries, from which the blood of the 
 portal system, together with that brought by the hepatic artery, is carried 
 by the hepatic veins to the inferior vena cava. The portal vein generally 
 receives the Cystic Vein, which sometimes terminates in the right branch 
 of the portaT 
 
THE LYMPHATIC SYSTEM 17 1 
 
 VEINS OF THE HEART ITSELF 
 
 The Cardiac Veins return the blood from the tissue of the heart into the 
 right auricle. They are the 
 . Great Cardiac Vein, 
 
 Right or Small Coronary Vein (v. coronaria ventriculi). 
 
 Posterior Cardiac Vein. S Anterior Cardiac Veins. 
 
 Coronary Sinus is a dilatation of the great cardiac vein, receiving the 
 
 Left Cardiac Veins. -^ Ven(B Thebesii. 
 
 Coronary Sinus is a dilatation of the great can 
 * posterior cardiac and an oblique vein from the left auricle. 
 
 THE LYMPHATIC SYSTEM 
 
 Lymphatics are very delicate, transparent vessels; the larger having 3 
 coats like the arteries and veins, the smaller having 2 coats, the external 
 and internal, but no middle muscular-elastic coat. Lymphatics are found 
 in nearly every texture and organ of the body which contains blood- 
 vessels, but are absent in the non-vascular structures, as cartilage, nails, 
 cuticle and hair. They are nourished by blood-vessels distributed to their 
 outer and middle coats, in which also many non-medullated nerve-fibres 
 have been traced. They possess valves of semilunar form, placed at 
 much shorter intervals than are the valves in the veins. They convey 
 lymph to the blood, and possess the property of absorbing certain materials 
 from the tissues and conveying them into the circulation; hence they are 
 also called absorbents. They discharge their contents into the blood at 
 two points, the junctions of the subclavian and internal jugular veins, on 
 the left side by the thoracic duct, on the right side by the right lymphatic 
 duct. 
 
 Lacteals are the lymphatic vessels of the small intestine, conveying chyle 
 to the blood during the process of digestion. 
 
 Lymphatic Glands (lymphoglandulas) are small, solid, glandular bodies, 
 placed in the course of the lymphatic and lacteal vessels, and found 
 chiefly along the great blood-vessels, at the root of the lungs, in the lumbar 
 and cceliac regions of the abdomen, in the mesentery, the mediastina, the 
 head, neck, axilla, groin, and popliteal space. They are named after the 
 respective regions in which they are situated, as axillary glands, the 
 inguinal, cceliac, bronchial, mesenteric, etc. They consist of a fibrous 
 capsule, from which trabecula are prolonged inward, dividing the gland 
 into alveoli or open spaces containing lymphoid tissue, the proper gland- 
 substance, which is so placed as to leave a channel (sinus), the lymph- 
 
172 HUMAN ANATOMY 
 
 path, all around it. The glands are nourished by blood-vessels supported 
 on the trabeculae, and some fine nerve filaments are traced into them. 
 
 Before entering a gland the lymphatic (or lacteal) divides into several 
 small branches, the afferent vessels, of which the endothelial layer only enters 
 the gland, to form in its lymph-sinuses a plexus of vessels which unite into 
 a single efferent vessel. The external coat of the afferent vessels becomes 
 continuous with the capsule of the gland, and is received upon the efferent 
 vessel as it emerges. 
 
 Haemal Lymph Glands, resemble ordinary lymph glands in all respects 
 save that some of their sinuses contain blood. 
 
 Haemal Glands, all of their sinuses contain blood, otherwise they do 
 not differ from regular lymph glands. Both Haemal glands and Haemal 
 Lymph glands are more numerous in the retro-peritoneal tela along the 
 line of the aorta. 
 
 f/ . 3^ The Thoracic Duct (ductus thoracicus) is the main channel for the lymph 
 and chyle from the whole body except the right arm and lung, right side 
 of the head, heart, neck, and thorax, and the convex surface of the liver. 
 It begins in the abdomen by a triangular dilatation, the 
 
 Receptaculum Chyli (cisternachyli), in front of the zd lumbar vertebra, 
 passes through the aortic opening in the diaphragm, and opposite the 7th 
 cervical vertebra it curves forward, outward and downward over the 
 subclavian artery, so as to form an arch, and terminates in the left sub- 
 clavian vein at its angle of junction with the left internal jugular vein. In 
 the thorax it lies in the posterior mediastinum in front of the vertebral 
 column, between the aorta on its left and the vena azygos major on its 
 right. It has numerous valves throughout its course, and a pair of valves 
 at its termination to prevent the passage of venous blood into its cavity. 
 
 The Right Lymphatic Duct (ductus lymphaticus dexter) is a short trunk, 
 about 2^2 inch in length and i% line in diameter. It terminates in the 
 right subclavian vein at its angle of junction with the right internal 
 jugular, its orifice being guarded by two semilunar valves against the 
 passage of venous blood into its cavity. It receives lymph from those 
 parts which are not connected with the thoracic duct, namely the right 
 upper extremity, the right lung, the right side of the head, neck, heart 
 and thorax, and part of the convex surface of the liver. 
 
 LYMPHATICS OF THE HEAD AND NECK 
 
 Lymphatic Glands of the Head and Neck, are as follows: 
 
 Occipital (lymphoglandulae occipitales), i or 2, at the back of the head, 
 close to the artery. 
 
LYMPHATICS OF THE UPPER EXTREMITY 173 
 
 Posterior Auricular or Mastoid (lymphoglandulae auriculares posteriores), 
 
 2, near the mastoid process. 
 Anterior Auricular (lymphoglandulae auriculares anteriores), external to 
 
 the parotid gland. 
 Parotid (lymphoglandulae parotideae), some in and others around the 
 
 parotid gland. 
 
 Buccal, i or more, on the surface of the buccinator muscle. 
 Submandibular (lymphoglandulae submaxillares), beneath the ramus of 
 
 the jaw. 
 Lingual (lymphoglandulae linguales), 2 or 3, on the hyo-glossus and 
 
 genio-hyo-glossus muscles. 
 Retro-pharyngeal (lymphoglandulae retropharyngeae) 2, one on each side 
 
 of the middle line. 
 Superficial Cervical (lymphoglandulae cervicales superficiales), consisting 
 
 of the submaxillary, 8 to 10, the suprahyoid, i or 2, and the cervical 
 
 (many) in the course of the external jugular vein. 
 Deep Cervical (lymphoglandulae cervicales profundae superiores et infe- 
 
 riores), forming a chain along the sheath of the carotid artery and in- 
 ternal jugular vein, in two sets, an upper, 10 to 20, and a lower, 10 
 
 to 15. 
 
 Lymphatic Vessels of the Head and Neck are the/ Temporal and 
 ; Occipital, in the scalp, respectively accompanying the temporal jand oc- 
 cipital arteries; the 'Meningeal an^ Cerebral, in the cranium; the Super- 
 ficial and the Deep, in the face; also those of the orbit, the temporal and 
 zygomatic fossae, the nose, tongue, pharynx, larynx and thyroid body. 
 In the neck these vessels are continuations of those on the cranium and 
 face. 
 
 LYMPHATICS OF THE UPPER EXTREMITY 
 
 Lymphatic Glands of the Upper Extremity (lymphoglandulae cubitales 
 superficiales et profundae) are in two sets, the Superficial, which are few 
 and small, and ih^Deep, in the forearm, the "arm and the axilla. The 
 Axillary Glands, 10 to 12, are of large size, situated around the axillary 
 vessels, in the tissue of the axilla, and in chains along the lower border of 
 the pectoralis major muscle and the lower margin of the posterior wall of 
 the axilla, they are grouped as follows: 
 
 1. Brachial or lateral. 
 
 2. Subscapular or posterior. 
 
 3. Pectoral or anterior. 
 
 4. Central. 
 
 5. Subpectoral. 
 
174 HUMAN ANATOMY 
 
 6. Infraclavicular. 
 
 7. Interpectoral. 
 
 8. Deltopectoral. (Robinson.) 
 
 Lymphatic Vessels of the Upper Extremity are the Superficial, beginning 
 on the sides of the fingers and accompanying the veins; the^Deep, occurring 
 in 4 sets corresponding with the radial, ulnar, and anterior and posterior 
 interosseous arteries. 
 
 LYMPHATICS OF THE LOWER EXTREMITY 
 
 Lymphatic Glands of the Lower Extremity are the -Superficial Inguinal, 
 8 to 10, in two sets, an upper oblique set (lymphoglandulae inguinales) 
 along Poupart's ligament (1. inguinale), and an inferior vertical set (lympho- 
 glandulae subinguinales), 2 to 5, around the saphenous opening in the fascia 
 lata; Deep Glands are the anterior tibial popliteal (lymphoglandulae 
 popliteae), deep inguinal (lymphoglandulae subinguinales profundae), 
 gluteal and ischiatic. 
 
 Lymphatic Vessels of the Lower Extremity are in two sets, superficial 
 and deep. The Superficial lie in the superficial fascia in two groups, an 
 internal and an external, along the internal and external saphenous veins 
 respectively. The Deep are few in number and accompany the deep blood- 
 vessels. 
 
 LYMPHATICS OF THE PELVIS AND ABDOMEN 
 
 Lymphatic Glands are the external iliac, internal iliac, and sacral, in the 
 pelvis; and the lumbar and cceliac glands in the abdomen. The Lumbar 
 Glands are numerous, situated in front of the lumbar vertebrae, and sur- 
 round the common iliac vessels, the aorta and the vena cava. The Cceliac 
 Glands 20, surround the cceliac axis and lie in front of the aorta, receiving 
 the lymphatic vessels from a large part of the liver, the spleen, pancreas 
 and stomach. 
 
 Lymphatic Vessels of the Pelvis and Abdomen are in 3 sets, the super- 
 ficial, the deep, and those of the viscera. The Superficial follow the course 
 of the superficial blood-vessels, and include the lymphatics of the gluteal 
 region, the penis, scrotum and perinaeum. The Deep follow the course of 
 the principal blood-vessels. Those of the Viscera are the lymphatics of 
 the various organs contained in these cavities the bladder, rectum, 
 uterus, kidney, liver, stomach, spleen and pancreas, and include those of 
 the testicles. 
 
 LYMPHATICS OF THE INTESTINES 
 
 Lymphatic Glands of the Intestines are those of the large intestine, 
 which are few in number, especially along the transverse colon; and those 
 
LYMPHATICS OF THE THORAX 175 
 
 of the small intestine, 100 to 150, which lie between the layers of the 
 mesentery and are called the Mesenteric Glands (lymphoglandulae mesen- 
 tericae). 
 
 Lymphatic Vessels of the Intestines are those of the large intestine, 
 some of which enter the mesenteric glands, others the lumbar glands; and 
 those of the small intestine, called the Lacteals, from the milk-white fluid 
 (chyle) which they usually contain. The lacteals are in two sets, super- 
 ficial and deep, the latter occupying the submucous tissue and coursing 
 transversely around the intestine. 
 
 LYMPHATICS OF THE THORAX 
 
 Lymphatic Glands of the Thorax are those of the thoracic walls (lym- 
 phoglandulae sternales et intercostales) and those of the viscera. The 
 former are the intercostal, the internal mammary, and the anterior and 
 posterior mediastinal (lymphoglandulae mediastinales anteriores et 
 posteriores) glands; the latter are the bronchial and the superior medias- 
 tinal or cardiac glands. The 
 
 Bronchial Glands (lymphoglandulae bronchiales), 10 to 12, are situated 
 around the bifurcation of the trachea and the roots of the lungs. 
 
 Superior Mediastinal or Cardiac Glands, are numerous and large, lie in 
 front of the transverse aorta and the left innominate vein, and receive 
 the lymph from the pericardium, the heart, and the thymus gland. 
 
 Lymphatic Vessels of the Thorax are the superficial, the deep and those 
 of the viscera in the thoracic cavity. The Superficial converge to the 
 axillary glands; the Deep are the intercostal, the internal mammary and the 
 diaphragmatic; those of the Viscera are the lymphatic vessels of the lungs, 
 heart, thymus gland and oesophagus. 
 
 THE NERVOUS SYSTEM 
 
 / i. Brain. 
 
 i. Central part < _. . . _ , 
 [ 2. Spinal Cord. 
 
 J i. Cranial Nerves. 
 .. Penpheral part 
 
 " \ 2. Sympathetic System ( '" anglia ' . 
 
 ( 2. Communicating Branches. 
 
 Nervous Tissue is formed of two different structures, viz. Gray or cineri- 
 tious substance, in which nervous impressions and impulses originate; and 
 White or fibrous substance, by which the impressions and impulses are 
 conducted. Chemically, nervous tissue consists of proteids, neurokeratin, 
 
i 7 6 
 
 HUMAN ANATOMY 
 
 nucleiii, protagon, lecithin, cerebrosides, cholesterin, nitrogenous ex- 
 tractives and salts, with some gelatin and fat, and water; the latter varying 
 in different parts of the system, from 60 per cent, in the sciatic nerve, to 
 70 per cent, in the white matter of the cerebrum, and 83 per cent, in the 
 gray matter of the same region. 
 
 Gray Nervous Substance, the essential constituent of all the ganglionic 
 centres, is composed of nerve-cells or ganglionic corpuscles, containing nuclei 
 
 FIG. 70. 
 
 SHOWING SOME OF THE VARIETIES OF THE CELL-BODIES OF THE NEURONES OF 
 THE HUMAN NERVOUS SYSTEM, INCLUDING THE DENDRITES AND SMALLL PORTIONS 
 OF THE AXONES. AxoNE SHEATHS NOT INCLUDED. (Morris' Anatomy.) 
 
 A, From spinal ganglion. B. From ventral horn of spinal cord. C. Pyramidal 
 cell from cerebral cortex. D. Purkinje cell from cerebellar cortex. E. Golgi cell of 
 type II from spinal cord. F. Fusiform cell from cerebral cortex. G. Sympathetic. 
 a, axone; d, dendrites; c, collateral branches; ad, apical dendrites; bd, basal den- 
 drites; c, central process ; p, peripheral process. 
 
 and nucleoli. The cells are imbedded in a ground substance, neuroglia, 
 which consists of fibres and cells, and is a connective tissue in function 
 though not in development. A neurone is a nerve-cell together with all 
 of its processes. Nerve-cells vary in size and shape, and possess one or 
 more processes, according to the number of which they are grouped into 
 unipolar, bipolar and multipolar cells. Of these processes one is called the 
 
THE NERVOUS SYSTEM 177 
 
 axone or axis-cylinder process, because it becomes the axis-cylinder of a 
 nerve- fibre; the others are termed dendrltes or protoplasmic processes. 
 
 White Nerve Substance or Nerve-fibre, contains two kinds of fibres, 
 the medullated or white and the non-medullated or gray. Medullated 
 Fibres contain a central core or axis-cylinder, the essential part of the 
 nerve-fibre, and regarded as a direct prolongation of a nerve-cell. This is 
 surrounded by the medullary sheath, or white substance of Schwann, com- 
 posed of fatty matter in a fluid state, which insulates and protects the 
 axis-cylinder. These are enclosed in the primitive sheath or neurilemma, 
 sometimes called the tubular membrane or sheath of Schwann, which is 
 absent in the fibres found in the brain and spinal cord. A bundle or 
 funiculus, of such fibres, held together by endoneurium, is surrounded by 
 perineurium, both formed of delicate connective tissue; and several funic- 
 uli are collected into larger bundles, fasciculi, which are bound together 
 by a common membrane, the epineurium, and then are called a Nerve, 
 The whole arrangement is precisely analogous to that of a submarine tele- 
 graph cable. The nerve is nourished by a minute system of capillary 
 blood-vessels, and has certain medullated fibres in the epineurium, termed 
 the nervi nervorum, or nerves of the nerves. 
 
 The Non-medullated Fibres, also called gray or gelatinous nerve-fibres, or 
 fibres of Remak, consist of a central core- or axis-cylinder enclosed in a 
 nucleated sheath. They constitute most of the sympathetic nerves and 
 include some of the cerebro-spinal. 
 
 Terminations of Nerves. Their origin or central termination occurs 
 from the nerve centre by one or two roots, in the latter case sometimes 
 widely apart from each other. The efferent nerve-fibres originate in 
 the cells of the gray substance, the afferent fibres branch among the cells 
 without uniting with them. The peripheral termination of sensory nerves 
 seems to be in minute primitive fibrilla or networks thereof; that of motor 
 nerves in special terminal organs, variously named, as the end-bulbs 
 of Krause, the tactile corpuscles of Wagner, the Pacinian corpuscles, 
 the neuro-tendinous and neuro-muscular spindles, and the motorial end- 
 plates of the striped or voluntary muscular fibre. 
 
 Ganglia are separate small aggregations of nerve-cells, connected with 
 each other, with the cerebro-spinal axis, and with nerves in various 
 situations. They consist of a collection of nerve-cells and nerve-fibres, 
 invested by a membranous envelope, which is continuous with the peri- 
 neurium of the nerves, and sends processes into the interior of the ganglion 
 to support the blood-vessels supplying its substance. They are found on 
 the posterior roots of all the spinal nerves, on the posterior (sensory) root 
 12 
 
178 HUMAN ANATOMY 
 
 of the 5th cranial nerve; on the facial, auditory, glosso-pharyngeal and 
 pneumogastric nerves; also in a connected series along each side of the 
 vertebral column anteriorly, forming the trunk of the sympathetic, and 
 on the branches of that nerve. 
 
 THE BRAIN 
 
 Development of the Brain. At an early period of embryonic life the 
 cerebro-spinal axis consists of a thin-walled tube, the neural tube, which, 
 while still open at its caudal end, becomes enlarged at its cephalic end, 
 where constrictions appear, dividing this end into 3 primary vesicles, 
 the anterior, middle and posterior. From these vesicles are developed the 
 ventricles of the brain, the rest of the neural tube forming the central 
 cavity of the spinal cord. Thickenings of the wall of the neural tube 
 form the substance of the brain and spinal cord. The 
 
 Anterior Primary Vesicle, Prosencephalon, divides into an anterior 
 (telencephalon) and a posterior (diencephalon] secondary vesicles. 
 From the telencephalon are developed the cerebral hemispheres; 
 corpora striata; corpus callosum; fornix; lateral ventricles; 
 olfactory lobe; front part of the third ventricle; front part of the 
 tuber cinereum; infundibulum; and the posterior lobe of the pituitary 
 body (hypophysis). From the diencephalon are developed, the optic 
 thalami (thalamus); corpora geniculata (metathalamus) ; pineal 
 body, the posterior part of the tuber cinereum; posterior part 
 of the third ventricle; corpora mammillaria; optic nerve and 
 optic tracts. 
 
 Middle Primary Vesicle, Mesencephalon, its cavity becomes the 
 aqueduct of Sylvius, and with the parts developed around it con- 
 stitutes the mesencephalon or mid-brain. From the mesencephalon 
 are developed, corpora quadrigemina; pedunculi (crura) cerebri; 
 and aquaeductus cerebri (aquaeduct of Sylvius). 
 
 The constricted communication between the middle primary vesicle 
 and the posterior primary vesicle is known as the isthmus rhomben- 
 cephali, from it are developed the superior cerebellar peduncles 
 (brachia conjunctiva) and the valve of Vieussens (anterior medullary 
 velum). 
 
 Posterior Primary Vesicle, Rhombencephalon, by constriction forms 
 an anterior secondary vesicle, metencephalon; and a posterior second- 
 ary vesicle, myelenccphalon. 
 
 From the metencephalon are developed the cerebellum; pons varolii 
 (pons) ; and front part of the fourth ventricle. 
 
THE BRAIN 179 
 
 From the myelencephalon are developed the medulla oblongata and 
 
 the posterior portion of the fourth ventricle. 
 
 Structure of the Cerebrum. The cerebrum is composed of gray and 
 white matter, the former disposed in two great groups, that of the cere- 
 bral cortex and that in the basal ganglia. 
 
 The Gray Matter of the Cortex is composed of 6 alternating white and 
 gray layers. The cortex is made up of nerve-cells and nerve-fibres. The 
 Nerve-cells are arranged in 5 layers, named, from the surface inward, as 
 follows: the fmolecular layer, the outer layer /'.of polymorphous cells, the 
 layer of small pyramidal cells, the layer of large pyramidal cells, the inner 
 layer of polymorphous cells. In certain parts of the cortex this arrange- 
 ment is variously departed from, as many as 9 layers being described in 
 the cuneus. The Nerve-fibres are either medullated fibres or naked axis- 
 cylinders embedded in a matrix of neuroglia. 
 
 The Basal Ganglia are a series of gang! ionic masses in the base of each 
 cerebral hemisphere, subjacent to the island of Reil, they and it constitut- 
 ing the oldest part of the hemisphere, the first to appear in the order of 
 development. They are semi-detached local thickenings of the gray 
 cortex, and are named as follows: 
 
 Corpus Striatum, composed of two nuclei, the caudate and the len- 
 ticular (lentiform) (described on page 191). Closely associated with 
 it are certain fasciculi of white matter, the / 3cr/ 
 Internal Capsule (page 192). 
 External Capsule (page 192). 
 Anterior Commissure (page 192). 
 Tania Semicircularis (stria terminalis) (page 190). 
 Claustfum, a thin band of gray matter, described under the corpus 
 
 striatum on page 191. 
 
 Nucleus Amygdala, a thickening of the cortex of the apex of the 
 temporal lobe, producing a bulge, the amygdaloid tubercle, in the roof 
 of the extremity of the descending cornu of the lateral ventricle. 
 The Optic Thalamus, though in close proximity to the corpus striatum, 
 is not placed among the basal ganglia of the hemispheres, being considered 
 part of the diencephalon or inter-brain. 
 
 The White Matter consists of medullated fibres in bundles, arranged in 
 the following 3 systems: 
 
 PROJECTION FIBRES (peduncular), connecting the hemispheres with 
 the medulla oblongata and the cord. They originate in the cells of 
 the cerebral cortex from whence they proceed, forming the corona 
 radiata as they converge to enter the internal capsule when they are 
 
l8o HUMAN ANATOMY 
 
 collected into the several bundles which are continued as the crusta 
 (basis) of the crura (pedunculi) cerebri. 
 
 TRANSVERSE OR COMMISSURAL FIBRES, connect the two hemispheres. 
 They are the transverse fibres of the corpus callosum, and the anterior 
 and posterior commissures of the 3d ventricle. 
 
 ASSOCIATION FIBRES, connect different structures in the same hemi- 
 sphere; the short connecting adjacent convolutions; and the long, 
 connecting distant structures, as follows, the 
 
 Uncinate Fasciculus, from the frontal to the temporal lobe, 
 across the bottom of the fissure of Sylvius, (fissura cerebri 
 lateralis). 
 
 Cingulum, antero-posteriorly in the convolution of the corpus 
 
 callosum, from the anterior perforated substance to the hook 
 
 of the uncinate gyrus (anterior end of the sup. occipito-temporal 
 
 gyrus). 
 
 Superior Longitudinal Fasciculus, connects the frontal lobe with 
 
 the occipital and temporal lobes. 
 
 Inferior Longitudinal Fasciculus, connects the temporal with the 
 occipital'lobe. It runs the entire length of both lobes and con- 
 nects their convolutions. 
 Perpendicular Fasciculus, connects the inferior parietal lobule with 
 
 the inferior occipito-temporal convolution (gyrus fusiformis). 
 Fornix, connects the hippocampal convolution (superior occipito- 
 temporal) with the corpora albicantia (corpora mammillaria) 
 and the optic thalamus.. 
 
 THE MENINGES 
 
 Membranes of the Brain are the dura mater, the arachnoid membrane, 
 and the pia mater. 
 
 3 7 The Dura Mater is a dense fibrous membrane lining the interior of the 
 skull. It consists of two layers which are coalesced throughout the 
 greater part of their extent. The inner layer which is produced into the 
 intervals between parts of the brain forming partitions, and the outer 
 layer which is strongly attached at the base of the cranial cavity and 
 along the cranial sutures into which it sends processes. The outer 
 layer forms the internal periosteum of the cranial bones. It is con- 
 tinuous with the dura mater of the spinal cord, with the pericranium, 
 and the periosteum of the orbit; being prolonged to the outer surface of 
 the skull through the various foramina at its base. It sends 4 processes 
 into the cavity of the skull for the support of the different parts of the 
 brain, also several tubular processes and prolongations through orifices and 
 
THE MENINGES l8l 
 
 foramina in the skull for the protection of nerve trunks and vessels. The 
 Cerebral dura mater derives its nerve supply from the 4th and 5th cranial 
 nerves, and from the sympathetic (Whitaker). It presents the following 
 points for examination 
 
 Tht Mcningeal Arteries, are on, or close to, the outer surface, whereas 
 
 the veins are deeply placed between the two layers and form 
 
 sinuses (see page 164). 
 Falx Cerebri, an arched process into the longitudinal fissure of the brain 
 
 vertically; contains in its upper and lower margins the superior and 
 
 inferior longitudinal sinuses. 
 Tentorium Cerebelli, a lamina of dura mater supporting the posterior 
 
 lobes of the brain, and covering the upper surface of the cerebellum. 
 
 It incloses the lateral and superior petrosal sinuses. 
 Falx Cerebelli, projects between the lateral lobes of the cerebellum, 
 
 from the tentorium to the foramen magnum. 
 Diaphragma Sella, a horizontal process forming a small circular fold 
 
 which almost covers the pituitary body and constitutes a roof for the 
 
 sella turcica. 
 Pacchionian Bodies (granulationes arachnoideales), clusters of white 
 
 granulations situated on both the outer and inner surface of the dura 
 
 mater near the larger sinuses, and in the interior of the larger sinuses 
 
 (see page 182). 
 
 The Arachnoid Membrane is a delicate single-layer envelope which 
 covers the brain, lying between the dura mater and the pia mater, although 
 throughout a large part of its extent it is not distinct from the pia mater. 
 It is separated from the dura mater by the superficial cerebral veins. It 
 dips into the great longitudinal fissure of the brain and into the interval 
 between the cerebrum and cerebellum but it does not enter the fissures 
 between the convolutions of the brain. Processes of it are prolonged 
 around the cranial nerves as far as their points of exit from the skull. It 
 is supplied probably by the 5th, 7th and nth cranial nerves (Whitaker). 
 Subdural Space (cavum subdurale), is the space between the arach- 
 noid and the dura mater. It contains a small amount of fluid of the 
 nature of lymph. 
 
 Subarachnoid Space (cavum subarachnoidalis), is the interval between 
 the arachnoid and pia mater, forming the two large spaces, mentioned 
 below, at the base of the brain, but small on the surface of the hemi- 
 spheres. It is occupied by a spongy connective tissue, in the meshes 
 of which the cerebro-spinal fluid is contained. It communicates with 
 the genera] ventricular cavity of the brain by 3 openings, one of 
 
1 82 HUMAN ANATOMY 
 
 which, the foramen of Magendie (metapore), is in the middle line at 
 the lower end of the roof of the 4th ventricle. 
 
 Anterior Subarachnoidean Space (cisterna interpeduncularis), is the 
 interval between the arachnoid and the pia mater at the base of the 
 brain, where the former membrane extends across between the two 
 temporal lobes. 
 
 Posterior Subarachnoidean Space (cisterna cerebellomedullaris), is a 
 similar interval between the hemispheres of the cerebellum and the 
 medulla oblongata. These two spaces communicate with each other 
 across the inferior cerebellar peduncles (corpores restiformes). 
 
 Cerebro-spinal Fluid, occupies the subarachnoid space of the brain and 
 spinal cord, and also the ventricular cavities of the brain. Its 
 average quantity is about 2 oz., being most abundant in old persons. 
 It forms a water-bed for the protection of the nervous centres from 
 the effects of concussions. 
 
 Granulationes Arachnoideales or Pacchionian bodies, are numerous, 
 small, granulations, which are not glandular in structure but 
 enlarged normal villi of the arachnoid; found on the outer and 
 inner surfaces of the dura mater, in the superior longitudinal sinus, 
 and on the pia mater. They are not usually found until after the 
 7th year of age, and are occasionally wanting. 
 
 The Pia Mater is a vascular membrane, supplied by branches of the in- 
 ternal carotid and vertebral arteries. It covers the surface of the brain, 
 dipping down into all the sulci, and forms the velum interpositum (tela 
 chorioidea ventriculi tertii) and choroid plexus (plexus chorioideus 
 ventriculi lateralis) of the lateral and 4th ventricles. It consists of a 
 minute plexus of blood-vessels, held together by a very fine areolar tissue; 
 and contains numerous lymphatic vessels and nerves, the latter being 
 derived from both the cerebro-spinal and sympathetic systems. Its 
 nerve supply is derived from 3d, 5th, 6th, 7th and 8th cranial nerves and 
 from the sympathetic (Whitaker). 
 
 Weight of the Brain. Its average weight in the male adult is from 1360 
 (Smith) to 1400 (Spitzka) grammes; in the female 1250 grammes (Spitzka), 
 of which the cerebrum is about seven-eighths. 
 
 Divisions of the Brain. The Brain may be divided into the Cerebrum, 
 the Cerebellum, the Pons Varolii (pons) and the Medulla Oblongata; but 
 for the descriptive purposes it is best considered under the following 5 
 divisions, viz. the 
 
 Cerebral Hemispheres or Telencephalon, comprising the various lobes, 
 the lateral and 5th ventricles, and the basal ganglia. 
 
THE BRAIN 183 
 
 Inter-brain or Diencephalon, the region of the 3d ventricle, including 
 also the optic thalami and the pineal gland. 
 
 Mid-brain or Mesen-cephalon, comprising the crura cerebri, the corpora 
 quadrigemina, the corpora geniculata, and the aqueduct of Sylvius 
 (aquaeductus cerebri). 
 
 Hind-brain or Melencephalon, comprising the pons Varolii, the cere- 
 bellum, and the upper half of the 4th ventricle. 
 
 Medulla Oblongata or Myelencephalon, including the lower half of the 
 4th ventricle. 
 
 The Cerebrum or Telencephalon. The cerebrum presents an ex- 
 ternal surface of gray matter called the cortex, the large upper part 
 of which is called the Pallium or Mantle; the smaller lower or basilar 
 part is called the Rhinencephalon. The surface of the brain presents 
 numerous clefts; some of these clefts cause a corresponding projec- 
 tion into the cavities of the interior of the brain and are called 
 Fissures (fissurae) in order to distinguish them from the others called 
 Sulci, which are those clefts which separate lobes (or lobules) from each 
 other. Clefts that separate the lobes from each other are called 
 inter-lobular sulci, while those that divide lobes into convolutions or 
 gyri are known as intra-lobular sulci. The cerebrum is divided into 
 two hemispheres by the Great Longitudinal fissure (fissura longi- 
 tudinalis cerebri). 
 
 THE CEREBRAL HEMISPHERES 
 
 Lobes in each Hemisphere, are as follows: 
 Frontal Lobe, bounded internally by the longitudinal fissure, below by the 
 
 fissure of Sylvius (fissura cerebri lateralis), and posteriorly by the 
 
 fissure of Rolando (sulcus cerebri centralis). 
 Parietal Lobe, extending down to the fissure of Sylvius (fissura cerebri 
 
 lateralis), and antero-posteriorly from the fissure of Rolando (sulcus 
 
 cerebri centralis) to the external parieto-occipital fissure. 
 Occipital Lobe, behind the parieto-occipital fissure. 
 Temporal Lobe, lying in the middle fossa of the skull, and bounded in 
 
 front by the fissure of Sylvius (fissura cerebri lateralis). 
 Central Lobe, or Island of Reil (Insula), lies in the fissure of Sylvius 
 
 (fissura cerebri lateralis) covered by the frontal and temporal lobes. 
 Limbic Lobe, arches around the corpus callosum and the hippocampal 
 
 fissure; is well developed in animals having a keen sense of smell. 
 Olfactory Lobe, situated on the under surface of the frontal lobe, and 
 
 divided into the olfactory bulb, the olfactory tract, the trigonum, and 
 
184 HUMAN ANATOMY 
 
 the posterior olfactory lobule (ant. perforated space or substantia per- 
 forata anterior). 
 
 Fissures of the Cerebrum are as follows: 
 
 Longitudinal Fissure (fissura longitudinalis cerebri), extends from the 
 front of the cerebrum to the back, separating it into two hemispheres, 
 which are connected in the middle portion by the central commissure, 
 the corpus callosum (10), forming the floor of the fissure in this part of 
 its length. 
 
 Syhian Fissure, or Fissure of Sylvius (fissura cerebri lateralis), on each 
 side at the base and lateral side of the brain. Starting at the anterior 
 perforated substance it passes outward to the external surface of the 
 hemisphere, where it divides into a short anterior limb (ramus anterior 
 horizontalis), a short ascending limb (ramus anterior ascendens), and 
 a horizontal limb (ramus posterior). It lodges the middle cerebrav 
 artery. 
 
 Fissure of Rolando (sulcus cerebri centralis) (i), on the superior surface 
 of each hemisphere, extending from the longitudinal fissure about it? 
 centre, downward and forward toward the fissure of Sylvius, separating 
 the frontal and parietal lobes. This fissure is said to be found only in 
 man and the higher primates. 
 
 Parieto-occipital Fissure, extends from the longitudinal fissure outward 
 for about an inch between the parietal and occipital lobes. 
 
 Calloso-marginal Fissure (sulcus cinguli), above the gyrus fornicatus 
 (gyrus cinguli) on the inner surface of each hemisphere. 
 
 Internal Parieto-occipital Fissure, extends downward and forward to join 
 the calcarine fissure, on 'a level with the hinder end of the corpus cal- 
 losum. 
 
 Calcarine Fissttre (fissura calcarina), begins close to the posterior extrem- 
 ity of the hemisphere, runs horizontally forward, joined by the parieto- 
 occipital fissure, and terminates a little below the posterior end of the 
 corpus callosum (u). 
 
 Collateral Fissure, below and external to the preceding, runs forward 
 from the posterior extremity of the brain nearly as far as the tip of the 
 temporal lobe. 
 
 Dentate or Hippccampal Fissure, commences behind the posterior end 
 of the corpus callosum (n) and runs forward to the recurved part 
 (uncinate gyrus) of the hippocampal gyrus (posterior horizontal part 
 of the sup. occipi to- temporal convolution). 
 
 Transverse Fissure, a horse-shoe shaped gap or cleft at the base of the 
 brain, extending from the foramen of Munro on each side to the termina- 
 
THE BRAIN 
 
 FIG. 71. 
 
 tion of the descending cornu of the lateral ventricle. One-half the 
 fissure is in each hemisphere, and it admits an invagination of the pia 
 mater, which forms the choroid plexus in the lateral ventricle and the 
 velum interpositum (tela chorioidea ventriculi tertii) in the 3d ventricle. 
 It gives exit to the venae Galeni. 
 
 Parallel Fissure, formerly called the first temporo-sphenoidalfisstire, on the 
 lateral surface of the hemisphere below the fissure of Sylvius (fissura 
 cerebri lateralis). 
 
 Cerebral Convolutions. The superior and inner surfaces of each hemi- 
 sphere are formed of convolutions (gyri) with intervening fissures and de- 
 pressions (sulci) of various depths, 
 the gyri and sulci being both 
 formed of gray matter thus ar- 
 ranged to enable it to present a 
 great extent of surface. The con- 
 volutions are not uniform in all 
 brains as to arrangement, nor are 
 they symmetrical in the two 
 hemispheres. The principal con- 
 volutions are the following- 
 named : 
 
 On the Frontal Lobe are 8, ex- 
 t e r n a 1 1 y the ascending 
 (gyrus centralis anterior) 
 (2), superior (4), middle (5) 
 and inferior (6) frontal; in- 
 feriorly the internal, anterior 
 and posterior orbital. The 
 inferior frontal on the left 
 side is named the convolution 
 of Broca and is the language 
 centre. 
 
 On the Parietal Lobe., are 4, 
 externally the ascending 
 (gyrus centralis posterior) 
 (3), superior and inferior 
 parietal, and the quadrate or 
 
 precuneus, internally. The inferior parietal is subdivided into the 
 supramarginal, the angular, and postparietal gyri, the latter (2) lying 
 around the posterior end of the superior temporal sulcus (parallel 
 fissure) (see above). 
 
1 86 HUMAN ANATOMY 
 
 The Occipital Lobe has 4, externally the superior (7), middle (8) and 
 inferior (9) occipital; and internally the cuneate lobule or cuneus. 
 
 Temporal Lobe has 5 gyri, externally, the superior, mfddle, and 
 inferior temporal gyri; below on the tentorial surface, the superior 
 occipito-temporal (gyrus lingualis or subcalcarine), and the inferior 
 occipi to- temporal (gyrus fusiformis). Part of the inferior temporal 
 gyrus also shows on this surface. On the upper surface, two or three 
 indefinite gyri can be seen. The superior occipito-temporal lobe is by 
 some considered to be two lobes, in which case, its anterior, upwardly 
 hooked portion is called the uncinate gyrus, the posterior horizontal 
 portion being called the hippocampal gyrus. 
 
 The Central Lobe or Island of Reil (insula), is subdivided by the sulcus 
 centralis into the precentral lobe (pars frontalis) and the postcentral 
 lobe (pars occipitalis). The insula is pyramidal in shape and consists 
 of 5 or 6 convolutions called gyri operti. 
 
 Under Surface of the Base of the Brain, from before backward, ex- 
 cluding the vessels and the cranial nerves, shows the following points for 
 examination. In the middle line are the 
 
 Longitudinal Fissure, its anterior portion separating the frontal lobes, 
 and its posterior portion between the occipital lobes. 
 
 Corpus Callosum, the great transverse commissure, seen in the longi- 
 tudinal fissure, and showing its peduncles, one on each side, to meet 
 the corresponding outer root of the olfactory tract. 
 
 Lamina Cinerea, a thin, triangular, gray layer, continuous with the 
 anterior perforated space (locus perforatus anterior). In the mid- 
 line it is divided into a right and a left portion by a very thin almost 
 transparent portion the lamina terminalis, which forms the anterior 
 and inferior boundary of the 3d ventricle. 
 
 Optic Commissure, formed by the junction of the optic tracts. 
 
 Tuber Cinereum (17) a gray lamina behind the optic commissure, form- 
 ing part of the floor of the third ventricle. From it projects the 
 
 Infundibulum, a hollow process, its canal connecting the pituitary 
 cavity with the 3d ventricle in the foetus. 
 
 Eminentia Saccularis, between the corpora albacantia or mammillaria 
 and the tuber cinereum, it is a trefoil-shaped eminence homologous 
 with the saccus vasculosus of the lower vertebrates. 
 
 The Pituitary Body or Gland (Hypophysis Cerebri), is a small oval body 
 depending by the infundibulum from the tuber cinereum in the floor 
 of the third ventricle. It occupies the pituitary fossa (fossa hypo- 
 physeos) in the sella turcica of the sphenoid bone. It consists of two 
 
THE BRAIN 
 
 FIG. 72. 
 
 27 
 
 THE BASE OF THE BRAIN 
 
 i. Olfactory Bulb. 2. Second, or Optic Nerves. 3. Anterior Perforated Space. 
 4. Optic Tract. 5- Crus Cerebri. 6. 3d Nerve. 7. 4th Nerve. 8. sth Nerve. 9. 
 6th Nerve. 10. Pyramid, n. Olivary Body. 12. Vertebral Artery. 13. Anterior 
 Spinal Artery. 14. Anterior Cerebral Artery. 15. Lamina Cinerea. 16. Middle 
 Cerebral Artery. 17. Tuber Cinereum. 18. Corpora Albicantia. 19. Posterior 
 Perforated Space. 20. Posterior Cerebral Artery. 21. Superior Cerebral Artery. 
 22. Pons Varolii. 23. Inferior Cerebellar Artery. 24. 7th and Sth Nerves. 25. 
 9th, loth and nth Nerves. 26. I2th Nerve. 27. Cerebellum. 
 
1 88 HUMAN ANATOMY 
 
 lobes. Anterior (buccal or glandular) lobe is the larger, it secretes 
 a colloid substance much like that of the thyroid gland (glandula 
 thyreoidea). Its structure is much like that of the para-thyreoid 
 bodies. It consists of compartments which are lined with cuboidal 
 cells of two varieties. The principal cells are the more numerous; 
 they are small cells with very granular cytoplasm. The large cells 
 are chromophile cells. The anterior lobe is derived from the primitive 
 buccal cavity (stomatodaeum). Posterior or cerebral lobe is the 
 smaller and is connected by the infundibulum to the tuber cinereum, 
 but is not known to be functional. It is composed chiefly of neu- 
 rogliar connective tissue and blood-vessels, throughout which are 
 interspersed numerous branched cells. It has no organized structure. 
 It is derived from the hypophyseal diverticulum of the diencephalon. 
 The hypophysis gets its blood supply from the hypophyseal branches 
 of the internal carotid artery, it is classed as one of the ductless glands. 
 
 Corpora Albicantia (corpora mammillaria) (18), two round, white 
 eminences, united together; they are the anterior crura of the fornix 
 folded on themselves. 
 
 Posterior Perforated Space (Pans Tarini or Substantia Perforata Posterior} 
 (19), perforated for vessels to the optic thalami; forms part of the 
 floor of the 3d ventricle. 
 
 Pons Varolii (pons) (22), a broad band of white fibres, passing from 
 one cerebellar hemisphere to the other described on page 203. 
 
 Medulla Oblongata (13), pyramidal in form, emerges from the posterior 
 
 border of the pons Varolii. It is described on page 208, 
 On each side of the middle line are seen the 
 
 Frontal Lobe, its under surface (see ante, page 185); lying thereon is 
 the 
 
 Olfactory Lobe, consisting of the olfactory bulb (i), the olfactory 
 tract, the trigonum olf actorium, and the posterior olfactory lobule or 
 anterior perforated space (3). 
 
 Anterior Perforated Space (substantia perforata anterior), (3) or pos- 
 terior olfactory lobule, at the commencement of the fissure of Sylvius 
 (fissura cerebri lateralis); is perforated for small arteries going 
 to the corpus striatum. 
 
 Fissure of Sylvius (fissura cerebri lateralis), is described on page 184. 
 
 Optic Tract (4), runs obliquely across the crus cerebri as a flat band, 
 and enters into the optic commissure. 
 
 Crus Cerebri or Cerebral Peduncle (5), a thick bundle of white matter 
 in front of the anterior border of the pons, passing forward and out- 
 ward to enter the undfir surface of the hemisphere. The two crura 
 
THE BRAIN 189 
 
 connect the cerebrum with the cerebellum, medulla oblongata and 
 
 spinal cord. With the optic tracts they form the boundaries of the 
 
 inter -peduncular space. 
 
 Temporal Lobe, its under surface (see page 186). 
 Cerebellum (27), covering the occipital lobe of the cerebrum. It is 
 
 described separately on page 206. 
 
 Ventricles of the Brain are 5 in number, of which the two lateral and 
 the 5th belong to the cerebral hemispheres, the 3d is the cavity of the 
 interbrain, and the 4th belongs to the cerebellum and the medulla oblon- 
 gata. They are situated as follows: 
 
 Two Lateral Ventricles, (ventriculi laterales), within the substance of 
 
 the hemisphere, one in each; they are connected with the 3d 
 
 ventricle and indirectly with each other by the foramina of Munro 
 
 (foramina interventricularia) and the 3d ventricle. 
 
 Third Ventricle (ventriculus tertius), a narrow crevice between the 
 
 optic thalami, lying below the lateral ventricles and communicating 
 
 with them by the foramina of Munro (foramina interventricularia). 
 
 It is connected with the 4th ventricle by the iter a tertio ad quartum 
 
 ventriculum or aqueduct of Sylvius (aquaeductus cerebri). 
 
 Fourth Ventricle (ventriculus quartus), between the cerebellum and 
 
 the medulla oblongata. 
 
 Fifth Ventricle (cavum septi pellucidi), between the two laminae 
 of the septum lucidum (septum pellucidum), between the two lateral 
 ventricles. It is not a true ventricle. 
 
 The Lateral Ventricles are two irregular cavities in the cerebral hemi- 
 spheres, separated from each other by a partition, the septum lucidum, 
 (or pellucidum), and each having a central cavity and 3 prolongations or 
 cornua, the anterior in the frontal lobe, the middle in the temporal lobe 
 and the posterior in the occipital lobe. They communicate with each 
 other and with the 3d ventricle by the foramina of Munro (foramina 
 interventricularia). The central cavity (pars centralis) is situated in the 
 parietal lobe and is bounded as follows: 
 
 Roof, the under surface of the corpus callosum. 
 
 Floor, from before backward, the caudate nucleus of the corpus 
 
 striatum, taenia semicircularis (stria terminalis), optic thalamus, 
 
 choroid plexus, the thin sharp free edge of the lateral half of the 
 
 fornix and its posterior pillar. 
 
 Internally, the septum lucidum (septum pellucidum), separating it 
 
 from the opposite ventricle. 
 Externally, in front and behind, brain-substance. 
 
190 HUMAN ANATOMY 
 
 Structures named above are briefly described as follows: 
 
 Corpus Callosum, the great transverse commissure, arching backward 
 to become continuous with the fornix, reflected below, forming the 
 peduncles at the entrance of the fissure (lateral cerebral) of Sylvius; 
 and marked above by a depression, the Raphe, and longitudinal ele- 
 vations, the stria longitudinales, mediates and laterales, or nerves of 
 Lancisi. 
 
 Septum Lucidum (septum pellucidum), consists of 2 layers of white 
 and gray matter, lined by epithelium; is placed vertically between the 
 lateral ventricles, from the raphe of the corpus callosum above to 
 the fornix below. The cavity in its centre is the 5th ventricle (or 
 cavum septi pellucidi). 
 
 Fornix, is a commissure situated beneath the corpus callosum, but 
 continuous with it posteriorly, the septum lucidum (s. pellucidum) 
 separating them in front. It is composed of association fibres 
 which are axis-cylinder processes connecting different parts of the 
 same hemisphere. It is of triangular form with the apex in front. 
 Its anterior pillars curve downward to the base of the brain, are there 
 reflected, forming the corpora atticantia (corpora mammillaria), 
 and end in the optic thalami. Its posterior pillars (crura fornicis) 
 pass down the descending horns of the lateral ventricles, along the 
 concavities of the hippocampi majores, and are each continued as the 
 corpus fimbrialum or t&nia hippocampi, into the uncus or hook of 
 the hippocampal convolution. The Lyra (psalterium) is a series of 
 markings on its under surface. 
 
 Foramina of Munro (foramina inter ventricularia), together form a 
 Y-shaped opening situated between the anterior pillars of the fornix 
 in front and above and the anterior extremities of the optic thalami 
 below and behind. Each is crescentic in outline and by it the lateral 
 ventricles communicate with the 3d ventricle and with each other. 
 
 Tania Semicircular is (Stria Terminalis), consists of commissural 
 fibres passing between the corpus striatum and the optic thalamu?. 
 
 Choroid Plexus of Veins, is the margin of a fold of pia mater which 
 enters at the transverse fissure, passes up the descending cornu, 
 through the foramen of Munro, and as the Velum Interpositum 
 (tela chorioidea ventriculi tertii) spreads out over the roof of the 3d 
 ventricle. 
 
 Corpus Striatum, is described on page 191. 
 
 Optic Thalamus, is described on page 193. 
 
 Cornua of the Lateral Ventricles. The Anterior Cornu (cornu anterius) 
 curves over the anterior end of the corpus striatum into the frontal lobe. 
 
THE BRAIN 191 
 
 The Posterior Cornu (cornu posterius) curves downward and inward in 
 the occipital lobe, and contains a smooth eminence, the Hippocampus 
 Minor, which is caused by the calcarine fissure; below thisis a slight eleva- 
 tion called the calcar avis. As the calcar avis and the hippocampus 
 diverge from each other they leave a triangular interval called the tri- 
 gonum collaterals. The Middle Cornu (cornu inferius) descends into 
 the temporal lobe to the transverse fissure at the base of the brain, 
 curving backward, outward, downward, forward, and inward (initials 
 of the directions form the mnemonic word BODFI). On its floor are the 
 following: 
 
 Hippocampus Major, a white eminence, about 2 inches long, formed 
 by the infolding of the cerebral cortex to produce the dentate or hippo- 
 campal fissure. 
 
 Pes Hippocampi, the scolloped end of the hippocampus. 
 Pes Accessorius (Eminentia Collateralis] , between the hippocampi, at 
 the junction of the middle and posterior cornua, it is caused by the 
 collateral fissure. 
 Corpus Fimbriatum, a continuation of the posterior pillar of the fornix 
 
 (crus fornicis). 
 
 Choroid Plexus of Veins, a process of pia mater (see page 190). 
 Dentate Convolution (fascia dentata), a band of gray matter, just 
 below the fimbria, its free border is notched by the branches of the 
 choroid artery. 
 
 Transverse Fissure (fissura chorioidea), at the extremity of the cornu, 
 extending to the foramena of Munro (foramena interventricularia). 
 It is described on page 184. 
 
 The Fifth Ventricle (cavum septi pellucidi) is a narrow chink situated 
 between the layers of the septum lucidum (septum pellucidum), and there- 
 fore lies between the lateral ventricles. In the ftetus it communicates 
 with the 3d ventricle by an opening between the anterior pillars of the 
 fornix (columnar fornicis). Originally it was part of the longitudinal 
 fissure and was shut off by the union of the hemispheres in the formation 
 of the corpus callosum above and the fornix below. It usually contains 
 fluid, of the nature of lymph. 
 
 The Corpus Striatum is a body of gray matter imbedded in the white 
 substance of each hemisphere, and is partly seen in the lateral ventricle 
 and its anterior cornu, this part being the 
 
 Nucleus Caudatus (caudate nucleus), the intra-ventricular portion; a 
 pear-shaped mass having its narrow end on the outer side of the optic 
 thalamus. 
 
IQ2 HUMAN ANATOMY 
 
 Nucleus Lentiformis (lenticular nucleus), the extra- ventricular por- 
 tion, only seen in sections of the hemisphere. It is divided by the 
 white external and internal laminae into three portions, the two medial 
 portions together constitute the globus pallidus, the remaining part 
 is much the larger and is called the putamen. 
 
 Internal Capsule, a curved lamina of white matter separating the 
 caudate nucleus from the lenticular (lentiform) posteriorly. It is 
 formed by projection fibres from the crus cerebri, the corpus stria- 
 turn and the optic thalamus. [Projection fibres are axis-cylinder 
 processes connecting cells in the gray matter of the hemispheres 
 with other cells at lower levels in the cerebro-spinal axis.] Its 
 anterior limb (pars frontalis) is the portion in front of the curve 
 or genu, its posterior limb (pars occipitalis) lying behind the genu. 
 
 External Capsule, a lamina of white matter bounding the putamen of 
 the lenticular (lentiform) nucleus externally, and made up of asso- 
 ciation fibres from the anterior commissure and the subthalamic 
 region. 
 
 Claustrum, a thin layer of gray matter on the outer surface of the 
 external capsule, regarded as a detached portion of the gray matter 
 of the island of Reil (insula). 
 
 THE INTER-BRAIN 
 
 The Inter -brain or Thalamen-cephalon (Diencephalon) is the region 
 of the 3d ventricle, and is connected in front and above with the cerebral 
 hemispheres, behind with the mid-brain or mesencephalon. Its upper 
 surface is covered by iheforrrix; inferiorly it reaches the base of the brain, 
 it comprises the following structures, optic thalami, corpora geniculata 
 (metathalamus), pineal body (corpus pineale), posterior part of the 
 tuber cinereum, posterior part of the third ventricle, corpora albicantia 
 (corpora mammillaria), optic nerve, and optic tract. 
 
 The Third Ventricle (ventriculus tertius) is a mere fissure, situated 
 in the mid-line, between the optic thalami. It communicates with the 
 lateral ventricles above by the foramina of Munro (foramina interven- 
 tricularia) and with the 4th ventricle behind by the iter a terio ad 
 quartum ventriculum (aquaeductus cerebri). It is crossed by 3 bands, 
 the anterior, middle, and posterior commissures, the middle one being of 
 gray matter, the others of white. 
 
 Anterior Commissure, is composed of commissural fibres, it appears to 
 connect together the corpora striata; its fibres are traced into the 
 temporal lobes, and include fibres from the olfactory tract of the 
 
THE BRAIN 193 
 
 opposite side. Commissural fibres are axis-cylinder processes which 
 
 connect identical parts of the two hemispheres. 
 Middle Commissure (massa intermedia), is composed of gray matter 
 
 and connects the two optic thalami. 
 Posterior Commissure, is composed of commissural fibres (see above); it 
 
 stretches across from one optic thalamus to the other, and contains 
 
 fibres connecting the two thalami, besides decussating fibres from 
 
 various parts of the mid-brain. 
 Boundaries of the Third Ventricle are as follows: 
 Roof, the velum interpositum (tela chorioidea ventriculi tertii), and 
 
 above it the fornix. 
 Floor, the parts comprised in the interpeduncular space at the base of 
 
 the brain, viz. the tuber cinereum, with its infundibulum and 
 
 pituitary body, corpora albicantia (corpora mammilaria), posterior 
 
 perforated space (substantia perforata posterior). Eminentia sac- 
 
 cularis, and chiasma optica. 
 Anteriorly, the anterior pillars of the fornix (columnae fornicis), and 
 
 the lamina terminalis which joins the right and left half of the lamina 
 
 ceneria. 
 Posteriorly, the pineal gland (corpus pineale), posterior commissure 
 
 and the iter a terio ad quartum ventriculum (cerebral aqueduct). 
 Laterally, the optic thalami and the peduncles of the pineal body. 
 
 The Optic Thalami are two large, oblong masses, composed mainly of 
 gray matter and situated on either side of the 3d ventricle, between the 
 diverging portions of the corpora striata. Their outer and inferior 
 surfaces are blended with contiguous parts of the brain; their upper, inner 
 and posterior surfaces are free. They are intimately connected, by com- 
 municating fibres, with the tegmenta of the crura cerebri, the optic tract, 
 the cerebral cortex, the corpora striata and the corpora albicantia (corpora 
 mammillaria). Each optic thalamus terminates anteriorly as a rounded 
 point 
 
 Anterior Tubercle, containing the anterior nucleus. 
 
 As they pass backwards the optic thalami diverge outwards from 
 each other and each terminates as a rounded swelling, the 
 
 Posterior Tubercle or Pulvinar to which is attached laterally the external 
 geniculate body (corpus geniculatum laterale). 
 
 Corpora Geniculata (metathalamus) four oval eminences, a pair of 
 which is situated below and external to the pulvinar of the thalamus 
 on each side of the brain. 
 
 External Geniculate Body (corpus geniculatum laterale) the larger of the 
 
IQ4 HUMAN ANATOMY 
 
 pair, is at a higher level and is slightly anterior as well as external 
 or lateral to the internal geniculate body (corpus geniculatum 
 mediale). The external geniculate body (corpus geniculatum 
 laterale) belongs to and is properly a part of the optic thalamus, it 
 receives the outer or lateral limb of the optic tract. 
 Internal Geniculate Body (corpus geniculatum mediale) receives the 
 outer part of the inner or medial limb of the optic tract. These 
 fibres do not however enter the eye, they originate in one of the 
 inferior corpora quadrigemina (colliculus inferior) on one side of the 
 brain, run forwards, cross by way of the optic chiasm, and then run 
 backwards to the internal (lateral) genicutate body and inferior 
 colliculus of the side opposite to that of their origin, this constitutes 
 what is known as the commissure of Gudden. 
 
 Pineal Body (corpus pineale), or epiphysis cerebri, is a small oval, 
 reddish vascular body (or gland), situated in front of the anterior 
 corpora quadrigemina (colliculi superiores) in the mid-line, just 
 over the opening of the aquaeductus cerebri (Sylvius) into the third 
 ventricle. It derives its blood supply from the velum interpositum 
 (tela chorioidea ventriculi tertii) to which it is firmly attached. It 
 has two peduncles which run forwards, one on each side of the third 
 ventricle, on the inner or medial surfaces of the optic thalami, to join 
 the anterior pillars of the fornix (columnae fornicis). 
 The pineal body, classed as one of the ductless glands, is not com- 
 posed of nervous elements but consists of numerous follicles which are 
 lined by epithelium. Some of the follicles are filled with a very viscid 
 liquid containing many epithelial cells constituting what are known as 
 corpora amylacea, some contain sabulous concretions of lime, magnesia, 
 and ammonia salts (brain sand) constituting what is known as the acervulus 
 cerebri. The pineal body is homologous to the so-called "pineal eye" of 
 some reptiles and some of the other lower vertebrates. 
 
 Trigonum Habenulae, a small triangular space with the apex pointing 
 forward, and its base corresponding to one of the anterior corpora 
 quadrigemina (colliculus superior). It is the interval between one 
 of the crura or peduncles of the pineal body and the optic thalamus of 
 the same side. In this triangle is a cluster of nerve cells forming the 
 ganglion habenulce. 
 
 The Mesencephalon or Mid-brain is the so-called isthmus cerebri. 
 It is the constricted portion which connects the pons (varolii) with the 
 diencephalon (inter-brain or thalamen-cephalon) and the cerebral hemi- 
 spheres. Comprised in it, on its ventral surface are the two crura (pedun- 
 
THE BRAIN I 95 
 
 culi) cetebriy and on its dorsal surface are the four corpora quadrigemina 
 (colliculi). It is traversed by the eqtusductus cerebri (Sylvius). Above 
 and in front, it is continuous with the diencephalon or inter-brain, and 
 below with the pons Varolii. 
 
 The Crura Cerebri (pedunculi cerebri), two thick conical stalks 
 which constitute the stems of the cerebral hemispheres, are the upward 
 continuation of the medulla oblongata. Their parallel portions are 
 blended and held together by a mesial raphe which is indicated in front 
 or ventrally by a longitudinal groove. This portion is covered in front 
 or ventrally by the pons Varolii. The crura (peduncles) as they emerge 
 above the upper border of the pons Varolii, diverge laterally from 
 each other, enlarging as they ascend. 
 
 Each crus (pedunculus) then passes beneath the optic thalamus and 
 enters a cerebral hemisphere and continues to the internal capsule. As 
 seen from in front or ventrally, the interval between the divergent crura 
 (pedunculi) cerebri is called the inter-peduncular space. 
 
 In this space are the corpora albicantia (corpora mammillaria) . 
 The floor of the space is formed by the substantia perforata posterior also 
 called the posterior perforated space. The inner or medial sides of the 
 crura (pedunculi) cerebri are grooved by the superficial origin of third or 
 oculo-motor nerves. Winding forward around the outer or lateral 
 sides of the crura (pedunculi) cerebri are the optic tracts and below them, 
 the fourth or trochlear nerves. On the dorsal surface of the crura 
 (pedunculi) cerebri are the corpora quadrigemina (colliculi) supported 
 by the lamina quadrigemina covering in the aquaeductus cerebri 
 (Sylvius). 
 
 Upon cross section, each crus (peduncle) will be found to consist of 
 two portions which are separated from each other by a darker colored 
 portion called the substantia nigra, the portion that is in front of or 
 ventral to the substantia nigra is the Crusta or Pes (Basis Pedunculi) 
 Cerebri; the portion that is behind or dorsal to the substantia nigra is the 
 Tegmentum. 
 
 The Crusta (Basis Pedunculi) Cerebri constitutes the anterior or ventral 
 part of the crura (pedunculi) cerebri. It is composed entirely of longi- 
 tudinal fibres which descend from the cerebral hemisphere (corticifugal 
 fibres) most of which are continuous with the pyramidal tracts of the 
 medulla. Three principal tracts or bundles are recognized: ist, pyramidal 
 tracts in the middle and inner portions of the crusta, the inner part being 
 the geniculate fasciculus and the outer the pyramidal tracts proper; 2d f 
 cortico-pontine; and 3d, caudate-cerebellar tracts. 
 
196 HUMAN ANATOMY 
 
 The pyramidal (cerebro-spinal) tracts are direct motor strands com- 
 posed of descending cortico-spinal projection fibres which originate in the 
 following way. As the axis-cylinder processes descend from cells in the 
 precentral cerebral cortex, they form the corona radiata by converging as 
 they approach the internal capsule. They then proceed through the 
 genu and the anterior two-thirds of the posterior limb (pars ocdpitalis} of 
 the internal capsule to be continued as the pyramidal tracts in the crusta 
 (basis) of the crus (pedunculus) cerebri. Here they are differentiated 
 into an inner and an outer portion. 
 
 The inner portion is the part of the pyramidal tract that came down 
 through the genu of the internal capsule, it is continued as the gen- 
 iculate fasciculus, the fibres of which terminate in the nuclei of the 
 5th, yth, and i2th cranial nerves. 
 
 The outer portion of the pyramidal tract is the part that traversed the 
 anterior two-thirds of the pars ocdpitalis (posterior limb) of the in- 
 ternal capsule, it is continued as the, 
 
 i. Pyramidal Tract Proper through the pons Varolii into the anterior 
 pyramid (ventral area) of the medulla where its fibres are differenti- 
 ated into three strands, the crossed, the direct, and the uncrossed. 
 Crossed Pyramidal Tract (fasciculus cerebro-spinalis lateralis). 
 Most of the fibres of the pyramidal tract proper decussate in the 
 medulla (inferior pyramidal motor decussation) and are then con- 
 tinued downwards as the crossed pyramidal tract (lateral cerebro- 
 spinal fasciculus) in the lateral column (funiculus lateralis) of the 
 spinal cord (medulla spinalis), on the side opposite to that of their 
 origin, to ultimately become connected with the anterior roots of 
 the spinal nerves. 
 
 Direct Pyramidal Tract (fasciculus cerebro-spinalis anterior) or 
 fasciculus of Tiirck, is composed of fibres of the pyramidal tract 
 proper which do not decussate in the medulla but continue downwards 
 in anterior column (funiculus anterior) of the spinal cord (medulla 
 spinalis), on the same side as that of their origin, where at various 
 levels its fibres cross through the gray matter of the cord to become 
 connected with anterior nerve roots of the opposite side. 
 Uncrossed Pyramidal Tract comprises those fibres of the pyramidal 
 tract proper which do not decussate either in the medulla or in the 
 cord but continue downwards in the lateral column (funiculus lateralis) 
 of the spinal cord (medulla spinalis), on the same side as that of their 
 origin, where they mingle with the fibres of the crossed pyramidal 
 tract (fasciculus cerebro-spinalis lateralis) and become connected 
 with anterior nerve roots on the same side as that of their origin. 
 
THE BRAIN IQ7 
 
 2. The Cortico-pontine Tracts are the first link of the neurone chain 
 constituting the indirect motor tract, the complete series being 
 cerebral cortex; cortico-pontine tract; nucleus points; cerebellar 
 cortex; dentate nucleus; superior peduncle (brachium conjunctevum) 
 of cerebellum; red nucleus (nucleus ruber); rubro-spinal tract; 
 spinal gray matter; spinal nerve to muscle. There are two groups 
 of cortico-pontine fibres, 
 
 Fr onto- p online tract, during its passage through the cerebral peduncle 
 lies medial to the geniculate fasciculus of the pyramidal tract. Origi- 
 nating in the mid-frontal cortex, its fibres pass through the back 
 part of the anterior limb (pars frontalis) of the internal capsule con- 
 tinuing by way of the crusta (basis) pedunculi cerebri to the nucleus 
 pontis. 
 
 Temporo-pontine tract which lies posterior and lateral to the principal 
 portion of the pyramidal tract during its course through the crus 
 (pedunculus) cerebri. Originating in the cortex of the two lowermost 
 temporal gyri, its fibres pass inwards under the lenticular (lentiform) 
 nucleus, traverse the postero-inferior part of the posterior limb 
 (pars occipitalis) of the internal capsule, continuing by way of 
 the crusta (basis) of the crus (pedunculus) cerebri to the nucleus 
 pontis. 
 
 3. Caudate-cerebellar Tract (stratum intermedium) occupies the interval 
 ""between the substantia nigra which is posterior, and the pyramidal 
 
 and cortico-pontine tracts which surround it in front and laterally. 
 It is made up of fibres running from the caudate nucleus to the 
 cerebellum. 
 
 Substantia Nigra, is a dark band of pigmented gray matter, semi- 
 lunar in cross section. It divides the basilar (crusta) portion of the 
 cerebral peduncle (crus) from the tegmental portion. 
 
 Tegmentum, of the cerebral peduncle (crus) consists of network of 
 transverse and longitudinal fibres among which are enmeshed many 
 scattered nerve cells and two well-defined clusters of nerve cells. 
 The gray matter (substantia grisea) of the tegmentum is continu- 
 ous with the formatio reticularis of the pons and medulla, the prin- 
 cipal nuclear clusters are, 
 
 1. Stratum Griseum Cenlrale, which is the gray matter surrounding 
 the aquasductus cerebri (Sylvius). 
 
 2. Red Nucleus (nucleus tegmenti ruber), consists of multi-polar 
 cells, it is situated beneath the anterior corpus quadrigeminum 
 (colliculus superior). 
 
 It is the termination of the superior cerebellar peduncles (brachia 
 
198 HUMAN ANATOMY 
 
 conjunctiva). Some of the fibres originating in it run up to the 
 ventro-lateral nucleus of the thalamus, others descend in the rubro- 
 spinal tract. 
 
 While Matter (substantia alba), of the tegmentum consists both of 
 transverse and longitudinal fibres. Its transverse fibres mostly 
 enter into the formation of oculo-motor and trochlear nerves, q. v. 
 Its longitudinal fibres are mostly sensory and ascend towards the 
 brain cortex (corticipital). They are differentiated into the follow- 
 ing main bundles. 
 
 i. Medial Lemniscus (medial fillet). The tegmental and pontine 
 portion consists of ascending (corticipital) sensory nerve fibres after 
 they have emerged from the superior pyramidal sensor.y decussation 
 which is just above the nucleus gracilis and nucleus cuneatus in the 
 back part of the medulla oblongata. They convey sensory impulses 
 from muscles, bones, and joints. The medial lemniscus is formed by 
 the combination of fibres arising from the nuclei of the fasciculus 
 gracilis and fasciculus cuneatus. They originate in the following 
 way, The sense-organs in muscles, bones, and joints are connected 
 by the peripheral processes (dendrites) to the ganglion cells (ist 
 neurones of the chain) in the ganglia on the posterior roots of the spinal 
 nerves, by way of which, the central processes (axones) of those cells 
 enter and then run upwards in the posterior column (funiculus 
 posterior) of the spinal cord (medulla spinalis) on the same side as 
 that of their origin. All those coming from spinal nerves below the 
 8th thoracic, are combined to form the Fasciculus Gracilis (column 
 of Goll) occupying the medial portion of the posterior column (funicu- 
 lus posterior) of the cord, in which position it continues as it runs 
 upwards to the medulla where it terminates in an expansion enclosing 
 the nucleus gracilis, this upper portion being known as the clava. 
 The Fasciculus Cuneatus (column of Burdach) originates in exactly 
 the same way from all of the spinal nerves above the Qth thoracic. 
 It runs upwards, laterally to the fasciculus gracilis, in the posterior 
 column (funiculus posterior) of the cord until it reaches the medulla 
 in which it terminates as an expansion enclosing the nucleus cuneatus. 
 The 2d neurones of the chain after leaving the nucleus gracilis or 
 nucleus cuneatus, may go by way of the inferior cerebellar peduncle 
 (corpus restifcrme) to the cerebellar cortex of the opposite side, or 
 they may decussate in the medulla (superior Pyramidal sensory 
 decussation) and then proceed as medial lemniscus or fillet by way of 
 the pons through the tegmentum of the crus (pediculus) cerebri of 
 the side opposite to that of their origin; then through the thalamus, 
 
THE BRAIN 1 99 
 
 or through the posterior limb (pars occipitalis) of the internal capsule, 
 to the cerebral cortex. 
 
 2. Lateral Lemniscus (lateral fillet), is the upward continuation of 
 the cochlear division of the central auditory tract. Its fibres are 
 derived in the following way, The cochlear nerve arises from the cen- 
 tral processes of the T-shaped cells (ist neurone of the chain) in the 
 spiral ganglion of the cochlea, it then passes backwards and 
 enters the medulla, beneath the lower border of the pons on 
 the outer side of the restiform body. Its fibres then divide into 
 ascending and descending branches. The fibres of the ascending 
 branch terminate in the cells of the ventral cochlear nucleus, which 
 lies in front of the restiform body in the interval between the cochlear 
 and vestibular divisions of the auditory nerve (n. acusticus). The 
 fibres of the descending branch terminate in the cells of the dorsal 
 cochlear nucleus, which lies beneath the trigonum acusticum, behind 
 the restiform body and between it and the flocculus of the cerebellum. 
 The axones of the cells (2d neurone) in the dorsal and ventral 
 cochlear nuclei form two bundles, of which the dorsal bundle or striae 
 medullares cross the floor of the 4th ventricle to the medial plane in 
 which they penetrate the tegmentum and decussate, some of the 
 fibres entering the lateral lemniscus of the opposite side, others enter- 
 ing the trapezoid body (corpus trapezoideum). 
 
 The axones in the ventral bundle (trapezia!) enter the trapezoid body 
 where some of them terminate in the large cells (3d neurone) constituting 
 the nucleus trapezoideus. Most of these trapezial axones decussate before 
 terminating in the superior olive. The axones leaving the superior olive 
 (4th neurone) are joined by the axones of the dorsal bundle (strife medul- 
 lares) so constituting the lateral lemniscus (lateral fillet) which bends 
 upwards and is again interrupted by the nucleus lemnisci lateralis (5th 
 neurone) whence it proceeds by way of the tegmentum to the nucleus of 
 the posterior quadrigeminal body (colliculus inferior) (6th neurone) and 
 to the medial geniculate body (;th neurone) from which arise axones that 
 pass through the sub-lenticular portion of the internal capsule, then by way 
 of the temporal portion of the corona radiata to the auditory area in the 
 cortex of the superior and transverse temporal gyri. A few fibres reach the 
 posterior corpora quadrigemina (colliculi inferiores) without having 
 decussated. 
 
 3. Ventral Longitudinal Fasciculus (tecto-spinal or mesencephalo- 
 spinal tract, or sulco-marginal fasciculus), is composed of axones 
 descending from the anterior corpora quadrigemina (colliculi supe- 
 riores). These fibres immediately commence to decussate ( optic 
 
200 HUMAN ANATOMY 
 
 acoustic reflex path") and as they descend, continue to decussate 
 through the medial raphe on each side of which they lie. During the 
 course of this tract through the pons and medulla many of its fibres 
 terminate in the nuclei of all of the motor cranial nerves, the tract it- 
 self enters the anterior column (funiculus anterior medullas spinalis) 
 of the cord on the side opposite to that of its origin. Continuing down- 
 wards, between the direct pyramidal tract (ventral cerebro-spinal 
 fasciculus) and the anterior medial fissure, its fibres terminate in 
 cells of the anterior horn (columna anterior). 
 
 4. Medial Longitudinal Fasciculus (posterior longitudinal bundle), is 
 composed mostly of short association fibres. It originates in a special 
 nucleus of its own that is situated in that part of the floor of the 3d 
 ventricle which is immediately behind, or above, the corpora albicantia 
 (corpora mammillaria); it passes downwards, close to the mid-line, 
 between the medial lemniscus (medial fillet) and the gray matter 
 (substantia griesea centralis) of the aquaeductus cerebri (Sylvius), 
 where it becomes intimately connected with the nuclei of the 3d, 
 4th, and 6th cranial nerves, and the cells of the anterior corpus quad- 
 rigeminum (colliculus superior) It continues downwards close to the 
 mid-line immediately in front of the gray matter forming the floor of 
 the 4th ventricle where it becomes connected with the nuclei of the 
 7th and vestibular portion of the 8th cranial nerves. It gives off 
 and receives many collaterals in the formatio (substantia) reticularis 
 as it traverses the pons and medulla in order to enter the anterior 
 column (funiculus anterior medullae spinalis) of the cord where its 
 fibres terminate in the cells of the anterior horn (columnae anterior). 
 This tract seems to be made up mostly of fibres which have decussated. 
 Throughout its entire course it always lies close to the mid-line 
 immediately in front of the central gray matter, of whatever structure 
 it traverses. 
 
 5. Spino-thalamic Tract, is composed of direct ascending fibres which 
 transmit sensation of pain, heat and cold, pressure and touch, from the 
 skin on one side of the body to the opposite side of the brain. The 
 sensory end-organs of the skin are connected with the peripheral 
 processes (dendrites) of cells in the ganglia of the posterior roots of 
 the spinal nerves. The central processes (axones) of these cells are 
 connected with cells in the gray matter of the posterior horn (columna 
 posterior) of the cord (medulla spinalis) from which axones pass 
 forwards and cross by way of the anterior white commissure to the 
 opposite side of the cord (medulla spinalis) where they ascend, at 
 first loosely scattered, in the antero-lateral funiculus, they ultimately 
 
THE BRAIN 2OI 
 
 become condensed into a distinct tract or fasciculus which ascends 
 in the lateral side of the medulla, continues upwards through the pons, 
 medial to the olivo-cerebellar and rubro-spinal tracts, then, along 
 with the medial lemniscus, it traverses the tegmentum and the 
 posterior limb (pars occipitalis) of the internal capsule to terminate 
 in the thalamus. 
 
 6. Superior Peduncles (brachia conjunctiva) of the Cerebellum, consists 
 of fibres originating in the dentate nuclei of the cerebellum. They 
 are two white bands, a right and a left, which emerge, widely apart, 
 from the front of the cerebellum. As they run upwards and for- 
 wards they converge forming the lateral boundaries and a small por- 
 tion of the roof of the front or upper half of the 4th ventricle. They 
 join each other in the mid-line, decussate and then pass upwards 
 under cover of the posterior pair of corpora quadrigemina (colliculi 
 inferiores) each one terminating in the red nucleus (nucleus tegmenti 
 ruber) of the side opposite to that of its origin. 
 
 7. Rubro-spinal tract (pre-pyramidal or Monakow's tract), is a 
 descending crossed motor strand which seems to be the downward 
 continuation of some of the fibres of the superior peduncles (brachia 
 conjunctiva) of the cerebellum which having come from the dentate 
 nucleus and crossed to the red nucleus of the opposite side, are by 
 means of the rubro-spinal tract connected to their original side of the 
 spinal cord. The fibres of the rubro-spinal tract originate in the red 
 nucleus (nucleus tegmenti ruber) just beneath the anterior corpus 
 quadrigeminum (colliculus superior) they cross the medial plane to 
 the opposite side, descend close to the lateral lemniscus behind the 
 trapezium in the pons, becoming superficial in the medulla, where 
 they lie in the furrow of the lateral area or pyramid between the olive 
 and the spinal tract of the trigeminal nerve, they enter the lateral 
 column (funiculus lateralis) of the spinal cord (medulla spinalis) 
 where they continue downwards immediately in front of the crossed 
 pyramidal tract (fasciculus cerebro-spinalis lateralis) which is in- 
 vaded by some of the fibres, the others terminating in the cells of the 
 anterior horn (columna anterior). 
 
 8. Descending (Mesencephalic) Root of the Trigeminal Nerve, enters 
 into the composition of the Masticator Nerve (motor portion of the 
 fifth). Its fibres originate in the giant pyramidal cells in the lower 
 part of the somaesthetic (sensory-motor) area of the cerebral cortex. 
 These pyramidal fibres traverse the genu of the internal capsule, 
 continue through the tegmentum, medial to the superior peduncle 
 (brachium conjunctivum) of the cerebellum, then decussate before 
 
202 HUMAN ANATOMY 
 
 terminating in accessory motor nucleus of the fifth nerve. This 
 nucleus is also known as the Mesencephalic Nucleus of the Masticator 
 Nerve, it is a column of gray matter lateral to the gray matter (stra- 
 tum griseum centrale) surrounding the cerebral aqueduct (Sylvius). 
 9. Olivary Fasciculus (thalamo-olivary or central tegmental tract), 
 is composed of fibres that originate both in the lenticular (lentiform) 
 nucleus and the thalamus, traverse the central portion of the tegmen- 
 tum and continue in the pons, behind the medial lemniscus in the 
 formatio reticularis to the inferior olivary nucleus, being continued 
 from the olive to the opposite cerebellar hemisphere by way of the 
 cerebello-olivary fibres. 
 
 Corpora Quadrigemina (colliculi) are 4 rounded eminences placed in 
 pairs, 2 in front and 2 behind, on the dorsal surface of the mid-brain 
 (mesencephalon) immediately behind the 3d ventricle and beneath the 
 posterior border of the corpus callosum. All 4 collectively are often called 
 the Tectum or Tectum Mesencephali, e.g., in names such as u teclo-spinal. n 
 The upper or anterior pair were called the nates (colliculi superiores), the 
 lower pair the lestes (colliculi inferiores). They are connected by 4 bands, 
 the brachia, with the corpora geniculata, those of the anterior corpora 
 quadrigemina (colliculi superiores) being continued directly into the optic 
 tract. They are composed of white matter externally and gray matter 
 internally. The anterior pair contain the 
 
 Stratum Zonale, a thin stratum of white matter on the surface. 
 
 Stratum Cinereum (stratum griseum colliculi superioris), next below, 
 a layer of gray matter. 
 
 Stratum Opticum, the upper gray- white layer, having many fine nerve- 
 fibres intersecting the gray matter. 
 
 Stratum Lemnisci, the deep gray-white layer, consisting of nerve- 
 fibres and nerve-cells of large size. 
 
 Aqueduct of Sylvius, or Her a tertio ad quartum ventriculum (aquaeductus 
 cerebri) is a narrow canal, about ^ inch long, connecting the 3d ventricle 
 with the 4th, and situated between the corpora quadrigemina (colliculi) 
 and the tegmentum. It is surrounded by a layer of gray matter (stratum 
 griseum centrale) which is continuous with the gray matter of the 3d and 
 4th ventricles, and contains groups of cells which are connected with the 
 roots of the 3d, 4th and 5th cranial nerves. 
 
 The Hypo-thalamic Region (right or left), is the forward prolongation 
 of the tegmentum becoming blended with the under surface of the thala- 
 mus, it consists mainly of the upward and forward production of the red 
 nucleus (nucleus tegmenti ruber), medial lemniscus (fillet), and the sub- 
 
THE BRAIN 
 
 203 
 
 stantia nigra which is here expanded laterally by an additional cluster of 
 nerve cells forming the Nucleus Hypothalamicus. 
 
 The Rhombencephalon morphologically comprises: i. isthmus rhom- 
 bencephali, 2. metencephalon, and 3. myelencephalon. 
 
 Isthmus Rhomb encephali (isthmus of the hind-brain) comprises: 
 
 a. Superior Peduncles (brachia conjunctiva) of the cerebellum (see 
 
 page 201). 
 
 b. Superior Medullary Velum (valve of Vieussens) is triangular in shape 
 
 with the apex pointing forwards. It forms the roof of the anterior 
 or upper half of the 4th ventricle by filling up the interval between 
 the two superior peduncles (brachia conjunctiva) of the cerebellum. 
 It consists of a lamina of white matter which is crossed on its upper 
 surface by several transverse bands of gray matter which collec- 
 tively are known as the lingula cerebelli. 
 
 The Metencephalon or the Hind-brain, comprises the pons Varolii, 
 the Cerebellum, and the upper half of the 4th Ventricle. The latter is 
 described with its lower half, under the Medulla Oblongata, in the next 
 section. 
 
 FIG. 73. 
 
 13 
 
 17 
 
 The Pons Varolii (6), is the bond of union of the various parts of the 
 brain, connecting the cerebrum with the cerebellum (3) and the medulla 
 oblongata (9). It is about i^ inch wide and i inch long and thick, and is 
 situated between, the hemispheres of the cerebellum above the medulla 
 oblongata and below the crura (pedunculi) cerebri. It consists of a 
 ventral or anterior portion (pars ventralis) (7), containing layers of trans- 
 
) 
 
 4 
 
 jj 
 
 4 
 
 2CH HUMAN ANATOMY 
 
 verse and longitudinal fibres, also a small quantity of gray matter, a 
 tegmental, dorsal, or posterior portion (pars dorsalis), which is a continua- 
 tion of the reticular formation of the medulla, most of its constituents 
 being continued into the tegmentum of the crura (pedunculi) cerebri. 
 
 The Gray Matter of the Pons consists of the following important 
 collections of nerve-cells: 
 
 Superior Olivary Nucleus (nucleus olivarius superior), an isolated mass 
 
 of gray matter situated on the dorsal surface immediately above the 
 
 inferior olivary nucleus (nucleus olivarius inferior) of the medulla. 
 Nuclei of the $th Nerve 2, one for the motor (12) and one for the sensory 
 
 root (13), the latter external to the former. 
 Nucleus of the 6th Nerve, beneath the floor of the 4th ventricle, close 
 
 to the root of the facial nerve; its fibres pass through the pons and 
 
 emerge at its lower margin (14). 
 Nucleus of the Facial (jth) Nerve, situated deeply below the floor of the 
 
 4th ventricle; its roots follow a tortuous course in the pons, emerging 
 
 at its lower border (15), external to those of the abducent nerve. 
 Nuclei of the Auditory (Sth) Nerve 2, are dorsal and ventral, both lying 
 
 chiefly in the medulla but prolonged into the pons; the roots emerging 
 
 at its lower border (17), in the groove between the olivary body (oliva) 
 
 and the restiform body (corpus restiforme). 
 Nuclei Pontis, small masses of gray matter in the ventral or anterior 
 
 portion of the pons. 
 Substantia Gelalinosa (of Rolando), which is continuous with that of 
 
 the spinal cord and medulla. 
 Locus Cceruleus, a slate-colored bluish spot on the upper part of the 
 
 floor of the 4th ventricle. 
 
 The White Matter of the Pons consists of 4 sets of medullated nerve 
 fibres, superficial transverse, superficial longitudinal, deep transverse and 
 deep longitudinal. 
 
 The Superficial Transverse Fibres, are on the ventral surface of the 
 pons, they continue laterally into the middle peduncles (brachia 
 pontis) of the cerebellum. 
 The Superficial Longitudinal Fibres of the pons comprise, 
 
 1. Upward continuation of the anterior pyramids (ventral area) of 
 the medulla (see page 209). 
 
 2. Cortico-pontine Tracts (see page 197). 
 
 3. Stratum Intermedium or Caudate-cerebellar Tract (see page 197). 
 The Deep Transverse Fibres, form the trapezium (corpus trapezoideum) 
 
 and then pass laterally into the middle peduncles (brachia pontis) 
 
THE BRAIN 205 
 
 of the cerebellum (see lateral lemniscus, page 199, and acoustic nerve, 
 page 220). 
 
 The Deep Longitudinal Fibres, of the pons constitute a portion of the 
 reticular formation in which the following distinct bundles can be 
 traced, 
 
 1. Olivary Fasciculus, Thalamo-olivary or Central Tegmental Tract 
 (see page 202), lies in the reticular formation dorsal to the medial 
 lemniscus. 
 
 2. Descending or Mesencephalic Root of the Trigeminal Nerve (see 
 page 201). 
 
 3. Fasciculus Teres, is composed of fibres of the facial nerve which, by 
 looping upwards behind the nucleus of the abducens nerve and then 
 running forwards and upwards, forms the eminentia teres or medialis 
 (colliculus facialis) which lies in the floor of the anterior or upper 
 half of the 4th ventricle, immediately lateral to the mid-line. 
 
 4. Medial Lemniscus or Fillet (see page 198), which comprises the 
 fasciculus gracilis (column of Goll) and the fasciculus cuneatus 
 (column of Burdach). 
 
 5. Lateral Lemniscus or Fillet (see page 199), composed of the cochlear 
 fibres of the central auditory path. 
 
 6. Ventral Longitudinal or Sulco-marginal Fasciculus (Tecto-spinal 
 or Mesencephalo-spinal Tract) (see page 199). 
 
 7. Medial Longitudinal Fasciculus (Posterior Longitudinal Tract) 
 (see page 200). 
 
 8. Rubro-spinal Fasciculus (Pre-pyramidal or Monakow's Tract) (see 
 page 201). 
 
 9. Ascending Antero-lateral Tract of Cowers, comprises a direct 
 and an indirect path through which sensation of pain, temperature, 
 pressure, and touch reaches the brain. 
 
 a. Spino-thalamic Tract is the direct path (see page 200). 
 
 b. Ventral Spino-cerebellar Tract (Superficial Ventro-lateral 
 Spino-cerebellar Fasciculus) is the indirect path. The term 
 "Cowers' Tract" is limited by some to this tract only. It 
 originates in the following way, the sensory end organs are con- 
 nected with the peripheral processes (dendrites) of cells in the 
 ganglia of the posterior roots of spinal nerves, the central proc- 
 esses (axones) of these cells are connected with cells in the 
 base of the lateral horn (columna lateralis), known as"Stillings' 
 Nucleus," and with cells in the lateral horn (columna lateralis) 
 of the spinal cord (medulla spinalis). The axones of these cells, 
 both of the same and the opposite side, are agminated into a 
 
206 HUMAN ANATOMY 
 
 bundle, the Ventral Spino-cerebellar Tract (Superficial Ventro- 
 lateral Spino-cerebellar Fasciculus) which travels upwards in the 
 lateral column (funiculus lateralis) of the spinal cord (medulla 
 spinalis). It maintains this position as it traverses the medulla 
 until it reaches the pons where it runs forwards and upwards as 
 high as the level of the trigeminal nerve, it then runs backwards 
 and downwards, enters the superior peduncle (brachium conjunc- 
 tivum) of the cerebellum, and terminates in the lingula of the 
 superior vermis cerebelli of its own side. 
 
 The Cerebellum consists of gray matter (substantia corticalis) on the 
 surface and white matter (corpus medullare) in the interior. Its surface 
 is not convoluted like that of the cerebrum, but is traversed by curved 
 fissures and furrows (sulci), the latter separating the laminae (folia or gyri) 
 of which it is composed. It lies in the inferior occipital fossae of the skull, 
 beneath the occipital lobes of the cerebrum, from which it is separated by 
 a process of dura mater, the tentorium cerebelli. It is divided into a cen- 
 tral portion or lobe, the Vermis Cerebelli or Vermiform Process (i), and two 
 lateral Hemispheres; all continuous with each other and- substantially the 
 same in structure. It presents the following primary fissures: 
 Great Horizontal Fissure (10), horizontally round the free margin, 
 from the pons in front to the median line behind, giving origin to the 
 secondary fissures. 
 Incisura Cerebelli Anterior, or Anterior Cerebellar Notch, a broad, 
 
 shallow, vertical notch, separating the hemispheres in front. 
 Incisura Marsupialis (2), or Posterior Cerebellar Notch, a deep notch, 
 
 separating the hemispheres from each other behind. 
 Vallecula, a deep depression on the inferior surface, containing the 
 
 lower extremity of the vermis (vermis inferior). 
 
 Secondary Fissures of the Cerebellum are 8 in number, 4 superiorly and 
 4 inferiorly. They pass in a curved direction from side to side across the 
 cerebellum, beginning (except one) and ending in the great horizontal 
 fissure. They are named from before backward as follows: 
 On the upper surface of the cerebellum, the 
 
 Pre-central. Post-central. Anterior Semilunar or Pre-clival. 
 
 Posterior Semilunar or Post-clival. 
 On the lower surface of the cerebellum, the 
 
 Post-nodular. Retro-tons illar or Pre- pyramidal. 
 
 Anterior Inferior or Post-pyramidal. Posterior Inferior or Post-gracile. 
 The post-gracile is a branch of the post-pyramidal, and ends in the 
 great horizontal fissure. 
 
THE BRAIN 207 
 
 Lobes of the Cerebellum. The 3 primary lobes, the Vermis or Worm 
 and the Hemispheres, are divided by the above-named secondary fissures 
 into 19 lobes, named as follows: 
 
 On the upper surface of the Worm (vermis superior), from before 
 backward 5, the 
 
 Lingula. Lobulus Centralis. Culmen Monticuli. 
 
 Diclive or Clivus Monticuli. Folium Cacuminis or Commissura Simplex. 
 On the upper surface of the Hemispheres, from before backward 5, the 
 Vinculum Lingualce or Freenulum. Ala Lobuli Centralis. 
 
 A nterior Semilimar or Crescentic Lobe. Posterior Semihmar or 
 
 Crescentic Lobe. 
 
 Superior Semilunar or Posterior Superior Lobe. 
 On the lower surface of the Worm, from before backward 4, the 
 
 Nodule. Uvula. Pyramid. Tuber Valvula. 
 
 On the lower surface of the Hemispheres, from within outward 5, the 
 Flocculus (5). Tonsil or Amygdala (4). Biventral Lobe (3). 
 Cradle or Slender Lobe (3). Inferior Semilunar Lobe (3). 
 
 White Matter (Corpus Medullare) of the Cerebellum includes the 
 peduncular fibres and the fibres proper. The former are projection fibres 
 and are arranged in 3 peduncles on each side, which arise from the anterior 
 part of the hemispheres, and connect the cerebellum with itself and with 
 the rest of the brain, as follows: 
 
 Superior Peduncles (brachia conjunctiva), in part form the roof of 
 the 4th ventricle; they pass from the corpus dentatum under the 
 corpora quadrigemina, below which their fibres decussate, going to 
 the red nucleus of the tegmentum, and by a relay through the optic 
 thalamus to the cerebral cortex. Stretching from one peduncle to 
 the other is the 
 
 Valve of Vieussens, or Superior Medullary Velum (see page 203), a 
 
 thin lamina of white matter, which with the superior peduncles forms 
 
 part of the roof of the 4th ventricle (see page 211). 
 
 Middle Peduncles (brachia pontis) (8), comprise most of the transverse 
 
 fibres of the pons, and are chiefly commissural fibres connecting the 
 
 cerebellar hemispheres with each other. All are connected with the 
 
 nucleus pontis of the same or the opposite side, those that are not 
 
 commissural are the continuation of the cortico-pontine tracts (see 
 
 page 197). 
 
 Inferior Peduncles (corpora restiformes), connect the cerebellum 
 
 with the medulla oblongata. 
 Fibra Proprice, the proper fibres of the cerebellum, are of 2 kinds; the 
 
208 HUMAN ANATOMY 
 
 commissural, connecting the hemispheres, and the association or 
 arcuate fibres, connecting adjacent laminae. 
 
 Cortical Gray Matter (Substantia Corticalis) of the Cerebellum is 
 situated on the surface, forming the cortex, a section of which presents a 
 characteristic foliated appearance, named the Arbor Vita, due to the 
 branching of the laminae given off from the central white matter to the 
 cortical portion. The gray matter of the cortex consists of three layers, 
 as follows: 
 
 Molecular or External Gray Layer, consists of fibres and cells. 
 Middle Layer Containing the Cells of Purkinje, (the characteristic cells 
 of the cerebellum), an incomplete stratum of flask-shaped cells, their 
 bases resting on the granular layer, their necks giving off numerous 
 dendrites to the molecular layer. 
 
 Granular or Internal rust-colored Layer of Turner, contains numerous 
 small nerve-cells or granules of reddish-brown color, also many nerve- 
 fibrils, among which are the axones of the Purkinje cells. This layer 
 also contains larger cells, known as the Golgi cells, situated in its outer 
 part. 
 
 Central Gray Matter of the Cerebellum is disposed on each side in 4 
 centres, one of which, the dentate nucleus is large; the others being of small 
 size. They are situated in the middle of the white matter of the organ, and 
 are as follows: the 
 
 Dentate Nucleus, or Ganglion of the Cerebellum, an irregularly folded 
 lamina of gray matter, having an opening anteriorly, the hilum, from 
 which emerge most of the fibres of the superior peduncle (brachium 
 conjunct! vum.) 
 
 Nucleus Emboliformis, lies to the inner side of the dentate nucleus, 
 partly covering its hilum. It is probably part of the dentate nucleus. 
 Nucleus Globosus, an elongated mass on the inner side of the preceding. 
 Nucleus Fastigii, or Roof Nucleus of Stilling, is close to the middle line 
 at the anterior end of the vermiform process (vermis) and imme- 
 diately over the roof of the 4th ventricle. The fibres of the ves- 
 tibular nerve terminate in this nucleus after having decussated in the 
 vermis. 
 
 THE MEDULLA OBLONGATA 
 
 The Medulla Oblongata, or Myelencephalon, formerly called the Spinal 
 Bulb, is thelowermost division of the brain and is continuous with the spinal 
 cord. It extends from the lower margin of the pons Varolii (5) to the 
 inferior pyramidal (motor) decussation (12) corresponding to the lower mar- 
 gin of the foramen magnum. Its ventral surface rests on the basilar 
 
THE BRAIN 209 
 
 groove of the occipital bone, its dorsal surface is in the fossa between the 
 cerebellar hemispheres. It is i inch long, % inch broad above, and ^ inch 
 thick; and of pyramidal form, its broad end upward. On its surface are 
 the anterior and posterior median fissures; the former terminating just 
 below the pons in a cul-de-sac, the foramen ccecum; the latter expanding 
 into the 4th ventricle about the middle of the medulla. On each side the 
 medulla presents the following parts: 
 
 Pyramid (7), a bundle of white matter alongside the anterior median 
 fissure, formed by the upward continuation of the direct tract (fas- 
 ciculus cerebro-spinalis anterior) of the anterior column (funiculus 
 anterior) and the crossed tract (fasciculus cerebro-spinalis lateralis) 
 of the lateral column (funiculus lateralis) of the spinal cord. As the 
 latter tract ascends it decussates with its fellow of the opposite side 
 across the fissure, forming the inferior decussalion of the pyramids 
 (8). Each pyramid is bounded by the antero-lateral sulcus which is 
 continuous with that of the cord. 
 
 Olive (Olivary Body) (9), an ovoid projection on the outer side of the 
 pyramid and immediately below the pons. In the groove between the 
 olive and pyramid, the hypoglossal nerve fibres (27) emerge; in that 
 between the olive and restiform body (inferior cerebellar peduncle) 
 emerge the glosso-pharyngeal 
 (24), pneumogastric (n. vagus) 
 (25) and spinal accessory (n. 
 accessorius) (26) nerves. The 
 Inferior Olivary Nucleus or corpus 
 denlatum is a thin, wavy lamina 
 of gray matter, open at its upper 
 and inner part. Three accessory 
 nuclei (dorsal, medial and 
 lateral) are also situated in the 
 olive. 
 
 Fasciculus of Rolando (10), a 
 slight, longitudinal prominence 
 on the outer side of the olivary 
 body. It corresponds to a mass 
 
 of gray matter, substanlia gelatinosa, continuous with the posterior 
 horn of the gray matter of the cord. 
 
 Lateral Column, hidden above by the olivary body but showing below 
 it; is the continuation of the lateral column (funiculus lateralis) of 
 the cord in part. 
 
 Restiform Body (inferior cerebellar peduncle), between the lateral 
 14 
 
210 HUMAN ANATOMY 
 
 column and the fasciculus cuneatus; contains the arcuate fibres, 
 external and internal, and the dorsal spino-csr Cellar fasciculus (direct 
 cerebellar tract). The two restiform bodies diverge as they ascend, 
 assist in forming the lateral walls of the 4th ventricle, and enter the 
 cerebellar hemispheres as the inferior peduncles of the cerebellum. 
 
 Dorsal S pino-cerebellar Fasciculus (direct cerebellar tract of Flechsig), 
 arises from cells in the dorsal nucleus (Clark's column) which occu- 
 pies the base (cervix) of the posterior horn (columna posterior) of 
 the cord from the level of the 3d lumbar to that of the 7th cervical 
 nerve. The axones arising in these cells pass to the dorso-lateral 
 periphery of the lateral column (funiculus lateralis) up which they 
 continue until they reach the medulla, then they run up behind the 
 origins of the Qth, loth and nth cranial nerves, and then bend out- 
 wards and forwards, entering the restiform body (inferior cerebellar 
 peduncle) in which they continue to the cells in the cortex of the 
 cerebellar hemisphere of th2 same side as that of their origin. 
 
 External or Superficial Arcuate Fibres, are in two sets. The anterior set 
 of fibres are the more numerous, they arise from cells in the nucleus 
 gracilis and nucleus cuneatus, run forwards, and decussate in the medial 
 raphe, emerge in the anterior medial fissure and run outwards across 
 the surface of the pyramid and lower part of the olive, then turn 
 upwards and enter the restiform body (inferior cerebellar peduncle) of 
 the side opposite to that of their origin. 
 
 The posterior set of fibres also arise from the cells in the cuneate and 
 gracile nuclei; they run outwards, forwards, and upwards directly into 
 the restiform body (inferior cerebellar peduncle) of the same side as 
 that of their origin. 
 
 Internal or Deep Arcuate Fibres form an intricate network situated 
 between the olives and behind the pyramids. Some of these fibres, 
 the olivo-cerebellar and cerebello-olivary : , enter the restiform body (infe- 
 rior cerebellar peduncle) . The remaining fibres are association or com- 
 missural fibres connected with the nuclear cells in the formatio 
 reticularis of the tegmentum and the nuclei of the sensory cranial 
 nerves. 
 
 Fasciculus Cuneatus, between the restiform body and the funiculus 
 gracilis; is the continuation of the postero-lateral column of the cord 
 (see lateral lemniscus, page 198). 
 
 Fasciculus Gracilis (posterior pyramid), a narrow, white band, parallel 
 to and alongside the posterior fissure; is the continuation of the pos- 
 tero-median column of the cord. Its enlarged upper extremity is 
 club-shaped and called the clava (see lateral lemniscus, page 198). 
 
THE BRAIN 211 
 
 Other Structures in the Medulla. Internally the medulla is composed 
 of longitudinal bundles of nerve-fibres, masses of gray matter constituting 
 nerve nuclei, and nerve-fibres originating from the nuclei. The 
 
 Independent Nuclei, are those of the 5th, 8th, gih, loth, nth and i2th 
 cranial nerves, which arise in or near the floor of the 4th ventricle; 
 also the nucleus of the fasciculus teres (eminentia medialis or teres), 
 that of the olivary body, the accessory olivary nuclei, and the tractus 
 solitarius or trineural tract, the ascending root of the gth nerve. 
 Raphe or Medial Septum, is situated in the middle line of the medulla 
 above the decussation of the pyramids, and consists of fibres having 
 different directions and of multipolar nerve-cells. 
 
 Formatio Reticularis, is a coarse network, situated within the anterior 
 and lateral regions of t^e medulla, and is formed by the breaking up of 
 the anterior gray matter by the white fibres of the crossed pyramidal 
 (cerebro-spinal) tracts. 
 
 The Fourth Ventricle, or Ventricle of the Cerebellum, is a diamond- 
 shaped cavity lying between the cerebellum and the posterior surface of 
 the pons Varolii and medulla oblongata. Its upper angle is on a level with 
 the upper border of the pons, it corresponds with the lower opening of the 
 cerebral aqueduct of Sylvius, by which this ventricle communicates with the 
 3d ventricle. Its lower angle is on a level with the lower border of the 
 olivary body (oliva), it is continuous with the central canal of the spinal 
 cord, and is called the calamus scriptorius, from its resemblance to the 
 point of a pen. The ventricle is closed posteriorly by a layer of pia mater, 
 the tela choroidea inferior, with its choroid plexuses, in which layer are 3 
 openings; the foramen of Magendie (metapore), just above the calamus 
 scriptorius in the median line, and the foramina of Key and Retzius at the 
 extremities of the lateral angles. Through these foramina the ventricles of 
 the brain communicate with the subarachnoid space of the brain and 
 spinal cord. The fourth ventricle is bounded as follows: 
 
 Roof, is tent-shaped and formed by superior peduncles of the cere- 
 bellum, the superior medullary velum or valve of Vieussens, the tela 
 choroidea inferior (see above) and its choroid plexus, the obex, and the 
 inferior medullary velum. 
 
 Floor, is formed by the posterior surface of the pons above and the 
 medulla below. It contains the median furrow, on each side of which 
 are the fasciculus teres (eminentia medialis or colliculus facialis), 
 striae acusticae (striae medullares), conductor sonorus (striae obliquae), 
 fovea superior, fovea inferior, alacinerea, tuberculum acusticum, locus 
 caeruleus, taenia violacea, and the eminences of origin of certain nerves 
 (seepages 212 and 213). 
 
212 HUMAN ANATOMY 
 
 Laterally, in the upper part are the superior peduncles of the cere- 
 bellum; in the lower part, the inferior peduncles (restiform bodies) 
 fringed by the funiculi graciles, their clavae and the ligulae. 
 
 Parts named above, and heretofore undescribed, are the 
 
 Sulcus Longitudinalis Medianus, the vertical median fissure; from the 
 centre of which on each side emerge the 
 
 Strife Medullares or Stria Acusticce, white fibres crossing the floor of 
 the ventricle transversely, dividing it into two triangles, and passing 
 outward to the auditory nerve. They are the axons of the nerve- 
 cells of the tuberculum acusticum. 
 
 Conductor Sonorus (striae obliquae), a whitish band of fibres in no way 
 differing from the striae medullares except that they run from the mid- 
 line obliquely outward and forward instead of transversely. They 
 are not constant. 
 
 Inferior Medullary Velum, a thin layer of white matter, stretching over 
 the ventricle toward its lateral angles. 
 
 Obex and Lingula,<are, respectively the inferior and superior parts of a 
 little irregular ridge, which runs from the clava of the funiculus gracilis 
 to its fellow of the opposite side. 
 
 Eminentia Teres (colliculus facialis), the prominent centre of a spin- 
 dle-shaped eminence made by an underlying bundle of white fibres, 
 the fasciculus teres, formed in part by the fibres of the facial nerve. 
 
 Fovea Superior, an angular depression, external to the fasciculus teres 
 and above the striae medullares. 
 
 Locus Cceruleus, a bluish depressed area above the fovea superior. 
 
 Fovea Inferior, an angular groove, its apex at the striae, its limbs diverg- 
 ing below, enclosing the 
 
 Ala Cinerea or Trigonum Vagi, a triangular area, corresponding with 
 the nuclei of the vagus and glosso-pharyngeal nerves. 
 
 Eminentia Cinerea, a prominent elevation of the ala cinerea. 
 
 Trigonum Hypoglossi, a triangular area, internal to the inner limb of 
 the fovea inferior, and corresponding to the tract of nerve-cells from 
 which the hypoglossal nerve originates. 
 
 Trigonum Acustici, a triangular area, external to the outer side of the 
 fovea inferior, having at its base a prominence, the tuberculum 
 acusticum, 
 
 Nuclei of Origin, in the floor of the 4th Ventricle, comprise the nuclei of 
 the cranial nerves from the 5th to the i2th inclusive, also vaso-motor, 
 cardiac ancj respiratory centres, Near the ventricle, in the anterior wall 
 
THE SPINAL CORD 21^ 
 
 of the aqueduct of Sylvius, are the nuclei for the 3d and 4th nerves. 
 Those in the floor itself are as follows: 
 
 $lh Nerve (trigeminus), two groups of cells, extending the length of the 
 
 medulla and alongside the aqueduct of Sylvius, the nuclei lying close to 
 
 the lateral recesses of the ventricle. 
 
 6th Nerve (abducens), in the upper part, close to the median line. 
 ^th Nerve (facial), below and external to the 6th. 
 8th Nerve (auditory), 2 nuclei, one beneath the striae, the other just 
 
 outside the ventricle. 
 gth Nerve (glosso-pharyngeal) and loth Nerve (vagus), in the upper part 
 
 of the ala cinerea, near the inferior angle of the ventricle. 
 nth Nerve (spinal accessory), below the preceding, in the lower part of 
 
 the ala cinerea, and running down into the cord as low as the 6th cer- 
 vical vertebra. 
 1 2th Nerve (hypoglossal) , internal to the gth and loth beneath the 
 
 fasciculus teres, and in the trigonum hypoglossi. 
 
 THE SPINAL CORD (MEDULLA SPINALIS) 
 
 The Spinal Cord is that part of the cerebro-spinal axis which is situated in 
 the spinal canal. Its length is about 17 or 18 inches, terminating at the 
 lower border of the ist lumbar vertebra in thefilum terminate (16). It is 
 cylindrical in general form, with 2 enlargements, one in the cervical region, 
 the other in the lumbar. It is composed of gray and white matter, the 
 gray being inside (instead of outside, as in the cerebrum), and arranged so 
 as to present a crescentic appearance in horizontal section, joined by a 
 transverse commissure, and the extremities forming the Anterior and Pos- 
 terior Horns (columnae), from which regions respectively the anterior and 
 posterior roots of the spinal nerves have their apparent origin. The 
 Membranes, of the cord are 3, as in the brain: the dura mater, arach- 
 noid, and pia mater. The Dura Mater represents only the meningeal 
 or supporting layer of the cranial dura mater. It is not adherent to 
 the spinal column, but is connected thereto by fibrous tissue. The 
 Arachnoid is arranged as on the brain, its sub-arachnoid space being 
 filled with its fluid, for the protection of the cord. The Pia Mater has 
 a fibrous band on each side, the ligamentum denticulatum (9), con- 
 necting it to the dura mater by 21 serrations. 
 Fissures, number 6, the anterior and posterior median, and on each 
 
 side the postero-lateral (n) and the posterior intermediate. 
 Columns (funiculi), are 4 in number, 2 on each side of the cord; a 
 small posterior column, and a large antero-lateral column, separated 
 from each other by the postero-lateral fissure. The posterior col- 
 
214 
 
 HUMAN ANATOMY 
 
 FIG. 75- 
 
 umn is further divided in its upper part, into a postero-median and a 
 postero-lateral column, which are separated from each other by the 
 posterior intermediate septum. 
 
 Central Canal, a minute canal, barely visible to the naked eye, extends 
 the whole length of the cord, originating above 
 in the lower angle of the 4th ventricle (i) and 
 terminating below in a somewhat dilated 
 extremity. 
 
 White Substance of the Cord consists of medul- 
 lated fibres, mostly disposed longitudinally, but 
 some obliquely and transversely, also blood-vessels 
 and neuroglia. The Neuroglia supports the fibres 
 and cells of the gray substance as well as the fibres 
 of the white, and is accumulated in three situa- 
 tions; on the surface of the cord, beneath the pia 
 mater; around the central canal, as the substantia 
 gelatinosa centralis; as a cap over the posterior 
 horn of gray matter, forming the substantia cinerea 
 gelatinosa. 
 
 Nerve-tracts in the white substance of the cord, 
 shown by investigation of pathological lesions, as 
 extending along various portions of the cord and 
 into or from the brain, are 8 in number, as 
 follows: 
 
 In the antero-lateral column (funiculus antero- 
 lateralis) are 6, the 
 
 Direct Pyramidal Tract (fasciculus cerebro- 
 spinalis anterior), next to the median fissure 
 and in the upper part of the cord; consists 
 of descending fibres from the motor area of 
 the cerebral cortex of the same side, passing 
 
 through the pyramid of the medulla, crossing in the anterior white 
 commissure of the cord, and disappearing about the middle of its 
 thoracic region (see page 196). 
 
 Crossed Pyramidal Tract (fasciculus cerebro-spinalis Jateralis), in the 
 hinder part of the column; consists of descending fibres from the 
 motor area of the cortex on the opposite side, through the pyramid 
 of the medulla, crossing in the decussation of the pyramids (see 
 page 196). 
 Antero-lateral Ascending (Gower's) Tract (anterior spino-cerebellar 
 
THE SPINAL CORD 215 
 
 fasciculus), in the anterior part of the column; consists of ascending 
 fibres arising from cells in the posterior horn, crossing in the anterior 
 gray commissure, and passing upward through the medulla and pons 
 to the cerebellum through its superior peduncles (brachia conjunc- 
 tiva) (see page 205). 
 
 Direct Cerebellar Tract (dorsal spino-cerebellar fasciculus), behind 
 the preceding, commencing in the lumbar region; consists of fibres 
 from cells in the posterior gray matter, ascending through the resti- 
 form body to the cerebellum (see page 210). 
 
 Tract of Lissaucr (fasciculus postero-lateralis) a small tract, formed by 
 some of the fibres of the posterior roots of the spinal nerves, running 
 upward for a short distance and entering the posterior horn of gray 
 matter. 
 
 Antero-lateral Ground Bundle (fasciculus proprius anterior et fas- 
 ciculus proprius posterior), is the remaining part of the column, 
 situated next to the gray matter of the cord; contains longitudinal 
 association fibres, uniting cell-groups of the gray matter with each 
 other; fibres crossing the anterior commissure from the gray matter 
 of the opposite side; horizontal fibres belonging to the anterior roots of 
 the spinal nerves. 
 In the Posterior Column (funiculus posterior) are 2 tracts, the 
 
 Tract of Goll (fasciculus gracilis), next to the posterior fissure; con- 
 sists of fibres from the posterior roots of the spinal nerves, ascend- 
 ing to the medulla where they end in the nucleus gracilis (see page 
 198). 
 
 Tract of Burdach (fasciculus cuneatus), between the preceding and 
 the gray matter; consists of fibres from the posterior roots of the spinal 
 nerves, some ascending a short distance and entering the gray matter, 
 others entering Coil's tract and passing to the medulla (see page 
 198). 
 
 Gray Substance of the Cord occupies the central portion, a transverse 
 section showing it in the form of two crescents joined by the gray commis- 
 sure (commissura grisea). Each crescent has an anterior and a posterior 
 cornu or horn (columna) ; a lateral horn being also seen in the upper thoracic 
 region. The gray substance consists of nerve-fibres, nerve-cells, blood- 
 vessels and connective tissue. The 
 
 Nerve-fibres, are found as a dense interlacement of minute fibrils, 
 formed of the axons and dendrons of the nerve-cells and nerves of 
 larger size. 
 
 Nerve-cells* some form columns of cells placed longitudinally, and 
 some are scattered throughout the gray matter. 
 
2l6 
 
 HUMAN ANATOMY 
 
 FIG. 76. 
 
 Clarke's Posterior Vesicular Column (nucleus dorsalis), is a group of 
 nerve-cells at the base of the posterior horn on its inner side, extend- 
 ing from the yth cervical nerve to the 3d lumbar. 
 
 The Spinal Nerves are transmitted from each 
 side of the spinal cord through the intervertebral 
 foramina of the spinal column, in 31 pairs, of 
 which the cervical number 8, the thoracic 12, the 
 lumbar 5, the sacral 5, and the coccygeal i. 
 Each nerve arises by two roots; an anterior (13) 
 or motor root, and a posterior (10) or sensory 
 root, the latter being distinguished by a ganglion, 
 the spinal ganglion (12). These nerves are de- 
 scribed separately infra, after the description of 
 the cranial nerves. The 
 
 Cauda Equina (ly) (horse's tail), is a sheaf of 
 nerves composed of the elongated roots of 
 the 4 upper sacral nerves, passing downward 
 to reach their respective foramina of exit 
 from the spinal canal. 
 
 THE CRANIAL NERVES (NERVI 
 CEREBRALES) 
 
 The Cranial Nerves number 12 pairs, those 
 from the 5th to the i2th inclusive having their 
 deep origin wholly or in part from the floor of the 
 4th ventricle, and all, except the first two, origi- 
 nating in or near that situation. Their super- 
 ficial or apparent origin is their connection with 
 the surface of the brain, their deep or real origin lies 
 in some special nucleus of gray matter deeply 
 
 situated in the brain. After emerging from the surface the nerves pass 
 through tubular prolongations of the dura mater in various foramina at 
 the base of the skull, to their final distribution. 
 
 1st Nerve, Olfactory (n. olfactorius) (Plate 6), nerves of smell (fila), 
 about 20 in number, composed of non-medullated fibres, arise from the 
 under surface of the olfactory bulb (see page 188); deeply by 2 white roots, 
 the medial root from the area of J3roca and the ^callosal and sub-callosal 
 gyrus; the lateral root from the anterior perforated space (substantia 
 perforata anterior) and from the union of the temporal and uncinate gyri, 
 
THE CRANIAL NERVES 
 
 217 
 
 and by the middle gray root (trigonum olfactorium) from thej3ptic thala- 
 by numerous foramina in the cribriform plate of the ethmoid 
 bone; to form a plexiform network over the upper third of the nasal septum, 
 the superior turbinal process and the adjacent surface of the ethmoid 
 bone, from which branches are distributed to the Schneiderian membrane 
 of the nose. 
 
 2d Nerve, Optic (n. opticus) nerve of sight (Plate 6), arises from the 
 optic commissure (chiasma opticum) (16) and tracts (15); deeply from the 
 external geniculate body (corpus 
 geniculatum laterale), the pulvinar 
 of the ojytk: thalamus, and the upper 
 quadrigi-minal body (colliculus su- 
 perior) these being the lower visual 
 centres; also from the^neate and 
 lingual lobules of the occipital lobe 
 (cortical visual centres); exit by the 
 optic foramen; to the retina of the 
 eye. [This nerve and the optic tract 
 are more fully described under the 
 sub-title Nerves of the Eye.] 
 
 20. 
 
 3d Nerve, Motor Oculi (n. oculo- 
 motorius) (Plate 6), motor nerve of 
 the eye-ball,-^omes from the inner 
 side of the crus (peduncle) cerebri 
 (17), in front of the pons (5); deeply 
 from a nucleus in the floor of the 
 aqueduct of Sylvius (aquaeductus 
 cerebri) ; exit by the sphenoidal (su- 
 perior orbital) fissure; to all the mus- 
 cles of the orbit except the superior 
 oblique and external rectus, also 
 
 through the ciliary ganglion to the sphincter of the iris and the ciliary 
 muscle. 
 
 4th Nerve, Trochlear or Pathetic (n. trochlearis) (Plate 6), motor of 
 the eye-ball, arises from the outer side of the crus (jpeduncle) cerebri (18), 
 in front of the pons; deeply from a nucleus in the floor of the aqueduct of 
 .Sylvius, below that of the 3d nerve decussates in the superior medullary 
 velum with its companion nerve \jgU by the sphenoidal (superior orbital) 
 fissure; to the superior oblique (trochlear) muscle of the eye-ball of the side 
 opposite to that of its origin. 
 
218 
 
 HUMAN ANATOMY 
 
 5th Nerve, Trifacial or (n. trigeminus) (Plate 7), nerve of sensation 
 and motion, arises by 2 roots (19) from the side of the pons Varolii; deeply 
 from a nerve-tract in the medulla oblongata and the locu^caeruleus (sen- 
 sory root), the floor of the 4th ventricle and the wall of the cerebral aque- 
 duct of Sylvius (motor root or masti- 
 cator nerve); exit in 3 divisions by 
 the sphenoidal fissure, the foramen 
 rotundum and the foramen ovale 
 respectively. The Gasscrian or semi- 
 lunar ganglion (5) is situated on its 
 sensory root at the origin of the 
 three divisions. This nerve resem- 
 bles a spinal nerve in arising by two 
 roots, in having a ganglion on its pos- 
 terior (sensory) root, and in its com- 
 pound function. It is the great sen- 
 sory nerve of the head and face, 
 and the motor nerve of the muscles 
 of mastication. Its divisions are 
 the ophthalmic, the maxillary and 
 the mandibular as follows: 
 
 OPHTHALMIC (n. ophtf almicus) 
 (6), a sensory nerve, exit by the 
 sphenoidal (superior orbital) fissure; 
 to the eye-ball, lacrimal gland, mu- 
 cous lining of the eye and nasal fossae, and the skin of the forehead, eye- 
 brow and nose. Its branches are the 
 
 Frontal (9) 
 
 Nasal (n) 
 or naso- 
 ciliary 
 
 f Supra-orbital. 
 
 \ Supra-trochlear. Lacrimal (10) 
 
 Branches to the gland, 
 the conjunctiva, and 
 the eyelid. 
 
 Ganglionic, to the ciliary ganglion. 
 
 Ciliary, to the ciliary muscles, iris and cornea. 
 
 Infra-trochlear, to the skin of the eyelids and side of the 
 
 nose, the conjunctiva, lacrimal sac and caruncula 
 
 lacrimalis. 
 
 MAXILLARY (7), a sensory nerve, exit by the foramen rotundum; to 
 the temple, cheek, lower eyelid, nose, lip, upper teeth and the spheno- 
 palatine ganglion, thence to the palate. Its branches are the 
 
THE CRANIAL NERVES 2IQ 
 
 Meningeal (n. meningeus medius). 
 
 f Temporal (ramus zygomaticotem- 
 Orbital (n. zygomaticus) (20) ( poralis). 
 
 [ Malar (ramus zygomaticofacialis). 
 
 2 Spheno- palatine (nn. sphenopalatini). 
 
 2 Posterior Sup. Dental (16) (rami alveolares superiores posteriores). 
 
 Middle Superior Dental (ramus alveolaris superior medius). 
 
 Anterior Sup. Dental (18) (ramus alveolaris superior anterior). 
 
 Palpebral (rami palpebrales inferiores). 
 
 Nasal (rami nasales interni). 
 
 Labial (rami labiales superiores). 
 
 MANDIBULAR (8), includes the masticator nerve or motor root of the 5th, 
 and is a nerve of motion, common sensation and special sense (taste). Its 
 exit is by the foramen ovale. Its recurrent branch goes to the dura 
 mater and the lining of the mastoid cells; its motor filaments to the muscles 
 of mastication; its sensory ones to the teeth and gums of the lower jaw, the 
 skin of the temple and external ear, the lower face and lip, and the anterior 
 % of the tongue. Its branches are the 
 
 Recurrent or meningeal (n. spinosus). 
 Internal Pterygoid (masticator). 
 Masseteric (masticator). Auriculo-tem- 
 Deep Temporal 2 (masticator), poral (26) 
 Buccal (n. buccinatorius). 
 External Pterygoid (masticator). 
 
 Br. to the facial nerve. 
 
 Br. to otic ganglion. 
 
 Ant. Auricular 2. 
 
 Brs. to meatus auditorius 2 
 
 Articular. 
 
 Parotid. 
 
 Superior Temporal. 
 
 Lingual or Gustatory (23), to the tongue, mouth, gums and sub-lingual 
 gland: communicates with the facial, inferior dental and hypoglossal 
 nerves and the sub-mandibular ganglion. 
 
 I Mylo-hyoid (masticator) (28), to that muscle 
 Inferior alveolar or and digastric. 
 
 Dental (24) { Dental Brs. to the molar and bicuspid teeth. 
 
 Incisive, to the canine and incisor teeth. 
 Mental (25), to the chin and lower lip. 
 
 6th Nerve, Abducent (n. abducens) (Plate 10), motor of the eyeball, 
 arises from the pyramid of the medulla oblongata, close to the pons (20, Fig. 
 76); deeply from the floor of the 4th ventricle, beneath the eminentia teres; 
 exit by the sphenoidal (superior orbital) fissure; to the external rectus 
 muscle of the eyeball. 
 
22O HUMAN ANATOMY 
 
 yth Nerve, Facial, Portio Dura (n. facialis) (Plate 8), is the motor nerve 
 of the face, the stapedius, the muscles of the external ear and other mus- 
 cles. The Pars intermedia (glosso-palatine nerve) is a sensory nerve to the 
 palate and its chorda tympani branch is the nerve of taste for the anterior 
 2 a of the tongue, and the vaso-dilator of the sub-mandibular and sub- 
 lingual glands. Cashes, from the upper part of the medulla oblongata, in 
 the groove between the olivary and restiform bodies (21, Fig. 76) ; deeply in 
 the floor of the 4th ventricle, from a nucleus in the lower part of the pons 
 near that of the 6th nerve; the Pars Intermedia takes its deep origin from 
 the Solitary Tract; exit by the internal auditory meatus, through the 
 aqusductus (canalis facialis) Fallopii and the stylo-mastoid foramen; to 
 the muscles of expression of the face, those of the ear, etc., and to the 
 tongue. Behind the ramus of the jaw its diverging branches form the pes 
 anserinus or goose's foot. It communicates with the meningeal sympa- 
 thetic plexus by the external superficial petrosal nerve; with the spheno- 
 palatine and otic ganglia, by the large and small superficial petrosal nerves ; 
 with the auditory, great auricular, auriculo-temporal, pneumogastric (n. 
 vagus), glosso-pharyngeal, small occipital, and superficial cervical nerves, 
 the three divisions of the 5th nerve, and the carotid plexus. The petrosal 
 nerves mentioned above are given off by the geniculate ganglion, a swelling 
 on the ;th nerve in the aquaeductus (canalis facialis) Fallopii (described 
 separately). Its branches of distribution are the 
 
 Tympanic, to the stapedius muscle. 
 
 Chorda Tympani, nerve of taste, etc. (see above). 
 
 Posterior Auricular, dividing into Auricular and Occipital. 
 
 Digastric, to that muscle. 
 
 Stylo-hyoid, to that muscle. 
 
 j Temporal Brs. to the temporal region. 
 
 Temporo-facial { Malar Brs. to the occip.-frontalis and the lower eyelid. 
 [ Infra-orbital / Superficial Brs. 
 \ Deep Brs. 
 
 {Buccal Brs. to the mouth and cheek muscles. 
 Mandibular Brs. 
 Cervical Brs. 
 
 8th Nerve, Auditory, Portio Mollis (n. acusticus) (Plate 10), the special 
 nerve of the sense of hearing, is soft in texture and destitute of neurilemma. 
 -arises from the groove between the pons and medulla, between the resti- 
 form body and the 7th nerve (22, Fig. 76); deeply from thejSflQr of the ^th 
 ventricle by 2 roots, one from the trigonum acustici, the other from the ac- 
 
THE CRANIAL NERVES 221 
 
 cessory nucleus and the tuberculum acusticum. Goes by the internal 
 auditory meatus; to the internal ear. It is the only cranial nerve which 
 does not leave the cranium. Its branches are two, the 
 
 Vestibular, to the vestibule. Qochlear, to the cochlea (see page 309). 
 
 2J* j 9th Nerve, Glosso-pharyngeal (n. glosso-pharyngeus) (Plate 9) ^sensory 
 
 * nerveTand nerve of taste, arises by 3 or 4 filaments from the medulla 
 
 oblongata in the groove between the olivary and restiform bodies (24, Fig. 
 
 76); deeply from a nucleus in the floor of the 4th ventricle and the tractus 
 
 or fasciculus solitarius in the lower part of the medulla; exit by the jugular 
 
 .foramen; to the mucous membrane of the fauces and base of the tongue, 
 
 and the mucous glands of the mouth and tonsil. It communicates with the 
 
 facial, pneumogastric (vagus) and sympathetic nerves. Its branches of 
 
 distribution are the 
 
 Tympanic or Jacobson's Nerve, described under Ear (see page 302). 
 
 Carotid Branches, along the internal carotid artery. 
 
 Pharyngeal, to the pharyngeal plexus. 
 
 Muscular, to the stylo-pharyngeus muscle. 
 
 Tonsillar Branches, forming the tonsillar plexus, thence to the soft 
 palate and fauces. 
 
 Lingjiql 2, one to the base, the other to the posterior half of the tongue, 
 being distributed to the mucous membrane, the papillae and the fol- 
 licular glands. 
 
 loth Nerve, Pneumogastric (n. vagus) (Plate 9), the auriculo-laryngo- 
 pharyngo-cesophago-tracheo-pulmono-cardio-gastro-hepatic nerve (Pan- 
 coast), is composed of both motor and^ensory fibres. It arises by 8 or 10 
 filaments from the medulla oblongata (25, Fig. 76) , between the olivary and 
 restiform bodies; deeply from the nucleus vagi in the floor of the 4th ven- 
 tricle, the tractus or fasciculus solitarius and the nucleus ambiguus in the 
 medulla; exit by the jugular foramen; and is distributed to the parts and 
 organs named in the afjove euphonious appellation; supplying sensory and 
 motor fibres to the organs of voice and respiration, and motor fibres alone 
 to the pharynx, cesophagus, stomach and heart. It has a ganglion on its 
 root and another on its trunk, thereby communicating with the 7th, gth, 
 nth and i2th cranial nerves, the ist and 2nd cervical nerves and the sym- 
 pathetic. Its branches of distribution are the 
 
 Meningeal (ramus meningeus), a recurrent filament to the dura mater. 
 
 Auricular (ramus auricularis) or Arnold's Nerve, to the external ear. 
 
 Pharyngeal (ramus pharyngeus), to the pharyngeal plexus. 
 
 Superior Laryngeal (n. laryngeus superior), a nerve of sensation to the 
 larynx, dividing into the External (ramus externus) and Internal 
 (ramus internus) Laryngeal. 
 
222 HUMAN ANATOMY 
 
 Recurrent Laryngeal (n. laryngeus inferior), the motor nerve of the 
 larynx; gives off cesophageal, tracheal and pharyngeal branches. 
 
 Cervical Cardiac Branches (rami cardiaci superiores), to the cardiac 
 plexuses. 
 
 Thoracic Cardiac Branches (rami cardiaci inferiores), 10 the deep car- 
 diac plexus. 
 
 Anterior Pulmonary Branches, to that plexus. 
 
 Posterior Pulmonary Branches, to that plexus. 
 
 (Esophageal Branches (rami cesophagei), to the cesophageal plexus. 
 
 Gastric (rami gastric), on the left side to the anterior surface of the 
 stomach, on the right side to the posterior surface; some filaments 
 going to the hepatic plexus. 
 
 i ith Nerve, Spinal Accessory (n. accessorious) (Plate 9), a motor nerve; 
 consists of the two parts, the accessory (ramus internus) to the vagus and 
 the spinal portion (ramus externus). The Accessory or Bulbar portion 
 (ramus internus) arises by 4 or 5 filaments from the medulla below the 
 vagus (26, Fig. 76); deeply from the nucleus ambiguus and the column 
 of cells underneath the ala cineria in the floor of the 4th ventricle; exit 
 by the jugular foramen; to the pharyngeal and superior laryngeal branches 
 of the vagus and through the former probably supplying the muscles of 
 the soft palate. The Spinal portion (ramus externus) arises by several 
 filaments from the lateral tract of the cord behind the anterior roots of the 
 upper five cervical spinal nerves; deeply from the dorso-lateral gray tract 
 of the cord from the olive down to the level of the 5th cervical nerve; exit 
 by the jugular foramen, having first entered the skull by the foramen mag- 
 num; to the sterno-mastoid and trapezius muscles, forming plexuses with 
 the 2d, 3d and 4th cervical nerves. 
 
 1 2th Nerve, Hypoglossal (n. hypoglossus), Nonus or Ninth of Willis 
 (Plate 10), the motor nerve of the tongue, arises by 10 to 15 filaments 
 from the medulla oblongata in the groove between the pyramid and the 
 olivary body (2 7, Fig. 76); deeply from the trigonum hypoglossi in the floor 
 of the 4th ventricle; exit by the anterior condylar foramen (canalis hypo- 
 glossi) in two bundles; to certain muscles of the tongue and other muscles; 
 communicating with the vagus, sympathetic, ist and 2d cervical and the 
 lingual. Its branches of distribution are the 
 
 Meningeal Branches, to the dura mater. 
 
 Descendens Hypoglossi (ramus descendens), to the sterno-hyoid, 
 sterno-thyroid and omohyoid muscles; joins the communicans hypo- 
 glossi branch of the cervical plexus. 
 
 Thyro-hyoid (ramus thyreohyoideus), to the thyro-hyoid muscle. 
 
GANGLIA OF CRANIAL NERVES 223 
 
 Muscular Branches, to the stylo-glossus, hyo-glossus, genio-hyoid and 
 genio-hyo-glossus muscles, and to the intrinsic muscles of the tongue 
 (rami linguales). 
 
 Nerves entering the Cranium before passing out of it, are the spinal 
 portion (ramus externus) of the spinal Accessory (n. accessorius), and the 
 Nasal branch (n. nasociliaris) of the Ophthalmic division of the 5th nerve. 
 The first enters by the foramen magnum, and leaves by the jugular fora- 
 men. The second enters from the orbit by the anterior ethmoidal fora- 
 men (canalis ethmoidale anterius), and leaves by the nasal slit at the side 
 of the crista galli. 
 
 GANGLIA OF THE CRANIAL NERVES 
 
 Ganglia are on and connected with several of the cranial nerves. Those 
 connected with the 5th nerve have each motor, sensory and sympathetic 
 roots. The various ganglia are named and connected as follows: 
 
 With the $d Nerve, the ophthalmic, lenticular, or ciliary ganglion (gan- 
 glion ciliare). 
 
 On the Fifth Nerve, the Gasserian or semilunar ganglion. 
 
 With the 5/A Nerve, the ophthalmic (ganglion ciliare), the spheno- 
 palatine (Meckel's), the otic, and the sub-mandibular or sub-maxil- 
 lary ganglia. 
 
 On the ith Nerve, the geniculate ganglion (ganglion geniculi) or intu- 
 mescentia ganglioformis. 
 
 With the ith Nerve, the spheno-palatine (Meckel's) ganglion, and the 
 otic ganglion. 
 
 With the Cochlear portion (radix cochlearis] of the 8th Nerve, the spiral 
 ganglion. 
 
 With the Vestibular portion (radix vestibularis] of the &th Nerve, the 
 vestibular ganglion (Scarpa's). 
 
 On the Qth Nerve, the jugular (ganglion superius) and petrous (ganglion 
 inferius) ganglia. 
 
 On the loth Nerve, the jugular or ganglion of the root (ganglion 
 jugulare), and the inferior or ganglion of the trunk (ganglion nodo- 
 sum). 
 
 With the nth Nerve, the jugular ganglion (ganglion jugulare) of the 
 loth nerve is connected with the accessory portion (ramus internus) 
 of the nth. 
 
 Gasserian or Semilunar Ganglion (Plate 7), on the sensory root of the 
 5th nerve, is situated near the apex of the petrous portion of the temporal 
 bone. It communicates with the carotid plexus of the sympathetic by 
 filaments on its inner side. Its branches are the 3 divisions of the sth 
 
224 HUMAN ANATOMY 
 
 nerve, the ophthalmic, maxillary, and mandibular, the latter trunk being 
 joined by the motor root (masticator nerve) of the nerve outside the cra- 
 nium. The ganglion also gives off minute branches to the tentorium 
 cerebelli and the dura mater in the middle cranial fossa. 
 
 Ophthalmic, Ciliary, or Lenticular Ganglion (ganglion ciliare) (Plate 
 6), is about the size of a pin's .head, and is situated at the back of the 
 orbit. Its roots are 3 in number, a sensory (radix longa ganglii ciliaris), 
 from the nasal branch (n. nasociliaris) of the ophthalmic; a motor root 
 (radix brevis ganglii ciliaris), from the 3d nerve; and a sympathetic root 
 (radix sympathetica ganglii ciliaris), from the cavernous plexus. Its 
 branches are the short ciliary nerves (nn. ciliares breves), to the ciliary 
 
 muscle, the iris and the cornea. 
 ^3 
 Spheno-palatine or Meckel's Ganglion (Plate 7), the largest of the 
 
 cranial ganglia, is situated in the spheno-palatine or pterygo-maxillary 
 fossa, close to the spheno-palatine foramen. Its roots are a sensory, 
 from the maxillary nerve; a motor, from the facial, through the large 
 superficial petrosal (n. petrosus superficialis major); and a sympathetic 
 root, from the carotid plexus, through the large deep petrosal (n. petrosus 
 profundus); the two last-named joining to form the Vidian nerve (n. 
 canalis pterygoidei) before entering the ganglion. Its branches are the 
 Ascending Branches (rami orbitales), to the orbit. 
 Anterior or Large Palatine (n. palatinus anterior), to the gums and 
 
 hard palate. 
 Middle or External Palatine (n. palatinus medius), to the uvula, tonsil 
 
 and soft palate. 
 Posterior or Small Palatine (n. palatinus posterior), to the levator 
 
 palati and azygos uvulae muscles, the soft palate, tonsil and uvula. 
 Superior Nasal Branches (rami nasales posteriores superiores), to the 
 mucous membrane of the superior and middle turbinal processes and 
 that lining the posterior ethmoidal cells. 
 Naso-palatine (n. nasopalatinus), to the mucous membrane behind 
 
 the incisor teeth, and that of the septum of the nose. 
 Pharyngeal or Ptery go- palatine, to the mucous membrane of the upper 
 
 part of the pharynx. 
 
 Posterior Nasal Branches (rami nasales posteriores inferiores), to 
 the mucous membrane at the back of the roof of the mouth, and 
 that of the septum and superior meatus of the nose. 
 
 Otic Ganglion (ganglion oticum), Arnold's (Plate 7), is situated on the 
 inner surface of the mandibular nerve, immediately below the fora- 
 men ovale. Its roots are a sensory, from probably the glosso-pharyngeal; 
 
GANGLIA OF CRANIAL NERVES 225 
 
 a motor, from probably the facial; both through the small superficial 
 petrosal (n; petrosus superficial minor) continued from the tympanic 
 plexus; and a sympathetic root from the middle meningeal plexus. It 
 communicates also with the internal pterygoid branch of the mandibular, 
 and with the auriculo-temporal. Its branches are a filament (n. tensoris 
 tympani) to the tensor tympani muscle, one (n. tensoris veli palatini) to 
 the tensor palati, and one to the chorda tympani nerve. 
 
 Sub -mandibular or Sub-maxillary Ganglion (Plate 7) is situated above 
 the sub-maxillary gland. Its roots are a sensory (rami communicantes 
 cum n. linguali), from the lingual branch of the mandibular; a motor, 
 from the facial by the chorda tympani; and a sympathetic root from the 
 facial plexus. Its branches (rami sub- 
 
 maxillares) are 5 or 6 in number, dis- IG> 79> 
 
 tributed to the mucous membrane of 
 the mouth, Wharton's duct (ductus 
 sub-maxillaris), and thesub-mandibular 
 or sub-maxillary gland. 
 
 Geniculate Ganglion (ganglion gen- 
 iculi) (2) or Intumescentia Ganglio- 
 formis (Plate 8), is a reddish, gangli- 
 form swelling on the yth or facial 
 nerve, situated in the aquasductus 
 Fallopii (canalis facialis), above the 
 tympanum and near the Gasserian 
 ganglion (ganglion semilunare). It 
 communicates with the spheno-pala- 
 tine ganglion, the otic ganglion and 
 
 the meningeal plexus of the sympathetic, by the 3 superficial petrosal 
 nerves, which are seen on removing the Gasserian ganglion (ganglion semi- 
 lunare) (7), as follows: 
 
 Large Superficial Petrosal (3), passes through the hiatus Fallopii 
 (hiatus canalis facialis), thence across the foramen lacerum medium 
 to the Vidian canal (canalis pterygoidei) where it joins the large deep 
 petrosal from the carotid plexus, to form the Vidian nerve (n. canalis 
 pterygoidei), as which it goes to Meckel's ganglion (ganglion spheno- 
 palatinum) (page 224), forming its motor root. 
 
 Small Superficial Petrosal (4), immediately external to the preceding, 
 going from the geniculate ganglion of the yth to the otic ganglion, 
 lying directly over the tensor tympani muscle. 
 
 External Superficial Petrosal (5), going from the 7th nerve to the 
 sympathetic plexus on the middle meningeal artery (6). 
 IS 
 
226 HUMAN ANATOMY 
 
 The Vidian Nerve (n. canalis pterygoidei) (Plate 8), is a short nerve 
 of communication, between the facial and sympathetic on the one hand, 
 and the spheno-palatine ganglion on the other, supplying that ganglion 
 with its motor and vaso-motor roots. It is formed by the junction of 
 the 
 
 Large Superficial Petrosal, br. of the facial (p. 220), with the 
 
 Large Deep Petrosal, br. of the carotid plexus (p. 237), which tunnels the 
 cartilage filling in the foramen lacerum medium (p. 41). It then en- 
 ters the Vidian canal (canalis pterygoidei) (p. 25) in the pterygoid 
 process of the sphenoid bone, passing through which it finally joins 
 the posterior part of the spheno-palatine ganglion (p. 224). 
 
 Ganglia of the pth Nerve (Plate 9). The Jugular Ganglion (ganglion 
 superius) is regarded as a segmentation from the petrous ganglion (gan- 
 glion inferius) below. The Petrous Ganglion (ganglion inferius) is situated 
 in a depression on the lower border of the petrous portion of the temporal 
 bone. From it arise the filaments which connect the gth nerve with the 
 loth and the sympathetic; and it communicates also with the yth nerve. 
 Its branches of distribution are the tympanic, carotid, pharyngeal, muscu- 
 lar, torisillar, and lingual branches of the gth nerve (see page 221). 
 
 Ganglia of the loth Nerve (Plate 9). The Ganglion of the Root (gan- 
 glion jugulare) is connected by filaments with the accessory portion 
 (ramus internus) of the nth nerve, with the petrous (inferior) ganglion 
 of the 9th, with the yth, and with the sympathetic. The Ganglion of the 
 Trunk (ganglion nodosum) involves all the fibres of the nerve, as also the 
 accessory portion (ramus internus) of the nth, which passes through it. 
 It is connected with the 1 2th nerve, the superior cervical ganglion of the 
 sympathetic, and the loop between the ist and 2d cervical nerves. 
 
 THE SPINAL NERVES (NERVI SPINALES) 
 
 The Spinal Nerves number 31 pairs, of which the cervical number 8, 
 the thoracic 12, the lumbar 5, the sacral 5, and the coccygeal i. All the 
 cervical nerves escape above the corresponding vertebrae except the 8th 
 which emerges between the jth cervical and ist thoracic vertebrae, each 
 of the others below the corresponding vertebrae, through the intervertebral 
 foramina. Each nerve arises by 2 roots, an anterior motor root (effer- 
 ent), and a posterior sensory one (afferent), the latter having a ganglion 
 on it, the spinal ganglion, situated in the intervertebral foramen. The 
 roots unite, and the spinal nerve thus formed divides into 2 divisions (rami), 
 each having motor and sensory fibres. Just before this division takes 
 
THE SPINAL NERVES 227 
 
 place, each nerve gives off a minute gray ramus communicans, which 
 after being joined by a branch of the sympathetic, re-enters the spinal 
 canal and is distributed to the spinal cord (medulla spinalis) and its 
 meninges, these are called recurrent meningeal nerves. The posterior 
 divisions (rami) are small and generally unimportant; they supply the 
 muscles and integument of the back. The anterior divisions (rami) 
 supply the neck, front, and sides of the trunk, and the extremities; unit- 
 ing in various regions to form plexuses, from which important nerve- 
 trunks originate. Each anterior division (ramus), from 2d thoracic to 2d 
 lumbar inclusive, is connected by a slender filament with the sympathetic. 
 These are called splanchnic branches or "white rami communicantes ; there 
 is a second set of them given by the 2d and 3d or by the 3d and 4th sacral 
 nerves. 
 
 THE CERVICAL NERVES 
 
 The Cervical Nerves (Plate n), are 8 in number. The anterior divi- 
 sions of the 4 upper form the cervical plexus; the anterior divisions of the 
 lower 4, together with the ist thoracic, form the brachial plexus. The 
 posterior division (ramus) of the ist cervical, the suboccipital nerve, 
 differs from the others in not dividing into internal and external branches. 
 It gives off a communicating branch, to the second cervical, and 5 muscular 
 branches. The posterior division (ramus) of the 2d cervical is much 
 larger than the anterior, it is called the Great Occipital (n. occipitalis 
 magnus), a cutaneous nerve. 
 
 The Cervical Plexus (plexus cervicalis) (Plate n), is formed by the 
 anterior divisions of the upper 4 cervical nerves. It is situated opposite 
 the upper 4 cervical vertebrae, resting on the levator anguli scapulae (m. 
 levator scapulae) and scalenus medius muscles and covered in by the sterno- 
 mastoid. Its branches number 10, of which the first 4 are superficial and 
 the last 6 are deep, as follows: 
 
 Occipitalis Minor (n. occipitalis minimus), ascending to the back of 
 the side of the head. 
 
 ( Facial, to the skin over the parotid gland. 
 
 Auricularis Magnus \ Auricular, to the skin of the pinna, concha, etc. 
 I Mastoid, to the integument behind the ear. 
 
 Superficial Cervical (n. cutaneous colli), by 2 branches to the skin of 
 the neck. 
 
228 HUMAN ANATOMY 
 
 Supraclavicular 
 
 Suprasternal (nn. supraclaviculares anteriores), to 
 
 the skin of that region. 
 Supraclavicular (nn. supraclaviculares medii), to 
 
 the skin over the pectoral and deltoid. 
 Supra-acromial (nn. supraclaviculares posteriores), 
 
 to the skin of the shoulder. 
 
 Communicating, brs. to the loth (vagus), i2th (hypoglossal) and 
 sympathetic nerves. 
 
 Muscular, to the anterior recti and rectus lateralis muscles. 
 
 Communicantes Hypoglossi 2, join the descendens hypoglossi nerve. 
 
 Phrenic, is described below. 
 
 Deep Communicating, to the spinal accessory nerve. 
 
 Deep Muscular, to the sterno-mastoid, trapezius, levator anguli 
 - ^scapulas (m. levator scapulae) and scalenus medius muscles. 
 
 The Phrenic Nerve (nervus phrenicus), or Internal Respiratory of Bell, 
 arises by 3 heads from the 3d, 4th, and 5th cervical, descends across the 
 front of the scalenus anticus (m. scalenus anterior), crossing the sub- 
 clavian and internal mammary arteries in the middle mediastinum, and is 
 distributed to the inferior surface of the diaphragm. It sends filaments 
 to the pericardium and pleura, and communicates with the solar and 
 phrenic plexuses of the sympathetic in the abdomen. On the right side 
 of the body it is situated more deeply, and is shorter and more vertical in 
 direction than on the left side. In the thorax each phrenic nerve is 
 accompanied by the comes nervi phrenici artery, a branch of the internal 
 mammary. 
 
 The Brachial Plexus (plexus brachialis) (Plate 12), is formed by the 
 union of the anterior division of the four lower cervical nerves and the first 
 thoracic. The 5th, 6th and 7th cervical unite into one trunk externally 
 to the scalenus medius, as also do the 8th cervical and ist thoracic behind 
 the same muscle. Below the line of the clavicle both these trunks bifur- 
 cate; the two adjacent branches unite behind the axillary artery making 
 the Posterior Cord, and the remaining 2 form the Outer (lateral) and Inner 
 (medial) Cords, as referred to the artery. Each of these cords bifurcates, 
 but the 2 adjacent branches of the outer and inner cords unite over the 
 artery, to form the Median Nerve, leaving 4 other branches, the Ulnar, 
 derived from the inner cord, iheMusculo-cutaneous (n. musculocutaneus), 
 from the outer cord, and the Musculo-spiral (n. radialis) and Circumflex 
 (n. axillaris) from the posterior cord. (See Plate 12.) 
 
 THE BRANCHES of the brachial plexus are as follows: 
 Above the clavicle are given off 4, the 
 
THE SPINAL NERVES 2 29 
 
 /J Communicating, completing the phrenic nerve. 
 
 * / Musctttar, to The longus colli, scaleni, rhomboidei, and subclavius 
 / muscles. The branch actuating the rhombcidei and levator anguli 
 scapulae (n. levator scapulae) is sometimes called the posterior 
 . scapular (n. dorsalis scapulae). 
 
 / Posterior, or Long Thoracic (n. thoracalis longus), external respiratory 
 ' nerve of Bell, -to the serratus magnus, arising from the 5th, 6th and 
 
 . 7th cervical. 
 / Suprascapular, from the ist trunk of the plexus, to the supra- and in- 
 
 fra-spinatus muscles and the shoulder-joint. 
 Below the clavicle are 12, namely, the 
 /) Anterior Thoracic 2, external (lateral) and internal (medial) from the 
 
 outer (lateral) and inner (medial) cords, to the pectoral muscles. 
 Subsca pular 3, from the posterior cord, to the subscapularis, teres 
 major and latissimus dorsi muscles. The long sw&scapular is also 
 called nervus thoracodorsalis. 
 2, j Circumflex (n. axillaris), from the posterior cord, to the muscles and 
 
 integument of the shoulder, and the shoulder-joint. 
 JMusculo-cutaneous (n. musculocutaneus), from the outer cord, to 
 the forearm externally, piercing the coraco-brachialis muscle. Its 
 cutaneous branch is also called nervus cutaneus antibrachii lateralis. 
 ' Internal Cutaneous (n. cutaneus antibrachii medialis), from the inner 
 
 cord, to the arm and forearm. 
 
 Lesser Internal Cutaneous (n. cutaneus brachii medialis) nerve of Wris- 
 berg, from the inner cord, to the back of the arm. Is sometimes 
 . wanting, sometimes connected with the intercosto-humeral. 
 V : Median (n. medianus), from outer (lateral) and inner (medial) cords, 
 passes between the two heads of the pronator radii teres (m. pronator 
 teres), supplying the pronators, flexors, first 2 lumbricales, and the 
 integument of the thumb, 2^ fingers, and the radial side of the palm. 
 Its branches are all in the forearm, except its terminals in the palm of 
 the hand, and are named the 
 Muscular. 
 
 Anterior Interosseous (n. interosseus antibrachii volaris). 
 Palmar Cutaneous (n. ramus cutaneus palmaris n. mediani). 
 . f Br. to thumb muscles. 
 \ Digital, (nn. digitales volares communes) to thumb and index. 
 
 J Digital (nn. digitales volares proprii) to thumb, and 2^ 
 lntcrn.3,1 \ /. 
 
 ( fingers. 
 
 Ulnar, from the inner (medial) cord, passes between the two heads of 
 
230 HUMAN ANATOMY 
 
 the flexor carpi ulnaris at the inner condyle of the humerus, supplying 
 the elbow- and wrist-joints, several muscles, and the palmar and dorsal 
 integument of the little finger and half of the ring finger. Branches 
 are the 
 
 Articular (elbow). Dorsal Cutaneous. Superficial Palmar. 
 Muscular. Articular (wrist). Deep Palmar. 
 
 Cutaneous. 
 
 . I Musculo-spird (n. radialis), from the posterior cord, accompanies the 
 
 / superior profunda artery and vein in the spiral groove of the humerus, 
 
 and in front of the outer (lateral) condyle it divides into the radial 
 
 (ramus superficialis n. radialis) and posterior interosseous (ramus 
 
 prof undus n. radialis) nerves. Its branches are 
 
 Muscular (rami musculares n. radialis) divided into internal (medial) 
 posterior, and external (lateral). 
 
 Cutaneous (rami collaterals n. radialis) one internal (n. cutaneus 
 brachii posterior) and two external (n. cutaneous brachii posterior, 
 ramus proximalis et ramus distalis). 
 
 Radial (ramus superficialis n. radialis) divides into an external and an 
 internal branch, the latter giving off 4 digital, to the ulnar side of the 
 thumb and the adjacent sides of 2^ fingers. Communicating branch 
 to ulnar (ramus anastomoticus ulnaris). 
 
 Posterior Interosseous (ramus prof undus n. radialis), supplies all the 
 muscles of the radial side and back of the arm, except 3, also the liga- 
 ments and articulations of the carpus. 
 
 TABLE OF THE CORDS OF THE BRACHIAL PLEXUS 
 
 Outer or Lateral Cord (superior) 
 
 Musculo-cutaneous (n. musculotaneus) . derivation 5, 6, C. 
 
 External (lateral) Anterior Thoracic derivation 5, 6, 7, C. 
 
 Outer (lateral) head of Median 'derivation 6, 7, C. 
 
 Inner or Medial Cord (inferior) 
 
 Inner (medial) head of median derivation 8, C. i, T. 
 
 Internal (medial) Anterior Thoracic.. . .derivation 8, C. i, T. 
 Internal Cutaneous (n. cutaneus anti- 
 
 brachii medialis) derivation 8, C. i, T. 
 
 Lesser Internal Cutaneous (n. cutaneus 
 
 brachii medialis) derivation i, T. 
 
 Ulnar derivation 8, C. i, T. 
 
THE SPINAL NERVES 231 
 
 Posterior Cord 
 
 Upper Subscapular derivation 5, 6, C. 
 
 Long Subscapular (n. thoraco-dorsalis). derivation 5, 6, 7, C. 
 
 Lower Subscapular derivation 5, 6, C. 
 
 Circumflex (n. axillaris) derivation 5, 6, C. 
 
 Musculo-Spiral (n. radialis) derivation 5,6, 7,8.C. (i, 7\). 
 
 THE THORACIC NERVES (NERVI THORACALES) 
 
 The Thoracic Nerves (Plate 12) are 12 in number on each side. Their 
 posterior divisions pass backward beneath the transverse processes, and 
 divide into internal and external branches, supplying the muscles and in- 
 tegument of the back. Their anterior divisions, the intercostal nerves, are 
 distributed to the walls of the thorax and abdomen, separately from each 
 other, without plexiform arrangement. The upper 6, except the ist and 
 the intercosto-humeral (intercosto-brachial) branch of the 2d, are lim- 
 ited in their distribution to the parietes of the chest. The lower 6 supply 
 the walls of the chest and abdomen, the last one sending a cutaneous fila- 
 ment to the buttock. The Lateral Cutaneous nerves are derived from the 
 intercostals, midway between the vertebrae and the sternum; they pierce 
 the external intercostal and serratus magnus (m. serratus anterior) mus- 
 cles, and divide into anterior and posterior branches. Peculiar among the 
 thoracic nerves and their branches are the 
 First Thoracic, divides into 2 branches, one entering into the brachial 
 
 plexus, the other forming the ist intercostal nerve. 
 
 Intercosto-humeral (n. Intercostobrachialis), is the lateral cutaneous 
 branch of the 2d intercostal (anterior division of the 2d thoracic); it 
 pierces the external intercostal muscle and crosses the axilla, joining 
 with a filament from the lesser internal cutaneous (n. cutaneus 
 brachii medialis) (nerve of Wrisberg), supplying the skin of the upper 
 half of the inside and back of the arm, and communicating with the 
 internal cutaneous (n. cutaneus brachii posterior) branch of the mus- 
 culo-spiral nerve (n. radialis). 
 
 Last Thoracic, is larger than the other thoracic nerves. Its anterior 
 division runs along the lower border of the last rib, and communicates 
 with the first lumbar nerve by the thoraco-lumbar branch, also with 
 the ilio-hypogastric branch of the lumbar plexus. One of its 
 branches, the 
 
 Lateral Cutaneous- of the i2th Thoracic, is also of large size, and is dis- 
 tributed to the integument over the front part of the gluteal region, 
 some of its filaments extending as low as the trochanter major of the 
 femur. 
 
232 HUMAN ANATOMY 
 
 THE LUMBAR NERVES 
 
 The Lumbar Nerves are 5 in number on each side. Their roots are large 
 and descend vertically in the spinal canal to reach their respective inter- 
 vertebral foramina of exit. Their posterior divisions pass backward 
 between the transverse processes, and divide into internal (medial) 
 branches, supplying the deep muscles of the back; and external (lateral) 
 branches are mostly cutaneous. Their anterior divisions pass outwardly 
 behind the psoas magnus muscle or between its fasciculi. The anterior 
 divisions of the upper 4 nerves are connected by anastomotic loops, form- 
 ing the lumbar plexus; that of the 5th with a branch of the 4th forms the 
 lumbo-sacral cord (truncus lumbosacralis), which joins with the anterior 
 divisions of the upper 3 sacral nerves and part of the 4th to form the sacral 
 plexus. (See Plate 14.) 
 
 The Lumbar Plexus (plexus lumbalis) (Plate 14), is formed by loops 
 from the 1 2th thoracic and the upper 4 lumbar nerves. It is situated in the 
 substance of the psoas magnus muscle in front of the transverse processes 
 of the lumbar vertebrae. Its branches are given off by the connecting 
 loops, and are as follows: 
 
 Ilio-hypo gastric, from the ist lumbar nerve, to the integument of the 
 gluteal and hypogastric regions. 
 
 Ilio-inguinal, from the ist lumbar nerve, gives off muscular branches 
 to the internal oblique as it pierces it. It then accompanies the 
 spermatic cord, or round ligament, divides into anterior scrotal or 
 anterior labial to the integument of the upper and inner thigh and to 
 the scrotum or labium majus. 
 
 Genito-crural (genito-f emoral) , from the ist and 26. lumbar nerves, 
 gives off genital branch (n. spermaticus externus), to the cremaster 
 muscle or round ligament, and a femoral branch (n. lumbo-inguinalis) 
 to the integument over the anterior superior part of the thigh. 
 
 External Cutaneous (n. cutaneus femoris lateralis), from the 2nd and 
 3rd lumbar nerves, to the integument of the anterior, outer and pos- 
 terior parts of the thigh. 
 
 Obturator (n. obturatorius), from the 2nd, 3rd, and 4th lumbar nerves, 
 through the obturator foramen, to the obturator externus and adduc- 
 tor muscles of the thigh, the hip- and knee-joints, and occasionally the 
 integument of the thigh and leg. 
 
 Accessory Obturator (n. obturatorius accessorius) (often absent), from 
 the 3rd and 4th lumbar nerves, to the pectineus muscle and the 
 hip-joint. 
 
THE SPINAL NERVES 233 
 
 Anterior Crural (n. femoralis), from the 2nd, 3rd, and 4th lumbar 
 nerves, to the iliacus and pectineus muscles, all the muscles on the 
 front of the thigh except the tensor fasciae femoris, the hip- and knee- 
 joints, and the integument on the front and inner side of the thigh. It 
 descends through the psoas magnus muscle, passing beneath Pou- 
 part's inguinal ligament to the thigh, where it divides into an interior 
 and a posterior division. Its branches are 
 Muscular, within the abdomen, to the iliacus muscle. 
 Arterial, within the abdomen, to the femoral artery. 
 Middle Cutaneous, to the skin on the front of the thigh. 
 Internal Cutaneous, to the skin on the knee and leg. 
 Muscular, to the pectineus and sartorius muscles. 
 Long Saphenous (n. saphenus), to the skin over the patella and that on 
 
 the front and inner side of the leg. 
 Muscular, to the quadriceps extensor muscle. 
 Articular Branches, to the hip- and knee-joints. 
 
 THE SACRAL AND COCCYGEAL NERVES 
 
 The Sacral Nerves number 5, the Coccygeal i, on each side. Their roots 
 are long and descend vertically in the spinal canal as the cauda equina or 
 horse's tail, to reach their respective foramina of exit. Their posterior divi- 
 sions are small; they supply the multifidus spinae muscles and the skin of 
 the gluteal region; those of the lower 2 sacral and the coccygeal supplying 
 the extensor coccygis and the skin over the coccyx. Their anterior divisions 
 communicate with the sacral ganglia of the sympathetic; those of the 3 
 upper sacral, with the lumbo-sacral cord (truncus lumbo-sacralis) and a 
 branch from the 4th sacral, unite to form the sacral plexus. The anterior 
 division of the 4th sacral divides into visceral and muscular branches, the 
 former supplying the pelvic viscera, the latter the levator ani, sphincter 
 ani, and coccygeus muscles. The anterior division of the 5th sacral and 
 the coccygeal supply the coccygeus muscle and the skin over the coccyx. 
 
 The Sacral Plexus (Plexus Sacralis) (Plate 14), is formed by the union 
 of the anterior divisions of the upper 3 and part of the 4th sacral nerves (c), 
 with the lumbo-sacral cord (truncus lumbo-sacralis) (a) derived from the 
 4th and 5th lumbar nerves. The plexus lies upon the pyriformis muscle, is 
 covered by the pelvic fascia, communicates with the sympathetic, and 
 gives off 2 great nerve-trunks or cords, the upper cord being prolonged as the 
 great sciatic nerve, the lower cord becoming the pudic nerve, both passing 
 out of the pelvis by the great sacro-sciatic foramen. The branches of the 
 sacral plexus are as follows: 
 
234 
 
 HUMAN ANA10MY 
 
 FIG. 80. 
 
 Muscular Branches, to the pyriformis, obturator interims, the 2 gemelli 
 
 and the quadratus femoris. 
 
 Superior Gluleal (n. glutaeus superior) (b), from the lumbo-sacral cord, 
 to the gluteus medius and minimus muscles 
 and the tensor fasciae femoris. 
 
 Inferior Gluleal (n. glutaeus inferior), from the 
 lumbo-sacral cord and the ist and 26. sacral 
 nerves, to the gluteus (glutaeus) maximus muscle. 
 Small Sciatic (n. cutaneus femoris posterior) (/), 
 from the 2d and 3d sacral nerves, to the integu- 
 ment of the perineum and back part of the thigh 
 and leg, by gluteal, perineal and femoral cuta- 
 neous branches. 
 
 Perforating Cutaneous (n. clunium inferior medialis), 
 sometimes classed as a branch of the "pudendal 
 plexus," from the 2d and 3d sacral nerves, 
 perforating the great sacro-sciatic (sacro-tu- 
 berous) ligament, to the skin over the gluteus 
 maximus muscle. 
 
 Pudic (n. pudendus), sometimes classed as a branch 
 of the "pudendal plexus" (e), from the 3d and 
 4th sacral nerves, escapes by the great sacro- 
 sciatic foramen, crosses the spine of theischium, 
 and re-enters the pelvis through the lesser sacro- 
 sciatic foramen, to supply the perineum, anus 
 and genitalia. Its branches are the 
 
 Inf. Hemorrhoidal (n. haemorrhoidalis inferior). 
 Perineal (n. perinei), dividing into 2 super- 
 ficial perineal cutaneous branches and mus- 
 cular branches to all of the perineal muscles. 
 Dorsal Nerve of the Penis (n. dorsalis penis vel 
 
 clitoridis). 
 
 Great Sciatic (n. ischiadicus) (g), the largest ner- 
 vous cord in the body, and the continuation of 
 the upper cord of the sacral plexus, arises from 
 the lumbo-sacral cord and the upper 4 sacral 
 nerves, and escapes by the great sacro-sciatic 
 foramen to the back of the thigh, giving off 
 
 Articular Branches (rami articulares), to the hip-joint. 
 
 Muscular Branches (rami musculares), to the flexor muscles of the 
 
THE SPINAL NERVES 235 
 
 leg, viz. the biceps, semitendinosus and semimembranosus, also 
 to the adductor magnus. 
 
 External (n. peronaeus communis) (K) and Internal (n. tibialis) (i) 
 Popliteal, the terminal branches, generally arising at the lower 
 third of the thigh. 
 
 The Internal Popliteal Nerve (n. tibialis) (i), the larger of the two ter- 
 minal branches of the great sciatic, descends along the back of the lower 
 thigh and the middle of the popliteal space, to the lower part of the 
 popliteus muscle, where it becomes the Posterior Tibial Nerve (&). Its 
 branches are the 
 
 Articular (rami articulares) 3, supplying the knee-joint. 
 
 Muscular (rami musculares) (j), 4 or 5, to the gastrocnemius, plantaris, 
 
 soleus and popliteal muscles. 
 Communicant Tibialis (ramus anastomoticus tibialis), joins the com- 
 
 municans peronei from the external popliteal nerve to form the 
 External or Short Saphenous (n. cutaneus surae medialis) (/), descends 
 to the outer malleolus and is distributed to the skin of the outer side of 
 the foot and the little toe. 
 
 The Posterior Tibial Nerve (&), the continuation of the internal popliteal 
 descends along the back of the leg to behind the inner malleolus, where it 
 divides into the External (lateral) and Internal (medial) Plantar nerves (/). 
 Its branches are the 
 
 Muscular (rami musculares), to the soleus, tibialis posticus, flexor 
 
 longus digitorum and flexor longus hallucis. 
 Calcaneo- plantar or Internal Calcaneal (rami calcanei mediales), to the 
 
 skin of the heel and inner side of the sole of the foot. 
 Articular (ramus articularis ad articulationem talocrualem), to the 
 
 ankle-joint. 
 
 Internal Plantar (n. plantaris medialis), to the inner plantar muscles, 
 sole of the foot, and the plantar integument of the inner 3^ toes (nn. 
 digi tales plantares communes). 
 
 External Plantar (n. plantaris lateralis), to the external plantar mus- 
 cles, and the plantar integument of the outer ij^j toes (nn. digitales 
 plantares communes). 
 
 The External Popliteal or Peroneal Nerve (n. peronaeus communis) (h), 
 the smaller of the two terminal branches of the great sciatic (n. ischiadicus), 
 descends from the bifurcation of the latter nerve, obliquely along the outer 
 side of the popliteal space, winds around the neck of the fibula, and about 
 an inch below the head of that bone it divides into the Anterior Tibial 
 or Deep Peroneal (n. peronaeus profundus) (m) and Musculo-cutaneous or 
 
236 HUMAN ANATOMY 
 
 Superficial Peroneal (n. peronaeus superficialis) (n) nerves. Its branches 
 are 
 
 Articular (rami articulares), 3, to the front and outer side of the knee. 
 
 Cutaneous (n. cutaneus surae lateralis), 2 or 3, to the integument along 
 the back and outer side of the leg. One of these branches, the 
 
 Communicant Peronei (ramus anastomoticus peronaeus), joins with the 
 communicans tibialis (ramus anastomoticus tibialis) (see above) 
 to form the external saphenous nerve (n. cutaneus surae medialis). 
 
 Anterior Tibial or Deep Peroneal (n. peronaeus profundus) (m), sup- 
 plying the extensor muscles, the ankle-joint, and the integument of 
 the adjacent sides of the great and 26. toes. 
 
 Musculo-cutaneous or Superficial Peroneal (n. peronaeus superficialis) 
 (n), by 2 branches (0) (internal and external) to the peroneal 
 muscles, the integument of the ankles, and the dorsal integument 
 (n. cutaneous dorsalis medialis) and sides of all the toes, except the 
 outer side of the little toe and the adjoining sides of the great and 2d 
 toes, the former being supplied by the external saphenous (n. cuta- 
 neus surae medialis), and the latter by the internal (medial) branch of 
 the anterior tibial. 
 
 THE SYMPATHETIC SYSTEM 
 
 The Sympathetic Nervous System consists of a series of ganglia, 
 connected together by intervening cords, one series on each side of the 
 median line of the body, partly in front and partly on each side of the 
 vertebral column, beginning in the ganglion of Ribes on the anterior com- 
 municating artery and ending in the ganglion impar in front of the coccyx; 
 three great gangliated plexuses, situated in the thoracic, abdominal, and 
 pelvic cavities respectively; smaller ganglia, in relation with the abdominal 
 viscera; and numerous communicating and distributing nerve fibres. 
 (See Plate 16.) 
 
 Ganglia in the Cranium. Besides the ganglia of the cranial nerves 
 (described on page 223), all of which are connected with the sympathetic, 
 there are in the cranium or in its immediate vicinity certain ganglia belong- 
 ing to the sympathetic system, as follows: 
 
 Carotid Ganglion, on the internal carotid artery. 
 
 Ganglion of Bochdalek, above the canine tooth at the junction of a 
 branch from the spheno-palatine ganglion with the middle superior 
 alveolar and anterior superior alveolar nerves. 
 
 Ganglion of Valent ine, situated at the juncture of the middle superior 
 alveolar and the posterior superior alveolar nerves. 
 
THE SYMPATHETIC SYSTEM 237 
 
 The Carotid Plexus is situated on the outer side of the internal carotid 
 artery, as it lies by the side of the body of the sphenoid bone, and is formed 
 by filaments from the outer branch of the superior cervical ganglion. It 
 communicates with the Gasserian ganglion (ganglion semilunare) and the 
 6th nerve; also with the tympanic branch of the gth by two branches, the 
 small deep petrosal and the carotko-tympanic; and with the spheno-pala- 
 tine ganglion by the large deep petrosal, which joins the great superficial 
 petrosal to form the Vidian nerve (n. canalis pterygoidei) before entering 
 the ganglion (see page 226). 
 
 The Cavernous Plexus is situated in the upper portion of the cavernous 
 sinus, below the last bend of the internal carotid artery, and is formed 
 chiefly by the internal division of the ascending branch from the superior 
 cervical ganglion. It communicates with the 3rd, 4th, ophthalmic divi- 
 sion of the $th, and the 6th nerves, also with the ophthalmic ganglion. It 
 sends filaments to the wall of the internal carotid artery, which are pro- 
 longed into plexuses around the cerebral and ophthalmic arteries. The 
 filaments on the anterior communicating artery form the ganglion of Ribes, 
 which here connects the sympathetic of the two sides of the body. 
 
 tf THE GANGLIATED CORD (TRUNCUS SYMPATHETICUS) 
 " ' 
 
 The Cervical Ganglia are 3 in number on each side of the neck, the supe- 
 rior, middle and inferior cervical; of which the superior is the largest and is 
 probably formed by the coalescence of four ganglia corresponding to the 
 upper four cervical nerves. They are as follows: 
 Superior Cervical Ganglion, of fusiform shape, situated behind the 
 carotid sheath opposite the transverse processes of the 2d and 3d 
 cervical vertebrae. Its branches form the carotid, cavernous, and 
 pharyngeal plexuses; one of its internal branches unites with the 
 superior laryngeal nerve, and another is the superior cervical cardiac 
 nerve going to the cardiac plexuses. 
 
 Middle Cervical Ganglion, on the inferior thyroid artery, opposite the 
 6th cervical vertebra gives off the middle cardiac nerve to the deep 
 cardiac plexus, also many communicating branches. 
 Inferior Cervical Ganglion, on the superior intercostal artery, between 
 the neck of the ist rib and the transverse process of the 7th cervical 
 vertebra. It gives off several communicating branches and the 
 inferior cardiac nerve to the deep cardiac plexus. 
 
 The Thoracic Ganglia are 1 1 or 1 2 in number on each side of the spine, 
 resting against the heads of the ribs and covered by the pleura costalis, 
 
238 HUMAN ANATOMY 
 
 except the last two, which are placed on the side of the bodies of the nth 
 and 1 2th thoracic vertebrae. Occasionally two ganglia coalesce into one, 
 and the first is frequently blended with the last cervical ganglion. They 
 are connected together by cords prolonged from their substance. They 
 receive branches (white rami communicantes) from the thoracic nerves. 
 They give off central branches (gray rami communicantes) connecting with 
 the thoracic spinal nerves; and peripheral branches from the upper 5 or 6 
 ganglia to the thoracic aorta, etc., from the 3rd and 4th ganglia to the 
 posterior pulmonary plexus, and from the lower 6 or 7 ganglia to form by 
 their union the three splanchnic nerves, as follows: 
 Great Splanchnic, from branches of the 5th to the loth inclusive, con- 
 necting with the upper 5, passes through the posterior mediastinum, 
 perforates the crus of the diaphragm, to the semilunar (coeliac) 
 ganglion of the solar (cceliac) plexus. 
 
 Lesser Splanchnic, from the loth and nth, passes through the dia- 
 phragm with the great splanchnic, to the renal and solar (cceliac) 
 plexuses. 
 
 Least or Renal Splanchnic, from the last thoracic ganglion, also per- 
 forates the diaphragm, and ends in the renal plexus; it is not always 
 present. 
 
 The Lumbar Ganglia consist usually of 4 small ganglia on each side, 
 connected together by intervening cords, and situated in front of the ver- 
 tebral column. Their central branches (gray rami communicantes) com- 
 municate with the lumbar spinal nerves. Of their peripheral branches 
 some help to form the aortic plexus, others go to the hypogastric plexus, 
 and all give off numerous filaments to the bodies of the lumbar vertebrae 
 and the ligaments connecting them. The lumbar ganglia receive branches 
 (white rami communicantes) from the ist, 2d and sometimes 3d lumbar 
 nerves. 
 
 The Pelvic Ganglia are 4 or 5 small ganglia on each side, connected to- 
 gether by intervening cords, and situated in front of the sacrum. The 
 lower cords of each side converge below and unite on the front of the coccyx 
 in the coccygeal ganglion or ganglion coccygeum impar. Their central 
 branches (gray rami communicantes), 2 from each ganglion, communicate 
 with the sacral nerves. Of the peripheral branches, some pass to the pelvic 
 plexus, others go to a plexus on the middle sacral artery and all communi- 
 cate on the front of the sacrum with the corresponding branches of the 
 other side. The sacral portion of the sympathetic trunk receives one with 
 rami communicantes. 
 
THE SYMPATHETIC SYSTEM 239 
 
 THE GREAT PLEXUSES (Plate 16) 
 
 The Great Plexuses of the Sympathetic are large aggregations of nerves 
 and ganglia, situated in the tkpracic, abdominal, and pelvic cavities, and 
 named the Cardiac Plexus, the Coeliac or Solar Plexus, and the Hypo- 
 gastric Plexus. Their branches form secondary plexuses which supply the 
 viscera of the cavities, as described below. 
 
 The Cardiac Plexus is situated at the Jjase of the heart, and is divided 
 into a superficial portion and a deep portion, both of which are closely con- 
 nected with each other. They form by their branches the anterior and 
 posterior coronary plexuses and the anterior pulmonary plexus. 
 
 The Superficial Cardiac Plexus is formed by the left superior cardiac 
 nerve, the left inferior cervical cardiac branches of the pneumogastric, and 
 filaments from the deep cardiac plexus. At the junction of these nerves a 
 small ganglion, the cardiac ganglion of Wrisberg, is occasionally found, situ- 
 ated immediately beneath the arch of the aorta on the right side of the 
 ductus arteriosus (ligamentum arteriosum). This plexus lies in the con- 
 cavity of the arch of the aorta, and in front of the right pulmonary artery. 
 Branches from it pass to the 
 
 i Right Anterior Coronary Plexus, formed chiefly from the preceding, 
 also from the deep cardiac plexus. It passes forward between the 
 aorta and the pulmonary artery. It follows the ramifications of the 
 right coronary artery on the anterior surface of the heart. 
 Right and Left Anterior Pulmonary Plexuses, are formed by filaments 
 from the superficial and deep cardiac plexuses and the anterior pul- 
 monary branches of the vagus nerve. Branches from them accompany 
 the ramifications of the bronchial tubes throughout the lungs. The 
 Right and Left Posterior Pulmonary Plexuses are formed by the pos- 
 terior pulmonary branches of the vagus and branches from the 3rd 
 and 4th thoracic ganglia of the sympathetic. They are not con- 
 nected with the cardiac plexuses. They are situated on the pos- 
 terior aspect of the roots of the lungs, and their branches accompany 
 the ramifications of the bronchial tubes. 
 
 The Deep Cardiac Plexus is formed by the cardiac nerves derived 
 from the cervical ganglia of the sympathetic and the cardiac branches of 
 the recurrent laryngeal and pneumogastric nerves. The only cardiac 
 nerves which do not enter into its formation are those forming the super- 
 Seta! cardiac plexus, namely the left superior cardiac and the inferior 
 . cervical cardiac branches of the vagus. This plexus lies in front of the 
 bifurcation of the trachea and behind the arch of the aorta. Its branches 
 
240 HUMAN ANATOMY 
 
 on the right side pass in front and behind the right pulmonary artery 
 to the anterior pulmonary plexuses, the anterior (right) and posterior 
 (left) coronary plexuses, and the right auricle; those on the left side give 
 filaments to the superficial cardiac and anterior pulmonary plexuses and 
 the left auricle, and then form the greater part of the 
 
 Left or Posterior Coronary Plexus, is formed by filaments from both 
 sides of the deep cardiac plexus. It surrounds the branches of the 
 left coronary artery at the back of the heart, and its filaments are 
 distributed with those vessels to the muscular substance of the 
 ventricles. 
 Ganglia, are found on the cardiac nerves, both on the surface of the 
 
 heart and in its muscular substance. 
 
 ' The Epigastric (Cceliac) or Solar Plexus, sometimes called the abdomi nal 
 brain, consists of a great network of nerves and ganglia, situated behind 
 the stomach and in. front of the aorta and the crura of the diaphragm, 
 surrounding the cceliac axis and the root of the superior mesenteric artery. 
 Its principal ganglia are the two Semilunar (coeliac) Ganglia, irregular 
 gangliform masses, formed by the aggregation of smaller ganglia with 
 interspaces between them, situated one on each side of the plexus, and 
 in front of the crura of the diaphragm, close to the supra-renal capsules. 
 This plexus and its connected ganglia receive the great and small splanch- 
 jiic nerves of both sides, and some filaments from the right pneumogastric. 
 It distributes filaments over all the branches from the front of the 
 abdominal aorta, forming the following plexuses: 
 
 / Phrenic or Diaphragmatic Plexus, arises from the upper part of the 
 semilunar ganglion, and receives one or two branches from the phrenic 
 nerve. It accompanies the phrenic artery and supplies the dia- 
 phragm, some filaments going to the supra-renal capsule. At its 
 junction with the phrenic nerve on the right side is the 
 Ganglion Diaphragmaticum, a small ganglion at the juncture with 
 the right phrenic nerve, it is situated on the under surface of the 
 diaphragm, near the right supra-renal capsule. 
 
 . Supra-renal Plexus, is formed by branches from the solar plexus, the 
 semilunar ganglion, the phrenic and great splanchnic nerves. Its 
 branches are large, and supply the supra-renal capsule. 
 Renal Plexus, is formed by filaments from the solar plexus, the serai- 
 lunar ganglion, the aortic plexus, and the lesser and smallest splanch- 
 nic nerves, some 15 or 20 in all, which have numerous ganglia 
 on them. They accompany the branches of the renal artery into the 
 kidney, some filaments going to the inferior vena cava and to the 
 spermatic plexus. 
 
THE SYMPATHETIC SYSTEM 241 
 
 Spermatic Plexus is derived from the renal plexus and receives fila- 
 ments from the aortic plexus. It accompanies the spermatic vessels 
 to the testes. In the female it is called the Ovarian Plexus, and is 
 distributed to the ovaries and the fundus of the uterus. 
 
 Superior Gastric or Coronary Plexus, joins with branches from the 
 left pneumogastric nerve, and accompanies the gastric left artery along 
 the lesser curvature of the stomach, being distributed to that viscus. 
 
 Hepatic Plexus, receives filaments from the left pneumogastric and 
 the right phrenic nerves, accompanies the hepatic artery, and ramifies 
 in the substance of the liver upon the branches of that artery and those 
 of the portal vein. It gives off branches to all the divisions of the 
 hepatic artery, forming pyloric, gastro-duodenal, gastro-epiploic 
 (inferior gastric), and cystic plexuses, on the arteries similarly named. 
 
 /Splenic or Lienal Plexus, is formed by branches from the cceliac plexus, 
 the left semilunar ganglion, and the right pneumogastric nerve. 
 It accompanies the splenic artery and its branches to the substance 
 of the spleen, and gives off filaments to the pancreas and the left 
 gastro-epiploic plexus. 
 
 Superior Mesenteric Plexus, is a continuation of the solar plexus, and 
 receives a branch from the right pneumogastric nerve. It surrounds 
 the superior mesenteric artery, and divides into pancreatic, intes- 
 tinal, ileo-colic, right colic, and middle colic branches, which are 
 distributed to all the parts supplied by that artery. Its nerves have 
 numerous ganglia upon them near their origin. 
 
 Aortic Plexus, on the sides and front of the aorta, between the origins 
 of the superior and inferior mesenteric arteries; is formed by branches 
 from the solar (cceliac) plexus and semilunar (cceliac) ganglia, and 
 receives filaments from the lumbar ganglia. It sends branches to 
 the spermatic, inferior mesenteric, and hypogastric plexuses, also 
 some filaments to the inferior vena cava. A part of it is the 
 
 Inferior Mesenteric Plexus, divides into left colic, sigmoid, and superior 
 haemorrhoidal plexuses, and supplies the descending colon and the 
 rectum. 
 
 The Hypogastric Plexus is formed by filaments from the aortic plexus 
 and the lumbar ganglia, and is situated in front of the promontory of the 
 sacrum between the two common iliac arteries. It contains no evident 
 ganglia, and bifurcates into two lateral divisions, the Pelvic or Inferior 
 Hypogastric Plexuses, one on ea,ch side of the rectum, which receive branches 
 from the 2nd, 3rd, and 4th sacral nerves, and the first two sacral ganglia. 
 They give off numerous branches along the branches of the internal iliac 
 16 
 
242 HUMAN ANATOMY 
 
 arteries to the pelvic viscera, forming the following secondary plexuses, 
 viz. 
 
 Inferior Hamorrhoidal Plexus, to the rectum. 
 
 Vesical Plexus, to the bladder, vesiculae seminales, and vas deferens. 
 Prostatic Plexus, to that gland and the vesiculae seminales, also to the 
 
 erectile tissue of the penis as the large and small cavernous nerves. 
 Vaginal Plexus, to the vagina, gives off anteriorly the cavernous plexus 
 
 of the clitoris from which arise the greater and lesser cavernous 
 
 nerves of the clitoris. 
 Uterine Plexus, to the uterus and Fallopian tube. 
 
TABLES AND PLATES 
 
 OF THE 
 
 NERVOUS SYSTEM 
 
 NOTE. The folio-wing Tables are of original arrangement, and are designed to 
 show the origin, formation and distribution of each nerve. They are self-explana- 
 tory with the aid of the accompanying Plates. 
 
244 
 
 HUMAN ANATOMY 
 
 THE CRANIAL NERVES 
 
 I Ethmoidal foramina, 20, 
 
 ist NERVE, Olfactory. Function, smell. Exit, < in cribriform plate of 
 (See page 216) [ Ethmoid bone. 
 
 Ext. Root, Posterior division of the Rhin- | 
 
 encephalon or "Limbic lobe." istN. 
 
 Mid. Root, Optic thalamus. [ and 
 
 Int. Root, Posterior division of the Rhin- | Bulb. 
 
 encephalon or "Limbic lobe." 
 
 Ext. Filaments, to Schneiderian 
 membrane over sup. turbin- 
 al and ethmoid bones. 
 
 Int. Filaments, to Septum 
 (upper third). 
 
 Exit, Optic foramen. 
 
 2nd NERVE, Optic. Function, sight. 
 
 (See page 217) 
 
 This table is too long for the width of the page, and breaks at the Optic Commissure, 
 which is repeated again where the table continues below. 
 
 Optic thalamus 
 Ext. geniculate 
 Corp. quad. ant. 
 
 Corp. quad. ant. | 
 Optic thalamus J 
 
 | Longitudinal 
 Fibres -j Decussating 
 [ Commissural 
 
 \ Commissural 
 
 Left Optic Tract 
 
 ( Longitudinal J 
 
 OPTIC 
 
 COMMISSURE 
 or CHIASM. 
 
 OPTIC 
 
 COMMISSURE 
 or CHIASM. 
 
 [ Longitudinal, to temporal li of retina 
 
 Optic N. \ Decussating, fr. opp. tract to nasal Yt of ret. \ L. Eye. 
 [ Inter-retinal, fr. opp. retina to retina. 
 
 2d 
 
 f Inter-retinal, fr. opp. retina to retina. 
 
 Optic N. \ Decussating, fr. opp. tract to nasal te of ret. } R. Eye. 
 [ Longitudinal, to temporal J-i of retina. 
 
 3d NERVE, Motor Oculi. 
 
 (See page 217) 
 
 Nucleus in 1 
 floor of the 1 . . 
 Aqued.ofSyl. j 3 
 Crus cerebri. J 
 
 Function, motion. Exit, Sphenoidal fissure. 
 
 fSup. Branch, to Lev. palp, sup., Rectus superior. 
 . / to Rectus int., Rect. Inf., Inf. oblique. 
 Inf. Branch s L ' ... ' 
 ( motor root to Ciliary Ganglion. 
 
 Supplies all the muscles of the orbit (except the superior oblique and ext. rectus) , also 
 the sphincter of the iris and the ciliary muscle through the ciliary ganglion. 
 
 Function, motion. 
 
 Exit, Sphenoidal fissure. 
 
 4th NERVE, Trochlear. 
 (See page 217) 
 
 f to Sup. Oblique on upper (orbital) surface. 
 4th N. \ Branch to Cavernous Plexus of Sympathetic. 
 I Recurrent Branch, to lateral sinus. 
 
 Aq. of Sylvius. 
 Crus cerebri. 
 
 Is the smallest cranial nerve, with the longest nerve-course in the cranial cavity. 
 
THE CRANIAL NERVES 
 
 Plate 6 
 
 longitudinal Fibres 
 Decussating Fibres 
 Conuni&sura/Fibres _. 
 fnter-reiinul Fibr&r 
 
 PoKerdeL 
 
 245 
 
246 
 
 HUMAN ANATOMY 
 
 $th NERVE, Trigeminus. 
 (See page 218.) 
 
 Functions, Sensation, Motion. 
 
 
 (i) OPHTHALMIC 
 by Sphenoidal 
 fissure. 
 
 Frontal < 
 Lacrimal, to 
 
 Supraorbital. 
 Supratrochlear. 
 gland, etc. 
 Ganglionic. 
 Long Ciliary. 
 
 
 
 Nasal. 
 
 Infratrochlear. 
 
 
 
 Int. Nasal. 
 
 
 
 Ext. Nasal. 
 
 
 
 Meningeal. 
 
 Origin. 
 Nucleus and 
 
 
 
 /-> i'A t / Temporal. 
 Orbital, < ,, 
 [ Malar. 
 
 Locus Cae- 
 
 
 
 Spheno-palatine. 
 
 rul. in the 
 
 
 (2) MAXILLARY 
 
 Post. Sup. Denial. 
 
 medulla 
 oblongata 
 
 
 by For. rotund. 
 
 Mid Sup. Denial. \ . 
 Ant. Sup. Denial. / ' n canal - 
 
 for the 
 
 
 
 Palpebral, } 
 
 Sensory Root. 
 
 Nuclei in floor 
 of 4th Ven- 
 
 5th N. 
 Trigeminus 
 or Trifacial. 
 
 
 Nasal, > on the face. 
 Labial, J 
 
 Recurrent. 
 
 tricle, and 
 
 
 
 ( Ant. Br. * 
 
 Aq. of Syl- 
 
 
 
 Int.Pterygoid, j pQgt B ^. 
 
 vius, for the 
 
 
 
 Masseteric. * 
 
 Motor Root or 
 
 
 
 ( Ant. Br. * 
 
 Masticator 
 
 
 
 Deep Temporal j p os ^ ]} r> 
 
 Nerve. 
 
 
 
 Buccal. 
 
 
 
 Ext. Plerygoid.* 
 
 
 
 
 Br. to facial n. 
 
 
 (3) MANDIBU- 
 LAR. (including 
 masticator) by 
 For. Ovale. 
 
 A uriculo- 
 Temporal. 
 
 Br. to otic g. 
 Ant. Auricular. 
 to Meat. Aud. 
 to articulation. 
 Parotid. 
 
 
 
 Sup. Temporal. 
 
 
 Lingual 
 
 Br. of Comm'n. 
 Br. of Distrib'n. 
 
 
 
 Mylo-hyoid. * 
 
 
 Inferior 
 
 Dental Brs. 
 
 
 Dental. 
 
 Incisive. \ . . . 
 A , > terminal 
 Mental. J 
 
 Motor Branches (Masticator Nerve), going to the muscles of mastication. 
 
T r XT Plate7 
 
 THE CRANIAL NERVES. 
 
 5 l . h Nerve,-Trigeminus. 
 
 iotter.del 
 
 247 
 
248 
 
 HUMAN ANATOMY 
 
 7th NERVE, Facial, or Portio Dura. 
 (See page 220.) 
 
 Function, Motion, Special Sense (taste) 
 
 
 
 In auditory ' 
 canal. 
 
 > Br. to Auditory nerve. 
 
 
 
 
 Large Superf. Petrosal, to Meckel's 
 
 
 
 
 ganglion. 
 
 
 . 
 
 
 Small Superf. Petrosal, to otic 
 
 
 .0 
 
 In Aqueduct 
 
 ganglion. 
 
 
 1 
 
 of Fallopius. 
 
 Ext. Superf. Petrosal, to menin- 
 
 
 '% 
 
 
 geal plex. 
 
 
 a 
 
 
 
 
 Br. to Auricular of pneumogas- 
 
 
 g 
 
 
 tric. 
 
 
 o 
 
 
 
 
 O 
 
 
 
 Origin. 
 Nucleus in 
 floor of the 
 
 
 8 
 1 
 
 At exit from 
 the Stylo- 
 
 Br. to Great Auricular (cerv. 
 plex.). 
 Br. to Auriculo-Temporal (sth). 
 
 4th Ventricle, 
 and groove 
 
 
 o 
 
 a 
 
 rt 
 
 Foramen. 
 
 Br. to Pneumogastric. 
 Br. to Glosso-pharyngeal. 
 
 between 
 Olivary and 
 
 7th N. 
 Facial 
 
 W 
 
 Behind the 
 ear. 
 
 > Br. to small Occipital. 
 
 Restiform 
 
 facial 
 
 
 On the face. 
 
 Brs. to 3 divisions of the sth nerve. 
 
 bodies of 
 
 
 
 
 
 medulla 
 
 
 
 In the neck. 
 
 Br. to Superficial Cervical. 
 
 oblongata. 
 
 
 
 
 Solitary 
 
 
 
 Tympanic Nerve, to Stapedius 
 
 Tract. 
 
 
 
 In Aqueduct ^ 
 
 muscle. 
 
 
 e 
 
 of Fallopius. 
 
 Chorda Tympani Nerve (glosso- 
 
 
 | 
 
 
 palatine) , to the tongue and palate. 
 
 
 s . 
 
 "o 
 
 Near Stylo- 1 
 mastoid < 
 Foramen. 
 
 '/ Auricular. 
 Post. A uncular < _ . . . 
 \ Occipital. 
 
 Br. to Digastric muscle. 
 Br. to Stylo-hyoid muscle. 
 
 
 C/3 
 
 0) 
 
 
 
 
 S 
 
 
 ( Temporal. 
 
 
 d 
 
 2 
 
 f 
 
 Temporo-facial < Malar. 
 
 
 pq 
 
 1 
 
 { Infra-orbital. 
 
 
 On the face. * \ 
 
 
 
 (Buccal. 
 
 I 
 
 Mandibular. 
 
 r 
 
 Cervical. 
 
 * Forming the Pes A nserinus, or Goose's-foot, as these branches are named. 
 
THE CRANIAL NERVES. 
 
 7 1 ' 1 Nerve -Facial, or Portia Dura. 
 
 PlateS 
 
 References 
 
 1 LargeSuperf. Petrosal.toform VJlan wit 
 
 2 Small Supe^ PetrosaUo Optic Ganghor 
 
 3 External Superf. Fetrosal, to Plaus on M 
 
 4 Tympanic Br to Stapedius.etc. 
 
 3 Br n-om Carotid Plexus.Making Vidia^with NOf 
 ). 7. Eirs to Aur.culo -Temporal 5 
 V Br to Auricular of 
 
 24Q 
 
250 
 
 HUMAN ANATOMY 
 
 9th NERVE, Glossopharyngeal. Functions, Sensation, Special Sense. 
 (See page 221.) 
 
 
 Communica- j 
 
 Large Petrosal. 
 Small Petrosal. 
 
 
 ting Brs. to 1 
 
 Carotid Plexus. 
 
 Clrioiti ^ 
 
 1 ympantc or 
 
 
 
 LJrigin. 
 Tractus soli- 
 tarius and floor 
 
 pth Nerve 
 Glosso- 
 
 Jacobson's N. 
 
 Distributing I 
 
 Fenestra vestibuli. 
 Fenestra cochlea?. 
 
 of 4th vent. 
 
 pharyn- 
 
 
 Brs. to 
 
 Eustachian tube. 
 
 and the 
 
 geal, by 
 
 Carotid Branches, along Int. Carotid artery. 
 
 medulla oblong. 
 
 Jugular 
 
 Pharyngeal Br. to Pharyngeal Plexus. 
 
 behind the 
 
 Foramen. 
 
 Muscular Br. to Stylo-pharyngeus. 
 
 olivary body. 
 
 Tonsillar Brs. to Tonsillar Plexus. 
 
 Lingual Brs. to base and posterior ^ of tongue; 
 
 
 nerve of taste. 
 
 
 loth NERVE, Pneumogastric, or Vagus. Function, Motion, Sensation. 
 
 (See page 221.) 
 
 
 
 Meningeal, to dura mater. 
 
 
 
 Auricular (Arnold's Nerve), to external ear. 
 
 
 Pharyngeal, to that plexus. 
 
 
 Origin. 
 
 Funic. soli- 
 
 
 Sup. Laryngeal < T Xt ' T aryng ' 
 ( Int. Laryng. 
 
 crico-thyroid). 
 supplies all the 
 
 tarius, nucleus 
 
 
 
 laryngeal 
 
 ambiguus, floor 
 
 loth Nerve 
 
 Recurrent Larynpf-f-l 
 
 muscles except 
 
 of 4th ventricle 
 
 Vagus, by 
 
 Cervical Car- 
 
 
 crico-thyroid and 
 
 and the medulla 
 
 Jugular 
 
 diac. 
 
 to cardiac 
 
 arytenoideus. 
 
 oblongata be- 
 
 Foramen. 
 
 Thoracic Car- 
 
 plexus. 
 
 
 tween olivary 
 
 
 diac. 
 
 
 
 and restiforn 
 bodies. 
 
 
 Ant. Pulmonary. \ 
 -. , /-to pulmonary plexus. 
 Post. Pulmonary. } 
 
 (Esophageal, to that plexus. 
 Gastric Brs., to the stomach. 
 Hepatic, to the hepatic plexus. 
 
 terminal brs. 
 
 Gives sensation to external ear and larynx, motion to other parts, also vaso- 
 motor, inhibitory, trophic and secretory influences. A nerve of deglutition, phona- 
 tion, respiration, circulation, and digestion. The Auriculo-Laryngo-Pharyngo- 
 CEsophago-Tracheo-Pulmono-Cardio-Gastro-Hepatic Nerve. 
 
 nth NERVE, Spinal Accessory (N. ACCESSORIUS). 
 (See page 222.) 
 
 Function, Motion. 
 
 Origin. 
 
 Floor of 4th 
 
 ventricle, and 
 
 gray horn of 
 
 cord, down to 
 
 6th Cervical N. 
 
 nth Nerve, 
 by Jugu- 
 lar Fora- 
 men. 
 
 Branches, to Pharyngeal and Sup. Laryngeal of 
 Vagus. 
 
 Internal, anastomosing with Vagus, is probably 
 the Recurrent Laryngeal Br. of the latter nerve. 
 
 / Sterno-mastoid. 
 External, or Muscular, tos _ 
 
 ^ Trapezius. 
 
 A motor nerve to the muscles named, and probably to the larynx also. 
 
Plate 9 
 a, THE CRANIAL NERVES. 
 
 9'.* or Glosso- pharyngeal, 
 I0 l . h or Pneumo gastric, 
 II fc . h or Spinal Accessory. 
 
 References. 
 
 IJugular Ganglion of 3 th Nerve 
 
 Z.Petroui Ganglion of 9 th Nerve 
 
 3.Ganglion of the Vagu5 Rook. 
 
 4. Ganglion of the Vagus Trunk. 
 
 5. Medullary part OF IP* Nerve. 
 
 6.Spinal part of ||f." Nerve. 
 
 7 Sup Cardiac Br JOINING Cardiac of 5ympafhetic 
 
 8.5ubclavian Artery on right side, Arch of the 
 
 Aorla on left side of the body. 
 9.Foramcn Magnum, receiving 5pinaf part of 
 
 the Spinal Accessory. 
 
 10. Jugular Foramen.transmitl'ng all three Nerves 
 II Branches to the Hypooloisal Sympathetic 
 
 cervical fierves ' 
 12. Olivary body, (in broken line). 
 
 Potter.del. 
 
 251 
 
252 
 
 HUMAN ANATOMY 
 
 6th NERVE, Abducens (see page 219). 
 
 Origin. A nucleus 
 
 in floor of 4th ven- 
 tricle, and the ^6th Nerve, Abducens. 
 pyramid of the 
 medulla oblongata. 
 
 Function, Motion. 
 
 Exit by sphenoidal fissure to the 
 Ext. Rectus muscle of the eyeball. 
 Branch, to the sympathetic. 
 
 8th NERVE, Auditory, OR ACUSTIC. 
 
 Function, Special Sense. 
 
 Origin. Striae in 
 
 floor of the 4th 
 
 ventricle, and 
 
 groove between 
 
 the pons and 
 
 medulla. 
 
 8th Nerve, 
 Auditory. 
 
 f 2 Semi-circ. canals. 
 Vestibular, toj Utricle. 
 [ Saccule. 
 
 J Post. Semi-circ. canal. 
 Cochlear, to \ Saccule and Utricle. 
 
 1 Cochlea, and Organ of Corti. 
 
 A nerve of special sense (hearing), described on page 220, ante. It goes by the 
 Internal Auditory Meatus, through the Internal Auditory Canal, to the internal ear. 
 It is the only cranial nerve which does not leave the cranial wall. 
 
 i2th NERVE, Hypoglossal (NONUS OR QTH OF WILLIS). 
 
 (See page 222.) Function, Motor of tongue, etc. 
 
 Brs. to 
 
 Origin. Floor of 
 4th ventricle, and 
 groove between 
 the pyramid and 
 olivary body of 
 medulla. J 
 
 1 2th Nerve, 
 Hypoglossal. 
 
 Descendens 
 Hypoglossi. 
 
 / Lingual of 5th. 
 Communicating I Symphatic. 
 I i, 2 Cervical. 
 ( Vagus. 
 
 IBr. to Sterno-hyoid. 
 Br. to Sterno-thyroid. 
 Br. to Omo-hyoid. 
 Joins Communicans Hypo- 
 glossi. 
 
 Thyro-hyoid, to that muscle. 
 
 Muscular, to 
 
 j Stylo-glossus. 
 I Hyo-glossus. 
 I Genio-hyoid. 
 [ Genio-hyo-glossus. 
 
 Exit, by Ant. Condylar foramen (Canalis hypoglossi). 
 
THE CRANIAL NERVES. 
 
 6 th Nerve,- Abducens. 
 
 to RectErter 
 
 Plate 10 
 
 r ia al .Nerve^ of ^ 
 
 J& ^ 
 
 1 2** Nerve, - 
 
 Hypoglossal 
 (Nonus or 9^ of Willis) 
 
 .5**' 
 Infra. 
 . 3upnz-, , 
 
 4 Aunculo-temporal.SW 
 
 5 Lachry 
 
 7. 
 
 ., 
 9. Ibstertor Auricular??* 
 
 V 
 
 Rjtter del 
 
 253 
 
 and 0mo- 
 
254 
 
 HUMAN ANATOMY 
 
 THE SPINAL NERVES 
 
 8 CERVICAL, 12 THORACIC, 5 LUMBAR, 5 SACRAL, i COCCYGEAL 
 N. B. Read from the Black Type outwards to left and right 
 
 
 
 Brs 
 
 3, to Recticap. Muscles. 
 
 Post Div. of 2d N. 
 
 
 2 Cerv. N. 
 
 Post M. of head, etc. POST. ] ist Cerv 
 
 cal | ANT. Commun'g Vagus N. 
 
 Complexus Muscle. Div. \ Nerve. 
 
 j Div. Brs. to | Hypogl. N. 
 
 Skin of occiput. 
 
 J Sub-occij 
 
 pital ( 
 
 Sup. Cerv. 
 
 
 
 
 Gang. 
 
 
 
 Br. 
 
 to Occip-atloid artic'n. 
 
 Splenius 
 
 
 
 
 Cerv. ascendens 
 
 
 
 
 Transv.-colli 
 
 Ext. Branch 
 
 
 Br. to Spinal accessory 
 
 Trach-mastoid 
 
 supplying 
 
 
 Fil.to Sterno-mastoidM. 
 
 Complexus 
 
 POST. 
 
 . ANT. 
 Cervical 
 
 Asc. Br. to ist Cerv. N. 
 Desc. Br. to 3d Cerv. N. 
 
 to ist Cerv. N. 
 
 )lnt. Br. or 
 
 Nerve. 
 
 Fil. to Commun. Hyp. 
 
 Skin of occiput. 
 
 Great Occip. 
 
 
 Occipitalis Minor N. 
 
 Auricular. 
 
 
 
 
 
 
 
 Auric. Magnus N. 
 
 Splenius 
 
 
 A seen 
 
 Superf. Cervical N. 
 
 Cerv. ascend. 
 
 Ext. Br. 
 
 Br. 
 
 Br. to 2d Cerv. N. 
 
 Trans, colli 
 
 supplies 
 
 
 Br. to Spinal-ac. 
 
 Trach-mast. 
 
 POST. 1 . 3d 
 n.,, Cervic 
 
 , ANT. 
 al I Div. 
 
 Fil. to 4th Nerve. 
 
 ] Int. Br. ""' 1 Nerv 
 Integument 1 
 
 of occiput. J 
 J supply 
 
 e. J Descen. Fil. to Lev. ang. scap. 
 Br. Supra-clavicular. 
 Fil. to Com. Hypogl. 
 
 
 
 
 Fil. to Phrenic N. 
 
 
 
 Fil. to 3d Cerv. N. 
 
 . / POST. \ 4th Cervi 
 Muscles of the Back, f ^_ > XT 
 
 -al f ANT FU " tO 5th CerV ' N> 
 D.v 1 FiL to Phrenic N " 
 
 
 ^ i-iv. j nerve. 
 
 Fil. to Scalenus medius. 
 
 
 
 I Fil 
 
 to Supra-clavic. N. 
 
 A nterior 
 Divisions of 
 ist Cerv. N. 
 2d Cerv. N. 
 3d Cerv. N. 
 4th Cerv. N. 
 
 Cervical 
 Plexus. 
 
 Superficial 
 
 Deep Brs. 
 
 (See page 227.) 
 
 Occipitalis Minor, to head. 
 
 I Facial. 
 Auricularis Magnus j Auricular. 
 
 ( Mastoid. 
 Superficialis Colli, has 2 branches. 
 
 I Vagus. 
 Communicating to j Hypoglossus. 
 
 | Sympathetic. 
 
 Muscular, to ant. rectus and rect. later. 
 Communicans Hypoglossi N. 2. 
 Phrenic Nerve, to the diaphragm. 
 Muscular 4, to Sterno-mastoid, etc. 
 [ Communicating, to Spinal accessory. 
 
THE SPINAL NERVES. Hate 11 
 
 Cervical Plexus. 
 
 Potter .del 
 
 /lCfo/r/fff{ 
 
 The Cervical Plexus 
 
 i... iu ( Scalenus Medius and \ . 
 
 lies upon the Muscles 
 
 ILevator anguli Scapulae I 
 is covered by the Sterno-Cleido-Mastoid Muscle 
 
 255 
 
256 
 
 HUMAN ANATOMY 
 
 o 
 
 THE BRACHIAL PLEXUS 
 (See page 228.) Communicating Br. to phrenic nerve. 
 
 Post, or Long Thoracic, I to 
 the Ext. Respiratory I Serrat. 
 N. of Bell. { mag. 
 
 , f Supra-spinatus. 
 Supra-scapular, T , . 
 ^ < Infra-spmatus. 
 
 I Shoulder-joint. 
 Rhomboidei (5, 6, Cerv.) 
 Subclavius (5, 6. Cerv.) 
 Scaleni (6, 7, Cerv.) 
 Long, colli (6, 7, Cerv.) 
 Lev. ang. scap. (5, Cerv.) 
 
 Ant. Div. 
 
 5th 
 Cervical 
 
 Nerve. 
 
 Ant. Div. 
 
 6th 
 
 Cervical 
 Nerve. 
 
 Ant. Div. 
 
 7th 
 
 Cervical 
 Nerve. 
 
 Ant. Div. 
 
 8th 
 
 Cervical 
 Nerve. 
 
 Ant. Div. 
 
 ist 
 
 Thoracic 
 Nerve. 
 
 UPPER 
 PRI- 
 MARY 
 CORD. 
 
 LOWER 
 
 PRI- 
 
 MARY 
 
 Brach- 
 ial 
 Plexus, i 
 
 OUTER 
 or LAT- 
 ERAL 
 CORD. 
 
 to 
 
 Muscu- 
 lar, to 
 
 POSTERIOR 
 CORD. 
 
 INNER or 
 MEDIAL 
 CORD. 
 
 f Br. to Post. Cord of Brachial Plexus. 
 External Ant. Thoracic, to Pect. 
 major. 
 
 f Muscular. 
 
 Musculo-cutaneous. I Anterior. 
 (No. 2.) | Posterior. 
 
 [ Articular. 
 Median Nerve (outer head) (No. 3). 
 
 ist Sub scapular, to Subscap. M. 
 2d Subscapular, to Lat. dorsi. 
 3d Scapular, to Teres major. 
 Circumflex, to Deltoid and skin. 
 (n. Axillaris.) 
 
 Musculo-spiral f Muscular < 
 (No. 6). 
 (n. Radialis.) 
 
 Cutaneous. 
 
 Muscular, 
 to 
 
 Post. Interosseous. 
 
 [ Scaleni (8, Cerv.) 
 | Long, colli (8 Cerv.) 
 I Above Clavicle. 
 Br. to Post. Cord of Brachial Plexus. 
 Int. Ant. Thoracic, to Pectoral 
 
 muscles. 
 Internal Cutaneous (No. 8) (medial 
 
 Anti-brachial cutaneous). 
 Lesser Int. Cutan. (N. of Wrisberg) 
 
 (medial brachial cutaneous). 
 Median Nerve (inner head) (No. 3). 
 Ulnar Nerve (No. 10). 
 
 Note. Nos. i, 2, 3, etc., refer to the next two tables. 
 
THE SPINAL NERVES 
 
 Brachial Plexus 
 
 Ulament from 
 
 Plate 12 
 
 Cv 
 
 /. Three <Sub- scapular JVerm. 
 2. Internal Ant. Thoracic. 
 
 Potter del 
 
 Jtfusculo-cutaneous 
 'Median. 
 
 Wnar 
 
 Jnternal-culaneouj 
 
 The Brachial Plexus is 
 in the Neck and the Axilla, 
 lym^ between the Anterior 
 and Middle Scaleni muscles 
 at first- then below the Sub- 
 clavius and upon the 1^ 
 serration of theSerratus 
 Magnus and Subscapulans. 
 It is on both sides of. and 
 behind the Axillary Artery 
 in its 2 nd Portion, external 
 .thereto in its I st Portion. 
 
 17 
 
 257 
 
258 
 
 HUMAN ANATOMY 
 
 NERVES OF THE UPPER EXTREMITY 
 
 TERMINAL BRANCHES OF THE BRACHIAL PLEXUS 
 
 
 (i) EXTERNAL ANTERIOR THORACIC, to Pectoralis major muscle. 
 
 
 f Coraco-brachialis. 
 
 
 
 Muscular, to.. { Biceps. 
 
 
 
 [ Brachialis anticus. 
 
 i 
 
 
 f Skin of forearm (front). 
 
 8 
 
 
 Anterior Br. -1 Skin of ball of thumb. 
 
 1 
 
 (2) MUSCULO- 
 
 { Joins Radial Nerve. 
 
 
 CUTANEOUS. 
 
 
 a 
 
 
 
 Skin of forearm (back). 
 
 1 
 
 
 Posterior Br. 
 
 Joins Radial Nerve. 
 Joins Ext. Cutan. Br. of Musculo- 
 
 3 
 
 
 
 spiral N. 
 
 -8 
 
 
 Articular Br., to Elbow- joint. 
 
 o 
 
 f Pronator radii teres. 
 
 | 
 
 
 Muscular, to . . 
 
 Flex, carpi radialis. 
 Palm, longus. 
 
 
 
 ' 6 
 
 
 Flex. subl. digitorum. 
 
 
 
 \ 
 
 1 
 c 
 
 A nterior 
 Interosseous. 
 
 to Flex. long, pollicis. 
 to Flex. prof, digit. (Ext. H). 
 to Pronat. quadratus. 
 
 
 
 
 Palmar I Skin of palm. 
 
 
 
 
 Cutaneous. \ Skin of ball of thumb. 
 
 
 (3) MEDIAN, from 
 
 
 
 both outer and 
 
 
 to Abduct, pollicis. 
 
 
 inner cords. 
 
 
 to Opponens pollicis. 
 
 
 A 
 
 External Br... 
 
 to Flex. brev. pollicis. 
 
 
 
 
 
 Digital, to thumb. 
 
 
 W 
 
 
 Digital, to ist finger. 
 
 
 V 
 
 
 
 a 
 
 c 
 
 
 Digital, to contiguous sides of in- 
 
 
 M 
 
 Internal Br. .. 
 
 dex, middle and ring fingers. 
 Filaments, to two outer Lum- 
 
 
 bricales. 
 
THE SPINAL NERVES. Piste 13. 
 
 250 
 
26o 
 
 HUMAN ANATOMY 
 NERVES OF THE UPPER EXTREMITY. Continued. 
 
 ist, Upper, to Subscapular muscle. 
 U)SuBSCAPULAR3 { 2d, Long, to Latiss. dorsi. 
 3d, L'ower, to Teres major. 
 
 (5) CIRCUMFLEX 
 (n. Axillaris). 
 
 / Deltoid. 
 
 Superior Br..to < , . , 
 \ Skin of i 
 
 Skin of shoulder. 
 
 Teres minor. 
 
 Inferior Br..to -j Deltoid (posteriorly). 
 Skin of shoulder. 
 
 (6) MUSCULO- 
 SPIRAL (n. 
 Radialis). 
 
 Muscular ... to 
 
 f Triceps. Anconeus. 
 I Brach. anticus. 
 I Supin. longus. 
 [ Extensor carpi long. 
 
 Cutaneous, to skin of arm. 
 
 f External Br. to skin of thumb. 
 
 Radial, 
 
 ] Internal Br. 
 
 I to ulnar side of thumb and ad- 
 \ jacent sides of 2^ fingers. 
 
 ito all muscles on back of forearm, 
 except Anconeus, Sup. long, and 
 Extensor carpi longior. 
 Filaments to wrist-joints. 
 
 (7) INTERNAL ANTERIOR THORACIC, to both Pectoral muscles. 
 
 (8) INTERNAL CUTANEOUS ( Anterior Br. to skin of forearm, inner side, 
 (med. Ant. Brach. Cuta.) \ Posterior Br. to skin of forearm, inner side. 
 
 (9) LESSER INTERNAL CUTANEOUS, f Is often wanting, Intercosto-humeral 
 
 (N. of Wrisberg.) -j taking its place, to post, surface of 
 
 (medial Brach. Cutan.) 1 lower H of skin of arm. 
 
 
 Articular, . . 
 
 . . to Elbow-joint. 
 
 
 
 i 
 
 Muscular, . . 
 
 f Flex. carp, ulnaris. 
 ' \ Flex. prof. dig. (inner }) 
 
 
 
 8 
 
 ' 
 
 c 
 
 Cutaneous, to skin of front wrist, and palm of hand. 
 Dorsal Cutaneous, to skin of back wrist, and iji fingers. 
 
 (10) ULNAR 
 
 
 Articular, . . . 
 
 . to Wrist-joint. 
 
 
 
 i 
 
 rt 
 
 a 
 i i 
 
 Superficial 
 Palmar, , . . 
 
 ( Palmaris brevis. 
 to\ Skin of iH fingers. 
 
 (Muscles of little finger. 
 2 inner Lumbricales. 
 
 InterosseL 
 
 Dt.r.t "Pn.lm.nv 
 
 Adduc. pollicis. 
 
 Flex. brev. poll, (inner headV 
 
THE THORACIC NERVES 
 
 26l 
 
 THE THORACIC NERVES 
 
 N. B.Read from the Black Types outwards to left and right 
 
 Transv. colli. 
 
 
 
 Muscu- { Intercos. 
 
 Longis. dorsi. 
 
 
 
 lar. \ Tri. Ster. 
 
 Trachelo-mast. 
 
 Ext. Brs. 
 
 
 
 
 
 Levat. costar. 
 
 < to 
 
 
 
 
 Skin of 
 
 Sacro-lumbal. 
 
 
 { Each of 1 
 
 ANT. 
 
 Lateral 
 
 Chest, 
 
 Aocessorius. 
 
 
 POST.) Upper 6 1 
 
 Div. 
 
 Cutane- 
 
 Breast. 
 
 
 
 Div. | Thoracic | 
 
 Thoracic 
 
 ous. 
 
 Side, 
 
 
 
 I Nerves. J 
 
 Inlercostals. 
 
 
 Back. 
 
 Semi-sp. dorsi. 
 
 r Int. Brs. 
 
 
 
 A nterior 
 
 f Skin of 
 
 Multif. Spinae. 
 
 tO 
 
 
 
 Cutane- < 
 
 Chest, 
 
 Skin of back. 
 
 
 
 ous. 
 
 , Breast. 
 
 
 
 
 Muscu- ( Intercos. 
 
 Same as above. 
 
 . Z7..J D - 
 
 ANT. 
 
 lar. \ Abdom. M. 
 
 Skin of back. 
 
 * iLxt. &rs. 
 
 
 Div. or 
 
 
 
 
 
 (Each of 1 
 
 Thorac- 
 
 Lateral ( Skin of 
 
 
 
 Lower 6 1 
 
 ico-ab- 
 
 Cutane- j 
 
 Abdomen, 
 
 
 
 Thoracic J 
 
 dominal 
 
 ous. { etc. 
 
 Same as above. 
 
 \, 
 
 Nerves. J 
 
 Inter- 
 
 
 
 No. br. of skin. > 
 
 > Int. Brs. 
 
 
 costal*. 
 
 Anterior ( Recti M. 
 
 
 
 
 Cutane- j Skin of 
 
 
 
 
 ous. 
 
 Abdomen. 
 
 1 2th 
 Thoracic 
 
 ANT. Div. 
 
 /Also sends a branch to 
 1 the Lumbo-sacral Cord. 
 
262 
 
 HUMAN ANATOMY 
 THE LUMBAR AND SACRAL NERVES 
 
 (See page 232) 
 (DISTRIBUTION SHOWN ON THE NEXT TWO TABLES) 
 
 An | 1 
 
 [ Nos. 
 
 
 ^^ Branch, g Ist Lumbar / Ant. i, 2, 3, 
 sending filaments > [ Div. | Comm. Br. 
 
 
 to the Erector g J 
 
 ( to 2d Lum. 
 
 
 spinae and o 
 
 
 
 Intertransversales JB 1 
 
 Nos. 
 
 
 muscles, and the ^ 
 skin of the gluteal ^ Lumba, 
 
 . f Ant. 3, 4, 7, 
 \ Div. Comm. Br. 
 
 
 region, posteriorly. ^ J 
 
 to 3d Lum. 
 
 Lumbar Plexus. 
 
 3 
 
 
 Branches: 
 
 1 1 
 
 {Part of 
 
 (i) Ilio-hypogastric. 
 
 
 5, 6. 7, 
 
 (2) Ilio-inguinal. 
 
 Internal Branch, -J3 | 3 
 
 Comm. Br. 
 
 (3) Genito- crural. 
 
 sending filaments Q J 
 
 to 4th Lum. 
 
 (4) Ext. Cutaneous. 
 
 to the Multifid. ^ 
 
 
 (5) Obturator. 
 
 spinae, and Inter- -g 
 
 f Part of 
 
 (6) Accessory 
 
 spinales, and the -g 
 skin over spinal j- 4th Lumba 
 
 /Ant. r 5 'V 
 r. < ^. Lumbo- 
 
 Obturator. 
 (7) Anterior Crural. 
 
 vertebras. <u 
 
 * 1V ' 5acra/ 
 
 
 e J 
 
 Cord 
 
 
 \ 
 
 r A., f Joins the ' 
 
 
 g [ 5th Lumbar. < ""T { Lumfeo- 
 
 
 4 - J 
 
 [ Sacra/ Cora 1 
 
 
 External Branch, 
 
 
 
 forming loop on 
 
 f Joins the 
 
 
 sacrum and great c 
 
 / Ant Lumbo- 
 
 
 Sac-Sciat. lig. to g ist Sacral. 
 
 1 nj^ Sacra/ Cord 
 
 
 supply skin over 
 
 I L'lv. j 
 and 
 
 
 glutei. "3 
 
 2d Sacral. 
 
 
 * [ad Sacral. 
 "8 
 
 / Ant. / Joins with 
 \ Div. \ ist Sacral. 
 
 Sacral Plexus. 
 
 Branches: 
 
 a 
 
 
 (i) Sup. Gluteal. 
 
 An 1 
 
 f Joins with 
 
 (2) Inf. Gluteal. 
 
 Internal Branch, > I 
 to Multifidus Spinae S | 3d 
 
 2d Sacral 
 and part 
 
 (3) Muscular. 
 (4) Articular. 
 
 and skin of the J 
 
 [ of the 4th. 
 
 (5) Small Sciatic. 
 
 gluteal region; the % 
 
 
 (6) Pudic. 
 
 lower nerve to g 
 
 Br. to 
 
 (7) Great Sciatic. 
 
 Extensor Coccygis & 
 
 f Ant PleXUS> 
 
 
 and skin over the jg 4th Sacral. 
 
 i Div Visc ' Brs - 
 
 
 coccyx. 
 
 Mus. Brs. 
 
 
 J 
 
 Fil. to 5th. . 
 
 
 Join together in 
 
 
 loops over back Post. \ 
 of sacrum, Div./ 5 * SaCraL 
 
 / Ant. ( Br. to skin of coccyx. 
 \ Div. j Br. to Coccygeus M. 
 
 sending fila- 
 
 [ Br. to Cocc. Nerve. 
 
 ments to skin 
 
 
 over coccyx Post. \ _ 
 
 f Ant. / A delicate filament, going to skin 
 
 and Extensor Div. / 
 
 \ Div. \ over coccyx. 
 
 Coccygis. 
 
 
Plate 14 
 
 THE SPINAL NERVES. 
 
 lumbar & Sacral Plexuses. 
 
 The lumbar Plexus lies in the Substance of the Psoas Muscle 
 ( Lies upon the Pyr iformis Muscle in the Pelvis 
 
 The Sacral Plexus {and is covered by the Pelvic Fascia, and the 
 V Sciatic and Pudic Arteries. 
 Potter, del 
 
264 
 
 HUMAN ANATOMY 
 
 ILIO-HYPOGASTRIC, 
 from ist Lumbar. 
 
 DISTRIBUTION OF THE BRANCHES 
 FROM THE 7 GREAT TRUNKS OF THE LUMBAR PLEXUS 
 (A CONTINUATION OF THE TABLE ON PAGE 261) 
 
 f Iliac, to skin of gluteal region. 
 
 j Hypogastric, to skin of that region. 
 
 ( Communicating Br., with I2th thoracic nerve. 
 
 ILIO-INGUINAL, 
 
 from ist Lumbar. 
 
 Branch, to ilio-hypogastric nerve. 
 
 to Internal Oblique muscle. 
 
 to skin of upper and inner thigh, scrotum. 
 
 GENITO-CRURAL, \ Genital, to Cremaster, scrotum, round ligament, 
 
 or GENITO-FEMORAL <j Crural, to skin of upper and front thigh, 
 from ist, 2nd Lumbar. [ Branch, to femoral artery. 
 
 EXTERNAL CUTANEOUS, ( Ant. Br. to skin of ant. and outer thigh, 
 from 2nd, 3d Lumbar. \ Post. Br. to skin of post, and outer thigh. 
 
 OBTURATOR, 
 from 2d, sd 
 4th Lumbar. 
 
 Ant. I" Articular Brs. to hip-joint. 
 Br. j Muscular Brs. to Adductors, Gracilis and Pectineus. 
 
 [ Anastotnotic Brs. with Int. Cutan. and Int. Saphenous. 
 
 Post. \ Articular Brs. to knee-joint. 
 Br. \ Muscular Brs. to Adduc. mag. and Obturator externus. 
 
 ACCESSORY OBTURATOR, 
 
 from 3d, 4th Lumbar. 
 
 Muscular Br. to Pectineus. 
 Articular Br. to hip- joint. 
 
 f often absent. 
 
 Cutaneous Br. to skin of thigh and leg. J 
 Muscular Brs. to Iliacus muscle. 
 
 Arterial, to the femoral artery. 
 
 > within abdomen. 
 
 ANTERIOR 
 
 
 Mid. Cutaneous. 
 
 to Sartorius, and skin of ant. thigh 
 as low as the knee. 
 
 FEMORAL or 
 
 Ant. 
 
 
 Ext. Br. to skin, lateral of knee. 
 
 CRURAL, 
 
 Div. 
 
 Int. Cutaneous. 
 
 Post. Br. to skin of inner thigh and 
 
 from 2d, 3d, 
 
 
 
 leg. 
 
 4th Lumbar. 
 
 
 Long Saphenous. 
 
 to skin of knee and of front and 
 inner leg and foot. 
 
 
 p | Muscular Brs. to the 4 parts of the Quadriceps Extensor 
 
 
 *T j muscle. 
 
 
 V ' [ Articular Brs. 2, to capsules of knee- and hip-joints. 
 
 The Lumbar Plexus lies in the substance of the Psoas muscle, in front of the trans- 
 verse processes of the lumbar vertebrae. 
 
THE SPINAL NERVES. 
 
 Plate 15 
 
 Potter, del 
 
266 
 
 HUMAN ANATOMY 
 
 DISTRIBUTION OF THE BRANCHES OP THE SACRAL PLEXUS 
 [CONTINUATION OF TABLE ON PAGE 261] 
 
 SUPERIOR GLUTEAL, 
 from Lumbo-sacral cord. I Inf. Br. 
 
 Sup. Br. to the Gluteus medius muscle. 
 
 to the Gluteus medius and minimus, 
 to the Tensor vaginae femoris. 
 
 INFERIOR GLUTEAL,. .to the Gluteus maximus muscle. 
 
 MUSCULAR BRANCHES, to 
 
 Pyriformis, Obturator internus, the two Gemelli, and 
 
 the Quadratus femoris muscles. 
 ARTICULAR BRANCHES, to the hip- joint. 
 
 SMALL SCIATIC, 
 or POSTERIOR 
 FEMORAL 
 CUTANEOUS, 
 from 2d, 3d Sac- 
 ral. 
 
 Gluteal Cutaneous, to skin over Gluteus maximus. 
 
 Perineal Cutaneous, * ^ * " P f ^ and f inner thigh ' 
 [ Inf. Pudendal, skin of scrotum. 
 
 Femoral Cutaneous 
 
 back f thigh, popliteal space, and 
 upper part of the leg. 
 
 PERFORATING f 
 
 CUTANEOUS, 1 to skin covering lower part of Gluteus maximus muscle: passes 
 
 from 2d, 3d Sac- ] through the sacro-sciatic ligament. 
 ral. 
 
 PUDIC or 
 PUDENDAL, 
 from 3d, 4th 
 Sacral. 
 
 GREAT SCIATIC 
 (n. ischiadicus), 
 from lumbo-sac- 
 ral cord, 4 upper 
 sacral. 
 
 Inferior Hemorrhoidal, 
 
 to Sphincter ani muscle, 
 to skin of anal region. 
 
 (to Skin of anus, scrotum, 
 Superficial Perineal, -j penis and labia, and the 
 ( Sphincter ani muscle. 
 Muscular, to perineal muscles, and corpus spongio- 
 sum of penis. 
 
 Dorsal of Penis, 
 
 Skin of dorsum of penis. 
 Br. to Corpora cavernosa. 
 
 Articular,, .to the hip-joint. 
 
 Adductus magnus, Biceps. 
 
 Muscular, to 
 
 Semi-mem branosus, Semi-tendinosus. 
 
 External Popliteal or Peroneal. \ terminal branches. 
 
 Internal Popliteal or Tibial Nerve. } (See next page.) 
 
 The Sacral Plexus lies in the pelvis upon the Pyriformis muscle, and is covered 
 by the Pelvic fascia, and the Sciatic and Pudic arteries. 
 
NERVES OF THE LEG AND FOOT 
 
 267 
 
 INTERNAL 
 
 POPLITEAL 
 
 or TIBIAL 
 
 NERVE. 
 
 NERVES OF THE LEG AND FOOT 
 
 TERMINAL BRANCHES OF THE GREAT SCIATIC NERVE] 
 Articular 3, to knee-joint. 
 
 Muscular, to Gastrocnemius, Plantaris, Soleus, and Popliteus. 
 Communicans Tibialis, to form the Ext. Saphenous nerve. 
 
 I formed by a filament from each of the 
 
 External or Short Saphenous, j Popliteal nerves, to skin of outer 
 1 side of the foot and little toe. 
 
 Continues 
 as the 
 
 POSTERIOR 
 TIBIAL. 
 
 Muscular, to 
 
 Flexor longus pollicis. Flexor longus digitorum. 
 
 Tibialis posticus. Soleus. 
 Calcaneo-Plantar, to skin of heel and sole of the foot. 
 Articular, to the ankle-joint. 
 
 I Digital, to skin, 3^ inner toes. 
 Internal I Muscular, to flexors, etc. 
 
 Plantar. J Articular, to tarsal joints. 
 I Cutaneous, to sole of foot. 
 
 External 
 Plantar. 
 
 Muscular, to Flexor accessorius. 
 
 f to I ^j outer toes. 
 Superficial, < Flexor brevis min. digiti. 
 
 [ 4th Interosseous. 
 
 Deep Br. to the 
 
 3d and 4th Lumbricales. 
 rest of Interossei. 
 
 EXTERNAL 
 POPLITEAL 
 or COMMON 
 PERONEAL 
 NERVE. 
 
 Articular 3, distributed to the knee-joint. 
 Cutaneous 2, to skin of leg, exteriorly and posteriorly. 
 Communicans Peronei, to form the Ext. Saphenous nerve. 
 / front muscles of leg. 
 
 Anterior 
 Tibial cr 
 Deep Pero- 
 neal 
 
 Musculo- 
 cutaneous or 
 Superficial 
 Peroneal. 
 
 Muscular, to 
 
 External Br. 
 
 \ Peroneus tertius. 
 
 / Extensor brevis digitorum. 
 
 \ Tarsal articulations. 
 Internal Br. to skin of sides of great and 2nd toes. 
 
 External Br. 
 
 Peroneus longus and brevis muscles. 
 Skin, outer side of foot and ankle. 
 Skin, contig. sides, 3d, 4th, 5th toes. 
 
 [ Skin, inner side of foot and ankle. 
 Internal Br. -j Skin, contig. sides, ad and 3d toes 
 [ and inner side of great toe. 
 
268 
 
 HUMAN ANATOMY 
 
 Begins in 
 the 
 
 1 Ganglio 
 / of Ribes 
 
 External 
 
 
 Sup. 
 
 Branches 
 
 
 Brs. 
 
 to join the 
 
 
 
 ist, 2d, 
 
 Superior 
 
 
 3d, 4th 
 
 Cervical 
 
 Anter 
 
 Cervical 
 
 Ganglion. 
 
 
 Nerves. 
 
 
 
 THE SYMPATHETIC SYSTEM 
 
 n f on the Anterior Communicating artery, at the base of 
 es. \ the brain. 
 
 [ Some to Pneumogastric, Glossopharyngeal, and 
 Hypoglossal Nerves. 
 
 (Ext. Br. forms Carotid Plexus. 
 Int. Br. forms Cavernous Plex. 
 along Int. Carotid Artery. 
 Anterior Branches, to Plexus on Ext. Carotid Artery. 
 
 f Pharyngeal, to Pharyngeal Plexus. 
 
 Int. I Superior Cardiac Nerve, to Cardiac Plexus; goes 
 Brs. I to Deep PI. on right side, to Superficial PI. 
 [ left side of body. 
 
 Ext. Brs. to f Middle 
 
 5th and 6th j Cervical 
 
 Cerv. N. [ Ganglion. 
 
 Ext. Brs. to f Inferior 
 
 7th and 8th X Cervical 
 
 Cerv. N. [ Ganglion. 
 
 Int. 
 Brs. 
 
 (Filaments along Inf. Thyroid Art. to Thyroid 
 
 j body and Larynx. 
 
 [ M id. Cardiac Nerve, to Deep Cardiac Plexus. 
 
 Int. ( Filaments along Vertebral Art. to cranium. 
 Brs. \ Inf. Cardiac Nerve, to Deep Cardiac Plexus. 
 
 Ext. Brs. to 
 Thoracic 
 
 N. 
 
 f " 1 
 j Thoracic j- 
 
 [ Ganglia. J 
 
 Int. 
 Brs. 
 
 Upper 5 or 6 to Aorta and Vertebral column. 
 
 3d and 4th to Post. Pulmonary Plexus. 
 
 Lower 6 form the 3 Splanchnic Nerves, thus 
 
 6-10, Great Splanchnic, to Semi-lunar Gang. 
 10, ii. Lesser Splanchnic, to Cceliac Plexus. 
 
 12, Smaller Splanchnic, to Renal and Solar 
 
 Plexuses. 
 
 Ext. Brs. to 
 Lumbar N. 
 
 4 
 
 Lumbar 
 Ganglia. 
 
 lnt. 1 Some to Aortic Plexus. 
 Brs. \ Some to Hypogastric Plexus. 
 
 Ext. Brs. to 
 Sacral N. 
 
 4 or 5 
 
 Sacral 
 
 Ganglia. 
 
 Int 
 Brs 
 
 '. f to Pelvic Plexus. 
 
 rs. \ to Plexus on Middle Sacral Artery. 
 
 {Coccygeal ) 
 G., or I In which ends the double chain of gangliated cords 
 Ganglion j enumerated above, and called THE SYMPATHETIC NERVE. 
 Impar. . 
 
 [FOR THE VARIOUS CONNECTED GANGLIA, ETC., SEE PAGES 223 TO 22?.] 
 
THE SYMPATHETIC 
 SYSTEM OF NERVES 
 
 Plate 16 
 
 tcG.ofRootofPncu 
 toftlrvas G. 
 Glasso-pha 
 
 from &Cervica 
 
 2 
 
 G^GANGLIOTJ 
 
 umogastric 
 toflypoylos&al N. 
 
 br. cfxt. Carotid A . 
 
 toPharyntjeal P. 
 to Inf. 'Thyroid 4* 
 
 Cardiac bT.Jr.PneumogastTic f?= PLEXUS . 
 and Rec. Larynyeal "Nerves AJ=ARTERY. 
 
 "Cardiac Fiexns 
 
 Mexua 
 
 duodenal 
 
 /. Sup. HemorrhoidaL P. 
 2.Spcrmatic Plexus 
 
 rpoaa&tric Plexus 
 
 Pelvic or Inf. ' ffypcyra&tnc Plexn* 
 
 Oarujlumlmpar. ^ Twtr del. 
 26<) 
 
2 7 o 
 
 HUMAN ANATOMY 
 
 FIG. 81. 
 
 ORGANS OF SPECIAL SENSE 
 
 The Special Senses are those of touch, taste, smell, sight and hearing. 
 The Skin is the principal seat of the sense of touch, the Tongue is the organ 
 of taste, the Nose is the peripheral organ of smell, the Eye of sight and the 
 Ear of hearing. 
 
 THE SKIN AND ITS APPENDAGES 
 
 The Skin consists of the Epidermis or Cuticle, the scarf-skin, com- 
 posed of 3 superficial and 2 deep layers; and the Derma, Corium, or Cutis 
 Vera, the true skin, composed of a 
 papillary layer above and a reticular 
 layer below. 
 
 The Epidermis, Cuticle or Scarf- 
 skin, is an unorganized epithelial 
 structure, having neither vessels nor 
 nerves. Its constituent epithelial 
 cells are agglutinated together in a 
 laminated arrangement, are flat and 
 dry on the surface, round and softer 
 in the central portion, columnar and 
 softest in the deepest layers. They 
 are arranged in the following layers, 
 from above downward, viz. 
 
 Stratum Corneum (i), horny epi- 
 thelial cells, without nuclei. 
 Stratum Lucidum, closely packed, 
 
 scaly cells. 
 
 Stratum Granulosum, flat, spin- 
 dle-shaped cells, containing 
 granules of eleidin, an interme- 
 diate substance in the forma- 
 tion of horn. 
 
 Rete Mucosum or Stratum Mal- 
 pighii (2), contains pigment 
 cells. 
 
 Basilar Layer or Stratum Germinativum, composed of columnar 
 
 epithelial cells placed perpendicularly on the surface of the derma, and 
 
 separated from the papillae by a homogeneous basement membrane. 
 
 The Derma, Corium or Cutis Vera (4), the true skin, is a highly organized, 
 
 tough yet elastic tissue, and serves to protect the parts beneath, to perform 
 
APPENDAGES OF THE SKIN 271 
 
 the functions of excretion and absorption, and as the chief seat of the sense 
 of touch. It consists of felted connective tissue, elastic fibres, blood- 
 vessels, lymphatics, and nerves; also unstriped muscular fibres in various 
 situations. It is formed in two layers, as follows: 
 Papillary Layer (3), situated next to the epidermis, is covered with 
 minute conical elevations (papillae), H^oo inch high, ^50 inch in 
 diameter at their base, very numerous and arranged in parallel 
 curved lines wherever sensibility is greatest. Each papilla contains 
 a capillary loop or plexus, the termination of one or more sensory 
 nerves, and in highly sensitive parts, an oval-shaped body, the 
 Tactile Corpuscle, a special sensory nerve ending. 
 
 Reticular Layer, the deep layer, is composed chiefly of interlacing bun- 
 dles of white fibrous tissue, in which are mingled some yellow elastic 
 fibres; also plain muscular fibres wherever hairs are found, and lym- 
 phatic vessels, blood-vessels, and nerves in plexiform arrangement. 
 Below this the elements of the skin become blended with the sub- 
 cutaneous tela or areolar tissue (5), which contains fat, except in a few 
 situations. 
 
 Mucous Membrane is a soft, velvety structure, analogous to the skin, 
 and found as the lining of the gastro-intestinal, pulmonary and genito- 
 urinary tracts. It is composed of Epithelium of various forms, in- 
 cluding the squamous, columnar, and ciliated, often arranged in several 
 layers; and Corium, analogous to the derma of the skin, consists of con- 
 nective tissue, blood-vessels, lymphatics, nerves, and unstriped muscle 
 cells; and is separated from the epithelium by a transparent basement 
 membrane. The mucous membrane has numerous glands embedded in 
 it, which secrete mucus to cover the surface for its protection from foreign 
 substances. Projecting from it in certain parts are villi and papilla. 
 processes which are analogous to the papillae of the skin. 
 
 Structures lying in the Skin, and directly beneath it, include the follow- 
 ing, viz. 
 
 Sensitive Papilla, containing Tactile Corpuscles in very sensitive parts, 
 
 in the papillary layer of the derma. 
 Hair Follicles, in the reticular layer of the derma, perforating the 
 
 derma and the epidermis: sometimes extending into the subcutaneous 
 
 tissue. 
 Sebaceous Glands (6), in the reticular layer of the derma; their ducts 
 
 (8, 9) opening usually into the hair-follicles, but occasionally on the 
 
 surface of the epidermis. 
 Sudoriferous or Sweat Glands, usually in the subcutaneous areolar 
 
272 
 
 HUMAN ANATOMY 
 
 FIG. 82. 
 
 tissue; their ducts perforating the derma and epidermis, to open on 
 the surface of the latter. 
 
 Fat Cells, in the subcutaneous areolar tissue. 
 Organs of Touch are the various sensory nerve- 
 endings in the skin or its vicinity and in mucous 
 membranes. They include minute, primitive 
 fibrilla or networks thereof, and certain special 
 terminal organs, as follows: 
 
 End-bulbs of Krause, minute bodies, Moo 
 inch in diameter, consisting of a capsule 
 surrounding a soft core, in which the axis- 
 cylinder of the nerve terminates, in a bulbous 
 expansion or in a coiled plexiform mass. 
 They are found chiefly in mucous mem- 
 branes, the genital organs, and the synovia] 
 membranes of the finger-joints. 
 Tactile Corpuscles, are oval bodies, ^oo inch 
 long, formed of connective tissue, and con- 
 sisting of a capsule and imperfect septa, which penetrate the interior. 
 The axis-cylinders of the nerve fibres (N) terminate within the 
 corpuscle in a globular enlargement. They are found in papillae of 
 the derma of the hand, foot, forearm, lips, 
 nipple, etc. Other tactile corpuscles, in 
 the papillae of parts devoid of hair, consist 
 of a capsule, containing two or more 
 granular cells, between which the nerve- 
 fibre is supposed to terminate. 
 Pacinian Corpuscles, are composed of 
 lamellae (d), consisting of connective 
 tissue fibres, arranged concentrically 
 around a central clear space (ni), in which 
 the nerve-fibre (n) terminates at the distal 
 extremity in a rounded end (a), which is 
 often bifid or even trifid. They are found 
 chiefly on the nerves of the palm of the 
 hand and the sole of the foot, the ends of 
 the fingers, and the genital organs, lying 
 in the subcutaneous tissue. 
 
 APPENDAGES or THE SKIN 
 
 The Nails (Ungues) are curved, horny structures, a modification of the 
 epidermis, molded upon the derma at the dorsal surface of the terminal 
 
 FIG. 83. 
 
THE TONGUE 273 
 
 phalanges of the fingers and toes. Each nail is convex on its outward 
 surface, and is embedded by its Root (radix unguis) into a fold of the skin. 
 Its 
 
 Matrix, is that portion of the derma directly beneath the nail. It is 
 
 covered with highly vascular papillae. The 
 
 Lunula, is a white crescentic portion of the nail nearest to its root, 
 
 produced by the diminution in number and size of the papillae beneath. 
 
 The Hairs (Pili) are also a modified form of the epidermis, found over 
 
 nearly the whole surface of the body, much varied in size and color. Each 
 
 hair consists of a Root and a Shaft. The 
 
 Root (radix pili), is lodged in an involution of the epidermis called the 
 Hair-follicle, which sometimes extends into the subcutaneous cellular 
 tissue. The root rests on a vascular papilla, at the bottom or Bulb 
 of the follicle, which supplies it with material for its growth. 
 Shaft (scapus pili), is the projecting portion of the hair. It consists 
 of a medulla in the centre, next a fibrous portion, externally a cortex 
 of thin, flat scales. The finest hairs have no medulla. 
 Point (apex pili), consists of the fibrous portion and the cortex, the 
 
 medulla being wanting. 
 
 Sebaceous Glands (Glandulae Sebaceae) are small, glandular bodies 
 situated in the corium over most of the body, but not in that of the palmar 
 surface of the hands nor on the plantar surface of the feet. Each gland 
 consists of a single sacculated duct, usually opening into a hair-follicle, 
 but sometimes ending on the surface of the epidermis. They are most 
 abundant in the scalp, the face, around the anus, and the apertures of the 
 nose, mouth and external ear. The largest are the 
 Meibomian Glands, situated in the eyelids. 
 
 Sudoriferous or Sweat Glands (Glandulae Sudoriferae) consist each of a 
 single convoluted tube, situated usually in the subcutaneous cellular 
 tissue, and opening on the surface of the integument by a spiral duct 
 which pierces the derma and the epidermis. The duct has two coats, an 
 external fibro-cellular, which is continuous with the corium, and an 
 epithelial lining, continuous with the epidermis. These glands are 
 estimated as varying, in different parts of the integument, from 417 to 
 2800 to the square inch, giving for the whole body a total number of nearly 
 two millions and a half, representing an evaporating surface of about 8 
 square inches. They are most numerous on the palm of the hand. 
 
 THE TONGUE (LINGUA) 
 
 The Tongue is the organ of taste. It is composed of siriated muscle, 
 is covered with mucous membrane, and is supplied with blood-vessels, 
 18 
 
274 
 
 HUMAN ANATOMY 
 
 lymphatics and nerves. Its base (radix linguae) is connected with the 
 hyoid bone by the hyo-glossi and genio-hyo-glossi (mm. genioglossi) 
 muscles and the hyo-glossal membrane; with the epiglottis, by the 3 
 gJosso-epiglottic folds of mucous membrane; with the soft palate, by the 
 anterior pillars (arci glosso-palatini) of the fauces; and with the pharynx, 
 by the superior constrictor muscles and the mucous membrane. Its tip 
 (apex linguae), thin and narrow, is free in the mouth, and rests when 
 quiet against the lower incisor teeth. Its wider surface (facies inferior 
 linguae) is connected with the lower jaw by PIG 
 
 the genio-hyo-glossi (mm. genioglossi) mus- 
 cles. Its mucous covering is reflected later- 
 ally on the inner surface of the gums, form- 
 ing in front the frjEnum lingua (frenulum lin- 
 guae), a vertical fold below the tip. The 
 tongue presents the 
 
 Raphe (sulcus medianus linguae), a ver- 
 tical, fibrous septum, in the median line, 
 dividing the tongue into two symmet- 
 rical halves, and terminating behind in a 
 depression, the foramen ctzcum, about an 
 inch from the base of the organ. 
 Papillcs V dilates (i) (circumvallate), 8 to 12 
 in number, in two rows on the dorsum of 
 the tongue, the rows forming a V and 
 meeting in front of the foramen cacum. 
 Papilla Fungiformes (2) (lenticular), 
 scattered irregularly over the dorsum, 
 chiefly at its sides and apex. 
 Papilla Filiformes (conical), cover the anterior two- thirds of the 
 dorsum and' have numerous filiform processes or secondary papillae 
 projecting from their apices. 
 
 Taste-buds, flask-shaped bodies, found in the epidermis of the circum- 
 vallate papillae, and in some of the fungifqrm (described below). 
 Glands of Blandin or Nuhn, mucous glands, one on either side of the 
 fraenum, having 4 to 6 ducts which open on the under surface of the 
 apex. 
 Racemose Serous Glands of Ebner, at the back of the tongue, their ducts 
 
 opening into the fossae of the vallate papillae. 
 Hyo-glossal Membrane, a strong, fibrous lamina, connecting the under 
 
 surface of the base of the tongue to the bod> of the hyoid bone. 
 Extrinsic Muscles of the Tongue, are the stylo-, hyo-, chondro-, genio- 
 
THE TONGUE 275 
 
 hyo-, palato-glossi muscles, and part of the superior constrictors of 
 the pharynx (pharyngeo-glossi). These have been described on 
 page 82. 
 
 Intrinsic Muscles of the Tongue, are the various fibres of the lingualis 
 muscle, superior, inferior, transverse and vertical. (See page 83.) 
 Taste-buds are flask-shaped bodies, situated in the epidermis (e) of the 
 vallate and some of the fungiform papillae; also found at the sides of the 
 base of the tongue, on the epiglottis and the soft palate. Each bud has a 
 broad base, which rests on the corium, and a neck opening on the mucous 
 surface by an orifice, the gustatory pore (0). The buds are formed by sup- 
 porting cells, mostly arranged like the staves of a 
 cask; and spindle-shaped, nucleated gustatory cells 
 in the central portion, each terminating at the 
 gustatory pore in a fine filament, the gustatory 
 hair. Terminal nerve-fibrils ramify between the 
 gustatory cells, and others are found between the 
 cortical cells. 
 
 Vessels of the Tongue. The Arteries are de- 
 rived from the lingual, facial, and ascending 
 pharyngeal, branches of the external carotid. 
 The^ Veins open into the internal jugular. The 
 Lymphatics of the posterior half of the tongue 
 pass to one or two small glands on the hyo-glossus 
 muscle, and thence to the deep glands of the neck; 
 
 those of the anterior half are connected with the sub-mandibular 
 lymphatics. 
 
 Nerves of the Tongue are as follows: the 
 
 Lingual Branch of the Mandibular Division of the $th, to the papillae of the 
 fore part and sides of the tongue, endowing the anterior two-thirds of the 
 organ with ordinary sensibility. 
 
 Chorda Tympani is the continuation of the glosso-palatine nerve (n. inter- 
 medius) or "pars intermedia, " the sensory root of the facial, it runs in 
 the sheath of the lingual nerve and is distributed to the same region, 
 being the nerve of taste for the anterior two-thirds of the tongue. 
 
 Lingual Branches of the gth or Glosso- pharyngeal, to the mucous membrane 
 of the base and sides and the circumvallate papillae, being the nerves of 
 taste and ordinary sensation for the posterior third of the tongue. 
 
 Hypo-glossal or j 2th Nerve, the motor nerve of the tongue, distributed to 
 the intrinsic and extrinsic muscles, 
 
276 HUMAN ANATOMY 
 
 Superior Laryngeal Branch of the loth or Vagus, sends a few filaments, by 
 way of its internal laryngeal branch, to the root of the tongue. 
 
 Sympathetic Filaments, from the nervi molles on the lingual and other 
 arteries supplying the organ (Spitzka). 
 
 Special Nerves of Taste in the Tongue, are the- 
 Chorda Tympani, the continuation of the sensory root (glosso-palatine 
 
 nerve or n. inter medius) of the Facial, for its anterior two- thirds; 
 
 perceiving saline, acid and styptic qualities (Flint). 
 Lingual Branches of the Glosso-pharyngeal, for its posterior third; appre- 
 ciating alkaline, metallic, sweet and bitter tastes (Flint). 
 
 Sapolini's view of the Chorda Tympani Nerve. From repeated dis- 
 sections, Dr. Sapolini, of Milan, believes the chorda tympani to be a 
 separate cranial nerve, a continuation of the pars intermedia of Wrisberg 
 (glosso-palatine nerve or n. intermedius) which has its deep origin in the 
 upper end of the nucleus of the glosso-pharyngeal nerve in the floor of 
 the 4th ventricle and the solitary or "trineural" tract in the medulla, 
 joins the facial in the internal auditory meatus, and terminates in a dense 
 plexus with the lingual branch of the th in the muscular substance of the 
 tongue. He further concludes that the chorda tympani is the nerve 
 governing the movements of the tongue in speech, and that the nerves of 
 taste are the Lingual Branches of the 5th and gth nerves. 
 
 THE NOSE (NASUS) 
 
 The Nose is the peripheral organ of smell, and consists of the outer nose 
 (nasus externus) and the nasal fossae (cavum nasi). The Outer Nose 
 projects from the centre of the face, and is composed of a framework 
 of bones and cartilages, covered by skin, lined by mucous membrane, and 
 supplied with vessels and nerves. At its base it presents two elliptical 
 orifices, the nostrils or anterior nares, separated by a septum, the columna 
 (septum mobile nasi), and guarded at their margins by numerous stiff 
 hairs, the mbrissoe. The 
 
 Bony Framework, is formed by the nasal bones and the nasal processes 
 of the maxillae (see page 27). 
 
 Cartilages (cartilagines nasi) are 5, two upper lateral (cartilago nasi 
 latralis), two lower lateral (cartilago alaris nasi major), and the 
 cartilage of the septum (cartilago septi nasi), connected together and 
 to the bones by a tough, fibrous membrane, which permits of free 
 movement between them. 
 Septum Nasi, the nasal septum, is formed anteriorly by the cartilage 
 
THE NOSE 
 
 277 
 
 of the septum, posteriorly by the perpendicular plate of the ethmoid 
 bone above and the vomer below. 
 
 The Nasal Fossae (cavum nasi) are two irregular cavities in the middle 
 of the face, separated by the septum nasi, opening in front by the anterior 
 nares, behind by the posterior nares (choanae) into the naso-pharynx. 
 Their osteological description has been given on page 37. Each fossa is 
 divided into an olfactory portion (regio olfactoria), containing the upper 
 part of the septum and the superior turbinal process and a respiratory 
 portion (regio respiratoria), comprising the rest of the fossa. It is 
 further divided, from above downward, into the superior, middle and 
 
 16 H 12 
 
 inferior meatuses of the nose, which are separated from each other by the 
 middle (concha nasalis media) (2) and inferior turbinal (concha nasalis 
 inferior) bones. Each fossa presents the 
 
 Vestibule (9), a slight dilatation inside the aperture of the nostril, 
 extending as a small pouch, the ventricle, toward the point of the nose. 
 Spheno-ethmoidal Recess, on the outer wall, above the superior tur- 
 binal process into which the sphenoidal sinus (4) opens. 
 Bulla Ethmoidalis, an elevation on the outer wall of the middle meatus, 
 
 on or above which are the orifices of the middle ethmoidal cells. 
 Hiatus Semilunaris, a narrow groove in the outer wall, in front of 
 the bulla ethmoidalis, into which open the anterior ethmoidal cells 
 and the antrum (sinus maxillaris) of Highmore (i) . 
 Infundibulum (3), the superior prolongation of the middle meatus, 
 
278 HUMAN ANATOMY 
 
 leading into anterior ethmoidal cells and the frontal sinus (see 
 page 38). 
 Atrium (atrium meatus medii nasi) (5), a depressed area above the 
 
 vestibule, forming the anterior extremity of the middle meatus. 
 Orifice of the Nasal Duct (ductus naso-lacrimalis) (7), on the outer wall, 
 
 in the anterior part of the inferior meatus. 
 
 Naso-palatine Recess, a depression at the lower edge of the cartilage of 
 
 the septum; near it a minute orifice leads into a blind pouch, the 
 
 rudimentary organ of Jacobson (organon vomero-nasale). 
 
 The Schneiderian or Pituitary Membrane is the mucous membrane 
 
 lining the nasal fossae, thick and vascular over the septum and the 
 
 turbinal processes, but very thin elsewhere. On it, in the upper portion of 
 
 the fossae, are distributed the terminal filaments of the olfactory nerve, the 
 
 FIG. 87. 
 
 special nerve of the sense of smell. It is continuous with the mucous lin- 
 ing of the pharynx, Eustachian tube (tuba auditiva), tympanum and 
 mastoid cells; also with that of the frontal, ethmoidal and sphenoidal 
 sinuses, the maxillary antrum, nasal duct, and the conjunctiva. It is 
 covered with columnar epithelium, which is ciliated throughout most of 
 its extent, contains much adenoid tissue, is provided with mucous and 
 serous glands, and in the olfactory region it contains the 
 
 Olfactory Cells of Schultze, spindle-shaped, epithelial cells, grouped 
 around and between the columnar cells of the epithelium, having at 
 
THE NOSE 279 
 
 one end hair-like processes, the olfactory hairs, and joined together by 
 
 other processes, forming an intricate plexus on which the terminal 
 
 fibres of the olfactory nerves are supposed to end. 
 Glands of Bowman, are tubular, often branched, serous glands, in a 
 
 layer beneath the epithelium, extending through the thickness of the 
 
 mucous membrane, in the olfactory region. 
 
 Nerves supplying the Outer Nose are branches from the facial nerve 
 to the muscles; branches from the infraorbital and infratrochlear, and the 
 nasal branch of the ophthalmic, supplying the integument. Those 
 supplying the Nasal Fossa are the 
 
 Olfactory or ist Nerve (a), over the upper third of the septum (i), the 
 
 superior turbinal process and the surface of the ethmoid in front of it. 
 Nasal Branch of the Ophthalmic (d}, to the septum and outer walls. 
 Anterior Dental or Alveolar Branch of the Maxillary, to the inferior 
 
 meatus of the nose and the inferior turbinal bone. 
 Vidian Nerve (n. canalis pterygoidei), to the septum and the inferior 
 
 turbinal bone. 
 Naso-palatine (e), from the spheno-palatine ganglion, to the middle of 
 
 the septum; thence through the anterior palatine foramen (/). 
 Anterior Palatine (h), from the spheno-palatine ganglion, to the middle 
 
 and lower turbinal bones, by its inferior nasal branches. 
 Superior Nasal Branches, from the spheno-palatine ganglion, to the 
 
 septum and the superior and middle turbinal bones. 
 
 Arteries of the Nose. The arteries supplying the Outer Nose are 
 the lateralis nasi branch of the facial (a. maxillaris externa); the inferior 
 artery of the septum, from the superior coronary branch of the facial 
 (a. maxillaris externa); and the nasal branch of the ophthalmic and the 
 infraorbital, which go to the dorsum and sides of the nose. The Arteries 
 of the Nasal Fosses form a close, plexiform network beneath and in the 
 mucous membrane, and are the 
 
 Ant. and Post. Ethmoidal, from the ophthalmic, to the roof. 
 Spheno-palatine, branch of the internal maxillary, to the mucous mem- 
 brane over the turbinal bones, the meatuses, and the septum. 
 Infraorbital and Alveolar, branches of the internal maxillary, to the 
 
 mucous lining of the antrum. 
 
 Inferior Artery of the Septum, from the superior coronary branch of the 
 facial (a. maxillaris externa), to the mucous membrane of the 
 
 septum. 
 
 . 
 Veins of the Nose. Those of the outer nose terminate in the facial and 
 
 ophthalmic veins. Those of the nasal fossa form a close, cavernous-like 
 
280 
 
 HUMAN ANATOMY 
 
 network beneath the mucous membrane, and terminate in the facial and 
 ophthalmic veins, a few going to the veins in the interior of the skull. 
 
 THE EYE 
 
 [For an osteological description of the Orbit, see page 35.] 
 
 The Eyeball (bulbus oculi) is situated in the anterior part of the orbital 
 
 cavity, on a cushion of connective tissue and fat, where it is retained by 
 
 its muscles, the optic nerve, the conjunctiva, etc., and protected in front 
 
 by the eyelids and eyebrows. It is composed of segments of two spheres 
 
 of different sizes; the anterior segment being the smaller, forming about 
 
 Y of the eyeball, and named the cornea; the posterior and larger 
 
 segment, is formed by the sclerotic coat 
 
 (tunica fibrosa oculi), and constitutes 
 
 the remaining % of the globe. It is 
 
 surrounded by a thin, membranous sac, 
 
 the capsule (fascia bulbi oculi) of Tenon, 
 
 and has the following '< 
 
 Diameters, in the adult, antero-pos- 
 
 terior and transverse, nearly an 
 
 inch, vertical about %o of an inch. 
 
 Anterior Pole, the central point of 
 
 the anterior curvature. 
 Posterior Pole, the central point of 
 
 the posterior curvature. 
 Sagittal Axis (axis optica), a line 
 
 joining the two poles. 
 The Capsule of Tenon (fascia bulbi 
 oculi) (3) is a thin membrane which en- 
 velops the eyeball from the optic nerve 
 to the ciliary region, where it blends with the ocular conjunctiva. Its 
 smooth, inner surface is in contact with the outer surface of the scler- 
 otic coat (tunica fibrosa oculi), with which it is connected by delicate 
 bands of connective tissue. Posteriorly it is continuous with the sheath 
 (17) of the optic nerve, and from it tubular sheaths are prolonged over 
 the muscles which move the eyeball, giving off slips to the bones of the 
 orbit. The 
 
 Check Ligaments, internal and external, are expansions from the 
 sheaths of the internal and external recti muscles, and are attached 
 to the lacrimal and malar bones respectively. 
 
THE EYE 28l 
 
 Suspensory Ligament of the Eye (Lock wood's), is a thickening of the 
 
 lower part of the capsule, slung like a hammock below the eyeball, 
 
 and attached to the lacrimal and malar bones. 
 Peri-sclerotic Lymph-space, intervenes between the capsule and the 
 
 sclerotic, and is continuous with the subdural and subarachnoid 
 
 spaces. 
 
 Tunics of the Eyeball are 3 in number, named from without inward as 
 follows: the 
 ; Sclerotic (fibrosa) (3) and Coronea (i), the external, fibrous, and 
 
 protective tunic. 
 Choroid (choroidea) (4), Ciliary Body (corpus ciliare) (5), and Iris (8), 
 
 the vascular tunic, sometimes called the Uveal Tract. 
 Retina (tunica interna) (13), the innermost, nervous tunic. 
 
 Refracting Media are 3 in number, and are named as follows: the 
 Aqueous Humor (humor aqueus) (2), ^fills the anterior (2) and posterior 
 
 (9) chambers (camerae). 
 
 Vitreous Body (corpus vitreum) (18), fills the concavity of the retina. 
 Crystalline Lens (lens crystallina) (15), in front of the vitreous body. 
 
 THE SCLEROTIC AND CORNEA 
 
 The Sclerotic, or hard coat (tunica fibrosa oculi), is the posterior five- 
 sixths of the jjx.trnal iunic of the eyeball, the anterior one-sixth being the 
 Cornea. Externally it is of a whita-color, covered anteriorly by the 
 conjunctival mucous membrane, posteriorly being continuous with the 
 fibrous sheath of the optic nerve. Internally its color is brown, and its 
 surface marked by grooves for the ciliary nerves. The optic nerve pierces 
 it posteriorly, also the long and short ciliary arteries, posterior ciliary 
 veins and short ciliary nerves. In the equatorial region it is pierced 
 obliquely by the venae vorticosae, and around the corneal border by the 
 anterior ciliary arteries and veins. It is composed of white fibrous tissue, 
 intermixed with elastic fibres, and of flattened connective-tissue corpuscles, 
 some of which are pigmented. The Sclerotic presents for consideration 
 the following points: 
 
 Thickness, ^5 inch posteriorly, %o inch anteriorly. 
 
 Lamina Fusca, a layer of very fine pigmented connective tissue, con- 
 necting the sclerotic with the outer surface of the choroid. 
 
 Lamina Cribrosa (lamina cribrosa sclerae), the posterior perforated 
 portion of the sclerotic, which at this point is a thin, cribriform 
 lamina. Its largest opening transmits the arteria centralis retinae. 
 
282 HUMAN ANATOMY 
 
 Arteries, from the ciliary, are few and in a coarse network, the 
 
 capillaries uniting at long and wide intervals. 
 Nerves, from the ciliary, their mode of ending unknown. 
 
 The Cornea, or horny body, is the anterior transparent projecting 
 portion of the external tunic of the eyeball, forming about one-sixth 
 thereof. It is set into the sclerotic as a watch-crystal into its case, is of 
 nearly circular base, and its curvature varies in degree in different persons, 
 and in the same person at different ages, becoming flattened in advanced 
 life. It consists of 4 layers, centrally the true fibrous corneal tissue, 
 having in ^ront the conjunctival epithelium; behind, a homogeneous 
 elastic lamina and thyepithelial lining of the anterior chamber. The 
 Conjunctival Epithelium, consists of several layers of epithelial cells, 
 the deepest being columnar, the central polyhedral with processes 
 and the superficial scaly with flattened nuclei. 
 
 Jj Proper Corneal Substance, a transparent, firm, fibrous structure, con- 
 tinuous with the sclerotic, and composed of about 60 lamella of 
 modified connective tissue, superimposed one on the other, and 
 connected by a cement, in which are spaces of stellate shape, each 
 containing a cell, the corneal corpuscle. The anterior layer of the 
 corneal substance was called by Bowman the anterior elastic lamina. 
 Posterior Elastic Lamina, Membrane of Descemet, or Demours, is a 
 structureless basement membrane, of extreme thinness and trans- 
 parency, the latter being unaffected by water, alcohol or acids; very 
 brittle, exceedingly elastic, and curls up inwardly upon itself, when 
 detached from the true cornea. At the corneal margin it breaks up 
 into fibres, some of which are continuous with the ligamentum 
 pectinatum of the iris. 
 
 Fontana' s Spaces (spatia anguli iridis), are small, cavernous spaces 
 between the fibres which go to form the ligamentum pectinatum. 
 In some animals, as the ox, they form regular canals. They com- 
 municate with the anterior chamber and with the 
 
 X j Canal of Schlemm, or Sinus Venosus Sclerce, a minute canal at the 
 internal corneo-sclerotic junction, extending around the circumfer- 
 ence of the attached border of the iris. It. communicates with the 
 anterior chamber through the spaces of Fontana, also with the scleral 
 v veins. 
 
 Posterior Endothelial Layer (endothelium cameras anterioris), a single 
 layer of flattened, polygonal, transparent, nucleated cells, covers 
 the posterior surface of the elastic lamina, lines the anterior chamber 
 and the spaces of Fontana, and is reflected on to the front of the iris. 
 
THE EYE 283 
 
 Vessels, none, the capillary vessels terminating in loops at its circum- 
 ference, so that it is practically a non-vascular structure. 
 ^ j Nerves, are numerous; 24 to 36 twigs from the Ciliary nerves form an 
 intricate plexus throughout its laminated substance. 
 
 THE CHOROID, CILIARY BODY AND IRIS 
 
 The Middle Tunic (Tunica Vasculosa Oculi) of the Eye is formed from 
 behind forward by the Choroid, the Ciliary Body and the Iris; the former 
 being the vascular ami pigmented tunic; the latter a circular, muscular 
 curtain or septum, with the pupil, an opening in its centre; while the ciliary 
 body connects the choroid with the iris. 
 
 The Choroid is a thin, vascular membrane, of dark-brown or chocolate 
 color, which invests the posterior ^ of the globe, extending from the 
 optic nerve entrance behind to the ora serrata of the retina. It is loosely 
 connected externally by the lamina fusca to the sclerotic, the space be- 
 tween being the peri-choroidallymph-space, and is covered by a thin mem- 
 brane, the lamina superchoroidea, containing spaces between its constituent 
 lamellae. Internally it is connected with the pigmentary layer of the retina 
 by the lamina basalis or membrane of Bruch, a very thin, structureless 
 membrane. The Choroid terminates anteriorly in the ciliary processes 
 (see below), and is composed of 2 layers, as follows: 
 Lamina Vasculosa, the external layer, consists chiefly of the venae 
 vorticosae, the larger branches of the short ciliary arteries, and dark 
 pigment cells. 
 
 Lamina Chorio-capillaris or Tunica Ruyschiana, the internal layer, 
 consists of a very fine capillary plexus, formed by the short ciliary 
 vessels. 
 Tapelum, is the name applied to the iridescent appearance seen in the 
 
 outer and posterior part of the choroid of many animals. 
 Arteries, are the short ciliary and recurrent branches from the long 
 
 and anterior ciliary arteries. 
 Veins (2), unite into 4 or 5 trunks (4), which pass out through the 
 
 sclerotic near its equator. 
 Nerves (3), are derived from thej^d, $th and sympathetic, through the 
 
 long ciliary and the ciliary branches of the ophthalmic ganglion. 
 The Ciliary Body (corpus ciliare) (5), comprises the orbiculus ciliaris, 
 (annulus ciliaris), the ciliary processes, and the ciliary muscle. It con- 
 nects the choroid with the circumference of the iris. The 
 
 Orbiculus Ciliaris (annulus ciliaris), is a zone about ^ inch wide, 
 directly continuous with the anterior part of the choroid. 
 
284 HUMAN ANATOMY 
 
 Ciliary Processes, are 60 to 80 folds, formed by the plaiting of the 
 choroid and its lamina basalis at their anterior margin, and are 
 received into corresponding folds of the suspensory ligament of the 
 lens. They form a sort of plaited frill behind the iris, around the 
 margin of the lens, and are similar in structure to the choroid. 
 
 Ciliary Muscle or Muscle of Bowman (m. ciliaris) , is a ring of un- 
 striped muscular fibres on the outer surface of the anterior part of 
 the choroid, and consists of radiating (fibrae meridianales) and cir- 
 cular fibres (fibrae circulares). The former arise from the corneo- 
 sclerotic junction and pass backward to the choroid in front of the 
 
 PIG. 89. 
 
 Nerves 
 
 Sclera 
 
 retina. The circular fibres are internal to the radiating ones, have a 
 circular course around the attachment of the iris, and by drawing 
 on the ciliary processes they relax the suspensory ligament of the 
 lens, permitting the lens to become more convex by its own elasticity. 
 It is supplied by the 3d nerve. 
 
 The Iris (6) is a perforated contractile curtain, suspended in the aqueous 
 humor behind the cornea and in front of the lens, and is the anterior 
 portion of the middle tunic of the eyeball, being continuous with the 
 ciliary body and the choroid. It is about % inch wide, K o o inch thick, and 
 is composed of radiating and circular muscular fibres, a fibrous stroma and 
 pigment cells, covered by a layer of endothelial cells continuous with those 
 of the posterior elastic lamina of the cornea. The 
 
THE EYE 285 
 
 Pupil (pupilla), is the central opening in the iris, situated a little to 
 the nasal side of the centre, diameter >^2 to Y inch. 
 
 Ligamentum Pectinatum Iridis, or Dollinger's band, is the suspensory 
 ligament of the iris, connecting its ciliary margin with the posterior 
 elastic lamina of the cornea. 
 
 Pars Iridica Retina or Uvea, pigmented epithelium of deep purple 
 color, on the posterior surface of the iris. 
 
 Sphincter Pupillce, a layer of circular muscular fibres around the pupil- 
 lary margin, supplied by the 3d nerve. 
 
 Dilator Pupilla, radiating muscular fibres from the pupillary margin 
 toward the ciliary border, supplied by fibres of the sympathetic from 
 the ciliary ganglion. 
 
 Membrana Pupillaris, a vascular membrane which covers the pupil in 
 the foetus, disappearing about the eighth month, occasionally perma- 
 nent. 
 
 Arteries, are derived from the long and anterior ciliary, forming the 
 circulus major at the ciliary border, and the circulus minor near the 
 pupillary margin. 
 
 Veins, empty into those of the ciliary processes and the anterior 
 ciliary veins. 
 
 Nerves of the Iris, are derived from the 3d, 5th and the sympathetic, 
 through the long and short ciliary nerves. The 3d supplies the 
 circular fibres, the sympathetic the radiating ones, the 5th being 
 nerves of common sensation. 
 
 THE RETINA (TUNICA INTERNA) 
 
 The Retina, the innermost or nervous tunic of the eye, is a delicate, 
 grayish, transparent membrane, about ^75 of an inch thick at the fundus, 
 3^oo inch at the anterior margin. It is formed by a membranous ex- 
 pansion of the optic nerve elements, and extends from the termination of 
 that nerve nearly as far forward as the ciliary processes, terminating in a 
 jagged margin, the or a serrata, though its fibrous stroma is continued as 
 the pars ciliaris retina over the ciliary body. The Retina presents for 
 examination the following points: 
 
 Macula LiUea, or Yellow Spot, situated on the retina, exactly in the 
 visual axis; in an elevated oval spot where vision is very acute, the 
 retina being very thin and full of nerve elements closely packed 
 together at the expense of its connective tissue. No rods, no nerve- 
 fibre layer here, but the cones and ganglion-cells are very numerous. 
 Fovea Centralis, a depression at the centre of the macula lutea, M 25 
 to Ko inch in diameter, in which the sense of vision is most acute. 
 
286 HUMAN ANATOMY 
 
 Porus Opticus or Optic Disk, the point where the optic nerve enters, 
 lies about % inch internal to the yellow spot. It is often called the 
 blind spot, being the only part of the fundus from which the power of 
 vision is absent. 
 
 Cotticulus Nervi Optici or Optic Papilla, is a slight eminence of the 
 nervous substance at the porus opticus; the central artery of the 
 retina pierces its centre which is depressed slightly, forming the 
 Optic Cup (excavatio papillae nervi optici). 
 
 Pars Ciliaris Retina, is that portion of the retinal stroma which is 
 prolonged over the ciliary body, and continued over the back of the 
 iris as the pars iridica retina. It is destitute of nerve-elements. 
 
 Arteries of the Retina, arise from the arteria centralis retinas (branch 
 of the ophthalmic artery), just behind the porus opticus; run chiefly 
 upward and downward, accompanied by veins, to terminate in a 
 minute capillary plexus. They do not anastomose with each other, 
 being terminal arteries. No vessels exist in the fovea centralis, and 
 only the finest capillaries in the macula lutea. 
 
 Structure of the Retina. The retina is composed of nervous elements, 
 blood-vessels, pigmented epithelium, and modified connective tissue re- 
 sembling the neuroglia of the brain; the latter being called the radiating 
 fibres or fibres of Mutter, which form the two limiting membranes and 
 stretch between them, passing through all the nervous layers except 
 Jacob's membrane. The structures are arranged in 10 layers, as follows: 
 
 Membrana Limitans Interna, derived from the supporting frame-work 
 and shown in the cut by the lowest line. 
 
 Layer of Nerve-fibres (stratum opticum) (i), formed by the expansion 
 of the optic nerve, the fibres of which, as simple axis-cylinders, pass 
 through all the succeeding layers of the retina. 
 
 Ganglionic Layer (2), a single layer of large ganglion-cells, which give 
 off their axons into the preceding layer and their dendrites into the 
 inner molecular layer. 
 
 Inner Plexiform Layer (3), is made up of a dense reticulum of minute 
 fibrils, formed by the interlacement of the dendrites of the ganglion- 
 cells with those of the cells of the next layer. 
 
 Inner Nuclear or Granular Layer (4), consists of closely packed cells of 
 3 kinds, bipolar, amacrine, and cells connected with the fibres of 
 Miiller. 
 
 Outer Plexiform Layer (5), a dense network of minute fibrils derived 
 from the processes of the cells in the adjoining layers. 
 
 Outer Nuclear or Granular Layer (6), contains several strata of oval 
 nuclear bodies, named rod-granules and cone granules, which are 
 
THE EYE 
 
 287 
 
 FIG. 90. 
 
 respectively continuous with the rods and cones of Jacob's membrane. 
 Membrana Limitans Externa, derived from the supporting frame- 
 work of the retina, is shown in the cut by a horizontal line between 
 layers 6 and 7. 
 
 Jacob's Membrane, or Layer of Rods and Cones (7), the perceptive 
 
 portion of the retina, is composed of a 
 palisade-like arrangement of rods and 
 cones, the terminal organs probably 
 of the optic nerve fibres. 
 Pigmentary Layer, or Tapetum Nigrum 
 (8), formerly described as a part of 
 the choroid, consists of a single layer 
 of hexagonal epithelial cells, loaded 
 with pigment-granules. It extends 
 with the retinal stroma as the pars 
 ciliaris retina, (see page 285), beyond 
 the ora serrata, where the nervous 
 layers terminate. 
 
 REFRACTING MEDIA 
 
 The Aqueous Humor (humor aqueus) is 
 a clear, alkaline, serous fluid, composed of 
 water 96.7, albumen o.i, chloride of sodium 
 and extractive matters 3.2, weighing 4 to 5 
 grains, and filling the anterior (camera oculi 
 anterior) and posterior aqueous chambers 
 (camera oculi posterior) which communicate 
 with each other when the pupil is dilated 
 sufficiently to remove the pupillary margin 
 of the iris from the surface of the lens. 
 The 
 
 Anterior Chamber (camera oculi anterior) 
 of the Eyeball, has the cornea in front 
 and the iris behind. The peripheral 
 angle of this chamber is called the Fil- 
 tration Angle (angulus iridis). 
 Posterior Chamber (camera oculi posterior) of the Eyeball, is a narrow 
 chink between the peripheral part of the iris, the suspensory ligament 
 of the lens, and the ciliary processes. 
 
 The Vitreous Body (corpus vitreum) is a transparent jelly-like sub- 
 stance, composed of an albuminous fluid enclosed in a delicate membrane, 
 
288 HUMAN ANATOMY 
 
 also transparent and named the hyaloid membrane (membrana hyaloidea). 
 It is apparently structureless, has neither vessels nor nerves, and is situated 
 in the concavity of the retina, which it fills, forming about Y of the entire 
 globe. Running antero-posteriorly in its centre is a canal, filled with fluid, 
 and lined by a prolongation of the hyaloid membrane, called the 
 
 Canal of Stilling (canalis hyaloideus), which in the foetus conveyed the 
 
 hyaloid artery to the membrana pupillaris. It extends from the 
 
 entrance of the optic nerve, forwards directly through the centre 
 
 of the vitreous humor to the back of the crystalline lens. 
 
 Fossa Patellaris, is a deep concavity on the front of the vitreous, for 
 
 the posterior convex surface of the lens. 
 
 Hyaloid Membrane, is the delicate capsule which encloses the vitreous 
 humor, and has been supposed to give off delicate septa into its sub- 
 stance. In front of the ora serrata it is thickened and is termed the 
 Zonula Ciliaris or Zonule of Zinn, presents a series of furrows, radially 
 arranged, for the reception of the ciliary processes. It splits into 2 
 layers, one of which lines the fossa patellaris, the other is the 
 Suspensory Ligament of the Lens, passes over the ciliary body to be 
 
 attached to the capsule of the lens. 
 
 Canal of Petit (spatia zonularia), a sacculated canal, behind the 
 suspensory ligament, encircles the equator of the lens, and lies 
 between the two layers into which the zonule of Zinn is split. 
 The Crystalline Lens (lens crystallina) is a bi-convex, elastic, trans- 
 parent body, enclosed in a capsule, held in place by a suspensory ligament, 
 and situated immediately behind the pupil 
 and in front of the vitreous body, in the fossa 
 patellaris of which its posterior and most con- 
 vex surface rests. The ciliary processes en- 
 circle it and slightly overlap its margin. It 
 consists of concentric layers formed of minute 
 parallel fibres, which are hexagonal prisms with 
 dentated edges fitting accurately into each 
 other. Faint lines, six or more in number, 
 radiate from the anterior and posterior poles 
 
 to the circumference and correspond to the free edges of septa in the 
 lens. The external layers are soft, the deeper are firmer, and the central 
 ones form a hard nucleus, the nucleus lentis. The lens is unorganized, 
 having neither vessels nor nerves, but is nourished by imbibition from 
 neighboring structures, possibly from the aqueous humor. Its 
 
 Capsule (capsula lentis), is transparent, elastic, iHjooo i ncn thick 
 antreiorly, Hooo inch posteriorly; has a layer of flat cells between its 
 
THE EYE 289 
 
 anterior portion and the lens, which, after death, break down into a 
 fluid, the liquor morgagni. 
 
 Suspensory Ligament, connects the capsule with the ciliary body, 
 and is the anterior of the two layers formed by the splitting of the 
 zonule of Zinn (zonula ciliaris) (see p. 287). It is shown exaggerated 
 in the cut. 
 
 Canal of Petit, (spatia zonularia), is a triangular space around the 
 circumference of the lens, formed by the separation of the two por- 
 tions of the zonule of Zinn (zonula ciliaris) (shown inflated in the cut). 
 
 MUSCLES AND NERVES OF THE EYEBALL 
 
 Muscles of the Eyeball, are 6 in number, 4 Recti and 2 Oblique, which 
 are inserted into the sclerotic coat (tunica fibrosa), just behind the margin 
 of the cornea. The insertions of the superior, inferior, internal and ex- 
 ternal recti correspond to the ends of the four 
 FIG. 92. , .... 
 
 arms of an equal-armed cross, imagined to exist 
 
 behind the corneo-sclerotic junction. The inser- 
 tion of the superior oblique (14) lies between the 
 insertions of the superior and external rect, that 
 of the inferior oblique (13) somewhat behind the 
 insertion of the superior oblique. These muscles 
 are described on page 76. The tendon of the 
 superior oblique passes through a pulley or trochlea 
 on the internal angular process of the frontal bone, 
 before being inserted into the eyeball: (see Fig. 92). 
 Nerves supplying the muscles of the eyeball are the 3d, 4th and 6th 
 cranial nerves; the 3d supplies the superior, inferior and internal recti 
 and the inferior oblique, the 4th supplies the superior oblique, and the 
 6th supplies the external rectus. 
 
 VESSELS OF THE EYE 
 
 Arteries supplying the eye and its appendages are, the Ophthalmic 
 and Anterior Cerebral branches of the internal carotid artery; and the 
 Infra-orbital branch of the internal maxillary, from the external carotid. 
 The Ophthalmic Artery arises from the cavernous portion of the internal 
 carotid, enters the optic foramen to the orbit, and gives off the following 
 branches to the eye and its appendages: 
 
 Arteria Centralis Retina (2), pierces the optic nerve (i) obliquely, and 
 
 is distributed to the retina. 
 
 Muscular Branches, 2, superior and inferior, supply the muscles of 
 the eyeball, and give off the anterior ciliary (see below). 
 
2QO HUMAN ANATOMY 
 
 Lacrintal, to the lacrimal gland, the eyelids, and the conjunctiva, 
 
 anastomosing with the palpebral. 
 Supra-orbital, supplies the superior rectus and levator palpebrae 
 
 muscles. 
 Internal Palpebral (aa. palpebrales mediales), superior and inferior, 
 
 to the eyelids. 
 
 Nasal, (a. dorsalis nasi), to the lacrimal sac, and the nose. 
 Short Ciliary (aa. ciliares posteriores breves), 6 to 12, pierce the sclerotic 
 
 at the lamina cribrosa, supplying the choroid and the ciliary processes. 
 Long Ciliary (aa. ciliares posteriores longag), 2, pierce the sclerotic, and 
 
 pass forward between it and the choroid, to supply the iris, forming 
 
 two arterial circles thereon, the circulus major at the ciliary border, 
 
 and the circulus minor near the pupillary margin. 
 Anterior Ciliary (aa. ciliares anteriores) (3), arise from the muscular 
 
 branches, form a zone beneath the conjunctiva, then pierce the 
 
 sclerotic, and join the circulus major on the iris. 
 Anterior Cerebral, branch of the Internal Carotid, sends nutrient 
 
 capillaries to the optic nerve. 
 Infra-orbital, branch of the Internal Maxillary artery, sends branches 
 
 to the inferior rectus and inferior oblique muscles, and to the lac- 
 rimal gland. 
 
 Veins of the Eye are collected into two main trunks, the Superior and 
 Inferior Ophthalmic Veins, which empty into the cavernous sinus, after 
 collecting the blood from the smaller venous channels through the Vena 
 Vorticosa of the choroid. The veins of the eye anastomose freely with the 
 facial veins, thus permitting the escape of venous blood in either direction. 
 Lymph-spaces of the Eye. The principal lymph-spaces found in the 
 eyeball and its connected structures are the 
 
 Canal of Schlemm (sinus venosus sclerae), around the circumference 
 
 of the iris. 
 Peri-choroidal Space, between the choroid and the sclerotic (tunica 
 
 fibrosa). 
 Peri-sclerotic Space, between the sclerotic (tunica fibrosa) and the 
 
 capsule of Tenon (fascia bulbi), is continuous with the subdural and 
 
 subarachnoid spaces. 
 Vaginal Spaces, have been described as existing between the sheaths 
 
 of the optic nerve. 
 
 NERVES OF THE EYE 
 
 Nerves of the Eye. Besides the 3d, 4th and 6th nerves, already men- 
 tioned as supplying the muscles of the eyeball, the eye is supplied with 
 
THE EYE 
 
 291 
 
 common sensation by branches from the ophthalmic division of the 5th 
 and the ophthalmic ganglion, also motor filaments from the 5th, and its 
 special sense of sight, from the 2d or optic nerve. The 
 
 Sympathetic Branches, arise from the medulla, and the cavernous 
 and carotid plexuses, and join the 3d, 4th, 5th, and 6th nerves, send- 
 ing filaments to the dilator fibres of the iris, to the muscles of the orbit 
 and lids, to the ophthalmic ganglion, and to the walls of the arteries. 
 Short Ciliary, some 6 to 10 in number, arise from the ophthalmic 
 ganglion (see page 224), pierce the sclerotic and go to the ciliary 
 muscle, iris, cornea, and to the sheath of the optic nerve. 
 Ascending, from Meckel's (spheno-palatine) ganglion (see page 224). 
 enter the orbit by the spheno-maxillary fissure, going to the 'optic 
 nerve, the 6th nerve, and the ciliary ganglion. 
 
 FIG. 93. 
 
 CILIARY GANGLION 
 
 The Optic Nerve, 2d Cranial (Plate 6, page 244), begins at the anterior 
 part of the optic commissure, passes into the orbit by the optic foramen 
 in company with the ophthalmic artery, is pierced by the central artery 
 of the retina, and enters the eyeball posteriorly % inch inwardly from its 
 axis, piercing the sclerotic (tunic fibrosa) and choroid coats, and finally 
 expanding in the retina. f It is surrounded by a tubular process of dura 
 mater, which as the nerve enters the orbit, subdivides to form both the 
 sheath of the nerve and the periosteum of the orbit. The two nerves are 
 connected together at the commissure, from the back of which most of 
 their fibres may be traced through the optic tracts to the lower visual centres 
 
2Q2 HUMAN ANATOMY 
 
 of the brain, viz. the external (lateral) geniculate body, the upper 
 quadrigeminal body, (colliculus superior), and the pulvinar of the optic 
 thalamus. 
 
 The Optic Commissure or Chiasma (Plate 6, page 244), is seen at the 
 base of the brain in front of the tuber cinereum and behind the lamina 
 cinerea. It contains four sets of fibres, one of which decussates in the 
 commissure with its fellow set of the opposite side. The four sets of 
 fibres are arranged in the following manner: 
 
 Crossed or Decussating Fibres (i), are the most numerous; lying in the 
 centre of the commissure, they pass from the optic tract of one side 
 to the optic nerve of the other side, con- 
 necting the retina of each eye with the op- FlG * 
 posite hemisphere of the brain. 
 Uncrossed or Longitudinal Fibres (2), occupy 
 the outer sides of the commissure and 
 tracts, passing from the tracts to the nerves 
 of the same sides, and connecting the tem- 
 poral side of each retina with the cerebral 
 hemisphere of its own side. 
 
 Inter-retinal Fibres (3), in the anterior portion of the commissure, 
 pass from one optic nerve to the other, connecting the nasal sides of 
 the retinas of both eyes with each other. 
 
 Commissural Fibres (4) or Commissure of Gudden, in the posterior por- 
 tion of the commissure, have nothing to do with vision, but pass from 
 one internal (medial) geniculate body to the other, or to the op- 
 posite posterior quadrigeminal body (colliculus inferior) (Whitaker). 
 
 The Optic Tract arises from the brain by two bands, an external and an 
 internal. The external (lateral) band arises from the external (lateral) 
 geniculate body, the upper quadrigeminal body (colliculus superior) and 
 the pulvinar of the optic thalamus, the lower visual centres. The internal 
 (medial) band arises from the internal (medial) geniculate body and the 
 inferior quadrigeminal body (colliculus inferior), most of its fibres being 
 commissural between the two internal (medial) geniculates. The two 
 bands wind around the crus (cerebral peduncle) and join together opposite 
 its centre in a flattened band, which becomes cylindrical and continues on 
 to connect with the tract of the opposite side in the optic commissure. 
 In its course the tract is attached to the surface of the crus by its anterior 
 margin, and receives some fibres from the tuber cinereum and the lamina 
 cinerea (lamina terminalis). 
 
 Meynert's Commissure (fasciculus retroflexus), consists of the fibres 
 
THE EYE 293 
 
 from the epithalamic habenular nucleus, which cross in the optic 
 
 commissure and enter the crus (cerebral peduncle) on the opposite 
 
 side, passing obliquely through the red nucleus into the hypothalamic 
 
 nucleus. It is concerned with olfactory impulses. 
 
 Visual Centres in the Brain. The lower visual centres are the external 
 
 (lateral) geniculate body, the upper quadrigeminal body (colliculus 
 
 superior), and the pulvinar of the optic thalamus, to which the optic 
 
 nerve fibres are traced. From these nuclei other fibres go to the cortical 
 
 visual centre, which is located in the cuneus of the occipital lobe, and 
 
 probably also in the adjacent lingual lobule of the temporal lobe, 
 
 APPENDAGES OF THE EYE 
 
 The Tutamina Oculi (organa oculi accessoria) or appendages of the eye, 
 include the eyebrows, the eyelids, the conjunctiva, the lacrimal gland, the 
 lacrimal sac, and the nasal duct (ductus naso-lacrimalis). 
 
 The Eyebrows, or Supercilia, are two arched eminences of thickened 
 integument over the supra-orbital arches, and connected beneath with the 
 orbicularis palpebrarum, corrugator supercilii and occipito-frontalis mus- 
 cles. They are covered with short, thick hairs, and are drawn downward 
 and inward by the corrugator supercilii: (see page 75). 
 
 The Eyelids, or Palpebrae, are two thin, movable folds, placed in front 
 of the eye, for its protection. The upper lid is the more movable one, 
 having its own levator muscle, the levator palpebrae superioris. They are 
 composed externally of skin, internally of mucous membrane (the palpebral 
 conjunctiva), and between these lie areolar tissue, the orbicularis muscle, 
 tarsal cartilage, fibrous membrane, Meibomian glands (glandulae tarsales), 
 vessels and nerves. The upper lid has, in addition, the aponeurosis of 
 the levator palpebrae. 
 
 Eyelashes, or Cilia, are a double or triple row of short hairs, situated 
 on the free margins of the lids; their follicles lying in the connective 
 tissue beneath the tarsal cartilages. 
 
 Glands of Moll (glandulae ciliares), are enlarged and modified sweat- 
 glands, the openings of which are in several rows, near the attachment 
 of the eyelashes. 
 
 Palpebral Fissure (rima palpebrarum), is the space between the free 
 margin of the lids, its outer and inner angles being termed respect- 
 ively the external (commissura palpebrarum lateralis) and internal 
 (commissura palpebrarum medialis) canthus. 
 
 Lacus Lacrimalis, is a small triangular space at the internal canthus, 
 between the lids and the globe. 
 
294 HUMAN ANATOMY 
 
 Lacrimal Papilla, on the edge of each lid, about 34 inch from the 
 internal canthus. 
 
 Punctum Lacrimale, a minute orifice on each papilla, and the beginning 
 of the lacrimal canal. 
 
 Tar sal Plates (tarsi), are two thin, elongated plates of dense connect- 
 ive tissue, about an inch in length, placed one in each lid, giving it 
 form and support. The upper one is crescentic in shape, the lower 
 one is elliptical and smaller. 
 
 Tar sal Ligaments, external (ligamentum palpebralis laterale), con- 
 nects the outer angle of the tarsal plate to the malar bone. The 
 internal (ligamentum palpebralis mediale) connects the inner angle 
 of the plate to the nasal process of the maxilla. The internal one 
 is often called the tendo oculi. 
 
 Meibomian Glands (glandulae tarsales) (i), are sebaceous glands em- 
 bedded in grooves in the inner surface of the tarsal plates, about 30 
 in the upper eyelid, less in the lower 
 one. Their ducts open on the inner FlG- 95- 
 
 edge of the free margin of the lids 
 by minute foramina, through which 
 their secretion is furnished to pre- 
 vent the lids adhering to each 
 other. 
 
 Muscles, the palpebral portion of the 
 orbicularis muscle is very thin and 
 pale; the tensor tarsi compresses 
 the punctum lacrimale and the 
 lacrimal sac: (see page 75). 
 
 Arteries, are the palpebral branches of the ophthalmic artery, forming 
 the superior and inferior tarsal arches, and anastomosing with the 
 orbital branch of the temporal, the lacrimal, transverse facial, and 
 angular arteries. 
 
 Nerves y the 3d, facial, and sympathetic to the muscles; the 5th to the 
 skin and conjunctiva. 
 
 The Conjunctiva (Tunica Conjunctiva) is the mucous membrane lining 
 the inner surface of the eyelids, and reflected over the front of the sclerotic 
 and cornea. It is continuous with the mucous lining of the Meibomian 
 glands (glandulae tarsales), lacrimal ducts, lacrimal sac,naso-lacrimal duct, 
 duct and lacrimal gland. The 
 
 Palpebral Conjunctiva (tunica conjunctiva palpebrarum), consists of 
 connective tissue covered by epithelium, is traversed by furrows, and 
 has papillae, follicular glands, and lymphoid tissue. 
 
THE EYE 
 
 295 
 
 Ocular Conjunctiva (tunica conjunctiva bulbi), is very thin and 
 transparent, loosely attached on the sclerotic, firmly adherent over 
 the cornea, where it has no vessels in its structure. It has very few 
 papillae, and no glands. 
 
 Palpebral Folds, superior and inferior, are where the conjunctiva is 
 reflected over the globe, the fornix conjunctiva lying between them, 
 and containing mucous glands and trachoma glands, the latter being 
 analogous to lymphoid follicles. 
 
 Plica Semilunaris, or Semi-lunar Fold, a crescentic fold of conjunctiva 
 at the inner canthus, considered to be the rudiment of the membrana 
 nidi tans or 3d eyelid of birds. 
 
 Caruncula lacrimalis, is a small, red, conical body, situated in the 
 lacus lacrimalis, at the inner canthus of the eye; consisting of a small 
 island of skin, containing sebaceous and sweat glands, and a few 
 slender hairs. It is the source of the whitish secretion which collects 
 at the inner angle of the eye. It is connected by tendinous fibres to 
 the capsule (fascia bulbi) of Tenon and to the rectusinternus muscle. 
 
 The Lacrimal Gland (i) is an oval gland situated in a depression on 
 the orbital portion of the frontal bone, at the outer angle of the orbit, its 
 
 inferior surface resting on the eyeball, 
 its lower margin or lobe being covered 
 by conjunctiva. Its front portion is 
 separated from the rest of the gland 
 by a fibrous septum, and is called the 
 accessory gland of Rosenmiillcr (glandula 
 lacrimalis inferior). Its ducts, from 6 
 to 12 in number, open by a row of 
 orifices on the upper and outer por- 
 tion of the palpebral conjunctiva. Its 
 secretion, the tears, lubricates the sur- 
 face of the eyeball; the excess evapo- 
 rating or being collected in the lacus, 
 from which it passes through the 
 puncta (2) into the canaliculi (3) and 
 the lacrimal sac (4), and thence by the naso-lacrimal duct (5) to the 
 inferior meatus of the nose. 
 
 The Canaliculi (3) or lacrimal canals are two minute canals, ^5 inch 
 in diameter and Y$ inch long, which extend from the punctum (2) in each 
 lid to the lacrimal sac (4). They are lined with mucous membrane, 
 and enveloped by fibres of the tensor tarsi muscle. 
 
 FIG. 96. 
 
296 HUMAN ANATOMY 
 
 The Lacrimal Sac (4) is the superior dilated extremity of the nasal 
 duct (5), and is situated in the groove formed by the lacrimal bone and 
 the nasal process of the maxilla. Its form is oval, flattened antero- 
 posteriorly; its dimensions about % inch long and % inch wide. Its 
 fundus is crossed by the tarsal ligament, and by the tensor tarsi muscle. 
 Its junction with the nasal duct may be interrupted by folds of the lining 
 mucous membrane. 
 
 The Nasal Duct (ductus naso-lacrimalis) (5) is a membranous canal 
 extending from the lacrimal sac to the inferior meatus of the nose. It is 
 about % inch long, ^ inch in diameter, is contained in the osseous 
 lacrimal canal, curving downward, backward and outward, and its 
 calibre is narrowest about its middle. Its mucous lining is thick, and 
 continuous with the Schneiderian membrane of the nasal cavity. The 
 
 Valve of Hamer (plica lacrimalis), is an imperfect valve at the terminal 
 ' orifice (6) of the naso-lacrimal duct, and is formed by a fold of 
 mucous membrane. 
 
 THE EAR (AURIS OR ORGANON AUDITUS) 
 
 The Organ of Hearing is divisible into 3 parts the external ear (auris 
 externa), the middle ear (auris media) or tympanum, and the internal ear 
 or labyrinth (auris interna) ; which are situated in or upon the mastoid 
 and petrous portions of the temporal bone (described on page 20): 
 The 
 
 External Ear (auris externa), consists of the auricle or pinna, and 
 the auditory canal (meatus acusticus externus), which extends to 
 the membrana tympani. 
 
 Middle Ear or Tympanum (auris media), consists of the atrium or 
 tympanic cavity proper (cavum tympani), and the attic or epitym- 
 panic recess; it contains the membrana tympani, the ossicles of the 
 tympanum (ossicula auditus) and the tympanic orifice of the Eus- 
 tachian tube (tuba auditiva). 
 
 Internal Ear or Labyrinth (auris interna), consists of the osseous 
 labyrinth (labyrinthus osseus) and the membranous labyrinth 
 (labyrinthus membranaceus), the latter being contained within the 
 former, which comprises the vestibule (vestibulum), the semicircular 
 canals (canales semicirculares ossei), and the cochlea. The mem- 
 branous labyrinth (labyrinthus membranaceus) consists of the utricle 
 (utriculus), the saccule (sacculus), and the membranous semicircular 
 canals (ductus semicirculares), and contains the terminal filaments 
 of the auditory nerve (n. acusticus). 
 
THE EAR 297 
 
 THE EXTERNAL EAR (AURIS EXTERNA) 
 
 The Auricle or Pinna (auricula) is the external irregularly shaped 
 appendage, fastened to the malar and temporal bones by ligaments. It 
 consists of a thin plate of yellow fibro-cartilage, deficient in places where 
 its parts are joined together by fibrous tissue, and is covered by peri- 
 chondrium and integument, the latter containing sebaceous and sweat 
 glands, and provided with short, downy hairs. The Auricle presents 
 several elevations and depressions, which are due to the folding of its 
 cartilage, and are named as follows: 
 
 Helix, the outer curved edge of the pinna, beneath which is a deep 
 
 groove, the fossa navicularis (scapha) or fossa of the helix. 
 Anti-helix, a curved ridge, parallel with and in front of the helix, bifur- 
 cating above forming the crura antihelicis which enclose a triangular 
 depression, the fossa triangularis auriculae. 
 Concha Auricula, the central cavity leading into the auditory canal 
 
 (meatus acusticus externus). 
 Tragus,-^-& conical eminence in front of the concha, usually covered 
 
 with hair along its inferior border. 
 Anti-tragus, a smaller projection facing the tragus, from which it is 
 
 separated by a deep fissure, the incisura intertragica. 
 Tubercle (tuberculum auricula} of Darwin, a small tubercle frequently 
 
 seen, where the helix turns downward. 
 Lobe or Lobule Auricula, the soft, pendulous portion, composed of 
 
 integumentary, adipose and connective tissues. 
 
 Muscles of the Auricle. The extrinsic muscles are the Attollens, 
 Attrahens and Retrahens Auriculam, described on page 75. The intrinsic 
 muscles are very slightly developed (see page 79) and are the 
 / Musculus Hdicis Major, vertically on the anterior border of the helix. 
 ^_ Musculus Helicis Minor, on the lateral surface of the root of the helix. 
 Musculus Tragicus, lies vertically on the outer surface of the tragus. 
 Musculus Anti-tragicus, on the^posterior wall of the auditory canal. 
 Musculus Transversus Auricula, on the posterior surface of the auricle, 
 
 radiating outward from the convexity of the concha. 
 Musculus Obliquus Auricula, also on the posterior surface, radiating 
 
 upward from the convexity of the concha. 
 
 The Auditory Canal (meatus acusticus externus) is an osseo-cartilaginous 
 tube, about i finches long, extending from the concha to the membrana 
 tympani, and curved irregularly in its course. The cartilaginous, or 
 external portion, is about ^ inch long, and deficient posteriorly and above, 
 where it is filled by strong fibrous tissue. The canal is lined with integu- 
 
298 HUMAN ANATOMY 
 
 ment, having numerous hair follicles, sebaceous and ceruminous glands. 
 Its relations are in front, the condyle of the lower jaw; below and in front, 
 the parotid gland; behind, the mastoid cells and the lateral sinus, 
 separated from it by a very thin bony plate; above, the mastoid cells and 
 the dura mater of the brain, separated from it by a thin osseous plate. 
 The 
 
 Sulcus Tympanicus, is a circumferential groove at the bottom of the 
 
 canal for the insertion of the membrana tympani. It is interrupted 
 
 above by a notch, the incisura Rivinii. 
 
 Vessels and Nerves. The Arteries of the auricle are derived from the 
 external carotid artery, viz. the anterior and posterior auricular, and the 
 auricular branch of the occipital. Those of the auditory canal are 
 branches from the posterior auricular, internal maxillary, and temporal 
 arteries. The Nerves of the canal are derived from the temporo-auricular 
 branch of the maxillary division of the 5th, and the auricular branch of the 
 Vagus. Those of the auricle are the 
 
 Auricularis Magnus, from the cervical plexus. 
 
 Auricular, branch of the vagus (also called Arnold's nerve). 
 
 Auriculo-iemporal, branch of the mandibular div. of the 5th. 
 
 Occipitalis Major, from the post, division of the 2nd cervical nerve. 
 
 Occipitalis Minor,' from the cervical plexus. 
 
 Posterior Auricular, branch of the facial, to the muscles. 
 
 THE MEMBRANA TYMPANI 
 
 The Membrana Tympani, or Drumhead, is an oval, inelastic, semi- 
 transparent membrane, about ^50 inch in thickness, situated obliquely 
 at the bottom of the auditory canal, inclined inward and forward, so as to 
 form almost a continuation of the posterior wall of the canal. As seen 
 through the canal, it is of a delicate blue-gray color, arched inward, and 
 presents for consideration the following points: 
 
 Malleolar Eminence, white in color at the upper border, made by the 
 
 short process of the malleus behind. 
 Malleolar Stripe, also white, running downward from the eminence and 
 
 formed by the handle of the malleus behind. 
 
 Light-spot, a triangular reflection, its apex at the tip of the malleus 
 handle, its base extending to the periphery of the membrane. It is 
 due to the concavity of the exterior surface of the membrane. 
 Umbo, or Navel, is the dark, central, depressed part of the membrane. 
 ShrapnelVs Membrane (pars flaccida), is the upper posterior part of 
 the drumhead, where it is somewhat flaccid. 
 
THE EAR 
 
 2Q9 
 
 Structure. The Membrana Tympani is composed of 3 layers, an ex- 
 ternal or cuticular layer (stratum cutaneum), a middle or fibrous (mem- 
 brana propria), and an internal or mucous layer (stratum mucosum). 
 Its circumference is thickened to form an incomplete ring (annulus 
 fibrocartilagineus), which is received into the sulcus tympanicus at the 
 inner end of the auditory canal. The anterior and 
 posterior ends of this ring are shown by (z>) and (h) 
 in the figure. The 
 
 External or Cuticular Layer (stratum cutaneum), 
 is derived from the integument lining the audi- 
 tory canal (meatus acusticus externus). 
 Middle or Fibrous Layer (membrana propria), 
 consists of an outer layer of fibres which radiate 
 from the handle of the malleus; and an inner 
 layer of circular fibres, most numerous around the circumference. 
 Between these two sets of fibres are situated the short process and 
 handle of the malleus. 
 Internal or Mucous Layer (stratum mucosum), is continuous with the 
 
 mucous lining of the tympanum. 
 
 The Internal Surface of the Membrana Tympani is convex, and presents 
 the curved handle of the malleus pointing downward between its layers, 
 also the chorda tympani nerve passing along the upper margin to the iter 
 chordae anterius in the Glaserian (tympano-squamous) fissure. 
 
 Nerves and Vessels. The Membrana Tympani receives its nervous 
 supply from the auriculo-temporal branch of the mandibular, the auricular 
 branch of the vagus and the tympanic branch of the glosso-pharyngeal. 
 The Veins open into the external jugular, except those on the inner surface, 
 which drain partly into the lateral sinus and veins of the dura mater, and 
 partly into a plexus on the Eustachian tube (tuba auditiva). The 
 Arteries are the 
 
 Deep A uricular, branch of the internal maxillary, supplies the external 
 layer, and forms with the tympanic branches a capillary plexus in the 
 middle layer. 
 
 Tympanic Branches, of the internal maxillary and internal carotid arte- 
 ries, supply the internal layer, the former with the stylo-mastoid 
 artery forming a vascular circle around the membrane, and both 
 anastomosing on the membrane with the 
 Vidian (a. canalis pterygoidea), branch of the internal maxillary, and 
 
 the 
 
 Stylo-mastoid, from the posterior auricular branch of the external 
 carotid. 
 
3OO HUMAN ANATOMY 
 
 THE MIDDLE EAR OR TYMPANUM (AURIS MEDIA) 
 The Tympanum, or Drum (auris media), is an irregular cavity within 
 the petrous portion of the temporal bone, lying between the membrana 
 tympani and the tympanic surface of the petrous bone and communicating 
 with the naso-pharynx by the Eustachian tube (tuba auditiva). It 
 contains the ossicles (ossicula auditus) of the tympanum, part of the 
 chorda tympani nerve, and air. Its average diameters are about % inch 
 antero-posteriorly, ^ to % inch vertically, and 3-f 2 to ^ inch transversely. 
 It consists of two parts, the atrium or tympanic cavity proper (cavum 
 tympani), opposite the tympanic membrane; and the-fl&ix; or epitympanic 
 recess above, containing the upper half of the malleus and the greater part 
 of the incus. Its roof and floor are formed by thin osseous laminae, the 
 floor separating it from the jugular fossa and vein, and presenting, near 
 the inner wall, a small aperture for, Jacol 'son's nerve (tympanic branch of 
 the glosso-pharyngeal). The other walls cf the tympanum present for 
 examination the following points: 
 
 OUTER WALL (paries membranacea), is formed by the membrana 
 tympani and presents the 
 
 Her Chorda Posterius, opens close to the posterior edge of the drum- 
 head, for the passage of the chorda tympani nerve. 
 Her Chorda Anterius (canal of Huguier), opens just in front of the 
 
 drumhead, for the passage of the chorda tympani nerve. 
 Glaserian (tympano-squamous) Fissure, opens above and in front of 
 the drumhead, receiving the long process (processus gracilis or 
 anterior) of the malleus, the anterior ligament of the malleus, (laxator 
 tympani tendon) and the tympanic branch of the internal maxillary 
 artery. 
 
 INNER WALL (paries labyrinthica), is the outer wall of the labyrinth, 
 presents the 
 
 Fenestra Vestibuli or Ovalis, an oval opening, leading into the vestibule, 
 and closed by a membrane, to which is attached the base of the stapes. 
 Fenestra Cochlea or Rotunda, a smaller opening, below the fenestra 
 vestibuli, leading into the scala tympani of the cochlea, and closed by 
 the membrana tympani secundaria, a membrane of 3 layers. 
 Promontory, an elevation corresponding to the first turn of the cochlea, 
 situated between the fenestras and in front of them. It is grooved by 
 the tympanic plexus. 
 
 Ridge of the Aquceductus Fallopii (prominentia canalis facialis), above 
 the fenestra vestibuli, behind which it curves downward along the 
 posterior wall. 
 
 POSTERIOR WALL (paries mastoidea), separates it from the mastoid cells, 
 and presents the 
 
THE EAR 301 
 
 Opening of the Tympanic or Mastoid Antrum, which in turn com- 
 municates with the mastoid cells. 
 
 Pyramid (eminentia pyramidalis), a hollow conical eminence, behind 
 the fenestra vestibuli, contains the stapedius muscle, and a minute 
 canal communicating with the aquaeductus Fallopii (canalis facialis) 
 and transmitting a nerve to the stapedius. 
 
 ANTERIOR WALL (paries carotica), separates it from the carotid canal, 
 and presents the 
 
 Opening of Canal (semicanalis m. tensoris tympani) for the Tensor 
 Tympani Muscle, above, situated on a small projection, sometimes 
 called the anterior pyramid. 
 
 Opening of the Eusiachian Tube (semicanalis tubae auditivae), next 
 below, the two canals being separated from each other by a thin, 
 horizontal, bony plate, the processus cochleariformis (septum canalis 
 musculotubarii) . 
 
 The Ossicles (ossicula auditus) of the Tympanum are three small bones, 
 which form a chain across the tympanic cavity, connecting the mem- 
 brana tympani with the fenestra vestibuli, and named the 
 
 Malleus, or Hammer (A), consists of a head, neck, short process 
 (processus lateralis), long process or processus gracilis (processus 
 anterior), and handle or manubrium. The 
 short process and handle are fastened to the 
 middle layer of the drumhead. The long 
 process (never found in adults) is received 
 into the Glaserian (tympano-squamous) 
 fissure, and the head articulates with the 
 head of the incus. 
 
 Incus, or Anvil (B), resembles a two-pronged 
 tooth; it has a head, also a long and a short 
 process. The head articulates with the head 
 of the malleus, the short process with the fossa incudis in the epitym- 
 panic recess, the long process with the head of the stapes, by the 
 os orbictdare, its convex extremity. 
 
 Stapej,.or Stirrup (C), presents a head, neck, base and two crura. Its 
 head articulates with the incus, its base rests on the membrane clos- 
 ing the fenestra vestibuli, its neck receives the tendon of the stapedius 
 muscle. 
 
 Ligaments of the Ossicles are 5 in number, besides the capsular 
 ligaments of their articulations, 3 for the malleus, i for the incus, and i 
 for the stapes, as follows: 
 
3O2 HUMAN ANATOMY 
 
 Anterior Ligament of the Malleus, is the degenerated laxator tympani 
 muscle, from the neck of the malleus through the tympano-squamous 
 fissure or its petro-tympanic subdivision to the base of the alar 
 spine of the sphenoid. It is an active muscle in most infants and 
 about 75 per cent, of adults. 
 
 Superior of the Malleus, from the head of the malleus to the roof of the 
 epitympanic recess. 
 
 External of the Malleus, from the short process of the malleus to the 
 posterior part of the notch in the tympanic ring. 
 
 Posterior of the Incus, from the end of the short process of the incus 
 to the posterior part of the epitympanic recess. [The so-called supe- 
 rior ligament of the incus is merely a fold of mucous membrane.] 
 
 Annular Ligament of tfte Stapes (ligamentum annulare baseos stapedis), 
 around the circumference of the base of the stapes, connecting it 
 to the margin of the fenestra vestibuli. 
 
 Muscles of the Tympanum are 2, the Tensor Tympani Stapedius 
 and the laxator tympani. 
 
 Tensor Tympani, arises from the under surface of the petrous portion 
 of the temporal bone, the cartilaginous Eustachian tube (pars car- 
 tilaginea tubae auditivae), and its own osseous canal (semicanalis 
 m. tensoris tympani); and is inserted into the handle of the malleus. 
 It draws the membrana tympani inward and tense. Its nerve is a 
 branch from the trigeminal, through the otic ganglion. 
 
 Stapedius, arises from a conical cavity in the interior of the pyramid; 
 its tendon emerges from the orifice at the apex of the pyramid, and 
 is inserted into the neck of the stapes. It draws the head of the stapes 
 backward, and probably compresses the contents of the vestibule. 
 Its nerve is the tympanic branch of the facial. 
 
 Laxator Tympani, see anterior ligament of malleus (see page 80). 
 
 Vessels of the Tympanum. The Veins terminate in the pterygoid 
 plexus and in the superior petrosal sinus. The Arteries are 6 in number, 
 as follows: 
 
 Tympanic, branch of the internal maxillary, entering by the petro 
 
 tympanic fissure, anastomosing on the membrana tympani, in a 
 
 vascular circle with the Stylo-mastoid and Vidian arteries, and the 
 
 Tympanic br. of the internal carotid. 
 Stylo-mastoid, br. of the posterior auricular br. of the external carotid 
 
 entering at the stylo-mastoid foramen. 
 
 Petrosal; br. of middle meningeal artery, entering by the hiatus Fallopii. 
 Tympanic, br. from the internal carotid artery. 
 
THE EAR 303 
 
 Branch from tJie Ascending Pharyngeal,-^irom the external carotid; also 
 accompanying the Eustachian tube. 
 
 Nerves of the Tympanum. Besides the nerves supplying the two 
 muscles (see above), the Chorda Tympani Nerve enters the tympanum 
 by the iter chordae posterius, crosses the cavity between the handle 
 of the malleus and the long process of the incus, and makes its exit 
 by the iter chordae anterius, after passing close along the upper part 
 of the membrana tympani. The mucous membrane lining the 
 tympanum is supplied by the branches of distribution of the Tympanic 
 Plexus, which lies on the inner wall around the promontory, and is 
 formed by the 
 
 Tympanic Branch of the Glosso-pharyngeal, also known as Jacobson's 
 nerve, enters by an aperture in the floor near the inner wall. 
 
 Small Deep Petrosal, from the carotid plexus of the sympathetic, enters 
 from the carotid canal. 
 
 Small Superficial Pelrosal, from the otic ganglion, enters near the canal 
 for the tensor tympani muscle. 
 
 Branch from the Great Superficial Pelrosal, enters through the inner 
 wall, just in front of the fenestra vestibuli. 
 
 The Eustachian or Auditory Tube (tuba auditiva) is an osseo-car- 
 
 tilaginous canal, about i% inches long, ^2 to ^3 inch in diameter, which 
 forms a channel of communication between the tympanum and the pharynx. 
 It passes obliquely downward, forward and inward, from the anterior 
 wall of the tympanum to the naso-pharynx, where it ends in an oval orifice 
 on the side wall of the pharynx just behind the inferior meatus of the nose. 
 The osseous part (pars ossea tubae auditivae), ^ inch long, terminates 
 at the retiring angle of junction of the petrous and squamous portions 
 of the temporal bone, in a jagged margin, to which the cartilaginous part 
 (pars cartilaginea tubae auditivae) is attached. The latter, i inch long, 
 is formed by a triangular plate of elastic fibro-cartilage, folded on itself 
 above so as to leave a deficiency below, which is filled by fibrous tissue. 
 This portion of the tube expands as it descends into a trumpet-shaped 
 lower extremity. The tube is lined by ciliated mucous membrane, con- 
 tinuous with that of the tympanum and pharynx, and containing mucous 
 glands, also adenoid tissue near its lower end. The 
 
 Tube-tonsil of Gerlach, is formed by the adenoid tissue in the mucous 
 lining near the pharyngeal orifice. 
 
 Isthmus, is the narrowest part of the tube, at the junction of the 
 osseous and cartilaginous portions. 
 
 Muscles, are the dilator tubae fibres of the tensor palati (m. tensor 
 
304 HUMAN ANATOMY 
 
 veli palatini), which open the tube during deglutition, aided by the 
 salpingo-pharyngeus when present. The levator palati closes the 
 pharyngeal orifice. For these muscles see page 80. 
 
 Arteries, are the ascending pharyngeal, from the external carotid, 
 and the Vidian (a. canalis pterygoidea) from the internal maxillary. 
 
 Nerves, are pharyngeal branches from the glosso-pharyngeal, pneumo- 
 gastric and sympathetic, through the pharyngeal plexus, also the 
 upper posterior nasal branches of Meckel's (spheno-palatine) ganglion. 
 The otic ganglion lies on the outer side of the cartilaginous portion 
 of the tube (pars cartilaginea tubae auditivae), and supplies the 
 tensor palati muscle (m. tensor veli palatini). 
 
 THE INTERNAL EAR OR LABYRINTH (AURIS INTERNA) 
 
 The Internal Ear or Labyrinth is the essential part of the organ of 
 hearing. It lies internal to the tympanum, within the petrous portion of 
 the temporal bone, and consists of a series of osseous chambers, the 
 Osseous Labyrinth, containing a fluid, the perilymph, in which lies a mem- 
 branous reproduction of the chambers, the Membranous Labyrinth, which 
 also contains a fluid, the endolymph. Within the membranous labyrinth 
 are distributed the terminal filaments of the auditory nerve, which being 
 suspended between two fluids, are not only protected from injury, but 
 enabled to receive the most delicate vibrations communicated to the fluids 
 surrounding them. The Internal Ear comprises the following-named 
 structures: 
 
 f Vestibule (4), the central cavity. 
 
 Osseous Labyrinth { Semicircular Canals, behind the vestibule. 
 
 [ Cochlea (8), in front of the vestibule. 
 
 Utricle, a membranous sac, in the recessus 
 ellipticus of the vestibule. 
 I Membranous Semicircular Canals (ductus 
 
 semicirculares), in the osseous canals. 
 Membranous Labyrinth. \ _ . 
 
 Saccule, a membranous sac, in the recessus 
 
 sphaericus of the vestibule. 
 Membranous Cochlea (ductus cochlearis), a 
 spiral tube, enclosed in the osseous cochlea. 
 
 Auditory Nerve (n. acusticus), the 8th cranial nerve, Portio Mollis 
 
 of the yth pair. 
 Organ of Corti (organon spirale), the terminal auditory apparatus, in 
 
 the membranous cochlea (ductus cochlearis). 
 
THE EAR 305 
 
 Internal Auditory Meatus (meatus acusticus interims), by which the 
 auditory nerve enters from the brain. 
 
 The Vestibule (4) is the central common cavity of communication be- 
 tween the osseous parts of the internal ear, and measures in vertical diam- 
 eter about 3-15 inch, laterally about ^fo inch. It is situated internal to the 
 tympanum, behind the cochlea (8), and in 
 front of the semicircular canals (2), communi- 
 cating in front with the scala vestibuli of the 
 cochlea, and behind by five openings with the 
 semicircular canals. It contains a fluid, the 
 perilymph, also the utricle and saccule of the 
 membranous labyrinth, and presents the fal- 
 lowing points: 
 
 Fenestra Vestibuli (fenestra ovalis), on i l s 
 outer wall, closed by the base of the 
 stapes and its annular ligament. 
 Recessus Sphcericus (fovea hemisphaerica) 
 
 (7), a small circular depression on the inner wall, for the saccule, 
 medially, it presents a small area, macula cribrosa media, which is 
 perforated by 12 to 15 minute orifices for filaments of the acoustic 
 nerve. 
 Crista Vestibuli, a vertical ridge on the inner wall behind the recessus 
 
 sphaericus. It bifurcates below to enclose the 
 Recessus Cochlearis, a small depression, perforated for the passage of 
 
 about 8 filaments of the acoustic nerve. 
 
 Aquceductus Vestibuli, opens behind the crista, ending on the posterior 
 surface of the petrous portion of the temporal bone. It transmits a 
 small vein, and contains the ductus endo-lymphaticus, a tubular pro- 
 longation of the lining membrane of the vestibule, which ends in a 
 cul-de-sac between the layers of the dura mater in the cranial cavity. 
 Recessus Ellipticus or Fovea Semi-elli plica (6), a transverse oval de- 
 pression on the roof for the utricle; behind it are the 5 orifices of 
 the semicircular canals, and in front is the opening into the scala 
 vestibuli of the cochlea. 
 
 The Semicircular Canals (canales semicirculares ossei) are three C- 
 shaped bony tubes, each about >^o inch in diameter, situated above and 
 behind the vestibule, into which they open by 5 apertures. Each canal 
 lies at a right angle with the other two. The external (lateral) canals of 
 both ears are virtually in the same plane, while the superior canal of one 
 ear is in a plane parallel to that of the posterior canal of the other ear 
 
306 HUMAN ANATOMY 
 
 (Crum Brown). The superior and posterior canals are each nearly an 
 inch long, and are placed vertically; they join together behind in the crus 
 commune, which opens into the vestibule. The external canal is about ^o 
 inch long, placed horizontally, its arch being directed outward and back- 
 ward. The canals contain the perilymph, and the membranous semicircu- 
 lar canals. The 
 
 Ampulla, is a flask-shaped dilatation of each canal at one extremity, 
 having a diameter of about Ko inch. 
 
 The Cochlea is a spiral canal situated in the eburnated (ivory-like) 
 portion of the petrous bone, diametrically opposite to the internal auditory 
 canal (meatus acusticus internus). The depth at which it lies from the 
 cerebral surface of the bone varies, in different individuals, from ^4 to 
 of an inch. The promontory in 
 
 the tympanum is the only part of the 
 
 cochlea that is exposed, elsewhere it is 
 
 completely imbedded in solid bone. It 
 
 is about iM inches long, tapering from 
 
 Ho to J^o inch in diameter, coiled 
 
 around a central conical axis for 2% 
 
 turns. By removal of surrounding 
 
 bone, in conformity with its interior, 
 
 the cochlea can be made to resemble a snail-shell in appearance with 
 
 its apex pointing forward and outward. Its first turn is separated from 
 
 the carotid canal in front by a thin wall. Its central axis, the modiolus, 
 
 is of conical shape, and is channeled by small canals for the passage of 
 
 arteries and nerves, and by a central one, the^canalis centralis modioli. 
 
 Its apex is the last coil of the cochlea, and is expanded into a funnel- 
 
 shaped lamella, iheJHfrmdibidum. The 
 
 Canalis Spiralis Modioli, or Spiral Canal, is the space between the 
 modiolus and the outer wall of the cochlea. It makes 2 ; 3 4 turns ; from 
 left to right in the right ear, from right to left in the left ear, or in other 
 words, that of the right ear corresponds to a " right hand " screw; and 
 terminates in the cupola, a cul-de-sac at the apex of the cochlea. 
 It presents 3 openings, the fenestra cochlea (fenestra rotunda), 
 communicating with the tympanum; the opening into the vestibule, 
 and the orifice of the aquaeductus cochleae (see below). 
 Lamina .Spiralis (6), is a thin, osseous plate, projecting from the 
 modiolus half way across the spiral canal, and winding around the 
 modiolus terminates near the apex in a hook-like process, the Jtajnidus^ 
 Its deficiency in the last half turn of the cochlea forms the Helicotrema. 
 a space in which the two scalae unite. It consists of two laminae, 
 
THE 'EAR 307 
 
 between which pass the filaments of the cochlear nerve. From its 
 free edge the structures composing the membranous cochlea pass to 
 their attachment on the opposite wall of the cavity. It partially 
 divides the spiral canal into 2 passages, the scala vestibuli above and 
 the scala tympani below. 
 
 Aquceductus Cochlea, is a minute funnel-shaped canal which begins 
 by a small orifice in the lower wall of the scala tympani near the 
 promontory, and runs in the inner wall of the jugular fossa, ending in 
 the small deep triangular depression on the posterior border of the 
 basilar surface of the petrous portion of the temporal bone. It 
 transmits a vein from the cochlea to the jugular vein, or to the inferior 
 petrosal sinus, and forms a communication between the perilymph 
 in the scala tympani and the subarachnoidean space of the brain. 
 
 The Membranous Labyrinth (labyrinthus membranaceus) is situated 
 within the osseous labyrinth, and consists of two membranous sacs, the 
 Utricle (utriculus) (i) and Saccule (sacculus) (2), together with the Mem- 
 branous Semicircular Canals (ductus 
 FlG - IOI> semicirculares) (6), and the Membranous 
 
 Cochlea (ductus cochlearis) (5). The 
 utricle and saccule communicate with 
 each other indirectly by a small canal 
 contained in the aquaeductus vestibuli. 
 The saccule communicates with the 
 membranous cochlea by the canalis 
 
 reuniens of Hensen (4), and the mem- 
 Acastof^fUabyrmthasseen ^^ ^^^ canals Qpen into 
 
 the utricle; so that the membranous 
 
 labyrinth affords an uninterrupted channel for the endolymph which it 
 contains. The walls consist of 3 layers, an outer fibrous coat, a middle 
 one resembling the hyaloid membrane, and an inner layer, formed of 
 polygonal, nucleated epithelial cells. In the walls of the utricle and 
 saccule are contained 2 small gelatinoid bodies, the Macula Acusticce 
 which contain flask-shaped Hair Cells and 
 
 Otoliths (otoconia), minute crystals of calcium carbonate, held ta 
 
 gether in a mesh of delicate fibrous tissue in which ramify many 
 
 minute fibres of the acoustic nerve. 
 
 The Utricle (utriculus) (i) is a flattened, oblong membranous sac, 
 fastened to the inner wall of the vestibule in the fovea semi-elliptica 
 (recessus ellipticus). It is filled with endolymph, nearly surrounded by 
 perilymph, and communicates with the saccule through the small tube in 
 
308 HUMAN ANATOMY 
 
 the aquaeductus vestibuli. The membranous semicircular canals open 
 into its cavity behind by 5 orifices. The 
 
 Macula Acustica Utricularis, is a thickened spot in the wall where it is 
 lodged in the fovea (recessus), receiving the utricular filaments of the 
 acoustic nerve. 
 
 Ductus Utriculosaccularis, is given off from the medial wall; it is 
 joined by a similar duct coming from the saccule; together they form 
 the Ductus Endolymphaticus which passes through the aquaeductus 
 vestibuli. 
 
 The Saccule (sacculus) (2) is the smaller of the two membranous sacs, 
 about Hs inch in diameter, attached at one point to the utricle, and also 
 to the fovea hemispherica (recessus sphaericus) of the vestibule, being else- 
 where surrounded by perilymph, and containing endolymph. It com- 
 municates with the utricle through the ductus endolymphaticus in the 
 aquaeductus vestibuli, and also with the membranous cochlea by the 
 Canalis Reuniens of Hens en (4), about ^5 inch long and K 20 inch in 
 diameter,- connects the cavity of the saccule and the vestibular end 
 of the membranous cochlea (ductus cochlearis) (3). 
 Macida Acustica Saccularis, is a circular area, ^2 inch in diameter, 
 on the wall of the saccule, where the saccular filaments of the acoustic 
 nerve originate. 
 
 FIG. 102. 
 
 The Membranous Semicircular Canals (ductus semicirculares) have 
 the same shape as the osseous ones in which they are contained but are 
 Yz their diameter. They are fastened thereto by the convex curves, and 
 are elsewhere surrounded by perilymph, except at the ampullary enlarge- 
 
THE EAR 309 
 
 ments, where they fill the osseous canals and present a thickened fiddle- 
 shaped elevation projecting into the cavity and called the septum trans- 
 versum, in which the nerves end. They are held in position by numerous 
 fibrous bands, connecting them to the walls of the osseous canals. They 
 constitute the Organ of Orientation and Equilibration. 
 
 The Membranous Cochlea, also called the Ductus Cochlearis or Scala 
 Media, is a spiral tube enclosed in the spiral canal of the osseous cochlea 
 (16), lying along its outer wall, to which it is attached, being also attached 
 to the lamina spiralis (10) on the opposite side of the cavity. It is formed 
 by the membrana or lamina basilaris (8) below, the vestibular membrane 
 of Reissner (18) above, and the periosteum of the cochlear wall on the outer 
 side, its cross-section being of triangular form. It is filled with endolymph, 
 and contains the organ of Corti (organon spirale) (n) overhung by the 
 membrana tectoria (7). The 
 
 Limbus Lamina Spiralis (10), is the soft structure of periosteum on 
 the edge of the lamina spiralis, and lies in the membranous cochlea. 
 It has two lips, an upper, the labium vestibulare, and a lower, the 
 labium tympanicum, with a C-shaped concavity, the sulcus spiralis 
 internus, between them. 
 
 Vestibular Membrane of Reissner (18), extends from the edge of the 
 lamina spiralis to the outer cochlear wall, separating the membranous 
 cochlea from the scala vestibuli (2). 
 
 Membrana or Lamina Basilaris (8), is the tympanic- wall of the mem- 
 branous cochlea, extending from the labium tympanicum of the 
 lamina spiralis to the outer cochlear wall, where its insertion is 
 called the ligamentum spirale (5), or muscle of Todd and Bowman. 
 On it rests the Spiral Organ of Corti (n), covered by the mem- 
 brana tectoria. 
 
 Membrana Tectoria (7), extends parallel to the membrana or lamina 
 basilaris from the 'abium vestibulare, over the spiral organ of Corti, 
 to be attached externally to the outer row of Deiters' cells (see below). 
 Vas Spirale (9), a vessel in the vascular connective tissue of the mem- 
 brana or lamina basilaris, below the spiral organ of Corti. 
 Zona Arctuala, is the inner area, and the zona pectinata is the outer 
 area, of the membrana or lamina basilaris. 
 
 The Organ of Corti (organon spirale) (n),or Papilla Spiralis, is situated 
 on the inner surface of the membrana or lamina basilaris (8), is overlapped 
 by the free edge of the membrana tectoria (7), and appears as a papilla 
 winding spirally throughout the length of the membranous cochlea. 
 It is an arrangement of cells, some of which are rod-like in form, and others 
 
3 10 HUMAN ANATOMY 
 
 are epithelial hair-cells, the whole being supposed to be the essential organ 
 
 of hearing. The 
 
 Rods of Corti, are arranged in two rows, resting, by their pedestals, 
 on the lamina basilaris, and uniting with each other by their heads, 
 so as to form an arched tunnel, the tunnel of Corti, between them and 
 the membrana basilaris all along the length of the cochlea. Number 
 of rods in inner row about 6,000, in outer row 4,000. Average di- 
 ameter of the rods, from Msooo to Hsooo inch. 
 Head-plates, are attached to the heads of the inner rods, for the recep- 
 tion of the rods of the opposite row. 
 
 FIG. 103. 
 
 Lamina Reticularis (i), a delicate perforated membrane which extends 
 from the articulations of the rods outward to the external row of 
 the outer hair-cells. 
 
 Auditory Cells (2), are epithelial structures covering the inner surfaces 
 of the walls and the floor of the membranous cochlea. Those which 
 cover the inner rods by a single row number about 3,500, are nucleated, 
 covered with tufts of cilia, and called the inner hair-cells. On the 
 outer rods are 3 or 4 rows of similar cells, numbering about 12,000, 
 and named the outer hair-cells. Between the latter are rows of sup- 
 porting cells, called the cells of Deiters, and outside them are 5 or 6 
 rows of columnar cells, the cells of Hensen, beyond which are the cells 
 of Claudius, covering the outer part of the zona pectinata of the 
 membrana or lamina basilaris. 
 
 The Auditory Nerve (n. acusticus), the 8th or Portio Mollis of the ;th 
 pair, arises by two roots from the same groove in the medulla as does the 
 facial nerve which is in front and separated from it by the pars intermedia, 
 or glosso-palatine nerve (n. intermedius), the medial or vestibular root from 
 the area acustica or trigonum acusticum in the floor of the 4th ventricle, 
 the lateral or cochlear root from the accessory nucleus and the tuberculum 
 acusticum, in the medulla, close to the restiform body. It emerges from 
 the medulla at the lower border of the pons Varolii, in company with the 
 facial nerve, from which it receives one or two filaments, both nerves 
 
 
THE EAR 311 
 
 passing into the internal auditory meatus, at the bottom of which the 
 auditory divides into two branches, vestibular and cochlear. The 
 Vestibular Nerve, has a ganglion, the vestibular ganglion of Scarpa, 
 on it in the internal auditory meatus; it then divides into 3 branches, 
 which pass through minute orifices in the bottom of the meatus, and 
 entering the vestibule, are distributed to the utricle and the ampullae 
 of the external and superior semicircular canals respectively. This 
 nerve has nothing to do with hearing, it is purely a nerve of orientation 
 and equilibration. 
 
 Cochlear Nerve, is the true nerve of hearing, it gives off branches to the 
 saccule and the ampulla of the posterior semicircular canal, and then 
 divides at the base of the modiolus of the cochlea into numerous 
 filaments (14), which pass through the little foramena in the tractus 
 spiralis foramenosus at the bottom of the internal acoustic meatus, 
 then between the lamellae of the lamina spiralis, and through the 
 central canal of the modiolus, to the hair-cells of the spiral organ 
 of Corti (Fig. 101). On it in the spiral canal of the modiolus is 
 the 
 
 Ganglion S pirate (13), consisting of bipolar nerve-cells, which are the 
 true cells of origin of this nerve, one pole being prolonged centrally 
 to the brain, and the other peripherally to the hair-cells of Corti's 
 spiral organ (see lateral lemniscus, page 199). 
 
 The Internal Auditory Meatus (meatus acusticus internus) is a large 
 orifice on the cerebellar surface of the petrous portion of the temporal 
 bone, leading into a short canal, which runs outward for % inch, and is 
 closed by a vertical plate, thefundus or lamina cribrosa, divided by a crest, 
 the crista falciformis (crista transversa), into 4 depressions, which are 
 perforated by foramina for the passage of the branches of the auditory 
 nerve into the labyrinth. The 
 
 Tractus Spiralis Foraminosus, is the anterior lower depression; has a 
 number of foramina spirally arranged and opening into the central 
 canal of the cochlea, transmitting the nerves to the cochlea. 
 Area Cribrosa Media (area vestibularis inferior), just below the 
 
 posterior part of the crest, transmits the nerves to the saccule. 
 Foramen Singulare, behind the preceding area, for the nerve to the 
 
 posterior semicircular canal. 
 
 Area Cribrosa Superior (area vestibularis superior), above the crest 
 posteriorly, for the filaments to the utricle and the superior and 
 external semicircular canals. 
 
 Opening of the Aquaductus Fallopii (area n. facialis) above and in front, 
 for the passage of the facial nerve. 
 
HUMAN ANATOMY 
 
 Vessels of the Internal Ear. The Veins accompany the arteries, and 
 uniting at the base of the modiolus empty into the superior petrosal sinus 
 or into the lateral sinus. The Arteries are the 
 
 Internal Auditory, br. of the basilar (from the vertebral), accompanies 
 the acoustic nerve into the internal auditory meatus, where it divides 
 into vestibular and cochlear branches. 
 
 Stylo-mastoid, br. of the posterior auricular (from the external carotid), 
 sends some small branches to the cochlea. 
 
 ORGANS OF DIGESTION (APPARATUS 
 DIGESTORIUS) 
 
 The Alimentary Canal is a musculo-membranous tube, about 30 feet 
 in length, extending from the mouth to the anus, lined throughout with 
 mucous membrane, furnished with several accessory organs, and perform- 
 ing the functions of ingestion, mastication, insalivation, deglutition, 
 digestion, assimilation, and egestion. Its subdivisions are named the 
 Mouth, Pharynx, (Esophagus, Stomach, Small Intestine (duodenum, 
 jejunum and ileum) and Large Intestine (caecum, colon and rectum). 
 The first three lie above the diaphragm, the rest below it. The portion 
 from the pharynx down is the "tubus digestorius." 
 
 Accessory Organs of Digestion are the Teeth, Salivary glands (pa- 
 rotid, sub-mandibular, sub-lingual), Liver, and Pancreas. 
 
 THE MOUTH (CAVUM ORIS) 
 
 The Mouth is an oval-shaped cavity, placed at the commencement of 
 the alimentary canal, and consists of the vestibule, and the cavity proper. 
 The vestibule (vestibulum oris) is a slit-like aperture between the lips and 
 cheeks externally and the gums and teeth internally. It is partially 
 interrupted in front in the mid-line by ihejrenula which attach the lips 
 to the gums, the frenulum of the upper lip being the more developed of the 
 two. The cavity proper (cavum oris proprium) extends from the alveolar 
 arches and their teeth in front and laterally to the isthmus of the fauces 
 behind, by which constricted aperture it communicates with the pharynx. 
 Its roof is formed by the palate, its floor by the tongue and its mucous 
 membrane reflected to the lower gum. The lips (labia oris) are the two 
 fleshy folds, which surround the orifice (rima oris) of the mouth, the cheeks 
 (buccae) forming its sides and being continuous with the lips in front; both 
 are formed of skin externally, and mucous membrane internally; between 
 which are muscle, fat, areolar- tissue, vessels, nerves and glands. The 
 
THE PALATE 313 
 
 mouth presents for examination the tongue (see page 272), the gums and 
 teeth (described separately), the palate, fauces, tonsils, and openings of 
 ducts from the salivary glands. Special anatomical features presented 
 by the mouth are the 
 
 Hamular Process of the Medial Pterygoid Lamina of the Sphenoid Bone, 
 
 may be felt behind the last upper molar tooth; also the internal ptery- 
 
 goid plate (medial pterygoid lamina), and part of the pterygoid fossa. 
 Coronoid Process, of the lower jaw, at its anterior border. 
 Posterior Palatine Artery, at the inner side of the last upper molar 
 
 tooth, and in front of the hamular process. 
 Pterygo-mandibular Ligament, is felt as a fold posteriorly to the last 
 
 lower molar tooth. 
 Lingual Branch of the $th, the gustatory nerve, passes over the inner 
 
 side of the ramus of the lower jaw, close to the last lower molar tooth. 
 Openings of Stenson's Ducts, from the parotid glands, in the vestibule, 
 
 one on each cheek, opposite the 2nd upper molar tooth. 
 Openings of Wharton's Ducts, from the submandibular or submaxillary 
 
 glands, in the cavity proper, one on each side of the f raenum (frenu- 
 
 lum linguae) of the tongue. 
 Openings of the Ducts of Rivinus, from the sublingual glands, 8 to 20 
 
 on each side, open into the cavity proper, on either side of the fraenum 
 
 (freiiulum linguae) of tbe tongue. 
 
 THE PALATE (PALATUM) AND TONSILS (TONSILL.E "PALATINE) 
 
 The Palate forms the roof of the mouth, and consists of the hard palate 
 (palatum durum) in front, and the soft palate (palatum molle) behind. 
 The Hard Palate (palatum durum) is formed by the palate process of the 
 maxilla and the horizontal plate of the palate bone, is covered with 
 mucous membrane, which is closely adherent to the periosteum, and 
 presents along the median line, a linear ridge orjaphe, which terminates 
 anteriorly in a papilla corresponding to the inferior opening of the 
 anterior palatine fossa. The Soft Palate (palatum molle) is a movable 
 fold suspended from the posterior border of the hard palate, and 
 forming an incomplete septum between the mouth and the pharynx. 
 It consists of a fold of mucous membrane, enclosing muscular fibres, an 
 aponeurosis, adenoid tissue, vessels, nerves and mucous glands; and is 
 formed by fibres of the following 
 
 Muscles, 5 on each side, the levator palati, tensor veli palati, palato- 
 glossus (m. glosso-palatinus) , palato-phafyngeus (m. pharyngo- 
 palatinus), and the azygos uvulae (m. uvulae); the latter forming 
 with its fellow the " 
 
314 HUMAN ANATOMY 
 
 Uvula, a conical-shaped, pendulous process, which hangs down from 
 the middle of the free border of the soft palate. 
 
 Glosso- palatine Arch or Anterior Pillar of the Fauces, arches downward 
 and forward to the base of the tongue, and contains the glosso-palatine 
 muscle. 
 
 Pharyngo-palatine Arch or Posterior. Pillar of the Fauces, arches down- 
 ward and backward to the sides of the pharynx, and contains the 
 palato-pharyngei (m. pharyngo-palatinus) muscle. 
 
 Isthmus Faucium, the space bounded by the glosso-palatine arches of 
 both sides, the free border of the palate, and the base of the tongue. 
 It communicates with the mouth anteriorly and with the pharynx 
 posteriorly. 
 
 The Tonsils (tonsillae palatinae) or A mygdalee, are two prominent bodies, 
 situated one on each side, in the sinus tonsillaris between the anterior and 
 posterior pillars (glosso-palatine and pharyngo-palatine arches) of the 
 fauces, and nearly an inch in front of the internal carotid artery. Their 
 inner surfaces show 12 to 15 orifices, leading into recesses, from which 
 follicles branch out into the substance of the gland. The follicles are 
 numerous, and are surrounded by a layer of closed capsules of adenoid 
 tissue, and a plexus of lymphatic vessels communicating with the deep 
 cervical glands. The 
 Fossa Supra-tonsillaris, is a recess above the tonsil, and is covered by 
 
 the plica semilunaris, a fold of mucous membrane. 
 Arteries, as usually given, are the dorsalis linguae, from the lingual; the 
 ascending palatine and tonsillar, from the facial (a. maxillaris 
 externa); the ascending pharyngeal, from the external carotid; 
 the descending palatine; from the internal maxillary; and a twig 
 from the small meningeal. As a matter of fact, in 95 per cent, of 
 all cases none of these arteries that surround the tonsillar fossa 
 (sinus tonsillaris) and form a plexus around it, actually penetrate 
 directly through the wall and capsule into the tonsil. The ascending 
 palatine branch of the facial (external maxillary) and the^escendin^ 
 palatine branch of the internal maxillary arteries form a plexiform 
 anastomosis which is quite outside of the fossa (sinus tonsillaris) 
 and well above and behind it. 
 
 The True Tonsillar Artery is formed by this anastomosis, it passes 
 
 downwards between the capsule and muscular aponeurosis for a 
 
 distance of about % inch before penetrating the capsule to reach 
 
 the tonsil (J. Leslie Davis). 
 
 Veins, accompanying the true tonsillar artery is a vein which runs 
 
THE SALIVARY GLANDS 315 
 
 upwards to the palatine plexus, a smaller vein emerges from the tonsil 
 in company with the other vein, then turns downwards and runs be- 
 tween the capsule and the wall of the fossa (sinus tonsillaris) to reach 
 the pharyngeal plexus (J. Leslie Davis). 
 
 Nerves, are derived from the spheno-palatine ganglion, and from the 
 glosso-pharyngeal. 
 
 THE SALIVARY GLANDS (GLANDULE SALIVALES) 
 
 The Salivary Glands, communicating with the mouth, are the Parotid, 
 the Stibmandibular, and the Sublingual glands. They are compound, race- 
 mose glands, consisting of numerous lobes, made up of smaller lobules 
 connected together by dense areolar tissue, vessels and ducts. Each lobule 
 consists of the ramifications of a duct, the branches terminating in dilated 
 ends or alveoli, on which the capillaries are distributed, and which are 
 enclosed by a reticulated basement membrane. The alveoli are lined by 
 cells, which secrete a mucous secretion in the sublingual gland, or a serous 
 fluid in the parotid gland; the submandibular producing both kinds. 
 Mucous Glands are also found in the mouth, in the tongue, the tonsil, and 
 the soft palate. 
 
 The Parotid Gland (glandula parotis) (i) is the largest of the three 
 salivary glands, and weighs from % oz. to i oz. Superficially, it lies upon 
 
 the side of the face, below and in 
 front of the external ear, and passes 
 over the masseter muscle anteri- 
 orly. Deeply, it lies on the tym- 
 panic plate of the temporal bone 
 behind the articulation of the 
 lower jaw. The parotid is sur- 
 rounded by a capsule which blends 
 deeply with the back of the stylo- 
 mandibular ligament. The super- 
 ficial portion of this capsule is the 
 parotid fascia (fascia parotideo- 
 masseterica). The capsule is de- 
 rived from the deep cervical fascia, 
 
 it is strongly attached to the lower border of the zygoma, the acoustic 
 meatus, anterior border of the sterno-mastoid muscle, stylo-mandibular 
 ligament, and the bucco-pharyngeal fascia. It is tenaciously adherent 
 to the gland itself. Passing through it are the following 
 
 Structures, the external carotid artery and its terminal branches, the 
 posterior auricular, temporal, and internal maxillary; the vein formed 
 
HUMAN ANATOMY 
 
 by the union of the temporal and internal maxillary veins, the facial 
 nerve and its branches, branches of the great auricular nerve, and the 
 auriculo-temporal branch of the mandibular nerve. The internal 
 carotid artery and the internal jugular vein lie close to its deep 
 surface. 
 
 Stenson's Duct (ductus parotideus) (2), is the duct of the parotid 
 gland, and is about 2^ inches long. It begins by numerous branches 
 from the anterior part of the gland, crosses the masseter muscle, 
 pierces the buccinator, and opens on the inner surface of the cheek 
 by a small orifice opposite the 2nd molar tooth of the upper jaw. 
 
 Soda Parotidis, is a small, detached portion of the gland, which 
 occasionally exists as a separate lobe, just beneath the zygomatic 
 arch. Its duct empties into Stenson's duct, where the latter crosses 
 the masseter muscle. 
 
 Arteries, are derived from the external carotid. 
 
 Veins, empty into tributaries of the external jugular. 
 
 Lymphatics, terminate in the superficial and deep cervical glands. 
 
 Nerves, are derived from the carotid plexus of the sympathetic, the 
 facial, auriculo-temporal and great auricular nerves. 
 
 % 
 
 The Submandibular Gland (glandula submaxillaris) (3) lies below the 
 jaw, in the anterior part of the submandibular triangle, and upon the 
 mylo-hyoid, hyo-glossus, and stylo-glossus muscles, the facial artery (a. 
 maxillaris externa) lying embedded in a groove in its upper, posterior 
 border. Its duct 
 
 Wharton's Duct (ductus submaxillaris) (4), is about 2 inches long, and 
 opens on the summit of a papilla at the side of the fraenum of the 
 tongue. 
 Arteries, are branches of the facial (external maxillary) and the lingual; 
 
 the veins following the course of the arteries. 
 
 Nerves, are branches of the submandibular or submaxillary ganglion, 
 and are derived through the ganglion from the chorda tympani, the 
 lingual, and the sympathetic. 
 
 The Sublingual Gland (glandula sublingualis) (5) is the smallest of the 
 salivary glands, and is situated beneath the mucous lining of the floor of 
 the mouth, at the side of the fraenum (frenulum linguae) of the tongue, and 
 in contact with the inner surface of the lower jaw. Its ducts, the 
 Ducts of Rivinus (ductus sublinguales minores), from 8 to 20 in num- 
 ber; some join Wharton's duct (ductus submaxillaris), others open on 
 the side of the frenulum linguae. 
 
THE TEETH 
 
 317 
 
 Duct of Bartholin, is a tube formed by one or more of the preceding 
 
 ducts; it opens into Wharton's duct (ductus submaxillaris). 
 Arteries, are derived from the sublingual and submental. 
 Nerves, are branches from the lingual nerve. 
 
 THE TEETH (DENTES) 
 
 The Teeth are 32 organs of digestion, situated 16 in each jaw, where 
 they are implanted within the alveoli, and are partly surrounded by the 
 gums. In each half of each jaw there are 
 
 Deciduous or Temporary Teeth (dentes dicidui) (5) 2 Incisors, i 
 Canine, 2 Milk-molars. 
 
 Permanent Teeth (dentes permanentes) (8) 2 Incisors, i Canine, 2 
 Premolar, 3 Molars. 
 
 The Gums (gingivae) are composed of dense fibrous tissue, closely 
 connected to the periosteum of the alveolar processes, and surrounding the 
 necks of the teeth. They are covered with mucous membrane, presenting 
 numerous fine papillae around the dental margin, and reflected into the 
 alveoli, where it is continuous with the periosteal lining membrane. 
 
 Characteristics of the Teeth. Each tooth consists of a crown (corona 
 dentis) or body, projecting above the gum; root or fang (radix dentis), 
 
 embedded within the alveolus; and the neck (collum dentis), the constricted 
 portion between the crown and the fang. The roots are entirely con- 
 cealed within their alveoli, and are covered by the pericementum (perios- 
 teum alveolare), a reflection of the periosteum lining the alveoli, which 
 becomes continuous with the fibrous structure of the gums. The pulp- 
 cavity (cavum dentis) occupies the centre of the tooth, opening (foramen 
 apicis) at the apex of the fang for the passage of vessels and nerves to 
 the pulp (pulpa dentis) . Each class of teeth presents the following charac- 
 teristics: 
 
HUMAN ANATOMY 
 
 FIG. 107. 
 
 Incisors, or Cutters (denies incisivi) (i), Crown chisel-shaped, beveled 
 
 posteriorly. Fang single, long, thickest antero-posteriorly. 
 Canines, or Tearers (dentes canini) (2), Crown thick and conical. 
 Fang longest and thickest of all the teeth, forming a projection on the 
 alveolar arch. The 2 upper canines are the "eye-teeth." 
 Premolars, or Bicuspids (dentes prasmolares) (3), Crown has 2 cusps 
 (tubercles). Fang single but grooved deeply, showing a marked 
 tendency to bifurcate. 
 
 Molars, or Grinders (dentes molares) (4), Crown large, low and cuboid 
 in shape, has 4 cusps on upper molars, 5 on the lower ones. Fangs 
 multiple, usually 3 on the first two upper 
 molars, 2 on the first two lower ones. The 
 third molar (dentes serotini) (5) is called 
 the "wisdom-tooth," from its late eruption; 
 its fangs are usually fused together into a 
 grooved cone. 
 
 Structure of the Teeth. A tooth consists of 3 
 structures, the dentine, or ivory (substantia 
 eburnea) the proper dental substance, forming 
 the larger portion; the enamel or adamant (sub- 
 stantia adamantina), a layer covering the crown; 
 and the cement (substantia ossea), a thin layer 
 on the surface of the fang. A central chamber, 
 the pulp-cavity (cavum dentis), occupies the in- 
 terior, and contains the pulp (pulpa dentis), a 
 soft, vascular, and sensitive organ, surrounded 
 by a layer of cells the odonto-blasts or dentine- 
 forming cells. The 
 
 Pulp-cavity (cavum dentis), has a process ex- 
 tending down each root, and opening at the 
 apex by a minute orifice (foramen apicis) 
 which transmits vessels and nerves to the 
 pulp. 
 
 Pulp (pulpa dentis), is made up of myxoma- 
 tous tissue, and contains numerous blood- 
 vessels and nerves, but no lymphatics. 
 Dentine, or Ivory (substantia eburnea) (2), consists of tubules (can- 
 aliculi dentales) surr< unded by the inter-tubular tissue or matrix, and 
 opening into the pulp cavity (cavum dentis). It resembles compact 
 bone in appearance and in composition, consisting of 28 parts animal 
 matter and 72 earthy matter. 
 
THE TEETH 3 19 
 
 Dentinal Tubidi (canaliculi dentales), in the dentine, are delicate, 
 wavy canals, diameter about M 5 o o of an inch, which branch outwardly 
 and anastomose with each other, forming concentric shadings called 
 Schreger's lines. They contain slender prolongations from the proc- 
 esses of the cells of the pulp-tissue. 
 
 Enamel (substantia adamantina) (3), covers the crown; consists of 
 very dense tissue, containing but 3^ per cent, of animal matter. 
 Its earthy matter, 96 ^ per cent., is composed chiefly of the phos- 
 phate and carbonate of calcium. It is covered by a delicate epithelial 
 cuticle, Nasmyth's Membrane (cuticula dentis), which when intact 
 withstands the action of acids. 
 
 Crusta Petrosa (substantia ossea) or Cement (i), the enamel of the 
 fang; is a thin layer of true bony tissue, containing lacunae, canaliculi, 
 and occasionally Haversian canals. 
 
 Development of the Teeth. The teeth are evolved from the dermoid 
 system, not from the skeleton. They are developed from two of the primi- 
 tive layers of the embryo, the epiblasl producing the enamel (adamant) 
 and the mesoblast giving rise to the dentine (ivory) pulp, cement (sub- 
 stantia ossea), and pericementum (periosteum alveolare). About the 
 7th week of foetal life, two parallel ridges arise along the summit of each 
 jaw, and a corresponding epithelial lamina sinks into the mesoblastic tissue 
 beneath. This lamina sends off 10 cords, one for each tooth, from its inner 
 edge; the cords expand into flask-like forms, and gradually assume 
 the forms of the teeth, constituting their enamel-organs. They meet and 
 enclose papilla, which arise from the mesoblastic tissue, forming a series 
 of sacs, which with their contents are the dental follicles, having fibrous 
 septa between them. In each follicle the vascular papilla has on its 
 surface a layer of cells, named odontoblasts, from which the dentine (ivory) 
 is developed by calcification, the remainder of the papilla forming the pulp 
 of the tooth. The cement (adamant) is produced later by the tissue of 
 the dental sac, in the same manner as bone is produced by periosteum. 
 When calcification has advanced sufficiently, the pressure of the teeth 
 causes the absorption of the gum above them, the teeth erupt, and the 
 fibrous septa ossify, forming the alveoli, which embrace the necks of the 
 teeth in a firm hold. 
 
 The 10 permanent teeth, which replace the temporary ones in each jaw, 
 are developed from special germs (enamel-organs) which arise from the 
 lamina behind the germs for the temporary teeth, and recede into the 
 tissue, to enclose mesoblastic papillae, and go through the same process 
 as described for the temporary teeth. These germs appear about the i6th 
 
320 HUMAN ANATOMY 
 
 week. The 6 superadded permanent teeth arise from successive back- 
 ward extensions of the lamina, projected from the back of that tor each 
 preceding tooth, and thus forming a special dental germ for each added 
 tooth. 
 
 Eruption of the Teeth. The temporary teeth begin to appear through 
 the gum at the 7th month after birth, the lower central incisors appearing 
 first. Their eruption ends with the appearance of the second molars, 
 about the age of two years. The lower teeth slightly antedate the upper. 
 Their formula is as follows : 
 
 Mo. Mo. Ca. In. In. In. In. Ca. Mo. Mo. 
 f Upper. ,.i i i i i i i i i i = 10 1 
 
 j \. = 20 
 
 [ Lower. .. i i 1111111 i =ioJ 
 24 12 18 9 7 7 9 18 12 24 months. 
 
 Of the permanent teeth, the first molars appear about the end of the 6th 
 year, followed by the incisors about the 7th or 8th year, the bicuspids 
 from the 9th to the loth year, the canines about the nth or i2th year, 
 the second molars from the i2th to the i3th year, and the third molars 
 from the i7th to the 2ist year. Those of the lower jaw are slightly in 
 advance of the corresponding upper ones. Their formula is as follows: 
 
 Wis.Mo.Mo.Pm.Pm.Ca.In.In.In.In.Ca.Pm.Pm.Mo.Mo.Wis. 
 r Upper, i i i i i i iiiiii i i i 1=16] 
 
 f 32 
 
 I Lower, i i i i i 1111111 i i i i = 16 J 
 19 12 6 10 9 ii 8 7 7 8 n 9 10 6 12 19 years. 
 
 The greatest number of teeth at one time in the jaws is 48, including all 
 the temporary and permanent teeth except the third molars, if none have 
 been lost. This occurs between the 5th and 7th years of age. 
 
 THE PHARYNX 
 
 The Pharynx is a conical, musculo-membranous tube, about 4^ inches 
 long, hung base up from the basilar process of the occipital bone, and 
 extending to the lower border of the cricoid cartilage posteriorly, or the 
 5th cervical vertebra, where it becomes continuous with the oesophagus (5). 
 It forms that part of the alimentary canal which lies behind the mouth, 
 being incomplete in front where it opens into that cavity. From above 
 downward it may be divided into the naso-pharynx (pars nasalis), 
 above the level of the soft palate; the oral part (pars oralis), between 
 
THE PHARYNX 
 
 321 
 
 FIG. 108. 
 
 the levels of the soft palate and the hyoid bone; and the laryngeal part 
 (pars laryngea), below the latter level. It is connected with 
 Anteriorly, the internal pterygoid plate, pterygo-mandibular ligament, 
 lower jaw, base of the tongue, cornua of the hyoid bone, stylo-hyoid 
 ligament, thyroid and cricoid cartilages of the larynx. 
 
 Posteriorly, the longus colli and recti 
 capitis anticus muscles, and by loose 
 areolar tissue to the first 5 cervical 
 vertebrae. 
 
 Laterally, the styloid processes and 
 their muscles, and is in contact with 
 the common and internal carotid arte- 
 ries, the internal jugular vein, the Qth, 
 loth, 1 2th and sympathetic nerves, 
 and above with a small part of the 
 internal pterygoid muscles. 
 Above, it is limited by the body of the 
 sphenoid bone, and the basilar process 
 of the occipital bone. 
 Openings into the Pharynx, are 7 in 
 number; the 2 posterior nares, (choanse), 
 the 2 Eustachian tubes (tubae audi- 
 tivae), the mouth, the larynx and the 
 oesophagus. 
 
 The Naso -pharynx (pars nasalis pharyn- 
 gis) is that portion of the pharynx lying be- 
 hind the nose and above the level of the 
 soft palate. Its cavity, unlike the rest of 
 the pharynx, always remains open. The 
 Eustachian Tube (tuba auditiva), opens 
 on its lateral wall, by a cleft-like orifice 
 (ostium pharyngeum tubae auditivae), 
 behind the inferior meatus of the nose, 
 and just above the level of the floor of 
 the nasal fossa. 
 
 Pharyngeal Tonsil, a mass of lymphoid 
 tissue, in the back wall of the pharynx, 
 between the two Eustachian tubes (tubae auditivae). 
 Bursa Pharyngea, an irregular depression of the mucous membrane 
 
 in the jniddle line of the pharynx, above the pharyngeal tonsil. 
 Cushion (torus tubarius) or Tubal Prominence, immediately behind 
 
322 HUMAN ANATOMY 
 
 the orifice of the Eustachian tube (ostium pharyngeum tubae auditivae), 
 
 due to the pressure of the extremity of the cartilage of the tube. 
 
 Fossa ofRosenmiiller, a deep recess, behind the cushion (torus tubarius). 
 
 Structure of the Pharynx. The pharynx is composed of 3 coats, a 
 
 mucous, a muscular and a fibrous, the latter lying between the other two, 
 
 and called the pharyngeal aponeurosis (fascia pharyngo-basilaris) (4). 
 
 The mucous coat is covered with ciliated columnar epithelium above the 
 
 level of the floor of the nares below that level with squamous epithelium; 
 
 and contains racemose mucous glands, especially around the orifices of the 
 
 Eustachian tubes (ostia pharyngea tubarum auditivarum), also numerous 
 
 crypts or recesses, surrounded by lymphoid tissue. The 
 
 Pharyngeal Aponeurosis (fascia pharyngo-basilaris) (4), is thick 
 above, where it is firmly attached to the basilar process of the 
 occipital bone, and the petrous portion of the temporal bone. Pos- 
 teriorly it presents a fibrous band or raphe in the median line, which 
 gives attachment to the constrictor muscles. 
 
 Muscles, are the inferior (i), middle (2), and superior (3) constrictors 
 of the pharynx, the stylo-pharyngeus and the palato-pharyngeus (m. 
 pharyngo-palatinus), which have been described on page 83. 
 Vessels and Nerves. The Arteries of the pharynx are the superior 
 thyroid and ascending pharyngeal, also the pterygo-palatine and descend- 
 ing palatine branches of the internal maxillary; all from the external 
 carotid. The nerves are branches from the 
 
 Pharyngeal Plexus, formed by the pharyngeal branches of the vagus, 
 glosso-pharyngeal, external br. of the superior laryngeal, and superior 
 cervical ganglion of the sympathetic. 
 
 ? *> !?*y THE (ESOPHAGUS OR GULLET 
 
 The (Esophagus is a musculo-membranous tube, about 9 inches long, 
 extending from the 5th cervical vertebra and the upper border of the 
 cricoid cartilage of the larynx, through the cesophageal opening (hiatus 
 oesophageus) in the diaphragm to the cardiac orifice (cardia ventriculi) 
 of the stomach, where it terminates opposite the loth thoracic vertebra. 
 In the neck it lies between the trachea and the vertebral column, resting 
 in part on the longus colli muscle; then inclining to the left side it reaches 
 the posterior mediastinum behind the left bronchus, and descends in that 
 mediastinum, at first in front of the thoracic duct, lower down to its left. 
 The (Esophagus is composed of 3 coats, as follows: 
 
 Muscular Coat (tunica muscularis), has longitudinal fibres externally, 
 circular fibres internally, which are continuous with the fibres of the 
 
THE ABDOMEN 323 
 
 stomach below, and with those of the inferior constrictor muscle 
 above. 
 Areolar Coat (tela submucosa), forms a loose connection between the 
 
 other two coats, and contains the cesophageal vessels. 
 Mucous Coat (tunica mucosa), in thick longitudinal folds, covered 
 with a layer of stratified pavement epithelium. The oesophagus is 
 loosely surrounded by an additional areolarcoat (tunica adventitia) 
 which loosely connects it to the surrounding structures. 
 (Esophageal Glands (glandulae cesophageas), are compound racemose 
 glands, situated in the submucous tissue throughout the tube, but most 
 numerous at the lower end, close to the cardiac orifice (cardia ventriculi) 
 of the stomach. 
 
 Arteries, are chiefly branches from the thoracic aorta. 
 Veins, empty into the vena azygos minor. 
 
 Nerves, are branches from the cesophageal plexus (plexus gullae), which is 
 formed by branches from the vagus and the cervical sympathetic. 
 
 THE ABDOMEN 
 
 The Abdomen is a large, oval-shaped cavity, situated between the 
 thorax above and the pelvis below, and bounded above, by the diaphragm; 
 below, by the brim of the pelvis; posteriorly, by the vertebral column, and 
 the fasciae covering the psoaeand quadrati lumborum muscles; anteriorly 
 and laterally, by the transversalis fascia, the lower ribs and the venter of the 
 ilium. It is invested internally by the Peritoneum, and it contains the 
 
 Stomach. Pancreas. Abdominal Aorta. 
 
 Intestines. Kidneys and Ureters. Inferior Vena Cava. 
 
 Liver. Supra-renal Capsules. Receptaculum Chyli. 
 
 Gall-bladder. Bladder (when distended). Thoracic Duct. 
 
 Spleen. Uterus (during pregnancy). Solar Plexus, etc. 
 
 Regions of the Abdomen (Regiones Abdominis). The abdomen is 
 divided into 9 regions by two horizontal planes, one at the level of the 
 cartilages of the loth ribs (sub-costal plane), another at the level of the 
 highest points of the crests of the ilia, and 2 vertical or lateral planes 
 from the cartilages of the 8th ribs to the centre of Poupart's inguinal liga- 
 ment. The 9 regions thus formed are named the 
 
 Right Hypochondriac. Epigastric. Left Hypochondriac. 
 
 Right Lumbar. Umbilical. Left Lumbar. 
 
 Right Inguinal or Iliac. Hypogastric. Left Inguinal or Iliac. 
 
324 HUMAN ANATOMY 
 
 Parts contained in each region are as follows: 
 
 Right Hypochondriac Region, contains the right lobe of the liver, 
 
 hepatic flexure of the colon, and part of the right kidney. 
 Epigastric Region, contains the right two-thirds of the stomach, left 
 
 lobe and part of the right lobe of the liver, gall-bladder, duodenum, 
 
 cceliac axis, solar plexus, pancreas, parts of the aorta, inferior vena 
 
 cava, vena azygos, and thoracic 
 
 duct, the supra-renal capsules and 
 
 parts of the kidneys. 
 Left Hypochondriac Region, con- 
 tains the fundus of the stomach, 
 
 spleen, tail of the pancreas, splenic 
 
 flexure of the colon, and part of 
 
 the left kidney. 
 Right Lumbar Region, contains the 
 
 ascending colon, lower half of 
 
 the right kidney, and part of the 
 
 small intestine. 
 Umbilical, contains the transverse 
 
 colon, transverse duodenum, part 
 
 of the great omentum and mesentery, and part of the small intestine. 
 Left Lumbar Region, contains the descending colon, lower half of the 
 
 left kidney, and part of the small intestine. 
 
 Right Inguinal or Iliac Region, contains the right ureter, caecum, ap- 
 pendix vermiformis, and the spermatic vessels of that side. 
 Hypogastric Region, contains convolutions of the small intestine, the 
 
 bladder in children and in adults when distended, and the uterus dur- 
 ing pregnancy. 
 Left Inguinal or Iliac Region, contains the left ureter and spermatic 
 
 vessels, and the sigmoid flexure of the colon. 
 
 Apertures in the Walls of the Abdomen are 8 in number, for the trans- 
 mission of structures to or from it, as follows: the 
 Opening for the Vena Cava (foramen venae cavae), in the diaphragm. 
 Aortic Opening (hiatus aorticus), behind the diaphragm, for the aorta, 
 
 vena azygos minor, thoracic duct, and occasionally the left sympathetic 
 
 nerve (see page 94). 
 (Esophageal Opening (hiatus cesophageus), in the diaphragm, for the 
 
 cesophagus, and the pneumogastric nerves (see page 94). 
 Umbilical Opening, in the anterior wall, transmitting the umbilical 
 
 vessels in the foetus, but obliterated after birth, leaving a puckered 
 
 depression, named the umbilicus. 
 
THE PERITONEUM 
 
 325 
 
 FIG. no. 
 
 Internal Abdominal Ring (annulus inguinalis abdominis), on each side, 
 half an inch above Poupart's ligament, for the passage of the sper- 
 matic cord in the male, and the round ligament of the uterus in the 
 female (see page 384). 
 
 Femoral or Crural Ring (annulus femoralis), on each side, just 
 below Poupart's inguinal ligament; for the passage of the femoral 
 vessels. This opening is closed by the crural or femoral septum 
 (see page 388). 
 
 THE PERITONEUM 
 
 The Peritoneum (peritonaeum) is a large serous membrane, which forms 
 in the male a closed sac, the parietal layer (peritonaeum parietale) of which 
 
 lines the abdominal walls, its 
 visceral layer (peritonaeum vis- 
 cerale) being reflected more or 
 less completely over all the 
 abdominal and pelvic viscera. 
 Its free surface is covered 
 with endothelium, and is 
 smooth, moist, and shining. 
 Its attached surface is con- 
 nected to the viscera and the 
 11 parietes of the abdomen by 
 the sub-peritoneal tela or 
 areolar tissue (tela subserosa). 
 In the female it is not a closed 
 sac, the free extremities of the 
 Fallopian tubes opening di- 
 rectly into its cavity. The 
 peritoneum is divided by a 
 constricted portion of its tis- 
 sue, at the foramen of Winslow 
 (foramen epiploicum) (9), 
 into 2 sacs, the 
 
 Greater Sac (cavum peri- 
 tonaei), extends over the 
 anterior two-thirds of the 
 liver (i), behind and 
 above the stomach (3); below, behind, and in front of the great 
 omentum, and below the meso-colon (12). 
 
 Lesser Sac (bursa omentalis) or Cavity of the Great Omentum, extends 
 behind and below the liver and stomach, above the meso-coion, 
 
326 HUMAN ANATOMY 
 
 within the great omentum, and behind the small or gastro-hepatic 
 omentum (ligamentum hepatogastricum) (2). 
 
 The Foramen of Winslow (foramen epiploicum) (9) is an opening which 
 connects the two peritoneal sacs with each other. It is formed by an hour- 
 glass constriction of the peritoneum caused by the hepatic artery in its 
 curved passage forward and upward from the coeliac axis to the transverse 
 fissure of the liver. It is situated behind the free border of the lesser 
 or gastro-hepatic omentum (ligamentum hepatogastricum) (2), immedi- 
 ately below the caudate lobe of the liver, and is bounded as follows: 
 
 Anteriorly, the lesser or gastro-hepatic omentum (ligamentum hepato- 
 gastricum) (2), containing the hepatic artery, portal vein, and the 
 ductus communis choledochus. 
 
 Posteriorly, the inferior vena cava, and the right crus of the diaphragm. 
 
 Superiorly, the caudate lobe (processus caudatus) of the liver. 
 
 Inferiorly, the duodenum, and the hepatic artery. 
 
 The Omenta are peritoneal folds which pass from the external surface 
 of the stomach (3) to various other organs, and are named the lesser or 
 gastro-hepatic, the great or gastro-colic, and the gastro- splenic omentum. 
 The "B.N.A." disregards this distinction and classes them with the 
 true ligaments. 
 
 Lesser or Gastro-hepatic Omenlum (ligamentum hepatogastricum) (2), 
 consists of two layers of peritoneum, the anterior layer belonging 
 to the greater sac (cavum peritonaei), the posterior to the lesser 
 sac (bursa omentalis). It ascends from the lesser curvature of the 
 stomach (3) to the transverse fissure of the liver (porta hepatis) 
 (i) and the end of the resophagus. Its right margin is free and 
 rounded, and contains between its layers the 
 
 Hepatic Artery and Portal Vein. Ductus Communis Choledochus. 
 Hepatic Plexus of Nerves. Lymphatics. 
 
 Great or Gastro-colic Omentum (omentum majus), consists of 4 layers of 
 peritoneum, the most anterior and superior of which belong to 
 the greater sac (cavum peritonaei), the two internal to the lesser sac 
 (bursa omentalis). The two anterior layers descend from the 
 stomach and spleen over the small intestines (6), and then ascend 
 as the posterior layers to enclose the transverse colon (4). 
 Castro-splenic Omentum (ligamentum gastrolienale), connects the 
 stomach with the spleen, and is continuous by its lower border with 
 the great omentum. It contains the vasa brevia vessels (aa. gastricae 
 breves). 
 
THE PERITONEUM 327 
 
 The Mesenteries (mesenteria) are folds of peritoneum connecting the 
 various parts of the intestinal canal (except the duodenum) to the posterior 
 abdominal wall. Each one contains the vessels of the part which it sup- 
 ports. They are the 
 
 Mesentery proper (mesenterium commune) (5), connects the convolu- 
 tions of the jejunum (6) and ileum to the posterior abdominal wall, 
 and contains between its layers the mesenteric vessels and nerves, 
 the lacteals, and the mesenteric glands. 
 
 Transverse Mesa-colon (mesocolon transversum) (12) connects the 
 transverse colon to the posterior abdominal wall, and is formed by 
 the two posterior layers of the great omentum (omentum ma jus). 
 
 Sigmoid Meso-colon (mesocolon sigmoideum), connects the sigmoid 
 flexure of the colon to the left iliac fossa. 
 
 Meso-rectum, connects the upper part of the rectum (14) to the front 
 of the sacrum, and contains the superior hemorrhoidal vessels. 
 
 Ligaments formed by the Peritoneum are 1 7 folds of peritoneum which 
 support certain organs, viz. 
 
 Castro-splenic (lig. gastrolienale), from the stomach to the spleen. 
 
 Hepatic (ligamenta hepatis), the longitudinal (lig. falciformehepatis), 
 coronary (lig. coronarium hepatis), and 2 lateral ligaments of the 
 liver (lig. triangulare dextrum et lig. triangulare sinistrum). 
 
 Splenic (lig. lienorenale), the suspensory ligament of the spleen. 
 
 Vesical, the false ligaments of the bladder, 5 in number. 
 
 Uterine, 2 vesico-uterine, 2 recto-uterine, and 2 lateral or broad liga- 
 ments of the uterus. 
 
 Pouches formed by the Peritoneum, as it passes over the rectum (14), 
 vagina, uterus (7) and bladder (8), are as follows: the 
 
 Recto-vesical Pouch (excavatio rectovesicalis), in the male, between the 
 
 rectum and the bladder. 
 Recto-vaginal or Douglas' Pouch (excavatio rectouterina or cavum 
 
 Douglasi), in the female, between the rectum and the posterior 
 
 vaginal wall. 
 Utero-vesical Pouch (excavatio vesicouterina), in the female, between 
 
 the anterior wall of the uterus and the posterior wall of the bladder. 
 
 Retro -peritoneal Fossae are recesses of the peritoneum, forming small 
 pouches in certain parts of the abdominal cavity; any one of which may be 
 the site of a retro-peritoneal hernia, and hernia of the vermiform appendix 
 (processus vermiformis) frequently occurs into one of the pericaecal 
 group. The lesser sac of the peritoneum may be regarded as a recess of 
 
328 HUMAN ANATOMY 
 
 peritoneum through the epiploic foramen of Winslow. The others are 
 divided into 3 groups, as follows : 
 
 Duodenal Fosses, 9 have been described, of which 3 are fairly constant, 
 viz.; the inferior, and superior,. both on the left side of the ascending 
 portion of the duodenum (n); and the duodeno-jejunal (recessus 
 duodenojejunalis), bounded above by the pancreas (10), below by 
 the left renal vein, to the right by the aorta (13), and to the left by the 
 left kidney. 
 
 Periccecal Fossa, are the ileo-colic (recessus ileocecalis anterior), in 
 front of the caecum; the ileo-cacal (recessus ileocecalis posterior), 
 behind the angle of junction of the ileum and caecum; and the sub- 
 ccBcal (recessus ileocecalis inferior), immediately behind the caecum. 
 Intersigmoid Fossa, lies behind the sigmoid meso-colon, and in front 
 of the parietal peritoneum, on the external iliac vessels. It is con- 
 stant in the foetus and during infancy, but disappears in a certain 
 percentage of cases as age advances. 
 
 ^Appendices Epiploica, are small pouches of peritoneum situated along 
 the colon and upper third of the rectum, and filled with fat. They 
 are chiefly found along the transverse colon. 
 Viscera invested by Peritoneum are the following-named: 
 Liver (i) (almost wholly). ' Transverse Colon (4). 
 
 Stomach (3) (almost wholly). Sigmoid Flexure. 
 Spleen. Rectum (upper ^). 
 
 Duodenum (n) (first part). Ovaries. 
 
 Small Intestine (6). Uterus (7). 
 
 Those partially invested by peritoneum are the 
 
 Duodenun (descending and Descending Colon. 
 
 transverse portions). Rectum (14) (middle third). 
 
 Ccecum. Vagina (upper part). 
 
 Ascending Colon. Bladder (8) (posterior wall). 
 
 Those having no peritoneal investment are the - 
 Pancreas (10). Kidneys. Supra-renal Capsules (glandulae 
 suprarenales) (see page 324). 
 
 THE STOMACH (VENTRICULUS) 
 
 The Stomach, the principal organ of digestion, is a dilated part of the 
 alimentary canal, situated between the termination of the oesophagus and 
 the beginning of the small intestine. It is somewhat pyriform in shape, 
 of musculo-membranous structure, about 12 inches long by 4 inches in 
 average diameter, held in position by the lesser omentum, and situated 
 diagonally across the upper abdomen, in the epigastric and left hypochon- 
 
THE STOMACH 
 
 329 
 
 driac regions, above the transverse colon, below the liver and diaphragm 
 It presents for examination a 
 Fundus or Upper End (c), connected to the spleen by the gastro- 
 
 splenic omentum (see under PERITONEUM). 
 
 Pyloric or Lower End, lies in contact with the anterior wall of the ab- 
 domen, the under surface of the liver, and the neck of the gall-bladder, 
 
 its position being near the 
 end of the cartilage of the 
 8th rib. 
 
 Greater Curvature (curvatura 
 ventriculi major) (d), is 
 convex and is connected 
 to the colon by the great 
 omentum. 
 
 Lesser Curvature (curvatura 
 ventriculi minor) (i), is 
 concave, and connected 
 to the liver by the lesser 
 omentum, and to the dia- 
 phragm by the gastro- 
 phrenic ligament. 
 
 (Esophageal Orifice (cardia) (b), is situated between the fundus and 
 the lesser curvature. It is funnel-shaped, and the highest part of 
 the organ. 
 
 Pyloric Orifice (pylorus) (k), opens into the duodenum (/), and is 
 guarded by the circular muscular fibres of the pylorus, which are ag- 
 gregated into a circular ring, projecting into the cavity, and with its 
 covering fold of mucous membrane, forming the Pyloric valve. 
 
 Structure of the Stomach. Its wall consists of 4 coats, the serous, 
 muscular, areolar, and mucous; together with vessels and nerves. The 
 
 Serous Coat (tunica serosa), is derived from the peritoneum, and covers 
 the whole external surface, excepting the points where the gastro- 
 splenic, great and lesser omenta are attached, and where the stomach 
 is in contact with the diaphragm. 
 
 Muscular Coat (tunica muscularis) (/), consists of longitudinal (stratum 
 longitudinale) external, circular (stratum circulare) middle, and 
 oblique (fibrae obliquae) internal. The longitudinal fibres radiate 
 from the cardiac orifice, are continuous with the longitudinal fibres 
 of the oesophagus and the small intestine, and are the most superficial. 
 The circular fibres lie deeper, form a layer over the whole organ, and 
 
330 HUMAN ANATOMY 
 
 are aggregated into a circular ring at the pyloric end, which, with its 
 lining mucous fold forms the pyloric valve. The oblique fibres lie 
 deepest, and are arranged in two sets around the cardiac end. 
 
 Areolar or Sub-mucous Coat (tela submucosa), consists of loose areolar 
 tissue, connecting the muscular and mucous coats, and contains the 
 gastric vessels. 
 
 Mucous Coat (tunica mucosa) (g), lined with columnar non-ciliated 
 epithelium, covered with polygonal alveoli, H 50 of an i ncn in diameter, 
 containing the orifices of the gastric glands. When the stomach is 
 contracted the mucous membrane lies in longitudinal folds or ruga 
 (h), one of which aids in forming the valve at the pyloric orifice. 
 
 Gastric Glands (glandular gastricae) are of 3 kinds, named pyloric, 
 cardiac and fundus glands, all tubular in character, and formed by a deli- 
 cate basement membrane, lined by epithelium. The 
 
 Pyloric Glands, are most numerous at the pyloric end; each consists of 
 2 or 3 short, closed tubes, opening into a common duct, the orifice 
 of which is situated at the bottom of an alveolus. They are lined with 
 columnar epithelium throughout. 
 
 Cardiac Glands, situated close to the cesophageal opening (cardia) of 
 the stomach, are tubules lined part way with columnar epithelium, 
 and filled with nucleated cells in their deepest parts. 
 
 Fundus Glands, are most numerous at the fundus and resemble the 
 pyloric glands. L"( cJc 
 
 Vessels and Nerves. The Arteries of the stomach are the gastric 
 (a. gastrica sinistra), the pyloric (a. gastrica dextra) and right gastro- 
 epiploic branches of the hepatic, the left gastro-epiploic and vasa brevia 
 from the splenic (a. lienalis). The 
 
 Veins, terminate either in the splenic (v. lienalis) and superior mes- 
 enteric veins, or directly in the portal vein. 
 
 Nerves, are terminal branches of the right and left pneumogastrics 
 (nn. vagi), and branches of the semilunar ganglia (ganglia coeliaca) 
 of the sympathetic, forming the gastric plexus (see page 241). 
 
 THE SMALL INTESTINE 
 
 The Small Intestine (intestinum tenue) is a convoluted, tubular, 
 digestive organ, about 20 feet in length, extending from the pylorus to 
 the ileo-caecal valve, where it terminates in the large intestine. It is 
 connected to the spinal column by the mesenteric portion of the perit- 
 oneum, and divided into 3 parts, the 
 
THE SMALL INTESTINE 
 
 331 
 
 FIG. 112. 
 
 Duodenum (d), about 10 inches long, the first part (pars superior) 
 ascends for 2% inches to the under surface of the liver and the neck 
 of the gall-bladder, the second part (pars descendens) descends for 
 3^ inches in front of the right kidney, and the third part (pars hori- 
 zontalis inferior) passes transversely for 4 inches to the left, across 
 
 the spinal column, to the left side 
 of the second lumbar vertebra, 
 where the superior mesenteric 
 artery crosses its junction with the 
 jejunum. The last inch of the 
 duodenum is described as the 
 fourth or ascending portion (pars 
 ascendens). The duodenum has 
 no mesentery, is partially covered 
 with peritoneum, and surrounds 
 the head of the pancreas. Into 
 its descending portion open the 
 ductus communis choledochus and 
 the pancreatic duct. 
 Jejunum (intestinum jejunum), 
 about two-fifths of the rest of the 
 small intestine, its coils lying 
 around the umbilical region. It is 
 named from the fact that it was 
 formerly supposed to be found 
 empty (jejunus} after death. 
 Ileum (intestinum ileum) (i), com- 
 prises the remainder of the small 
 intestine; is named from its twisted 
 course, lying below the umbilicus, 
 and terminating in the right iliac 
 fossa, at the ileo-cacal valve, or valve 
 of Bauhin. 
 
 Meeker s Diverticulum (diverticulum ilei), is a blind tube occasionally 
 found connected with the ileum, about 3^ feet above its termination; 
 it represents the remains of the vitelline duct of early foetal life. 
 
 Structure of the Small Intestine, is arranged in 4 coats, like that of the 
 stomach, a serous, muscular, areolar, and mucous coat. The 
 
 Serous Coat (tunica serosa), is derived from the peritoneum, which 
 partially invests the duodenum, and completely invests the jejunum 
 
332 HUMAN ANATOMY 
 
 and ileum, except for a small space along their mesenteric border, 
 where the vessels and nerves pass in. 
 
 Muscular Coat (tunica muscularis), consists of external longitudinal 
 
 (stratum longitudinale) and internal circular (stratum circulare) 
 
 fibres, the former being thinly distributed along the bowel, the latter 
 
 forming a thick layer, but not making complete rings. 
 
 Areolar Coat (tela submucosa), contains the vessels of the intestine, 
 
 and connects the muscular and mucous coats together. 
 Mucous Membrane (tunica mucosa), is covered with columnar non- 
 ciliated epithelium, and thrown into crescentic transverse folds, the 
 valvulce conniventes (plicae circulares), or valves of Kirkring. It pre- 
 sents also numerous vascular projections or Villi (villi intestinales), 
 simple follicles, and three kinds of glands (all described below). 
 Villi (villi intestinales) (/) are minute, vascular processes, which project 
 from the mucous membrane of the small intestine throughout its whole 
 extent, giving to its surface a velvety appear- 
 ance. They are most numerous in the duode- 
 num and jejunum, and altogether number 
 about 4 millions for the whole length of the 
 intestine. Each villus consists of a lacteal 
 vessel, a plexus of capillary blood-vessels, 
 epithelium, basement membrane, and mus- 
 cular tissue, supported and held together by 
 retiform lymphoid tissue. The 
 
 Lacteal Vessel, is situated in the axis of the 
 villus, and commences by dilated extrem- 
 ities near its summit. 
 Blood-vessels, form a plexus between the 
 
 lacteal and the basement membrane, enclosing the cells of the villus 
 in their interstices. 
 
 Basement Membrane, surrounds the preceding, and is made up of a 
 stratum of endothelial cells, upon which is a layer of columnar 
 epithelium. 
 
 Muscular Tissue, consists of longitudinal fibres prolonged into the vil- 
 lus from the muscular tissue of the mucosa. 
 
 Simple Follicles, or Crypts of Lieberkiihn (glandulae intestinales), are 
 minute, tubular depressions of the mucous membrane, opening be- 
 tween the villi, their orifices appearing as minute dots on the surface 
 of the mucous membrane. 
 
 Glands of the Small Intestine. The mucous membrane of the small 
 intestine contains the following glands: 
 
THE LARGE INTESTINES 333 
 
 Duodenal or Brunner's Glands (glandulae duodenales), are small, com- 
 pound glands, found only in the duodenum and the first part of the 
 jejunum, being most numerous near the pylorus. In structure they 
 are identical with the racemose glands of the mouth. 
 Solitary Glands (noduli lymphatici solitarii), are lymphoid organs, 
 situated throughout the intestine, though most numerous at the lower 
 portion of the ileum. They are agminated into some 20 or 30 oval 
 patches, named 
 
 Peyer's Patches or Glands (noduli lymphatici aggregati), on the sur- 
 face opposite to the mesenteric attachments, some of which are as 
 much as 4 inches in length. They are most numerous and largest in 
 the ileum, are few and small in the jejunum, and are occasionally seen 
 in the duodenum. 
 
 Vessels and Nerves. The Arteries of the jejunum and ileum are 
 branches of the superior mesenteric artery, forming an intricate plexus 
 in the areolar tissue, which gives off minute vessels to the glands and villi. 
 The duodenum is supplied by the pyloric (a. gastrica dextra) and pan- 
 creatico-duodenal branches of the hepatic, and the inferior pancreatico- 
 duodenal from the superior mesenteric. The 
 
 Veins, accompany the arteries and have a similar course and arrange- 
 ment. 
 Lymphatics, are in two sets, one for the mucous membrane and one 
 
 for the muscular coat. 
 
 Nerves, of the duodenum are derived from the solar plexus (plexus 
 cceliacus); those of the rest of the intestine from the sympathetic 
 plexuses around the superior mesenteric artery. 
 
 THE LARGE INTESTINE (INTESTINUM CRASSUM) 
 
 The Large Intestine (intestinum crassum) extends from the termination 
 of the ileum to the anus. It is about five feet long, of large calibre, and 
 consists of the same coats as the small intestine, the mucous being smooth 
 and without villi, the muscular having its longitudinal fibres collected into 
 3 narrow bands (taeniae coli) producing a sacculation (pouching) of its wall. 
 In its course it describes an arch around the convolutions of the small 
 intestine, and is divided into 3 portions, the Caecum, the Colon, and the 
 Rectum. 
 
 The Caecum (intestinum caecum) is a large blind pouch, about 2% inches 
 long and 3 inches broad, situated in the right iliac fossa, immediately 
 behind the abdominal wall, above the outer half of Poupart's ligament (liga- 
 mentum inguinale), and below the ileo-caecal valve, which opens into it. 
 
334 HUMAN ANATOMY 
 
 It lies free in the abdominal cavity, its closed end downward, its open end 
 upward and continuous with the commencement of the colon. It is usu- 
 ally enveloped entirely by peritoneum, and presents for examination the 
 Vermiform Appendix (processus vermiformis), a narrow, worm-like, 
 blind tube, averaging 3 inches in length, directed upward behind the 
 caecum, or to the left behind the ileum, or downward and inward into 
 the true pelvis. Its canal communicates with the caecum by an orifice 
 situated below and behind the ileo-caecal opening. Sometimes the 
 orifice of the vermiform process is partially guarded by a crescentic 
 fold of mucous membrane (valvula processus vermiformis) which is 
 produced on its upper border. Its proximal % is retained in 
 position by a triangular mesentery, its distal ^<j is free and com- 
 pletely covered by peritoneum. 
 
 Heo-ccBcal Valve, or Valve of Bauhin (valvula coli), guards the en- 
 trance of the small intestine, and is formed by two crescentic folds of 
 the mucous and cellular coats and circular muscular fibres (labium 
 superius et labium inferius) each fold being covered with villi on the 
 side toward the ileum, but smooth on the caecal side. 
 
 The Colon is divided into 4 parts, the ascending, transverse, and de- 
 scending colon and the sigmoid flexure. The Ascending Colon (colon 
 ascendens) (ac) extends from the caecum upward on the right side of the 
 abdominal cavity, to the under surface of the liver, where it turns to the 
 left, forming the hepatic flexure (flexura coli dextra). The Transverse 
 Colon (colon transversum) (tc) crosses the abdomen from right to left 
 to the lower end of the spleen, where it curves downward, forming the 
 splenic flexure (flexura coli sinistra). The Descending Colon (colon de- 
 scendens) (dc] passes downward along the outer border of the left kidney, 
 then inward along the outer border of the psoas muscle to the crest of the 
 ilium, where it terminates in the Sigmoid Flexure (colon sigmoideum) or 
 pelvic colon. The latter is curved like an /, first upward and forward, 
 then downward into a loop, which terminates in the rectum, opposite the 
 left sacro-iliac symphysis. The 
 
 Peritoneum, covers the transverse colon and the loop of the sigmoid 
 flexure almost completely, forming the transverse mesocolon and the 
 sigmoid mesocolon. It covers the ascending and descending colon 
 and the upper part of the sigmoid flexure on their anterior surface and 
 sides. 
 
 Mesocolon, is the mesentery of the colon, connecting the transverse por- 
 
 ' tion to the posterior abdominal wall in all cases; but exists for the 
 
 ascending colon in 26 per cent., and for the descending colon in 36 
 
THE LARGE INTESTINE 335 
 
 per cent, of the cases. The sigmoid mesocolon connects the loop of the 
 sigmoid flexure to the psoas fascia. 
 
 Phreno-colic Ligament, is a fold of peritoneum, connecting the com- 
 mencement of the descending colon with the diaphragm. 
 Appendices Epiploicce, are small pouches of peritoneum containing fat, 
 and found along the colon and part of the rectum. They are chiefly 
 appended to the transverse colon. 
 
 The Rectum (intestinum rectum) (r) is the terminal portion of the large 
 intestine, and extends from the sigmoid flexure (colon sigmoideum) or 
 pelvic colon to the anal orifice (a). It is about 8 inches long, not saccu- 
 lated, and, though not straight, is straighter than the rest of the gut. It 
 curves laterally to the middle of the sacrum, and backward about an inch 
 above its termination at the anus, where it forms an antero-posterior slit, 
 having its lateral walls in apposition, but capable of considerable disten- 
 tion. The relations of the rectum are as follows: 
 
 First Portion, 4 inches long, lies on the left pyriformis muscle and the 
 left sacral plexus of nerves; to its left are the left ureter and the 
 branches of the left internal iliac artery. 
 
 Second Portion, 3 inches long, in the male subject lies just behind the 
 trigonum vesicae and the vesiculae seminales, and close below the under 
 surface of the prostate gland. In the female it is adherent to the 
 central portion of the posterior wall of the vagina. 
 Third Portion or Anal Canal, i to i^ inch long, is surrounded by its 
 sphincters and the levator ani muscle, and is separated by the peri- 
 naeum from the membranous portion and bulb of the urethra in the 
 male, from the vagina in the female. 
 
 Peritoneum, invests the first portion almost completely, forming the 
 mesorectum, which connects it to the sacrum; invests the second por- 
 tion in front and laterally, and is thence reflected to the' bladder in the 
 male and to the vagina in the female. The third portion of the rectum 
 has no peritoneal investment. 
 Sphincters of the Rectum, are the internal sphincter and the sphincter 
 
 ani (see page 97). 
 
 Valves of Houston (plicae transversales recti), are 3 transverse folds of 
 the mucous lining, of semilunar shape, one in the upper part of the 
 rectum on the right side, another about the middle on the left side 
 and the third in front, opposite the base of the bladder. 
 Glands of the Large Intestine. The simple follicles are present through- 
 out its entire length, and are more numerous than in the small intestine. 
 The solitary glands (noduli lymphatici solitarii) are most abundant in the 
 
336 HUMAN ANATOMY 
 
 caecum and appendix, but are scattered irregularly over the entire canal. 
 Brunner's glands and villi are absent, the valvulae conniventes are almost 
 wanting. 
 
 Vessels and Nerves. The Arteries of the large intestine are the ileo- 
 colic, colica dextra and colica media from the superior mesenteric, to the 
 caecum, the ascending colon and the transverse colon; the colica sinistra 
 and sigmoid branches of the inferior mesenteric, to the descending colon 
 and the sigmoid flexure; the superior hemorrhoidal from the inferior mesen- 
 teric, the middle hemorrhoidal from the internal iliac, and the inferior 
 hemorrhoidal from the pudic (a. pudenda interna), to the rectum. The 
 Veins of the Rectum, commence in a plexus around the lower end, the 
 hemorrhoidal plexus, which gives off 6 vessels to unite into a trunk, 
 the superior hemorrhoidal vein. The plexus communicates also with 
 the tributaries of the middle and inferior hemorrhoidal veins, estab- 
 lishing a communication between the systemic and portal circulations. 
 Lymphatics, open into the mesenteric, lumbar, sacral and inguinal 
 
 glands, the latter receiving the vessels from around the anus. 
 Nerves, are derived from the sympathetic plexuses around the arteries 
 which are distributed to the large intestine. 
 
 THE LIVER (HEPAR) 
 
 The Liver is the largest gland in the body, weighing from 3 to 4 pounds, 
 and measuring all the way from 3 to 9 inches in various directions. It 
 is situated in the right hypochondriac, epigastric and part of the left hypo- 
 chondriac regions; has 5 fissures, 5 lobes, 5 ligaments, and 5 sets of vessels, 
 and is invested by peritoneum, except for a small space at the attachment 
 of the coronary ligament. It is also surrounded by a fibrous coat which 
 is continuous at the transverse fissure with the capsule of Glisson. Its 
 Upper Surface (facies superior), is convex, in relation with the under 
 surface of the diaphragm and lower 6 or 7 ribs, and is divided into 
 two lobes by the falciform ligament. 
 
 Under Surface (facies inferior) (Fig. 113), is concave, covers the stom- 
 ach, duodenum, hepatic flexure of colon (flexura colidextra), right 
 kidney and supra-renal capsule, and is divided into 5 lobes by 5 
 fissures. 
 
 Posterior Surface (facies posterior), direct backwards and is in con- 
 tact with the various structures forming the upper part of the poste- 
 rior abdominal wall. It is flat in the vertical axis but is deeply 
 indented by the vertebral column, and deeply grooved by the vena 
 
THE LIVER 337 
 
 Anterior Border (margo anterior), is sharp, and is notched in two places, 
 one at the fundus of the gall-bladder (vesica fellea), the other at the 
 round and falciform ligaments. It corresponds to the lower border 
 of the ribs and costal cartilages, descending a little lower during deep 
 inspiration and in the upright posture. 
 
 Posterior Border (margo posterior), rounded, and deeply grooved 
 (sometimes channeled) for the inferior vena cava (13). The anterior 
 and posterior borders, together form the inferior border (margo 
 inferior). 
 
 Fissures of the Liver are 5 in number, situated on the inferior and 
 posterior surfaces, and arranged in the form of the letter H. The left 
 limb of the H is the longitudinal fissure (fossa longitudinalis sinistra), 
 divided into the umbilical fissure (fossa venae umbilicalis) anteriorly, and 
 
 FIG. 114. 
 
 the fissure for the ductus venosus (fossa ductus venosi) (8) posteriorly; the 
 right limb is formed in front by the fissure (fossa vesicae felleae) for the 
 gall-bladder (9), behind by the fissure (fossa venae cavae) (12) for the vena 
 cava (13). The connecting bar of the H is the transverse fissure (porta 
 hepatis). The 
 
 Longitudinal Fissure (fossa longitudinalis sinistra), separates the left 
 lobe (lobus hepatis sinister) from the lobus Spigelii (lobus caudatus) 
 and the lobus quadratus. Its anterior portion, in front of the trans- 
 verse fissure (porta hepatis), is the umbilical fissure (fossa venae 
 umbilicalis), containing the umbilical vein in the foetus, and its 
 
33^ HUMAN ANATOMY 
 
 remains, the round ligament, in the adult. It is often bridged over 
 by a process of liver tissue, the pans hepatis. The posterior portion 
 is the fissure of the ductus venosus (fossa ductus venosi) (8), and lodges 
 the slender cord which, in the adult, represents that foetal vessel. 
 
 Transverse or Portal Fissure (porta hepatis), is about 2 inches long, 
 runs from the longitudinal fissure to the right, and transmits the por- 
 tal vein (7), hepatic artery (6) and nerves, and the hepatic duct (n) 
 and lymphatics. It separates the quadrate lobe in front from the 
 caudate (processus caudatus) and Spigelian (lobus caudatus) lobes 
 behind. 
 
 Fissure for the Gall-bladder (fossa vesicae felleae) (9), on the right of the 
 longitudinal fissure, and nearly parallel with it, extending from the 
 anterior border, backward to near the right end of the transverse 
 fissure. 
 
 Fissure for the Vena Cava (fossa venae cavae) (12), extends obliquely 
 upward on the posterior surface, and separates the Spigelian lobe 
 (lobus caudatus) from the right lobe (lobus hepatis dexter). Occa- 
 sionally this fissure is a complete canal in the substance of the liver. 
 
 Lobes of the Liver are 5 in number, but three are mere lobules of the 
 right lobe, formed by the smaller fissures. The 
 
 Right Lobe (lobus hepatis dexter) (2), is much the largest, and presents 
 the three small fissures and four shallow depressions, one anteriorly for 
 the colon, another posteriorly for the kidney, a third for the 
 duodenum, and a fourth for the supra-renal capsule (glandula 
 suprarenalis) . 
 
 Left Lobe (lobus hepatis sinister (i), is divided from the right lobe by 
 the longitudinal fissure (fossa longitudinalis sinistra), and rests upon 
 the stomach. 
 
 Quadrate Lobe (3), in front of the transverse fissure (porta hepatis) 
 and between the umbilical fissure (fossa venae umbilicalis) and that 
 (fossa vesicae felleae) for the gall-bladder. 
 
 Lobus Spigelii (lobus caudatus) (5), behind the transverse fissure 
 (porta hepatis), and between the fissure (fossa ductus venosi) for the 
 ductus venosus and that (fossae venae cavae) for the vena cava. 
 
 Caudate Lobe (processus caudatus) (4), a connecting ridge from the 
 lobus Spigelii (lobus caudatus) to the right lobe; it separates the 
 fissure for the vena cava (fossa venae cavae) from the fissure (fossa 
 vesicas felleae) for the gall-bladder, and lies directly above the foramen 
 of Winslow (foramen epiploicum). 
 
 Ligaments of the Liver are 5 in number, connecting the organ to the 
 
THE LIVER 339 
 
 under surface of the diaphragm and the anterior wall of the abdomen. 
 
 Four are folds of peritoneum; one, the round ligament, is the obliterated 
 
 umbilical vein of the foetus. The 
 
 Suspensory or Falciform Ligament (lig. falciforme hepatis), called also the 
 Broad and the Longitudinal Ligament, is a sickle-shaped double fold 
 reflected over the round ligament (lig. tereshepatis) andis attached to 
 the sheath of the right rectus muscle as low as the umbilicus, and to the 
 diaphragm. 
 
 Coronary Ligament (ligamentum coronarium hepatis), is a double fold, 
 containing firm areolar tissue in its interspace, and extending from the 
 posterior border of the liver to the diaphiagm. 
 
 Lateral Ligaments 2, are the triangular extremities of the coronary 
 ligament, and extend from the liver to the diaphragm. They are also 
 known as the lig. triangulare dextrum and the lig. triangulare sinis- 
 trum. 
 
 Round Ligament (lig. teres hepatis), ascends in the free margin of the 
 suspensory ligament (lig. falciforme hepatis) from the umbilicus to the 
 longitudinal fissure (fossa longitudinalis sinistra), in which it is con- 
 tinued to the vena cava. It results from the obliteration of the fcetal 
 umbilical vein, and is continued on the posterior surface as the oblit- 
 erated ductus venosus (8). 
 
 + tf STRUCTURE OF THE LIVER 
 
 The Liver Substance is composed of numerous lobules (lobuli hepatis) 
 held together by fine areolar tissue, and the ramifications of the hepatic 
 artery and veins, portal vein, hepatic ducts, lymphatics and nerves. The 
 whole organ is invested by a fibrous coat, and by a peritoneal coat for the 
 greater part of its surface. The 
 
 Fibrous Coat (capsula fibrosa [Glissoni]), is formed of connective tissue, 
 and is inflected at the transverse fissure (porta hepatis) along the ves- 
 sels, forming the so-called capsule of Glisson. 
 
 Peritoneal Coat (tunica serosa), is derived from the gastro-hepatic 
 (lesser) omentum, (ligamentum hepatogastricum) between the layers 
 of which the liver is received, and which forms 4 of its 5 ligaments. 
 Parts Uninvested by Peritoneum are on the anterior and superior sur- 
 faces, along the line between the two layers which form the suspensory 
 ligament; on the inferior surface, where the gall-bladder is attached, and 
 at the transverse fissure (porta hepatis) where the vessels enter; on the pos- 
 terior surface of the right lobe, a strip about 3 inches broad, where the liver 
 
340 
 
 HUMAN ANATOMY 
 
 is in contact with the diaphragm, also a part of the depression for the supra- 
 renal capsule (glandula suprarenalis). 
 
 The Lobules (lobuli hepatis) (i) are small, granular-looking bodies, of 
 polygonal shape, and about 3^o inch in diameter, clustered around the sub- 
 lobular branches of the hepatic veins, and connected together by con- 
 nective tissue (3), blood-vessels, ducts (2), and lymphatics. Each lobule 
 consists of a mass of hepatic cells, surrounded by a dense capillary plexus, 
 and contains the minute beginnings of a bile-duct, the so-called biliary 
 capillaries; possessing therefore all the essential constituents of a secreting 
 gland. A lobule contains 
 
 FIG. 115. 
 
 Hepatic Cells, each about Msoo inch in diameter, having a nucleus and 
 nucleolus, yellow coloring matter, glycogen granules, and oil globules. 
 Lobular Veins (3), forming a plexus in the lobule. \ , 
 Intralobular Vein (4), in the centre of each lobule. / 
 Plexuses, of lymphatics, nerves, and bile-ducts. 
 
 The Capsule of Glisson (capsula fibrosa) is the fibrous tissue which sur- 
 rounds the hepatic vessels in the transverse fissure (porta hepatis), and 
 accompanies them in their course throughout the substance of the liver. 
 It is continuous with the fibrous covering of the organ. The hepatic veins 
 and their tributaries are not invested by the capsule. 
 
 Nerves of the Liver are branches from the hepatic plexus, which is formed 
 by branches derived from the.cceliac plexus, the left pneumogastric (n. 
 vagus) and the right phrenic nerves. 
 
 
THE LIVER 
 
 341 
 
 FIG. 116. 
 
 VESSELS OF THE LIVER 
 
 Vessels of the Liver are 5 in number, the hepatic artery, portal vein, 
 hepatic veins, hepatic ducts (ductus hepaticus), and lymphatics, all 
 emerging in the transverse fissure except the hepatic veins, which enter the 
 fissure (fossa) for the vena cava. In the transverse fissure (porta hepatis) 
 all the vessels are enveloped in the capsule of Glisson, and the duct, artery 
 and vein are situated from before backward in the order named, repre- 
 sented by the letters D AV. Four of these vessels are described separately 
 below, the 
 
 Lymphatics, accompany the 
 blood-vessels in 2 sets, su- 
 perficial and deep; the latter 
 beginning in lymphatic 
 spaces around the capillaries 
 of the lobules, and accom- 
 panying the interlobular 
 vessels. They enter the 
 lumbar glands, the glands 
 of the lesser omentum, those 
 of the oesophagus and of the 
 lesser curvature of the 
 stomach. 
 
 The Hepatic Artery is the nu- 
 trient vessel of the liver; it arises 
 from the cceliac axis, gives off 
 pyloric, gastro-duodenal and 
 cystic branches, and passes up- 
 ward in front of the foramen of 
 Winslow to the transverse fissure, 
 
 where it divides into right and left branches, for the corresponding lobes 
 of the liver. These divide and subdivide, ramifying in the portal canals 
 throughout the organ, and giving off the following branches: 
 Vaginal Branches, to the capsule of Glisson. 
 Capsular Branches, to the fibrous covering of the liver. 
 Interlobular (rami arteriosi interlobulares), forming an arterial plexus 
 
 between the lobules. 
 Lobular, to the capillary network in the lobules. 
 
 The Portal Vein brings blood to the liver from the stomach, intestines, 
 pancreas and spleen; being formed by the union of the superior and infe- 
 
342 HUMAN ANATOMY 
 
 rior mesenteric, splenic and gastric veins, all the main veins of the abdomen 
 except the renal. It is about 4 inches long, enters the transverse fissure of 
 the liver, where it divides into the right and left portal veins, these dividing 
 into branches, which receive vaginal and capsular veins, and ramify 
 throughout the liver as portal canals (i), in company with the branches of 
 the hepatic artery and duct; finally breaking up into the 
 
 Inlerlobular Plexus (2), between the lobules, giving off the 
 
 Lobular Veins (3), converge to the centre of the lobule, and end in 
 the 
 
 Intralobular Vein (4), vertically in the centre of each lobule, enters the 
 sublobular of the hepatic veins below the lobule. 
 
 The Hepatic Veins convey blood away from the liver, and are con- 
 tinuations of the intralobular veins of the portal system, beginning as the 
 sublobular veins below each lobule, uniting finally into 3 trunks usually, 
 which enter the inferior vena cava in the fissure for that vessel. On sec- 
 tion of the liver the hepatic veins gape open, being adherent to the liver 
 substance; the portal veins are closed, being surrounded by the capsule of 
 Glisson. 
 
 The Hepatic Ducts carry away bile from the liver. They begin between 
 the cells of the lobules, in minute spaces, the bile-capillaries, forming 
 channels which radiate to the circumference of the lobule, and enter an 
 interlobular plexus between the lobules; from which plexus ducts pass into 
 the portal canals, are enclosed in the capsule of Glisson with the portal 
 vein and the hepatic artery, and join with other ducts to finally form 2 
 main trunks, which emerge at the transverse fissure, and by their union 
 form the Hepatic Duct (see below). 
 
 EXCRETORY APPARATUS OF THE LIVER 
 
 The Excretory Apparatus of the liver consists of the Hepatic Duct, 
 formed by the union of the two main trunks above-mentioned; the Gall- 
 bladder, a reservoir for the bile; the Cystic Duct, the duct of the gall-bladder; 
 and the Ductus Communis Choledochus or common bile-duct, formed by the 
 junction of the hepatic and cystic ducts. The 
 
 Hepatic Duct, about i % inches long; is formed in the transverse fissure 
 by the union of the two main biliary ducts, from the right and left 
 lobes. It joins the cystic duct from the gall-bladder to form the 
 Ductus Communis Choledochus, or Common Bile-duct, is a fibro-mus- 
 cular tube, covered by peritoneum and lined with mucous membrane, 
 about 3 inches in length, formed by the junction of the Cystic and 
 Hepatic ducts, and emptying its contents (bile) into the descending 
 
THE PANCREAS 343 
 
 part of the duodenum at a point about 3 inches from the pyloric 
 orifice of the stomach, generally in common with the duct of the 
 pancreas. 
 
 The Gall-bladder (vesica fellea) is a pear-shaped bag, 3 to 4 inches long, 
 an inch in greatest diameter, holding from 8 to 12 fluid drachms, invested 
 by peritoneum on its under surface and f undus, formed of a fibrormuscular 
 coat and lined by a mucous one, lying in a fissure on the under surface of 
 the liver, close to its anterior border, and directed obliquely downward, 
 forward, and to the right. Its 
 
 F undus (f undus vesicae felleae), touches the abdominal wall immedi- 
 ately below the gth costal cartilage, and is completely invested by 
 peritoneum. 
 Neck (collum vesicae felleae), is narrow and curves like the letter S; it 
 
 empties into the 
 
 Cystic Duct (ductus cysticus), about i^ inches long, is marked inte- 
 riorly by spirally arranged crescentic folds of its mucous lining, and 
 joins with the hepatic duct at an acute angle, to form the common 
 bile-duct (see above). 
 
 THE PANCREAS 
 
 The Pancreas is a compound racemose gland, about 5 finches long and 
 i^ inches broad, situated transversely across the posterior wall of the ab- 
 domen behind the stomach and in front of Jthe first lumbar vertebra. 
 Its structure resembles that of the salivary glands, being composed of red- 
 dish-yellow lobules, vessels and ducts, and ending in closed pouches sur- 
 rounded by a capillary plexus. 
 It is not enclosed in a capsule^ 
 but is surrounded by areolar 
 tissue, which extends into its 
 interior, and connects together 
 23 * the various lobules. Its 
 
 Head or Right Extremity 
 (caput pancreatis) (i), 
 
 shaped like the head of a hammer, lies in the concave curve of the 
 duodenum, in front of the common bile-duct, the inferior vena cava, 
 the left renal vein, the right crus of the diaphragm, and the aorta. 
 Neck (2), about an inch long, lies just below the pylorus, and above 
 
 the transverse portion of the duodenum. 
 
 Body (corpus pancreatis) (3), is in relation anteriorly with the ascend- 
 ing layer of the transverse meso-colon, the posterior wall of the stom- 
 
344 HUMAN ANATOMY 
 
 ach and the transverse colon; posteriorly with the aorta, splenic vein 
 (v. lienalis), origin of the superior mesenteric artery, crura of the 
 diaphragm, left kidney and supra-renal capsule, and the left quadratus 
 lumborum muscle. 
 
 gil (cauda pancreatis), or Left Extremity (4), lies above the left kidney 
 and in contact with the lower part of the inner surface of the spleen. 
 
 Pancreatic Duct, or Duct of Wirsung (5), extends the whole length of 
 the gland, commencing by the junction of the lobular ducts in the 
 tail, it receives the ducts of the various lobules, and opens into the 
 descending portion of the duodenum, about 3 or 4 inches below the 
 pylorus, usually by an orifice common to it and the common bile-duct, 
 occasionally by a separate orifice. Sometimes the pancreatic duct is 
 branched, in which case the upper branch is known as the duct of 
 Santorini (ductus pancreaticus accessorius). 
 
 '/,- -JK4223& are the ~ 
 
 Pancreatica Magna and Pancreaticae Parvae, from the splenic 
 
 (a. lienalis). 
 
 Pancreatico-duodenalis, branch of the hepatic artery, 
 inferior Pancreatico-duodenalis, branch of the sup. mesenteric. 
 Veins, open into the splenic and superior mesenteric veins. 
 Lymphatics, terminate in the lumbar glands. 
 Nerves, are filaments from the splenic plexus, which is a subdivision of 
 
 the cceliac plexus. 
 
 The Lesser Pancreas is a lobe of the head of the pancreas, sometimes 
 found detached, in which case it opens by a duct into the duodenum about 
 an inch above the orifice of the pancreatic duct. 
 
 DUCTLESS GLANDS 
 
 The Ductless Glands are those that discharge their special products 
 directly into the blood or lymphatic circulation. This is spoken of as 
 internal secretion, which, however, is not peculiar to this variety of gland, 
 since many of the other organs such as the liver, pancreas, stomach, in- 
 testine, kidney, prostate, testis, uterus, ovary, corpus luteum, and possibly 
 still other organs, form internal secretions in addition to their obvious 
 functions. The ductless glands are classified as belonging to the following 
 systems: 
 
 ^. Chromaphil system. 
 
 2. Cortical system. 
 
 3. Ductless glands of ento-dermal origin. 
 
 4. Ductless glands associated with the vascular system. 
 
 THE CHROMAPHIL (chromafnn or phaerochrome) SYSTEM includes those 
 glands which elaborate adrenin (laevo-adrenalin CgHisNOs of Aldrich) 
 
THE DUCTLESS GLANDS 345 
 
 They are so named because their cell cytoplasm contains granules which 
 are stained bright yellow to dark brown, by salts of chromium. In 
 this system are included the following: 
 
 1. Paraganglia which are small masses of chromaphil tissue associated 
 with the ganglia of the sympathetic nervous system. They may be 
 immediately on the outside, partially within, or entirely within the 
 capsules of the sympathetic ganglia. 
 
 2. Chromaphil Bodies of the Sympathetic Plexuses. These are asso- 
 ciated with the abdominal sympathetic plexuses; those of the aortic 
 plexus are called the -aortic bodies which are situated close to the origin 
 of the superior mesenteric artery. 
 
 3. Carotid Glands of Bodies (glomus carotica) are found, one on each 
 side, in or behind the bifurcation of the common carotid artery. 
 
 4. The Large Cells of the Anterior (buccal or glandular) lobe of the 
 pituitary body (hypophysis) (see page 186). 
 
 5. Medullary portions of the supra-renal glands (see page 363). 
 
 THE CORTICAL SYSTEM includes several masses of yellow glandular tissue 
 
 which is rich in lipoids, there are of these, 
 
 i'. Cortex of the Supra-renal Glands (see page 363). 
 
 2. Accessory Cortical Bodies which are several small masses of cortical 
 
 tissue found in relation to the testis and ovary. 
 DUCTLESS GLANDS OF ENTODERMAL ORIGIN include the following, 
 
 1 . Small Cells of the anterior (buccal or glandular) lobe of the Pituitary 
 Body (hypophysis) (see page 186). 
 
 2. Thyreoid Gland (glandula thyreoidea) is an incapsulated gland sur- 
 rounding the front and sides of the upper part of the trachea, and the 
 sides of the lower part of the larynx, under cover of the omo-hyoid, 
 sterno-hyoid and sterno-thyreoid muscles. 
 
 The Capsule consists of a superficial layer and a deep layer. The 
 superficial layer of the capsule is derived from the deep cervical 
 fascia. It is strongly attached to the trachea and the deep cervical 
 fascia. It is attached loosely by areolar tissue to the deep layer of 
 the capsule. The interval between the two layers is occupied by 
 numerous large blood-vessels, the veins in particular, forming a 
 very large anastomotic plexus. 
 
 The thyreoid gland itself usually consists of a right and a left lobe 
 the lower thirds of which are joined together across the mid-line 
 by the isthmus. Often there is an upward production of the upper 
 border of the isthmus forming a pyramidal lobe which is usually 
 to the left of the mid-line. Running from the lower border of the 
 hyoid bone to the apex of the pyramidal lobe is the hyo-thyreoid 
 
346 HUMAN ANATOMY 
 
 ligament which is sometimes muscular (m. levator glandulae thy- 
 reoidea); this, together with the attachments of the superficial 
 layer of the capsule to the trachea and deep cervical fascia, holds 
 the gland in place. 
 
 Deep Layer of the Capsule (tunica propria glandulae thyreoidea) is 
 intimately attached to the gland itself into the substance of which 
 it sends many supporting trabeculce and septa accompanied by 
 blood-vessels. 
 
 Structure, The gland is made up of many irregular masses called 
 lobules, each lobule consists of several closed vesicles which do not 
 communicate, each vesicle is lined with a single layer of cuboidal 
 or columnar cells, and filled with a yellowish viscous substance 
 called colloid. 
 
 Arteries are, the right and left superior thyreoid branches of the ex- 
 ternal carotid arteries, right and left inferior thyreoid branches of 
 the thyreoid axes of the subclavian arteries, and when present, the 
 thyreoidea ima branch either of the innominate artery or arch of 
 the aorta. 
 
 Veins are, right and left superior thyr eoid veins which empty into the 
 internal jugular veins, right and left middle thyreoid veins which, 
 when present, empty into the internal jugular veins, right and left 
 inferior thyreoid veins which empty into the innominate veins, 
 thyreoidea ima vein which when present empties into either the left 
 innominate vein or left inferior thyreoid vein. 
 
 Lymphatics on the left side empty into the upper loop of the thoracic 
 duct (ductus thoracicus), those of the right side empty into the 
 right lymphatic duct (ductus lymphaticus dexter). 
 
 The nerve supply is from the middle and inferior cervical ganglia of 
 the sympathetic. 
 
 3. Parathyreoid Glands, are small flattened ovoidal masses of a 
 yellow or reddish-brown color, they are slightly lighter in color 
 and of a softer consistency than the thyreoid gland itself. Each is 
 surrounded by its own individual capsule to which it is strongly 
 adherent. Each gland possesses a stalk formed by the blood- 
 vessels entering its hilus. The capsule sends many highly vascu- 
 lar supporting trabeculae and septa into the substance of the gland 
 which is composed of solid masses of polyhedral cells. There may 
 be a considerable variation in both the number and the disposi- 
 tion of these glands. Normally there should be an upper and a 
 lower pair. 
 
 Superior parathyreoids, a right and a left, are usually found, nearer 
 
THE DUCTLESS GLANDS 347 
 
 the mid-line than the lower pair, on the upper ends or on the dorsal 
 surface of the upper thirds of the lateral lobes of the thyreoid gland, 
 inside of and strongly adherent to its capsule; or they may be 
 imbedded in the areolar tissue between the two layers of the 
 capsule. 
 
 Inferior parathyreoids, a right and a left, usually lie on the dorsal or 
 lateral surface of the lower thirds of the lateral lobes of the thyreoid 
 gland, much further from the mid-line than the upper pair, and 
 more often outside of the capsule. Parathyreoids that have 
 wandered far from the thyreoid gland can hardly be identified 
 except under the microscope. 
 
 4. Thymus Gland (thymus), consists of two lateral lobes which 
 are firmly united, each being attached by a ligament to the lower 
 end of the lateral lobe of the thyreoid gland above it. The thymus 
 depends from these suspensory ligaments in the lower part of the 
 front of the neck downwards into the superior and anterior 
 mediastina, often reaching the pericardium. In front, it is in rela- 
 tion to the back of the sternum, the sterno-thyreoid and sterno- 
 mastoid muscles. Laterally it is in relation to the pleurae. Behind 
 it are the great blood-vessels which deeply groove its dorsal surface 
 although actually separated from it by the deep cervico-thoracic 
 fascia. The thymus is subject to much variation both in size and 
 shape, usually it is relatively largest at the age of puberty, becoming 
 progressively smaller thereafter. In color the thymus is reddish 
 gray, tending to become white or yellow as it undergoes involu- 
 tion. It is invested by a thin fibrous capsule which sends nu- 
 merous septa into the gland substance dividing it up into lobules 
 which in turn are divided up into follicles. Each follicle consists 
 of a central medulla which is partially surrounded by a cortex 
 which resembles lymphatic gland tissue. 
 
 Arteries are numerous, irregular branches of the internal mammary 
 and inferior thyreoid arteries. 
 
 Veins are numerous and irregular, they empty into the inferior 
 thyreoid, internal mammary, and left innominate veins. 
 
 Nerves are small branches of the vagus which run directly into the 
 gland, and minute branches of the cervical sympathetic which are 
 carried in on the arteries. 
 
 Lymphatics arise from plexuses around the follicles, pass through the 
 inter-lobular septa and the capsule to the adjacent lymph 
 glands. 
 
HUMAN ANATOMY 
 
 DUCTLESS GLANDS ASSOCIATED WITH THE VASCULAR 
 SYSTEM 
 
 i. The Spleen (lien) is a soft, brittle, highly vascular organ, of dark 
 purplish color, in size about 5 by 3 by i% inches, in weight about 7 ounces; 
 situated deeply in thejeft hypochondrium, between the fundus of the 
 stomach in front and internally, and the diaphragm behind and externally, 
 opposite the gth, zoth and nth ribs of thejeft side. It is connected with 
 the stomach, by the gastro-splenic amentum (ligamentum gastrolienale); 
 with the diaphragm, by the suspensory or phreno-splenic ligament; and 
 with the left kidney, by the lieno-renal ligament, all of which are folds of 
 peritoneum. Its 
 
 Outer. Surface (facies diaphragmatica), is convex, smooth, and in rela- 
 tion with the under surface of the diaphragm, 
 which separates it from the gth, loth and nth 
 ribs of the left side. 
 
 Inner Surface, is concave, and divisible into two 
 portions, one that is in contact, anteriorly (2) 
 with the posterior wall of the cardiac end of the 
 stomach and the tail of the pancreas (facies gas- 
 trica), the other portion being in contact posteri- 
 orly (i) with the left kidney (facies renalis). 
 Hilum (hilus lienis), a vertical fissure about the 
 middle of the inner surface, pierced by apertures 
 for the vessels and nerves. 
 Lower End, is flat and triangular (facies colica or basalis), and rests 
 
 upon the splenic flexure of the colon and the phreno-colic ligament. 
 Anterior Border (margo anterior) is between the gastric surface (facies 
 gastrica) and the diaphragmatic surface (facies diaphragmatica), it 
 is always notched. 
 
 Posterior Border (margo posterior) is between the diaphragmatic surface 
 (facies diaphragmatica) and renal surface (facies renalis). When it 
 is present, the basal surface (facies colica), at the lower end of the 
 spleen, is separated from the diaphragmatic surface (facies diaphrag- 
 matica) by the inferior border (margo inferior), from the gastric 
 surface (facies gastrica) by the anterior intermediate border (margo 
 intermedius anterior, and from the renal surface (facies renalis) by 
 the posterior intermediate border (margo intermedius posterior). 
 
 Structure of the Spleen. A fibre-elastic capsule, the tunica propria, 
 forms the framework of the spleen. It invests the organ externally, is 
 
STRUCTURES OF THE SPLEEN 349 
 
 reflected inward at the hilum along the vessels, and gives off from both 
 parts bands or trabeculce lienis, which traverse the organ in all directions 
 and unite with each other, to form a sponge-like structure, having numer- 
 ous primary spaces or areola, in which the pulp is contained. The splenic 
 pulp (pulpa lienis) looks like a soft, dark-red mass, resembling grumous 
 blood, but consists of branching connective-tissue corpuscles, the support- 
 ing susientacular or reticular cells, which form a delicate reticulated 
 tissue, making within the areolrc a number of secondary spaces, in which is 
 blood containing a large proportion of whiteblood-corpuscles, also red 
 blood-corpuscles in all stages of disintegration. These secondary spaces 
 are continuous with the terminal arterial capillaries and the primary 
 venous radicles, both of which open into them, bringing the blood supply 
 into relation with the pulp elements. The connective-tissue coat of the 
 arteries is converted into a lymphoid tissue in the arterioles, and this tissue 
 presents thickenings of spheroidal shape, the 
 
 Malpighian Bodies (noduli lymphatici lienalis), vary from Hoo to 
 ^5 inch in diameter, and are attached to the arterioles of the organ in 
 groups of 6 or 8. Their reticulum is slender and open, densely filled 
 with lymphoid cells (leukocytes and spleen phagocytes), and well 
 supplied with capillaries. 
 
 Peritoneal, or Serous Coat (tunica serosa), covers the whole organ, 
 except at the hilum and the attachments of the suspensory ligament 
 and the gastro-splenic omentum. 
 
 Splenic Artery (a. lienalis), is large and tortuous, and divides at the 
 hilum into 5 or 6 branches (4), each supplying a segment of the organ, 
 and terminating in capillaries which open into the secondary spaces. 
 Veins, arise by radicles from the secondary spaces, and anastomose 
 freely, joining to form 6 or more branches (5) which emerge from the 
 hilum and unite into the splenic vein (v. lienalis), the largest of the 
 constituents forming the portal vein. 
 
 Lymphatics, are superficial and deep; the two sets joining in the inte- 
 rior of the organ, pass through the lymphatic glands at the hilum, and 
 terminate in the thoracic duct. 
 
 Nerves, are branches of the splenic plexus (plexus lienalis), which is 
 formed by branches from the cceliac plexus, the left semilunar gan- 
 glion (ganglion coeliacum sinistrum), and the right pneumogastric 
 nerve (n. vagus dexter). 
 
 2. Coccygeal Gland or Body (glomus coccygeum) is a minute, highly 
 vascular, grayish-red, spherical body capping the terminations of the middle 
 sacral blood-vessels which form its stalk. It is situated in the mid-line 
 just beyond the tip of the coccyx, under cover of the coccygeal attachment 
 
350 HUMAN ANATOMY 
 
 of the sphincter ani muscle in the small triangular interval between the 
 levator ani muscles. It is invested by a fibrous capsule which sends septa 
 into its substance dividing it up into follicles or nodules. The follicles 
 are masses of epithelial cells none of which are susceptible of staining by 
 chromium salts. Each follicle is traversed by a blood space or sinus 
 which affords free intercommunication between the arteries and veins of 
 the gland. 
 
 Nerve supply is by many minute fibres from the sympathetic. It is 
 not uncommon to find several accessory coccygeal glands which in all es- 
 sentials resemble the principal gland. 
 
 3. Pineal Gland or Body (epiphysis or corpus pineale) while classed 
 as a ductless gland, is probably not functional in man (see page 194). 
 
 4. Lymphoglandulse, the lymph glands, hcemal lymph glands, and hcemal 
 glands are described under the lymphatic system (see page 172). 
 
 ORGANS OF VOICE AND RESPIRATION 
 
 THE LARYNX 
 
 .The Larynx is a musculo-membranous-cartilaginous box, the essential 
 organ of voice, placed at the upper end of the air-passage, between the 
 trachea and the base of the tongue, in the upper and fore part of the neck, 
 where it forms a projection in the middle line. Its cartilages are 9 in num- 
 ber, 3 single and 3 in pairs, the 
 
 Thyroid Cartilage (cartilage thyreoidea). ; 
 
 Cricoid Cartilage (cartilago cricoidea). 
 
 Epiglottis (cartilago epiglottica). 
 
 Arytenoid Cartilages 2 (cartilagines arytaenoideae). 
 
 Cuneiform Cartilages 2 (cartilagines cuneiformes). 
 
 Cornicula Laryngis 2 (cartilagines corniculatae). 
 
 The Thyroid Cartilage (cartilago thyreoidea), or shield-like cartilage, 
 consists of two Alee or wings (&), united in front at an acute angle, the 
 highest portion of its front being called the Pomum Adami, Adam's apple 
 (prominentia laryngea). Its 
 
 Outer Surface, affords attachment to the sterno- thyroid (m. sterno- 
 thyreoideus) thyro-hyoid (m. thyreo-hyoideus) and inferior con- 
 strictor muscles; the first two being attached along its oblique ridge. 
 Upper Border, is curved irregularly, has the thyroid notch (incisura 
 thyreoidea superior) (d) in front, and gives attachment to the thyro- 
 hyoid membrane. 
 
THE LARYNX 
 
 351 
 
 Lower Border, gives attachment to the crico-thyroid membrane in the 
 
 median line and on each side to the crico-thyroid muscle. 
 Inner Surface, gives attachment to the true and false vocal cords, the 
 epiglottis, thyro-arytenoid and thyro-epiglottidean muscles, and the 
 thyro-epiglottidean ligament. 
 
 Posterior Border, of each wing ends above and below in cornua (horns), 
 and gives attachment to the stylo- and palato-pharyngeus muscles. 
 
 Superior Cornu (cornu superius) (a) of each side 
 affords attachment to the thyro-hyoid ligament. 
 Inferior Cornu (cornu inferius) (c] of each side 
 articulates with the cricoid cartilage by a small 
 oval facet. 
 
 PIG. 119. 
 
 PIG. 1 20. 
 
 The Cricoid Cartilage (cartilago cricoidea), so 
 called from its ring-like shape, is situated below the 
 thyroid, with its narrow part to the front. It has 
 on each side 2 articular facets, one on the upper margin posteriorly for 
 the arytenoid cartilage, and one near the lower margin for the inferior 
 cornu of the thyroid cartilage. Its 
 
 Posterior Portion (lamina cartilaginis cricoideae), is deep and broad, 
 gives attachment in the middle line to the longi- 
 tudinal fibres of the oesophagus, and on each side to 
 the crico-arytenoideus posticus muscle (m. crico-ary- 
 taenoideus posterior). 
 
 Anterior Portion (arcus cartilaginis cricoideae), is 
 narrow and convex, and affords attachment to the 
 crico-thyroid muscles and part of the inferior con- 
 strictor. 
 
 Upper Border, affords attachment to the crico-thyroid membrane and 
 the crico-arytenoidei laterales muscles (mm. crico-arytaenoidei later- 
 ales), and articulates with the arytenoid cartilages. 
 Lower Border, is connected to the upper ring of the trachea by fibrous 
 
 membrane. 
 
 The Arytenoid Cartilages (cartilagines arytaenoideae), or pitcher-like 
 
 cartilages, are 2 in number, pyramidal-shaped, and situated on the upper 
 
 margin of the cricoid cartilage posteriorly, closing in the back of the 
 
 larynx. Each cartilage has 3 surfaces, 2 angles, a base and an apex. The 
 
 Anterior Surface, gives attachment to the plica ventricular is or false 
 
 vocal cord, and the thyro-arytenoideus muscle (m. thyreo-arytae- 
 
 noideus). 
 
 Anterior Angle, gives attachment to the plica vacates or true vocal 
 cord and the thyro-arytenoideus muscle (m. thyreo-arytaenoideus). 
 
352 
 
 HUMAN ANATOMY 
 
 PIG. 121. 
 
 Posterior Surface, has attached to it the arytaenoideus (m. arytae- 
 
 noideus). 
 Posterior Angle, gives attachment to the crico-arytenoideus lateralis 
 
 and posticus muscles (mm. crico-arytaenoidei laterales et posterior). 
 Internal Surfaces of each look toward each other. 
 Base, has a facet for articulation with the cricoid. 
 Apex, articulates with the corniculum laryngis. 
 The Cornicula Laryngis (cartilagines corniculatae) are 2 
 small cartilaginous nodules attached to the apices of the 
 arytenoid cartilages, and are also called the Cartilages of Santorini. To 
 them are attached the aryteno-epiglottidean folds (plicae arytaeno- 
 epiglotticae). 
 
 The Cuneiform Cartilages, or Cartilages of Wrisberg (cartilagines cunei- 
 formes), are 2 rods of yellow elastic cartilage contained in the free borders 
 of the aryteno-epiglottidean folds (plicaa arytaeno-epiglotticee) one on 
 each side, just in front of the arytenoid cartilages. 
 
 The Epiglottis (cartilage epiglottica) is a cartilaginous lid for the larynx. 
 It is leaf-shaped, situated behind the base of the tongue, and attached by 
 its apex to the posterior surface of the thyroid cartilage, just below the 
 median notch. Its 
 
 Base, is free, and curves over the base of 
 
 the tongue. 
 
 Apex, (petiolus epiglottidis), is connected 
 to the receding angle of the thyroid car- 
 tilage by the thyro-epiglottic ligament. 
 Anterior Surface, is attached to the hyoid 
 bone by the hyo-epiglottic ligament, and 
 to the tongue by 3 glosso-epiglottidean 
 folds (plicae glosso-epiglotticae). 
 Posterior Surface, covers the superior aper- 
 ture of the larynx when food passes 
 through the pharynx. 
 
 Lateral Margins, are connected to the ary- 
 tenoid cartilages by the aryteno-epiglotti- 
 dean folds (plicae arytaano-epiglotticse). 
 Ligaments of the Larynx are 20 in num- 
 ber, 8 Extrinsic Ligaments, connecting the larynx to the hyoid bone 
 (i), the tongue, and the trachea (15); and 12 Intrinsic Ligaments, bind- 
 ing its several cartilages together. The Extrinsic Ligaments 8 are the 
 Hyo-epiglottic Ligament, connecting the hyoid bone (i) with the 
 epiglottis (2), 
 
 FIG. 122. 
 
THE LARYNX 353 
 
 Glosso-epiglottic Folds three (plicae glosso-epiglotticae), from the tongue 
 
 to the epiglottis. 
 Thyro-hyoid Membrane (membranahyo-thyreoidea) (3), connecting the 
 
 thyroid cartilage (n) with the hyoid bone (i), and bounded laterally 
 
 by the two 
 Lateral Thyro-hyoid Ligaments (ligamenta hyo-thyreoidea laterales) 
 
 (6) each containing a nodule of cartilage, the cartilago triticea. 
 Crico-tracheal Ligament, from the cricoid cartilage (18) to the trachea. 
 Intrinsic Ligaments 12, are the 
 
 Thyro-epiglottic Ligament (ligamentum thyreo-epiglotticum), connect- 
 ing the thyroid cartilage (u) with the epiglottis (2). 
 Crico-thyroid Membrane (conus elasticus) (13), connecting the cricoid 
 
 (18) and thyroid (n) cartilages. 
 
 Crico-thyroid Capsular Ligaments 2, enclosing those articulations. 
 Crico-arytenoid Ligaments (ligamenta cricoarytaenoidea) 2, connect the 
 
 cricoid and arytenoid cartilages together. 
 
 Crico-arytenoid Capsular Ligaments 2, enclosing those articulations. 
 Superior Thyro-arytenoid or Thyreo-arytenoid Ligaments 2, in the false 
 
 vocal cords (plicae ventriculares) (5). 
 Inferior Thyro-arytenoid or Thyreo-arytanoid Ligaments 2, in the true 
 
 vocal cords (plicae vocales) (9). 
 
 Interior of the Larynx presents a cavity which is divided into two parts 
 by the inward projection of the true vocal cords. The superior part, 
 sometimes called the vestibule, is broad and triangular in shape; the inferior 
 part of the cavity is at first elliptical and lower down is circular, becoming 
 continuous with the tube of the trachea. The 
 
 Glottis or Rima Glottidis, is a narrow chink or interval between the 
 inferior vocal cords, formed by the projection into the cavity of the 
 larynx of these cords and the thyro-arytenoidei muscles. Its greatest 
 length is less than an inch, its greatest breadth about half an inch. Its 
 form is a narrow fissure of varying width. 
 
 Superior or False Vocal Cords (plicae ventriculares) (5), contain the 
 superior thyro-arytenoid ligaments, extend from the angle of the 
 thyroid cartilage around to the anterior surfaces of the arytenoids, and 
 consist of two folds of mucous membrane, each having a free cres- 
 centic margin. 
 
 Inferior or True Vocal Cords (plicae vocales) (9), contain the inferior 
 thyro-arytenoid ligaments, extend from the angle of the thyroid car- 
 tilage around to the anterior angles of the bases of the arytenoids, and 
 consist of two thin layers of mucous membrane covering the ligaments 
 23 
 
354 HUMAN ANATOMY 
 
 named, each having the thyro-arytenoideus muscle external and par 
 allel to it. 
 
 Ventricle of the Larynx (ventriculus laryngis) (7), is an oblong fossa 
 on each side of the larynx, between the true and false vocal cords, 
 leading up to the sacculus laryngis by a narrow opening. 
 
 Sacculus Laryngis (appendix ventricuke) or Laryngeal Pouch, is a 
 membranous sac, placed between the superior vocal cord and the 
 thyroid cartilage. It is of conical shape, and contains 60 or 70 small 
 mucous glands which secrete a fluid for the lubrication of the true 
 vocal cord. The sacculus is covered in by the aryteno-epiglottideus 
 inferior muscle internally, and by the thyro-epiglottideus externally, 
 both muscles compressing it to discharge its contents. The Sacculus 
 Laryngis is also called the Sinus of Morgagni, and the lower part of 
 the ventricle is sometimes named the Sac of Hilton. 
 
 Epithelium, is stratified squamous epithelium over the true vocal cords, 
 the upper part of the aryteno-epiglottidean folds, and the upper half 
 of the posterior surface of the epiglottis; over all the rest of the larynx, 
 the lining mucous membrane is covered by columnar ciliated cells. 
 
 Muscles of the Larynx are 8 in number, 5 of which are the muscles of 
 the vocal cords and rima glottidis, and 3 are connected with the epiglottis. 
 The former are the 
 
 Crico-thyroid (m. crico-thyreoideus). 
 
 Crico-arytenoideus Posticus (m. crico-arytaenoideus posterior). 
 
 Crico-arytenoideus Lateralis (m. crico-arytaenoideus lateralis). 
 
 Arytenoideus (m. arytaenoideus) . 
 
 Thyro-arytenoideus (m. thyreo-arytaenoideus). 
 
 Muscles of the Epiglottis are the 
 
 Thyro-epiglottideus (m. thyreo-epiglottideus). 
 Aryteno-epiglottideus (arytaeno-epiglottideus) Superior and Inferior. 
 
 These muscles are described at page 85. 
 
 Vessels of the Larynx. The Arteries are the Superior Laryngeal and 
 Crico-thyroid branches of the superior thyroid (a. thyreoidea Superior) 
 from the external carotid: and the Inferior Laryngeal Branch of the infe- 
 rior thyroid (a. thyreoidea inferior) from the thyroid axis (truncus thy- 
 reocervicalis). The 
 
 Veins, open into the internal jugular and the innominate vein. 
 
 Lymphatics, open into glands near the bifurcation of the common caro- 
 tid artery, and others in front of the crico-thyroid membrane. 
 
 Nerves of the Larynx are the Superior and Recurrent (inferior) Laryn- 
 geal branches of the pneumogastric (n. vagus), joined by filaments from the 
 spinal accessory (n. accessorius) and the sympathetic. The 
 
THE TRACHEA AND BRONCHI 355 
 
 Superior Laryngeal, is the nerve of sensation. It enters the larynx by a 
 hole" in the thyro-hyoid membrane, and supplies the mucous mem- 
 brane, and the crico-thyroid and arytenoideus muscles. It has the 
 following branches, namely 
 
 External Laryngeal. Internal Laryngeal. 
 
 Recurrent Laryngeal (n. laryngeus inferior), is the motor nerve. It 
 winds from before backwards, around the subclavian artery on the 
 right side, around the arch of the aorta on the left side, and is dis- 
 tributed to all the laryngeal muscles except the crico-thyroid and 
 arytenoideus giving off, in its course, cardiac, oesophageal, tracheal, 
 and pharyngeal filaments, and finally anastomosing with the superior 
 laryngeal nerve. 
 
 THE TRACHEA AND BRONCHI 
 
 The Trachea is a membrano-cartilaginous, cylindrical tube, about 4% 
 inches long, and % to i inch in diameter, beginning at the lower border 
 of the larynx, opposite the 6th cervical vertebra, and ending opposite the 
 upper border of the 5th thoracic, by its bifurcation into the two bronchi. 
 It is composed of a fibro-elastic membrane containing 16 to 20 imperfect 
 cartilaginous rings, connected by muscular fibres. It is lined with mucous 
 membrane covered with ciliated columnar epithelium, and furnished with 
 racemose glands, the tracheal glands. 
 
 Anteriorly, it is convex, and is covered from above downward by the 
 
 Isthmus of the Thyreoid Gland. Thymus Gland. 
 
 Inferior Thyreoid Veins. Arch of the Aorta. 
 
 Sterno-hyoid Muscle. Left Innominate Vein. 
 
 Sterno-Thyreoid Muscle. Innominate Artery. 
 
 Cervical Fascia. Left Carotid Artery. 
 
 Manubrium of the Sternum. Deep Cardiac Plexus. 
 
 Posteriorly, it is flat, and in relation with the oesophagus. 
 Laterally , it is in relation with the 
 
 Common Carotid Arteries. Recurrent or Inferior Laryngeal Nerves. 
 Thyreoid Gland, lateral lobes. Pleurae. 
 Inferior Thyreoid Arteries. Pneumogastric or Vagus Nerves. 
 The Bronchi are two tubes similar in formation to the trachea, extending 
 from its bifurcation into the lungs, where they divide and subdivide into 
 bronchial tubes (rami bronchiales), losing their rings at the 2d or 3d sub- 
 division, whence plates of cartilage extend in their walls to their minuter 
 ramifications. The 
 
356 HUMAN ANATOMY 
 
 Right Bronchus (bronchus dexter), the wider, and the more hori- 
 zontal, is about i inch long, has 6 to 8 rings, and divides into 2 main 
 divisions, the eparterial branch, to the upper lobe, given off above the 
 pulmonary artery, and the hyparterial branch, passing under the artery 
 to be divided into two branches, for the middle and lower lobes. The 
 right bronchus lies behind the vena cava superior and the right auricle 
 of the heart having the right pulmonary artery at first below, then 
 anterior to it, and the vena azygos major arching over it from behind 
 forward. 
 
 Left Bronchus, the narrower and more oblique, is nearly 2 inches long, 
 Has 9 to 12 rings, and divides into 3 main divisions (though its lung 
 has but 2 lobes). It passes beneath the arch of the aorta and in front 
 of its descending portion, also in front of the oesophagus and the tho- 
 racic duct, having the left pulmonary artery above and in front of it. 
 
 Vessels and Nerves. The Arteries are the Tracheal, branches of the 
 inferior thyreoid, from the thyreoid axis (truncus thyreocervicalis) ; and 
 the Bronchial, from the thoracic aorta. The 
 
 Veins, open into the thyreoid plexus and the bronchial veins. 
 
 Lymphatics, terminate in the mediastinal glands. 
 
 Nerves, are derived from the pneumogastric (n. vagus) and its recur- 
 rent or inferior laryngeal branch, also from the sympathetic. 
 
 THE PLEURA 
 
 The Pleurae are two delicate serous sacs, one surrounding each lung, 
 and reflected over the pericardium, the diaphragm, and the inner surface 
 of the thorax. The right sac is shorter, wider, and reaches higher into the 
 neck than the left. The two sacs meet for a short space behind the middle 
 of the sternum, at the approximation of the anterior borders of the lungs. 
 The 
 
 Pleura Pulmonalis, or Visceral Layer, covers the lung, and invests that 
 
 organ as far as its root. 
 Pleura Costalis, or Parietal Layer, lines the inner surface of the parie- 
 
 tes of the chest. 
 
 Cavity of the Pleura, is the space between the two layers. 
 Ligamentum Latum Pulmonis, or Broad Ligament of the Lung, is a 
 triangular fold or reflection of pleura, which descends from the root 
 of the lung posteriorly to the upper surface of the diaphragm. 
 The Mediastinum is the space between the two pleurae in the median 
 line of the thorax, extending from the sternum to the vertebral column, 
 and containing all the thoracic viscera except the lungs. The 
 
THE LUNGS 357 
 
 Superior Mediastinum, lies above the upper level of the pericardium 
 and contains the 
 
 Origins of the Sterno-hyoid and Sterno-thyreoid Muscles. 
 Longus Colli Muscles, their lower Pneumogastric Nerve (n. vagus). 
 
 ends. Cardiac and Phrenic Nerves. 
 
 Arch of the Aorta. Left Recurrent or Inferior Laryn- 
 
 Innominate Artery. geal Nerve. 
 
 Left Carotid Artery, in part. Trachea. 
 
 Left Subclavian Artery, in part. (Esophagus. 
 Superior Vena Cava, upper half. Thoracic Duct. 
 Innominate Veins. Thymus Gland. 
 
 Left Superior Intercostal Vein. Lymphatic Glands. 
 
 Anterior Mediastinum, between the sternum and the pericardium, con- 
 tains 
 
 Areolar Tissue. Branches of Internal Mammary Artery. 
 
 Triangularis Sterni Muscle. Lymphatic Vessels and Glands. 
 
 Middle Mediastinum, contains the 
 
 Heart and Pericardium. Bifurcation of the Trachea. 
 
 Ascending Aorta. Pulmonary Arteries and Veins. 
 
 Superior Vena Cava, lower half. Phrenic Nerves. Lymphatic Glands. 
 Posterior Mediastinum, contains the 
 
 Descending Aorta. (Esophagus. 
 
 Azygos Veins. Thoracic Duct. 
 
 Pneumogastric (nn. vagi) and Splanchnic Lymphatic Glands. 
 Nerves. 
 
 THE LUNGS (PULMONES) 
 
 The Lungs are the two essential organs of respiration contained in the 
 cavity of the thorax, where they are separated from each other by the 
 heart (i) and the other contents of the mediastinum. They are covered 
 by the pleurae, and are characterized by lightness (sp. gr. 0.345 to 0.746), 
 sponginess, elasticity, and crepitation when pressed. They weigh together 
 about 42 ounces, the right lung being the heavier by about 2 ounces. At 
 birth their color is a pinkish-white, becoming mottled as age advances by 
 slate-colored patches, from the deposit of carbonaceous granules in the 
 areolar tissue of the organ. The. Right Lung is the larger and has^3 lobes; 
 the Left Lung has 2 lobes. Each lung presents for examination an 
 
 Apex (apex pulmonis), situated in the neck, behind the interval be- 
 tween the two heads of the sterno-mastoid muscle, and rising about 
 
35 
 
 HUMAN ANATOMY 
 
 an inch above the clavicle. It is in relation with the subclavian artery 
 and the scaleni muscles. 
 
 Base (basis pulmonis), is broad, concave, and directed obliquely down- 
 ward and backward, resting on the upper convex surface of the dia- 
 phragm. 
 
 External Surface (facies costalis), is convex, smooth, marked by the 
 fissures, and corresponds in form to that of the thorax. 
 
 Inner Surface (facies mediastinalis), is concave, presents in front a 
 depression for the heart and behind a deep fissure, the hilum, which 
 gives attachment to the root of the lung. 
 
 FIG. 123. 
 
 Root (radix pulmonis), is where the bronchus (18), vessels (20), and 
 nerves enter the lung, bound together by areolar tissue. In front of 
 the root is the phrenic nerve, behind it the pneumogastric nerve (n. 
 vagus). Its chief structures are arranged in the following manner: 
 
 (Pulmonary veins. 
 Pulmonary artery. 
 
 From above downward, on 
 right side of body, 
 
 Bronchus, etc. 
 
 Bronchus (18), etc. 
 Pulmonary artery. 
 Pulmonary veins (20). 
 
 V. A. B. 
 
 B. A. V. 
 
THE LUNGS 
 
 359 
 
 From above downward, on 
 left side of body, 
 
 Pulmonary artery (7). 
 Bronchus (19), etc. 
 Pulmonary veins (20). 
 
 A. B. V. 
 
 FIG. 124. 
 
 Structure of the Lung. The lung has a serous coat (the pleura); a 
 sub-serous, elastic areolar tissue, investing the entire organ, and extending 
 
 inward between the lobules; and the 
 parenchyma, or true lung-tissue, com- 
 posed of 
 
 Lobules, each consisting of several 
 air-cells or compartments, arranged 
 around the termination of a bron- 
 chiole, and surrounded by 6 plexuses 
 of pulmonary and bronchial arteries 
 and veins, lymphatics and nerves. 
 Each lobule is a miniature lung, 
 pyramidal in form, with base out- 
 ward, and about ^f 2 inch in diam- 
 eter. Fig. 123 shows 2 lobules. 
 Alveoli, or Air-cells, are separated 
 from each other by thin septa, are 
 lined with pavement epithelium on 
 a basement membrane, and vary 
 in diameter from ^ O o to Ko inch. 
 
 Vessels and Nerves of the Lungs. The lungs are nourished by the 
 bronchial arteries, and supplied with blood for oxygenation by the pul- 
 monary arteries. 
 
 Bronchial Arteries, are derived from the thoracic aorta. 
 
 Bronchial Veins, open on the right side into the vena azygos major, 
 
 on the left side into the superior intercostal vein. 
 Pulmonary Arteries (5, 6, 7), are derived from the right heart. Their 
 
 terminal (lobular) branches do not anastomose with each other. 
 Pulmonary Veins (20), open by 4 large orifices into the left auricle of 
 the heart, carrying oxygenated blood from the lungs to the left heart. 
 The veins anastomose freely. 
 
 Lymphatics, terminate in the bronchial glands, at the root of the lung. 
 Nerves, are branches from the vagus and the sympathetic forming 
 the anterior and posterior pulmonary plexuses, from which filaments 
 are distributed to each lobule. 
 
360 HUMAN ANATOMY 
 
 THE URINARY ORGANS 
 THE KIDNEYS (RENES) 
 
 The Kidneys (renes) are two organs, situated in the back part of the 
 abdominal cavity, one on each side of the vertebral column, behind the 
 peritoneum, extending from the nth and i2th ribs to within 2 inches of 
 the crest of the ileum, the^ right kidney being a little lower than the left 
 one. Each kidney is about 4 inches by 2 by i, in the male adult weighs 
 from 4)^ to 6 oz.; and presents on its inner concave border the 
 
 U.ilum, a fissure leading into the sinus or cavity of the organ, and per- 
 mitting the passage of the vessels, nerves, and ureter, arranged in the 
 following order, from before backward, the renal vein, renal artery, 
 ureter, ^VAU. 
 
 Relations of the Kidneys. They are partially covered by peritoneum 
 on their anterior surface, but not at all posteriorly. They are surrounded 
 by a mass of fat and areolar tissue, and have the following relations: 
 Anterior Surface (facies renis anterior) of the Right Kidney, is in rela- 
 tion with the supra-renal gland, the right lobe of the liver, the de- 
 scending duodenum, and the ascending colon. 
 
 Anterior Surface of the Left Kidney, with the supra-renal gland, the 
 stomach, the tail of the pancreas, the descending colon, the jejunum, 
 and part of the spleen. 
 
 Posterior Surface (facies renis posterior), with the crus of the dia- 
 phragm, 1 2th rib and the transverse processes of the upper three 
 lumbar vertebrae, psoas magnus, quadiatus lumborum, and the apo- 
 neurosis of the transversalis muscle. 
 Upper Extremity (extremitas superior), is capped by the supra-renal 
 
 capsule (i). 
 Lower Extremity (extremitas inferior), extends to within 2 inches of 
 
 the crest of the ilium. 
 
 jGr.eneral Structure of the Kidney. A vertical section from its convex 
 to its concave border, shows it to consist of a central cavity QT sinuSj sur- 
 rounded except on one side by the kidney substance proper (parenchyma) . 
 The latter is divided into a cortical portion externally, and a medullary 
 portion internally, the medullary being arranged in pyramidal masses, 
 whose apices project into the central cavity. A dense, fibrous capsule 
 (tunica fibrosa) invests the organ, and is reflected inward at the hilum, 
 lining the sinus and forming sheaths for the vessels. It gives off an inter- 
 stitial stroma of connective tissue, which binds the vessels and tubes firmly 
 together throughout the substance of the kidney. The 
 
THE KIDNEY 361 
 
 Cynical Portion, consists of uriniferous tubules (tubuli renales). Mal- 
 pighian bodies (glomerula or renal corpuscles), blood-vessels, nerves, 
 lymphatics, connective tissue, and a granular matrix. It is of a red 
 p color, and is prolonged down between 
 
 the pyramids, to the sinus; the prolon- 
 gations being named columns of Berlin 
 (columnae renales) and the portions over 
 the bases of the pyramids are the cortical 
 arches. 
 
 Medullary .Substance (3), contains chiefly 
 the straight, collecting portion of the 
 uriniferous tubules, arranged in pyram- 
 idal masses, the pyramids of Malpighi 
 (pyramides renales), the apices of which 
 project into the sinus. 
 
 Sinus, receives the pelvis (6) of the ureter 
 (7), and is divided into 3 infundibula (5), 
 and they into 7 to 13 calices, into which 
 open the orifices of the uriniferous tubules, 
 1000 on each papilla or apex of a pyramid. 
 
 Minute Structure of the Kidney commences in the cortical substance 
 of the organ as the Malpighian bodies (corpuscula renis), small round 
 masses of deep-red color, averaging about K20 
 inch in diameter, and each consisting of a central 
 glomerulus of vessels and a membranous envelope 
 (capsula glomeruli) or Bowman's capsule, the 
 latter being the commencement of a uriniferous 
 tubule. The 
 
 Malpighian. Tuft, or vascular glomerulus, is a 
 network of convoluted capillary blood-vessels, 
 beginning by the afferent vessel and ending in 
 the eferent vessel, which are the respective 
 radicles of some of the branches of the renal 
 artery (a) and the renal vein (). The affer- 
 ent vessels are usually the larger. 
 Bowman's Capsule (capsula glomeruli) (c), 
 surrounding the glomerulus, is the dilated 
 
 extremity of a uriniferous tubule (d), and is lined on its inner surface 
 by a layer of j>quamous epithelial cells, on a delicate supporting 
 membrane, closely surrounding the convolutions of the glomerulus 
 and dipping in between them. 
 
362 HUMAN ANATOMY 
 
 The Tubuli Renales, or Uriniferous Tubules, begin at the capsule of 
 Bowman in the Malpighian bodies, and open into the sinus of the kidney 
 by orifices on the surface of the papillae. During their course they leave 
 the cortical portion, enter the medullary portion, return to the cortical 
 and again to the medullary, in which they continue to their termination. 
 In their course they become first convoluted, then spiral, then looped, 
 again spiral and convoluted, curved and finally straight; and have received 
 the following names: 
 
 Proximal Convoluted Tube, the first portion, below the neck at Bow- 
 man's capsule, in the cortical zone. Epithelium lining the tube is 
 polyhedral and of striated appearance. 
 Spiral Tube of Schachowa, in the cortical zone. Epithelium polyhedral 
 
 and striated. 
 
 Henle's Loop, in the medullary zone, consists of a descending limb, a 
 loop, and an ascending limb, the latter becoming spiral- as it ascends 
 into the cortical zone. Epithelium flat in the descending limb, poly- 
 hedral and striated in the ascending one. 
 
 Irregular Tubule, in the cortical zone. Epithelium angular and stri- 
 ated. 
 
 Distal Convoluted Tubule, in the cortical zone. Epithelium polyhedral. 
 Curved Tube, in the cortical zone. Epithelium varied, angular, 
 
 spindle-shaped, polyhedral. 
 
 Straight or Collecting Tube, partly in the cortical zone, descends 
 through the medullary portion and joins with others, forming the 
 pyramids of Fcrrein (apices outward) in the cortical zone, and the 
 pyramids of Malpighi (apices inward) in the medullary substance. 
 Epithelium more or less columnar. 
 
 Connective Tissue or Stroma, binds the tubules firmly together. 
 Arteries of the Kidney arise from the renal artery, a large branch of 
 the abdominal aorta. It divides into 4 or 5 branches, which enter the 
 kidney at the hilum (hilus renis), giving off small branches to the supra- 
 renal capsules, the ureter, etc. These again divide and end in the 
 Arteries Pro price Renales, the renal arteries proper, which enter the 
 kidney substance in the columns of Bertin (see page 360), form arterial 
 arches over the bases of the pyramids, and divide into ascending and 
 descending branches. The 
 
 Ascending or Interlobular Branches, pass to the capsule and end in the 
 capillary network of that part of the cortex, giving off in their course 
 the afferent vessels to the Malpighian tufts (see page 360). 
 Descending or Arteriolce Reclce, supply the medullary pyramids and 
 end at their apices in the venous plexuses there situated. 
 
 ' 
 
THE URETERS 363 
 
 Veins of the Kidney arise from 3 sources, the stellate veins beneath 
 t he i -upside of the organ, the venous radicles in the Malpighian tufts, and 
 the venous plexuses at the apices of the pyramids of Malpighi. Those 
 from the stellate plexuses on the surface of the kidney join together, form- 
 ing the 
 
 Interlobular Veins, which pass inward between the pyramids of Ferrein, 
 receive branches from the plexuses on the convoluted urinif erous tubes, 
 and join with the vence recta from the apices of the pyramids of Mal- 
 pighi, to form the 
 
 Vence Propice Renales, the renal veins proper, accompany the arteries 
 of the same name, receive the efferent vessels from the Malpighian 
 bodies adjacent, and join with corresponding veins in the sinus to 
 form the 
 
 Renal Vein, emerges at the hilum and opens into the Jnferior vena 
 cava; the left vein being longer than the right, having to cross in front 
 of the abdominal aorta. 
 
 Nerves of the Kidney are derived from the renal plexus, which is 
 formed by branches from the solar plexus (plexus cceliacum), the aortic 
 plexus, the semilunar ganglion, and the lessei and smallest splanchnic 
 nerves. They have small ganglia upon them, and communicate with the 
 spermatic plexus. 
 
 Lymphatics consist of a superficial and a deep set, and terminate in the 
 lumbar glands. 
 
 THE URETERS 
 
 The Ureter, the excretory duct of the kidney, is a musculo-membranous 
 tube, which conducts the urine from the kidney to the bladder. It com- 
 mences within the sinus of the kidney by 7 to 13 short tubes or calices, 
 which encircle the apices of the pyramids of Malpighi, and converge into 
 2 or 3 tubular divisions or infundibula, these by their junction forming the 
 pelvis or upper dilated extremity of the duct. The 
 
 Ureter Proper, begins at the lower end of its pelvis, is about 16 inches 
 long, and of the diameter of a small goose-quill. It descends, through 
 the lumbar region of the abdomen and the pelvic cavity, to the base 
 of the bladder, and opens into the cavity of that organ about 2 inches 
 from its fellow. 
 
 Course of the Ureter. In its course the ureter passes obliquely down- 
 ward and inward through the lumbar region, and downward, inward and 
 forward through the pelvic cavity, enters the posterior false ligament of 
 the bladder, passes obliquely between the muscular and mucous coats of 
 
364 HUMAN ANATOMY 
 
 that organ for nearly an inch, and ends by a constricted orifice at one of 
 the posterior angles of the trigone at the base of the bladder. 
 
 Relations of the Ureter. The junction of the renal pelvis and the 
 ureter proper is opposite the spinous process of the first lumbar vertebra, 
 about 2 inches from the middle line of the back. The ureter lies upon the 
 psoas muscle and behind the peritoneum; behind the ileum on the right 
 side and the sigmoid flexure of the colon on the left side. It crosses the 
 common or the external iliac artery; and is crossed by the spermatic vessels, 
 and the branches of the mesenteric arteries, also by the vas deferens in the 
 male. The right ureter lies close to the outer side of the inferior vena 
 cava. In the female the ureters pass along the sides of the neck of the 
 uterus and the upper part of the vagina, and beneath the root of the broad 
 ligament. 
 
 Structure of the Ureter. It is composed of 3 coats, fibrous, muscular, 
 and mucous. The fibrous coat (tunica adventitia) is continuous with the 
 capsule of the kidney and with the fibrous structure of the bladder. The 
 Muscular Coat (tunica muscularis), consists of longitudinal fibres ex- 
 ternally (stratum externum), and circular fibres internally (stratum 
 medium). A third layer (stratum internum), consisting of longi- 
 tudinal fibres, is found internal to the circular layer, in the neighbor- 
 hood of the bladder. 
 
 Mucous Coat, is prolonged over the papillae of the kidney, and is con- 
 tinuous with the mucous lining of the bladder. Its epithelium re- 
 sembles that of the bladder, and is known as' 'transitional epithelium, 
 consisting of 3 layers of cells, the innermost of which are quadrilateral 
 in shape. 
 
 Vessels and Nerves. The Arteries of the ureter are branches from the 
 renal, spermatic, internal iliac, and inferior vesical. The Nerves are de- 
 rived from the inferior mesenteric, spermatic, and pelvic plexuses. 
 
 THE SUPRA-RENAL GLANDS OR CAPSULES (GLANDULE 
 SUPRARENALES) 
 
 The Supra-renal Glands are properly classed with the ductless glands 
 of. the chromaphiL^and cortical systems (see page 344). They are two 
 small, yellowish bodies, situated one above each kidney, behind the perit- 
 oneum, and in the posterior portion of the abdomen. They vary in size 
 in different individuals, but are usually i^ inches long and wide, and from 
 2 to 3 lines in thickness. Each capsule has a small furrow, the hilum, on 
 its anterior surface, in which the vessels enter the organ, and in structure 
 consists of a 
 
THE BLADDER 365 
 
 Fibrous Capsule, which is very thin, closely adherent, and sends numer- 
 ous septa inward. 
 
 Cortical Substance, composed of columnar masses of polyhedral cells, 
 held together in layers by a fibrous stroma. 
 
 Medullary Substance, is darker than the cortical portion, and pulpy. 
 It consists of granular cells, supported by a delicate stroma, and 
 believed by some anatomists to be prolonged into the nerve fibres of 
 a very intricate plexus. 
 
 Relations of the Supra-renal Glands. Their surface is surrounded by 
 ireolar tissue containing much fat; their bases rest on the upper front 
 parts of the kidneys, theiVgpsterior surfaces on the crura of the diaphragm, 
 about the level of the loth thoracic vertebra. The 
 
 A nterior Surface, of the right gland is covered by the liver; that of the 
 Ic-ft one by the spleen and pancreas. 
 
 Superior Surface, of each is in relation internally with the great splanch- 
 nic nerve and semilunar ganglion. 
 
 Vessels and Nerves. The Arteries are the Supra-renal branches of the 
 aorta, renal, and phrenic arteries, forming a dense capillary plexus in the 
 cortical portion of the organ. 
 
 Veins, of each open into a single trunk, the Supra-renal Vein, which 
 on the right side of the body empties into the inferior vena cava, on 
 the left side into the left renal vein. 
 
 Lymphatics, open into the lumbar glands. 
 
 Nerves, are derived from the solar (cceliac) and renal plexuses, with 
 some filaments from the phrenic and vagus nerves, forming a compli- 
 cated network in the medullary substance of the organ, and having 
 numerous small ganglia developed upon them. 
 
 THE BLADDER (VESICA URINARIA) 
 
 The Bladder, the reservoir for the urine, is a musculo-membranous sac, 
 situated in the anterior portion of the pelvis, behind the. pubes, and in 
 front of the rectum in the male, in front of the cervix uteri and Vagina in 
 the female. When empty and contracted, or when slightly distended, it is 
 contained in the pelvic cavity; when greatly distended it is ovoid in shape, 
 and rises into the abdominal cavity, often extending nearly as high as the 
 umbilicus. When moderately distended it measures about 5 by 3 inches, 
 and holds about a pint. The 
 
 Summit, is connected to the umbilicus by the urachus (ligamentum 
 umbilicale medium) and the obliterated hypogastric arteries (liga- 
 
366 
 
 HUMAN ANATOMY 
 
 FIG. 127. 
 
 menta umbilicales laterales) of the foetus, forming three fibrous cords, 
 the Superior Ligament of the bladder. 
 
 Superior or Abdominal Surface, is free, and is covered by peritoneum. 
 
 Anterior or Pubic Surface, is partly covered by peritoneum above, and 
 is in relation below with the internal obturator muscles, the recto- 
 vesical fascia, and the anterior true ligaments of the bladder. 
 
 Posterior Surface, is covered by peritoneum, and is in relation with the 
 rectum in the male, with the uterus and upper part of the vagina in 
 the female. 
 
 Lateral Surfaces, are partly covered by peritoneum behind and above; 
 each is crossed obliquely by the obliterated hypogastric artery and the 
 vas deferens (c), the first passing from 
 below forward, the latter from below 
 backward. 
 
 Fundus or Base, is partly covered by 
 peritoneum, and rests on the second 
 portion of the rectum in the male, on 
 the lower part of the cervix uteri and 
 adherent to the anterior wall of the 
 vagina in the female. 
 
 Cervix or Neck, is constricted and contin- 
 uous with the urethra (f). It is sur- 
 rounded in the male by the prostate 
 gland (h), and is directed downward 
 and forward. 
 
 Ligaments of the Bladder are 10 in num- 
 ber, of which 5 are true ligaments, and 5 
 formed by folds of peritoneum. The true ligaments are the 
 
 Anterior or Pubo-prostatic, 2, are formed by the recto-vesical fascia, 
 and extend from the neck of the bladder, over the prostate gland, to 
 the back of the pubic bone. 
 
 Lateral, 2, also formed by the recto-vesical fascia, are attached to the 
 sides of the base of the bladder, and the prostate gland. 
 
 Urachus, the superior ligament (ligamentum umbilicale medium), 
 connects the summit of the bladder with the umbilicus. It is the 
 obliterated remains of a canal, which in the embryo connects the 
 bladder with the allantois and is situated between the two obliter- 
 ated hypogastric arteries (ligamenta umbilicales laterales). 
 False Ligaments, folds of peritoneum, are the 
 
 Posterior False Ligaments (plicae vesico-uterinae) female, (plicae recto- 
 vesicalis) male, 2, pass from the postero-lateral parts of the bladder. 
 
 are false ligaments, being 
 
THE BLADDER 367 
 
 to the sides of the rectum in the male, to the sides of the uterus in 
 the female. 
 
 Lateral False Ligaments (plicae umbilical es laterales), 2, from the 
 iliac fossae and lateral walls of the pelvis to the sides of the bladder. 
 
 Superior, or Suspensory Ligament (plica umbilicalis media), from the 
 summit of the bladder to the umbilicus, being peritoneum carried 
 off from the bladder by the urachus and the obliterated hypogastric 
 arteries. 
 
 Interior of the Bladder is lined by mucous membrane, which forms 
 folds or ruga when the viscus is empty, being loosely connected to the 
 muscular coat, except at the trigone and the uvula, where it is closely ad- 
 herent. The floor of the bladder presents the 
 
 Trigonum Vesica, or Vesical Trigone (i, Fig. 127), a pale-colored, tri- 
 angular space, extending from the urethral opening in front to a line 
 connecting the orifices of the ureters behind; and characterized by its 
 smooth surface and the intimate adhesion between its mucous and 
 muscular coats. 
 
 Uvula Vesicce (3, Fig. 127), is a small elevation of mucous membrane 
 projecting from the floor of the bladder into the urethral orifice. It is 
 said to be lifted by the anterior fibres of the levator ani muscle. 
 
 Orifices of the Ureters (2, Fig. 127), about 2 inches apart, at the base of 
 the trigone, and i ^ inches from the urethral opening. 
 
 Structure of the Bladder. The bladder has 4 coats, serous or perit- 
 oneal, muscular, sub-mucous, and mucous. The peritoneal coat is a 
 partial one, investing only the superior and posterior surfaces, and the 
 upper portion of the lateral surfaces. The 
 
 Muscular Coat, consists of unstriped muscular fibres, arranged in 3 
 layers; an external layer, chiefly longitudinal, the so-called detrusor 
 urines muscle; a middle layer, mostly circular, and forming a sphincter 
 vesicfg around the neck; and an internal layer, chiefly longitudinal. 
 
 Muscles of the Ureters, are two bands of oblique fibres, extending from 
 behind the orifices of the ureters to the middle lobe of the prostate 
 gland. 
 
 Sub-mucous Coat, is a layer of areolar tissue, connecting the muscular 
 with the mucous coat. 
 
 Mucous Coat, is thin, smooth, of a pale rose color, and is continuous 
 with the lining membrane of the ureters and the urethra. Its epithe- 
 lium is of the transitional variety, consisting of an inner layer of poly- 
 hedral, flattened, nucleated cells; beneath which are two layers of 
 club-shaped and spindle-shaped cells, wedged together. It contains 
 no mucous glands. 
 
368 HUMAN ANATOMY 
 
 Vessels and Nerves. The Arteries of the bladder are the superior 
 middle, and inferior Vesical in the male, with additional branches from the 
 uterine and vaginal in the female; all from the anterior trunk of the internal 
 iliac. The 
 
 Veins, form a plexus around the neck, sides, and base of the bladder, 
 
 and terminate in the internal iliac vein. 
 Lymphatics, terminate in the internal iliac glands. 
 Nerves, are derived from the pelvic plexus to the upper part of the 
 organ, from the 3d and 4th sacral nerves to its base and neck. 
 
 THE MALE URETHRA 
 
 The Urethra is the urinary canal from the neck of the bladder to the 
 meat us urinarius; in the male it is chiefly within the penis, is from 8 to 9 
 inches in length, and is divided into three parts, the pr astatic, membranous, 
 and spongy portions of the urethra. 
 
 The Prostatic Portion (pars prostatica) of the Urethra is that part of the 
 canal which pierces the prostate gland (4), is about i finches in length, of 
 spindle shape, and the widest and most dilatable part of the urethra. Its 
 floor presents the 
 
 Verumontanum, or Caput Gallinaginis (colliculus seminalis) (6), an 
 
 elevation of the mucous membrane (crista urethralis) and its adjacent 
 
 tissue, Y inch long, and supposed to contain muscular and erectile 
 
 tissue. 
 
 Prostatic Sinus (7), one on each side of the verumontanum, containing 
 
 the orifices of the prostatic ducts. 
 
 Sinus Pocularis, or Uterus Masculinus (utriculus prostaticus) (5), is a 
 
 small cul-de-sac situated at the front part of the verumontanum. 
 
 It extends for ^ inch upward and backward into the prostate gland 
 
 beneath its middle lobe. 
 
 Orifices of the Ejaculatory Ducts (8), open on the margins of the sinus 
 
 pocularis. 
 
 The Membranous Portion (pars membranacea) (9) is % inch long above, 
 and Yz inch along its floor, being that part of the canal lying between the 
 superior and inferior layers of the triangular ligament of the perinaeum. 
 Its walls are very thin, and almost destitute of erectile tissue. It is 
 surrounded by the deep transversus perinei or compressor urethras muscle, 
 and except the orifice, is the narrowest part of the urethral canal. On 
 its sides are the 
 
 Ducts of Cowper's Bulbo-urethral Glands (n), on their way to open 
 into the bulb of the urethra. 
 
THE URETHRA 
 
 369 
 
 FIG. 128. 
 
 The Cavernous or Spongy Portion (pars cavernosa) (16) is about 6 
 inches long, and has two dilatations, one at each end, named respectively 
 the Bulb and the Fossa Navicularis. The 
 
 Bulb' of the Urethra (13), is the upper end of the cavernous portion, 
 projects backward for Y inch, and contains the orifices (15) of the 
 
 ducts of the bulbo-urethral 
 or Cowper's glands. 
 Fossa Navicularis, is the lower 
 dilatation of the urethra, 
 and is situated within the 
 glans penis. 
 
 Lacuna Magna (lacuna ure- 
 thralis of Morgagni), the 
 largest of several orifices of 
 mucous follicles, situated on 
 the roof of the fossa navicu- 
 laris. 
 
 Glands of Littre (glandulae ure- 
 thrales), are numerous mu- 
 cous glands and follicles, 
 opening into the urethral 
 canal, their orifices being 
 directed forwards. 
 Meatus Urinarius, the exter- 
 nal orifice; is the most con- 
 tracted portion of the ure- 
 thra, and presents a vertical 
 slit, about 3 lines long, 
 bounded laterally by two 
 small labia. 
 
 Structure of the Urethra. It is 
 composed of a continuous mucous 
 membrane, continuous with the 
 mucous lining of the bladder, 
 ureters, and kidneys, and pro- 
 longed into the ducts opening into the urethra. The mucous membrane 
 is supported by a submucous tissue, which connects it with the various 
 structures through which it passes. The 
 
 Submucous Tissue, consists of a vascular erectile layer, outside which is 
 
 a circular layer of unstriped muscular fibres. 
 
 Voluntary Muscles of the Urethra, are the deep transversus perinei or 
 24 . 
 
37O HUMAN ANATOMY 
 
 compressor urethrae and the bulbo-cavernosus or accelerator urinae, 
 described on page 98. 
 
 Epithelium, is of the columnar variety, except near the meatus where it 
 is squamous. 
 
 THE FEMALE URETHRA 
 
 The Urethra in the female is only about i ^ inches long, imbedded in the 
 anterior wall of the vagina, perforating the triangular ligament, and sur- 
 rounded by fibres of the deep transversus perinei or compressor urethras 
 muscle. Its diameter is about % inch, but it is capable of considerable 
 dilatation, being surrounded by softer structures than are those around 
 the male urethra. The 
 
 Meatus Urinarius, is situated directly in front of the vaginal opening 
 and about an inch behind the glans clitoridis. 
 
 ORGANS OF GENERATION 
 
 THE MALE ORGANS OF GENERATION 
 THE URETHRAL GLANDS 
 
 The Prostate Gland (prostata) is a musculo-glandular organ, which 
 surrounds the neck of the male bladder and the beginning of the male 
 urethra. It is situated in the pelvic cavity, behind the lower part of the 
 symphysis pubis, and above the deep layer of the triangular ligament, its 
 posterior surface resting on the rectum. It is perforated by the urethra 
 and the common seminal ducts, but its own ducts open into the prostatic 
 portion of the urethra. It measures about i% inches by i)^ inches by i 
 inch, weighs about % oz., resembles a horse-chestnut in size and shape, 
 and consists of three lobes, two being lateral and of equal size, the third or 
 middle lobe being a small prominence situated in the notch between the 
 lateral lobes. Its 
 
 Position, is maintained by the anterior or pubo-prostatic ligaments of 
 the bladder, the deep layer of the triangular ligament, and the anterior 
 portions of the levator ani muscles. 
 
 Structure, is glandular substance arranged in follicular pouches, and 
 
 dense muscular tissue, the whole being invested by a firm fibrous 
 
 capsule, which gives off thin trabeculae into the substance of the gland. 
 
 Ducts, are 1 2 to 20 in number, lined by columnar epithelium, and open 
 
 on the floor of the prostatic portion of the urethra. 
 Arteries, are derived from the internal pudic, vesical and haemorrhoidai 
 arteries. 
 
THE PENIS 371 
 
 Veins, terminate in the internal iliac vein. 
 Nerves, are branches from the pelvic or hypo-gastric plexus. 
 Cowper's Glands (glandulae bulbo-urethrales) are two small, rounded 
 bodies, about the size of peas, situated between the two layers of the 
 triangular ligament, one on each side of the membranous portion of the 
 urethra, close above the bulb, and enclosed by the transverse fibres of the 
 compressor urethrae muscle. The 
 
 Excretory Duct, of each gland opens by a minute orifice on the floor 
 of the bulbous part of the cavernous portion of the urethra, after tra- 
 versing the wall of the urethra for about i inch, beneath its mucous 
 coat. 
 
 THE PENIS 
 
 The Penis is composed of a mass of erectile tissue enclosed in three 
 cylindrical compartments, each surrounded by a fibrous sheath which is 
 prolonged inward, forming numerous bands or trabeculae, which divide 
 the compartments into a number of spaces. The compartments are the 
 two corpora cavernosa and the corpus spongiosum (corpus 5 cavernosum 
 urethrae) (6), the latter lying between and beneath the former, like the 
 ramrod of a double-barreled gun. The 
 
 Erectile Tissue, is lodged in the interspaces between the trabeculae of 
 the fibrous structure, and consists of an intricate venous plexus, 
 supplied by afferent arteries and emptied by efferent veins. 
 The Corpora Cavernosa lie side by side, forming the upper and lateral 
 parts of the penis. They are joined together along their anterior three- 
 fourths, their posterior one-fourth forming the 
 Crura, which arise from the tuberosities of the 
 ischia and their rami, and meet beneath the sym- 
 physis pubis, forming two grooves, one above 
 for the dorsal vessels (i), and nerves (3), the in- 
 ferior one for the corpus spongiosum (6). 
 
 Suspensory Ligament (lig. suspensorium penis), 
 a fibrous membrane which connects the 
 root of the organ to the symphysis pubis. 
 Septum Pectiniforme (5), is the front portion 
 of the fibrous septum between the corpora cavernosa. This septum 
 extends but two-thirds along the penis, and is wanting for its anterior 
 third. 
 
 The Corpus Spongiosum (corpus cavernosum urethras) (6) is an erectile 
 tube lying in the inferior groove between the two corpora cavernosa, 
 having within it the urethra, and expanded at both ends to form the glans 
 
372 HUMAN ANATOMY 
 
 penis and the bulb. It is composed of trabecular (band-like) structure, 
 derived from a fibrous sheath, and containing erectile tissue. The 
 Bulb of the Corpus Spongiosum (bulbus urethras), receives the urethra 
 
 and is surrounded by the (bulbo-cavernosus) or accelerator urinas 
 
 muscle. 
 Glans Penis, is the external expansion of the corpus spongiosum 
 
 (corpus cavernosum urethras) and covers by its base the ends of the 
 
 two corpora cavernosa. Its base presents a rounded border, called 
 
 the corona glandis, behind which is a deep sulcus, the cervix (collum 
 
 glandis). 
 Glands of Tyson, small lenticular sebaceous glands opening on the 
 
 corona and cervix of the glans, and secreting an odorous sebaceous 
 
 matter, the smegma. 
 Meatus Urinarius, the external orifice of the urethra, is situated at the 
 
 summit of the glans penis. 
 Prepuce (praeputium), a prolongation of the integument of the penis, 
 
 covering or partly covering the glans penis. 
 Franum Pmputii (fraenulum praeputii), a fold of mucous membrane 
 
 lying along the raphe of the glans penis, and connecting the prepuce 
 
 with the glans. 
 
 Vessels and Nerves. The Arteries are branches of the internal pudic, 
 named as follows: the artery of the bulb, to the bulb of the corpus spongio- 
 sum; the arteries of the corpora cavernosa, to that structure; and the dorsal 
 artery of the penis, to the integument and fibrous sheath of the corpora 
 cavernosa, the glans and prepuce. The 
 
 Helicine Arteries, are vine-like branches, which project into the cavern- 
 ous spaces, and are most abundant in the back part of the corpora 
 
 cavernosa. 
 Veins, empty into the dorsal vein of the penis and the prostatic venous 
 
 plexus. They form intricate and well-developed plexuses in the 
 
 erectile tissue. 
 Lymphatics, the superficial terminate in the inguinal glands; the deep 
 
 join the deep lymphatics of the pelvis. 
 Nerves, are derived from the internal pudic nerve, and the pelvic or 
 
 hypogastric plexus of the sympathetic. 
 
 THE TESTES 
 
 The Testes or Testicles are the glandular organs which secrete the 
 seminal fluid, two oval bodies suspended obliquely in the scrotum by the 
 spermatic cords, each measuring about an inch in diameter, and weighing 
 
THE TESTES 
 
 373 
 
 Their coverings, from without inward, are 6 in number, 
 
 Scrotum (see Fig. 131). 
 
 FIG. 130. 
 
 % oz. to an ounce, 
 as follows: 
 
 Skin (4), of the scrotum. 
 
 Dartos (5), the vascular tunic. 
 
 Inter columnar Fascia, the external spermatic fascia (6, Fig. 131). 
 
 Cremasteric Fascia (7, Fig. 131), muscular fibres, the cremaster muscle, 
 
 derived from the lower border of the internal oblique muscle. 
 Infundibuliform Fascia (9, Fig. 131), internal spermatic fascia, or fascia 
 
 propria; a continuation downward of the transversalis fascia. 
 Tunica Vaginalis, the serous covering, originally a process of the perit- 
 oneum (see below). 
 
 The Scrotum is a cutaneous pouch, consisting of 2 layers the in- 
 tegument and the Dartos; the latter being a contractile vascular tunic, 
 continuous with the superficial fascia of the 
 thighs and perinaeum, and forming a septum in 
 the scrotum between the two cavities for the 
 testes. 
 
 The Epididymis is an appendix to the testicle, 
 lying along its posterior border, and consists of a 
 single 'duct about 20 feet in length when unraveled, 
 but which is wound upon itself so as to occupy a 
 very small space. The 
 
 Head or Globus Major (7), is formed by the 
 coni vasculosi, or efferent ducts (6) of the 
 testis, which therein open into the single duct 
 which forms the epididymis. 
 Body (8), is formed by the convolutions of the 
 tube, held together by fine connective tissue. 
 Tail or Globus Minor (9), the lower expanded 
 portion, similarly formed, and connected to 
 the testis by cellular tissue. 
 Vas or Ductus Aberrans (n), a narrow tube, 
 sometimes found opening into the canal of 
 the epididymis near its lower end, and ending in a blind extremity. 
 Hydatids of Morgagni (appendices testis), small pedunculated bodies, 
 found attached to the epididymis or to the upper end of the testicle. 
 One of them is believed to be the remains of the duct of Muller. 
 
 Tunics of the Testis are 3 in number, the tunica vaginalis, or serous 
 covering, externally; the tunica albuginea, or fibrous covering, in the 
 middle; and the tunica vasculosa, or pia mater testis, internally. The 
 
374 
 
 HUMAN ANATOMY 
 
 FIG. 131. 
 
 Tunica Vaginalis, the serous covering, has a visceral layer (n) (tunica 
 vaginalis propria) and a parietal layer (8) (tunica vaginalis reflexa). 
 Originally a part of the peritoneum, its upper end becomes oblit- 
 erated, and the lower end remains as a closed sac, the space between 
 the layers being the cavity (10) of the tunica vaginalis. It forms a 
 pouch, the digital fossa (13), between the epididymis and the testicle. 
 
 Tunica Albuginea (12), the fibrous covering, consists of white fibrous 
 tissue, and forms ari incomplete vertical septum within the gland, the 
 corpus Highmorianum or medi- 
 astinum testis (2), from which 
 fibrous bands (trabeculae) cross 
 the gland, dividing its interior 
 into spaces for the lobules of 
 the organ. 
 
 Tunica Vasculosa, the vascular 
 covering, lies beneath the 
 preceding, and lines the septa 
 in the interior of the gland. 
 It consists of a plexus of 
 blood-vessels, held together by 
 a delicate areolar tissue. 
 
 Structure of the Testis. The 
 glandular structure consists of 250 
 to 400 olbules, which are each con- 
 tained in one of the spaces formed 
 by the trabeculae, and formed of i 
 to 3 or more minute, convoluted 
 
 tubes, the tubuli seminiferi. The latter consist of a basement mem- 
 brane, lined by several layers of cells, from which the spermatozoa are 
 developed. In the apices of the lobules the tubuli become straight, and 
 join to form 20 or 30 ducts, the 
 
 Vasa Recta (4, Fig. 130), are each about 3^o mcn in diameter; then 
 enter the mediastinum, passing upward and backward, and forming 
 the 
 Rete Testis (5), a network of anastomosing tubes or channels in the 
 
 fibrous stroma of the mediastinum; they end in the 
 Vasa E/erentia (6), 12 to 20 ducts, which perforate the tunica albu- 
 ginea of the testis, and form a number of conical masses, the coni 
 vasculosi which together constitute the globus major (7) of the 
 Epididymis (see Fig. 130). 
 
APPENDAGES OF THE TESTES 375 
 
 Descent of the Testis. In early foetal life the testes are situated in 
 the abdominal cavity, just below the kidneys, and are connected to the 
 dartos of the scrotum and the tissues about the inguinal canal by a cord 
 named the gubtrnaculum testis, which prevents the testicle rising with the 
 growth of the foetus, and the testicle is drawn first into the inguinal canal 
 and eventually into the scrotum, the cord itself becoming shortened as 
 development proceeds. The descent begins about the commencement of 
 the 5th month; during the 7th month the testicle enters the inguinal 
 canal, and ordinarily arrives in the scrotum by the end of the 8th month. 
 A process of peritoneum is carried down in front of the testis; which 
 process, by obliteration of the canal, becomes a separate structure, the 
 tunica vaginalis. The structures of the inguinal canal are also brought 
 down with the testicle, and constitute some of its coverings. 
 
 Vessels and Nerves. The Arteries are the Spermatic, from the aorta 
 to the testicle itself; its coverings are supplied by the superficial and deep 
 External Pudic from the femoral, the superficial Perineal branch of the 
 Internal Pudic from the internal iliac, and the Cremasteric branch of the 
 epigastric from the external iliac. 
 
 Veins. The spermatic veins emerge at the back of the testis, receive 
 branches from the epididymis, and unite into the convoluted pampini- 
 form plexus, which forms the chief mass of the spermatic cord. From 
 this plexus 3 or 4 veins arise, they unite into 2, and these join into 
 a single trunk, which on the right side empties into the inferior vena 
 cava, on the left side into the left renal vein. 
 Lymphatics, of the testis terminate in the lumbar glands; those of its 
 
 coverings in the inguinal glands. 
 
 Nerves, of the testes are derived from the spermatic plexus, joined by 
 filaments from the pelvic plexus; those of their coverings are the ilio- 
 inguinal branch of the lumbar plexus, the superficial perineal branches 
 of the internal pudic, the inferior pudendal branch of the small sciatic, 
 and the genital branch of the genito-crural. 
 
 APPENDAGES OF THE TESTES 
 
 The Vas Deferens (ductus deferens) is the continuation of the 
 epididymis, and the excretory duct of the testicle. Beginning at the 
 globus minor it ascends along the back of the spermatic cord to the in- 
 guinal canal, and enters the abdominal cavity through the internal ab- 
 dominal ring. It curves around the outer side of the epigastric artery, 
 crosses the external iliac vessels, and descends into the pelvis at the side 
 of the bladder, crossing to the inner side of the ureter and the inner 
 border of the vesicula seminalis. At the base of the prostate gland it 
 
376 HUMAN ANATOMY 
 
 joins the duct of the seminal vesicle to form the ejaculatory duct. The 
 vas deferens is about 2 feet long, and has a canal of only half a line in 
 diameter. Its walls are very dense, making it feel like a piece of wire or 
 whip-cord when grasped between the fingers. In structure it consists of 
 three coats, the 
 
 Areolar Coat, externally, beneath which is the 
 
 Muscular Coat, in 2 layers of unstriped fibre, the outer longitudinal, 
 and the inner circular; but a third longitudinal layer is found at the 
 commencement of the vas, internal to the circular layer. 
 
 Mucous Coat, internally, is pale and in longitudinal folds; its epi- 
 thelium is columnar. 
 
 Artery of the Vas or Ductus Deferens, a branch of the superior vesical, 
 
 ramifies on its coats and anastomoses with the spermatic artery. 
 The Spermatic Cord (funiculus spermaticus) extends from the internal 
 abdominal ring to the globus minor of the epididymis, and is about 4 
 inches long. At the external abdominal ring it rests upon the inguinal 
 or Poupart's ligament, having the aponeurosis of the external oblique 
 muscle in front, and the conjoined tendon behind it. It is composed of 
 arteries, veins, lymphatics, nerves, and the vas deferens, bound together 
 by areolar tissue, and invested by the layers brought down by the descent 
 of the testicle. The structures, composing the spermatic cord, are 12 in 
 number, and are named as follows: the 
 
 Vas or Ductus Deferens. Spermatic Plexus of Nerves. 
 
 Spermatic Artery. Branch of the Ileo-inguinal nerve. 
 
 Cremasteric Artery. Branch of the Genito-crural (genito- 
 
 Artery of the Vas Deferens. femoral) Nerve. 
 
 Deferential Veins. Obliterated Processus Vaginalis of the 
 
 Spermatic Veins. peritoneum (ligament of Cloquet). 
 
 Internal Cremaster Muscle. Lymphatics. 
 Coverings of the Cord, from within outward, are the 
 
 Infundibuliform Fascia, from the transversalis fascia. 
 
 Cremasteric Fascia, from the internal oblique muscle. 
 
 Intercolumnar Fascia, the external spermatic fascia. 
 
 Superficial Fascia, and the Skin, of the scrotum. 
 
 The Vesiculae Seminales (d, Fig. 127) are two lobulated membranous 
 pouches, which serve as reservoirs for the semen, and secrete a fluid to 
 be added to the secretion of the testicles. They are about 2^2 inches long, 
 and are situated externally to the lower ends of the vasa or ductus defer- 
 entia, between the base of the bladder and the rectum. They are com- 
 posed of 3 coats, an external areolar, a middle muscular, and an internal 
 
THE VULVA 377 
 
 mucous coat, lined with columnar epithelium. Their anterior extremities 
 converge toward the base of the prostate gland, where a duct from each 
 joins with the corresponding vas or ductus deferens to form 
 
 Ejaculatory Ducts (ductus ejaculatorii), one on each side, are formed 
 by the junction of the vasa or ductus deferentia with the ducts 
 of the vesiculae seminales. They are about % inch in length, and 
 terminate in the prostatic portion of the urethra, by orifices on the 
 sides of the verumontanum (colliculus seminalis). 
 
 Arteries, are derived from the middle and inferior vesical, and the 
 middle haemorrhoidal; they are accompanied by veins and lymphatics. 
 Nerves, are branches from the pelvic or hypogastric plexus. 
 
 THE FEMALE ORGANS OF GENERATION 
 
 (Organa Genital ia Muliebria) 
 
 THE VULVA 
 
 The Vulva, or Pudendum Muliebre, are the external genital organs of the 
 female, viz., the mons Veneris, the labia majora and minora, the clitoris, 
 and the orifice of the vagina. The 
 
 Mons Veneris (commissura labiorum anterior), is the rounded 
 eminence in front of the pubic symphysis, formed of fatty tissue 
 beneath the skin, and covered with hair after puberty. 
 
 The Labia Majora Pudendi (i) are two prominent longitudinal folds 
 extending from the mons Veneris to the perinaeum. They are formed 
 of hairy integument externally and modified skin internally, between 
 which are areolar and dartoid tissues, fat, vessels, nerves, and glands. 
 They meet in front, forming the anterior commissure (10), and nearly meet 
 behind in the posterior commissure at the anterior boundary of the peri- 
 naeum. They correspond to the scrotum of the male. The 
 
 Fourchette (commissura labiorum posterior) (2), is the curved anterior 
 edge of the perinaeum, and between it and the hymen (8) there is a 
 depression, the fossa navicularis. 
 
 Nerves, the superficial perineal from the pudic, and the inferior 
 pudendal from the small sciatic. 
 
 The Labia Minora Pudendi (3), or Nymphce, are two small folds, situated 
 internally to the labia majora, and extending from the prepuce of the 
 clitoris (praeputium clitoridis) (4) obliquely backward for i% inches on 
 each side ot the vaginal orifice, where they are lost on the inner surface 
 of the labia majora. They are composed of modified skin, and have 
 
378 
 
 HUMAN ANATOMY 
 
 FIG. 132. 
 
 sebaceous follicles (glandulaa vestibulares minores) on their internal 
 surface. 
 
 Clitoris, is situated beneath the anterior commissure, its glans (4) 
 
 only appearing externally as a small rounded tubercle between the 
 
 anterior extremities of the labia 
 
 minora. It is a diminutive penis, 
 
 in all but the corpus spongiosum 
 
 and urethra; having two corpora 
 
 cavernosa, two crura, a glans, 
 
 prepuce, suspensory ligament and - 
 
 muscles, the erectores clitoridis 
 
 (ischio-cavernosi) . 
 Vestibule (vestibulum vaginae) (6), 
 
 is a triangular depression in front 
 
 of the vaginal orifice, bounded 
 
 laterally by the labia minora. 
 Meatus Urinarius (orificium urethras 
 
 externum) (5), situated in the 
 
 vestibule, about an inch below the 
 
 clitoris, and close to the vaginal 
 
 orifice. 
 
 Bulbi Vestibuli, are two oblong erec- 
 tile bodies, situated one on either 
 
 side of the vestibule, and consist- a. 
 
 ing of a venous plexus surrounded 
 
 by a fibrous membrane. They are 
 
 the analogues of the bulb of the 
 
 corpus spongiosum in the male. 
 Pars Intermedia, is a small venous plexus situated between the glans 
 
 clitoridis and the bulbi vestibuli. It is the analogue of the corpus 
 
 spongiosum. 
 Orifice of the Vagina (7), is surrounded by the sphincter vaginae 
 
 muscle, and in the virgin is sometimes partly closed by the hymen. 
 ^H^men (8), a fold of mucous membrane situated across the lower part 
 
 of the vaginal orifice, of various shapes, usually a ring, but often 
 
 semilunar, the concavity upward. It is frequently absent in virgins. 
 
 Its cicatrization after rupture gives rise to small eminences along 
 
 the margin of the vaginal orifice, named the caruncula myrtiformes 
 
 (carunculae hymenales). 
 Glands of Bartholin (glandulae vestibulares majores), one on each side 
 
 of the vaginal orifice^ their ducts opening (9) near the inner sides of 
 
THE VAGINA 379 
 
 the labia minora. They are the analogues of Cowper's glands 
 (glandulae bulbo-urethrales) in the male. 
 
 Nerves, to the labia minora as to the labia majora; the bulbi vestibuli 
 and other erectile structures are supplied by filaments from the dorsal 
 nerve of the clitoris, superficial perineal, and hypogastric plexus. 
 
 THE VAGINA 
 
 The Vagina is a curved canal extending from the vulva to the ute ', 
 placed between the bladder in front and the rectum behind. Its len 
 is about 2^ inches along the anterior wall (paries anterior), 3^ inc* 
 along the posterior wall (paries posterior), and its walls are usually in co 
 tact with each other. It is very dilatable, especially near its upper em. 
 which surrounds the vaginal portion of the cervix uteri, its attachment 
 extending higher up on the posterior wall of the uterus than on the anterior 
 wall. Its relations are 
 
 Anteriorly, the urethra and the base of the bladder. 
 Posteriorly, the anterior wall of the rectum, and the recto-vaginal fold 
 of peritoneum which forms Douglas' pouch (excavatio recto-uterina) 
 behind its upper fourth. 
 Laterally, are attached the levatores ani muscles, and the recto-vesical 
 
 portion of the pelvic fascia. 
 
 Structure of the Vagina. The vaginal wall consists of a muscular coat 
 (tunica muscularis) externally, a layer of erectile tissue, and a mucous 
 lining (tunica mucosa) covered with squamous epithelium, and furnished 
 with mucous crypts and follicles, but has no glands. The vagina is par- 
 tially covered laterally by the recto-vesical portion of the pelvic fascia. 
 Columns of the Vagina (columnae rugarum anterior et posterior), 
 are two longitudinal raphes situated along its inner surface, one 
 anteriorly, the other posteriorly, which are connected by numerous 
 transverse ridges or ruga vaginales. 
 Sphincter Vagina Muscle, surrounds the lower end of the vagina; it is 
 
 described on page 99. 
 
 Vessels and Nerves. The Arteries of the vagina are the Vaginal 
 branches of the internal iliac, and branches of the uterine artery, which 
 form in front and behind a longitudinal vessel, the azygos arteries of the 
 vagina. The 
 
 Veins, are disposed similarly to the arteries, form a rich plexus in the 
 muscular and mucous coats, and terminate in the vaginal and uterine 
 trunks. 
 Lymphatics, terminate in the pelvic and inguinal glands. 
 
380 HUMAN ANATOMY 
 
 Nerves, are derived from the hypogastric plexus, the fourth sacral 
 nerve, and the pudic nerve (n. pudendus), forming a vaginal plexus. 
 
 THE UTERUS 
 
 The Uterus is a hollow, pear-shaped, muscular organ, measuring about 
 3 inches long, 2 inches broad, and i inch thick, flattened from before back- 
 ward, placed base upward, forming ah angle with the vagina, which par- 
 tially receives its cervix, and situated in the pelvic cavity, between the 
 bladder in front and the rectum behind. Its 
 
 Fundus uteri (A), is broad, convex, having walls % inch thick, and is 
 
 covered by peritoneum. 
 
 Body (corpus uteri), is about i% inches long, walls % inch thick, flat 
 anteriorly, convex posteriorly, concave laterally, and joined to the 
 bladder by its lower anterior fourth. It is invested by peritoneum 
 posteriorly, and in front for its upper three-fourths. 
 
 FIG. 133. 
 
 Cervix Uteri or Neck, is the lower constricted portion, about i % inches 
 long, walls Y inch in thickness, and is embraced for % to % inch 
 by the upper extremity of the vagina. 
 
 Cavity of the Body (cavum uteri) (B), is small and triangular, flattened 
 from before backward, about i% inches in length, and has two lateral 
 cornua above, and a constricted orifice, the os internum (orificium in- 
 ternum uteri), at its lower angle, opening into the cavity of the 
 cervix. 
 
 Cavity of the Cervix (canalis cervicis uteri), is spindle-shaped, about 
 i% inches long, and presents on its inner surf ace transverse folds of 
 mucous membrane proceeding from a longitudinal fold, giving an 
 appearance named the arbor vitce (plicae palmatae) (o). 
 
 Os Uteri (orificium externum uteri), is a transverse orifice at the lower 
 
THE UTERUS 381 
 
 end of the cervical cavity, opening into the vagina, and having an 
 anterior (labium anterius) and a posterior lip (labium posterius). 
 
 Ligaments of the Uterus are 8 in number, i anterior, i posterior, 2 
 lateral or broad ligaments, 2 sacro-uterine, and 2 round ligaments, all 
 except the last-named being formed of peritoneum. The 
 
 Anterior Ligament, utero-vesical, is reflected from the front of the 
 uterus on to the bladder. It forms the floor of the utero-vesical pouch 
 (excavatio vesico-uterina). 
 
 Posterior Ligament, recto-vaginal, passes from the posterior wall of the 
 uterus over the upper fourth of the vagina, and thence on to the 
 rectum and sacrum, forming Douglas' pouch (excavatio recto-uterina) 
 behind the upper portion of the vagina. 
 
 Lateral or Broad Ligaments (ligamenta lata uteri) 2, pass from the 
 sides of the uterus to the lateral walls of the pelvis, and form a septum 
 across the pelvic cavity. They contain, between the two folds of 
 peritoneum of which they are composed, the Fallopian tubes (tubae 
 uterinas) the round ligaments, the ovaries, the parovaria or organs of 
 Rosenmiiller, connective tissue, unstriped muscular fibre, blood- 
 vessels, and nerves. 
 
 Sacro-uterine Ligaments (plicae recto-uterinae) 2, pass from the sides 
 of the uterus to the sides of the rectum, and thence to the sacrum. 
 
 Round Ligaments (ligamenta teres uteri) 2 (G), are two cords, about 4 
 or 5 inches long, composed of muscular tissue prolonged from the 
 uterus, also areolar and fibrous tissue, vessels and nerves, extending 
 one on each side, from the lateral aspects of the fundus uteri, through 
 the inguinal canals, to the labia majora, where they are lost. Each 
 ligament lies, for a part of its course, between the two layers of the 
 broad ligament, and is covered by a process of peritoneum. The 
 
 Canal of Nuck, is the extension of the above-mentioned process of 
 peritoneum into the inguinal canal. It exists in the foetus, but is 
 usually obliterated in the adult. 
 
 Structure of the Uterus. The wall of the uterus is composed of 3 
 coats, an External serous, a middle muscular, and an internal mucous coat. 
 The muscular coat (tunica muscularis) forms the chief bulk of the organ, 
 and consists of bundles of unstriped muscular fibres, disposed in 3 layers 
 interlaced together; circular fibres predominating in the cervix, longi- 
 tudinal fibres in the body of the uterus. The 
 
 Peritoneal or Serous Coat (tunica serosa), invests the body of the 
 organ, except its lower anterior fourth. 
 
 Mucous Coat (tunica mucosa), is very thick, ^(2 to 3^ inch, and closely 
 
382 HUMAN ANATOMY 
 
 adherent to the muscular tissue, having no basement layer of con- 
 nective tissue. It is covered with ciliated columnar epithelium, and 
 studded with mucous follicles and tubular glands (glandulse uterinae), 
 which are most numerous in the cervix. 
 
 Vessels and Nerves. The Arteries of the uterus are the Uterine from 
 the internal iliac, and the Ovarian from the aorta; the two meeting on the 
 side of the body and forming an anastomotic trunk, from which lateral 
 branches are given off to the uterus. They are remarkably tortuous and 
 anastomose freely. The 
 
 Veins, accompany the arteries, and in the impregnated state become 
 
 sinuses. They end in the uterine plexuses. 
 Lymphatics, those of the cervix end in the pelvic glands, those of the 
 
 body in the lumbar glands. 
 
 Nerves, are derived from the inferior hypogastric and ovarian plexuses, 
 and from the 3d and 4th sacral nerves. 
 
 APPENDAGES OF THE UTERUS 
 
 The Fallopian Tubes, or Oviducts (tubas uterinae) (D), are two tubes, 
 
 each about 4 inches in length, and i H 6 inch in calibre, situated in the free 
 
 margin of the broad ligament, and extending from the superior angles of 
 
 the uterus (&) outward, to terminate in free, trumpet-shaped ends. They 
 
 open by one end into the uterus at its cornua, by the other end into the 
 
 peritoneal cavity. Their structure is similar to that of the uterus, the 
 
 mucous lining being continuous with the uterine mucous membrane and 
 
 with the peritoneum, and lined with ciliated columnar epithelium. Their 
 
 Isthmus Tubes Uterines, is the inner constricted third of the tube. 
 
 Ampulla Tubes Uterines, is the outer dilated portion, curving over the 
 
 ovary. 
 Infundibulum Tubes Uterince, the trumpet-shaped outer end, with its 
 
 open mouth, the ostium abdominale tubce uterince, surrounded by 
 Fimbrice Tubes Uterines (E), fringe-like processes, one of which, the 
 
 fimbria ovarica, is attached to the ovary. 
 
 Hydatids of Morgagni (appendices vesiculosi) (see page 372), one or 
 more small vesicles floating on a long stalk of peritoneum, are fre- 
 quently found in connection with or near the fimbriae. 
 Vessels and Nerves, The vessels are those of the ovaries; the nerves are 
 
 branches from one of the uterine nerves. 
 
 The Ovaries (ovaria) (F) are two oval bodies, of grayish-pink color, 
 situated in the broad ligament, behind and below the Fallopian tubes, 
 ( tubae uterinae,) one on each side of the uterus, to which they are attached 
 
 
THE MAMMAE 383 
 
 by the ligament of the ovary. They each measure about i % inches by % 
 by H, and are invested by peritoneum, except posteriorly. They are 
 composed of a vascular stroma containing the Graafian vesicles (folliculi 
 oophori vesiculosi) in various stages of development, and are surrounded 
 by the tunica albuginea, a condensed layer of the stroma. 
 
 The Graafian Vesicles (folliculi oophori vesiculosi) are the ovisacs 
 containing the ova, are very numerous (about 70,000 in each 
 ovary), vary in diameter from Hoo to %o inch, but after puberty a few 
 are found of from Ho to ^ inch or more. Each vesicle has an external 
 fibro-vascular coat, and an internal coat (tunica externa) or ovicapsule, 
 (theca folliculi) which is lined by the membrana granulosa (stratum 
 granulosum) and contains a transparent fluid of albuminous character, 
 containing the immature ovum. The 
 
 Membrana Granulosa (stratum granulosum), is a layer of nucleated 
 cells, lining the ovicapsule; at one point the cells are heaped up in a 
 mass, the discus proligerus (cumulus oophorus), in which the ovum 
 is embedded. 
 
 Corpus Luteum, is a puckered yellow spot in the substance of the 
 ovary, produced as a result of the rupture of a Graafian vesicle and the 
 discharge of an ovum, probably by the organization of the extrava- 
 sated blood, forming lutein cells. In old age the corpus luteum 
 undergoes involution, loses its yellow color, and is then called the 
 corpus albicans. 
 
 Vessels and Nerves. The Arteries are the Ovarian, from the aorta, 
 which also supply the Fallopian tubes, and anastomose with the uterine 
 arteries. The 
 
 Veins, accompany the arteries, and form a plexus, the pampiniform 
 
 plexus, near the ovary. 
 Nerves, are derived from the inferior hypogastric or pelvic plexus, and 
 
 from the ovarian plexus. 
 
 The Parovarium, or Organ of Rosenmuller, is a group of tubules, situated 
 in the broad ligament, between the ovary arid the Fallopian tube, and con- 
 verging to a large duct, the duct of Gartner, which ramifies in the broad 
 ligament, descends along the side of the uterus, and terminates in a bulb- 
 ous enlargement. It is the atrophied remains of the Wolffian Body of 
 fcetal life. 
 
 THE MAMMAE 
 
 The Mammae, or Breasts, are two hemispherical eminences, situated one 
 on each antero-lateral aspect of the chest, extending from the sternum 
 to the axilla, and from the 3d rib to the 7th. Each breast contains the 
 
384 
 
 HUMAN ANATOMY 
 
 Mammary Gland (corpus mammae) and is surmounted by the nipple 
 (papilla mammae), around the base of which is a zone of colored cutaneous 
 tissue, the areola mamma, pink in virgins, darker in women who have 
 borne children. In the male the mammae 
 
 .r IG 134" 
 
 are rudimentary organs, but capable of 
 development under special circumstances. 
 Structure of the Mammary Gland. Is 
 composed of 15 or 20 lobes (lobi mammae) 
 and their ducts (i), with a packing of 
 areolar and adipose tissue (subcutaneous 
 tela), enveloped by a thin fibrous capsule 
 or stroma which forms septa between the 
 lobes. Each lobe is made up of lobules 
 (2), and these again are formed by the 
 aggregation of alveoli, terminal vesicles 
 by which the milk is secreted. The 
 Tubuli Lactiferi (ductus lactiferi) (i), 
 
 are the excretory ducts of the 
 
 lobes, one for each. They are formed 
 
 by the junction of the ducts from 
 
 each lobule, and converge towards 
 
 the areola, beneath which they form 
 
 ampulla or dilatations, and thence, 
 
 piercing the nipple, open on its summit by separate orifices. 
 Vessels and Nerves. The Arteries are derived from the thoracic 
 branches of the axillary, the intercostals, and the internal mammary 
 arteries. 
 
 Veins, form the circulus venosus, an anastomotic venous circle around 
 
 the base of the nipple, from which larger veins run outward, and ter- 
 minate in the axillary and internal mammary veins. 
 Lymphatics, terminate in the axillary glands; a few going to the 
 
 anterior mediastinal glands. 
 Nerves, are derived from the lateral cutaneous branches of the 4th, 
 
 5th, and 6th intercostal nerves and from the thoracic portion of the 
 
 sympathetic cord. 
 
 HERNIA 
 
 A Hernia is a protrusion of any viscus from its natural cavity. The 
 term, when unqualified as to the viscus, is understood to mean a protrusion 
 of the intestines or mesentery, or both, from the abdominal cavity. Ana- 
 tomically the most important hernias are 
 
INGUINAL HERNIA 385 
 
 Oblique Inguinal Hernia, in which the protrusion follows the spermatic 
 cord through the inguinal canal; passing to the outer side of the epi- 
 gastric artery, and through both the internal and external abdominal 
 rings. 
 
 Direct Inguinal Hernia, occurs at Hesselbach's triangle, escaping to 
 the inner side of the epigastric artery, and through the subcutaneous 
 inguinal or external abdominal ring only. 
 
 Femoral Hernia, in which the protrusion descends through the femoral 
 or crural canal. 
 
 H INGUINAL HERNIA 
 
 The Inguinal Canal is a passage in the abdominal wall, parallel to the 
 inguinal or Poupart's ligament, and just above it. It commences at the 
 abdominal inguinal or internal abdominal ring and ends at the subcu- 
 taneous inguinal or external abdominal ring (i), being about i^ inches in 
 length. It serves for the passage of the spermatic cord in the male, and 
 the round ligament of the uterus in the female; is directed downward and 
 inward, and is bounded as follows: 
 
 Anteriorly, the skin, superficial fascia, (camper's) external oblique 
 muscle for its entire length, and the internal oblique (the part 
 attached to the inguinal ligament) for the outer third of the canal. 
 Posteriorly, the conjoined tendon of the internal oblique and trans- 
 versalis, transversalis fascia, triangular fascia (5) for the medial 
 two-thirds, sub-peritoneal tissue, transversalis fascia, and peritoneum 
 for its entire length. 
 Above, the arched fibres of the internal oblique and transversalis 
 
 muscles. 
 
 Below, the union of the transversalis fascia (5) with Poupart's (in- 
 guinal) ligament (10). 
 
 The Internal or Deep Abdominal Ring (annulus inguinalis abdo minis), 
 is an oval opening in the transversalis fascia, formed by the prolongation 
 of this fascia around the cord, as the infundibuliform fascia. It lies Y 2 
 inch above Poupart's (inguinal) ligament (10) and midway between the 
 anterior superior spine of the ilium and the spine of the pubes (8). It is 
 bounded above and externally by the arched fibres of the transversalis 
 muscle; below and internally by the epigastric vessels. The 
 
 Deep Epigastric Artery, lies between the transversalis fascia and the 
 peritoneum, passing obliquely upward and inward along the lower and 
 inner margins of the internal ring. 
 
 Infundibuliform Fascia, or infundibuliform process of the transversalis 
 fascia, is a thin, funnel-shaped membrane, arises from the circum- 
 25 
 
386 
 
 HUMAN ANATOMY 
 
 ference of the internal ring, and is continued (internal spermatic 
 fascia) around the cord and testis, enclosing them in a distinct 
 pouch. 
 
 The External or Superficial Abdominal Ring (annulus inguinalis sub- 
 cutaneous) (i), is a somewhat triangular opening in the aponeurosis of 
 the external oblique muscle, situated just above and external to the crest 
 of the pubes. It is about i inch long, and ^ inch wide, and is bounded 
 laterally by its own margins, called the external (crus inferius) (2) and 
 internal (crus superius) (3) pillars of the ring. It may be easily felt in 
 
 10 
 
 the living male, by invaginating the skin of the scrotum with the finger, 
 and feeling up along the spermatic cord (9). It is much larger in men 
 than in women. The 
 
 Inter columnar or External Spermatic Fascia (fibrae intercrurales) (6), 
 is formed by tendinous fibres which arch across the lower part of the 
 aponeurosis of the external oblique, between the pillars of the ex- 
 ternal ring, and are connected together by delicate fibrous tissue. 
 It is continued downward as a tubular prolongation around the cord 
 and testis, enclosing them in a distinct sheath. 
 
 Cremasteric Fascia (fascia cremasterica), passes through the external 
 ring, and consists of a series of muscular loops, united by areolar 
 tissue, forming a thin covering over the spermatic cord and testis. 
 
INGUINAL HERNIA 
 
 38? 
 
 The muscular fibres (Cremaster muscle) are supposed to have been 
 originally part of the internal oblique muscle, carried down by the 
 testicle in its descent to the scrotum. It does not exist in the 
 female. 
 
 FIG. 136. 
 
 Poupart's Ligament (ligamentum inguinale), or the Crural Arch, is 
 that portion of the aponeurosis of the external oblique muscle which 
 
 extends from the anterior supe- 
 rior spine of the ilium to the 
 spine of the pubes. Its lower 
 portion (3) forms the external 
 pillar of the external abdominal 
 ring, and its reflection along the 
 pectineal line is called Gimbernafs 
 ligament (ligamentum lacunare) 
 (2). Other fibres, reflected be- 
 hind the internal pillar of the 
 ring (4), upward to the linea 
 alba, are termed the triangular 
 fascia (ligamentum inguinale re- 
 flexum) (i). 
 
 Gimbernat's Ligament (liga- 
 mentum lacunare) (2), is 
 that portion of the aponeu- 
 rosis of the external oblique 
 which is reflected upward 
 and outward from the spine 
 of the os pubis to be inserted 
 into the pectineal line. Its> 
 anterior margin is continuous with Poupart's (inguinal) ligament. 
 Triangular Fascia (ligamentum inguinale reflexum) (i), is a tri- 
 angular band, attached by its apex to the pectineal line, where it ia 
 continuous with Gimbernat's (lacunar) ligament; passes inward 
 beneath the spermatic cord, behind the internal pillar (crus superius) 
 of the external or subcutaneous inguinal ring, and in front of the 
 conjoined tendon, to interlace with its fellow of the opposite side at 
 the linea alba (see 5, Fig. 134). It is often undeveloped or wanting. 
 
 Hesselbach's Triangle is a small triangular space on the lower ab- 
 dominal wall, bounded externally by the deep epigastric artery, internally 
 by the margin of the rectus muscle, below by Poupart's (inguinal) liga- 
 
388 HUMAN ANATOMY 
 
 ment. Its inner ^ is crossed by the conjoined tendon. Through this 
 space a direct inguinal hernia forces its way. The 
 
 Inguinal Peritoneal Fossce, are 3 depressions of peritoneum in the in- 
 guinal region above Poupart's (inguinal) ligament. The internal 
 (fovea supravesicalis) and middle (fovea inguinalis medialis) ones lie 
 in Hesselbach's triangle, the external fossa (fovea inguinalis lateralis) 
 usually corresponds to the internal abdominal or abdominal inguinal 
 ring. 
 
 Coverings of Inguinal Hernia depend, in the oblique form, upon the 
 extent to which the hernia descends in or through the inguinal canal. 
 When it has escaped from the external abdominal or subcutaneous in- 
 guinal ring, and is therefore complete, its coverings, from without inward, 
 are 7 in number, as follows: 
 
 1. Skin. 
 
 2. Superficial Fascia, 2 layers. 
 
 3. Inter columnar Fascia, from the external abdominal ring. 
 
 4. Cremasteric Fascia, from the inguinal canal. 
 
 5. Infundibuliform Fascia, from the internal abdominal ring. 
 
 6. Subserous Areolar Tissue, almost inappreciable. 
 
 7. Peritoneum, the hernial sac proper. 
 
 Direct Inguinal Hernia has the same coverings, except that the Conjoined 
 Tendon is substituted for the cremasteric fascia, and the Transversalis 
 Fascia for the infundibuliform. 
 
 FEMORAL HERNIA 
 
 The Femoral or Crural Canal is a narrow interval, % to % inch long, 
 
 between the femoral vein (4) and the inner wall of the femoral sheath 
 
 (fascia cruris), extending from Gimbernat's (lacunar) ligament to the 
 
 saphenous opening (fossa ovalis). It exists as a distinct canal only when 
 
 the sheath has been separated from the vein by the pressure of a hernia 
 
 or tumor, or by dissection. It lies beneath Poupart's (inguinal) ligament 
 
 (i), is closed above by the septum crurale of Cloquet (septum femorale), 
 
 below by the cribriform fascia (fascia cribrosa), and is bounded as follows: 
 
 Anteriorly, by a continuation downward, under Poupart's (inguinal) 
 
 ligament, of the transversalis fascia, covered by the falciform process 
 
 (margo falciformis) of the fascia lata. 
 
 Posteriorly, by a downward continuation of the iliac fascia, covering 
 
 the pubic portion of the fascia lata. 
 
 Externally, by the fibrous septum separating it from the inner side of 
 the femoral vein. 
 
FEMORAL HERNIA 
 
 389 
 
 FIG. 137. 
 
 Internally, by the outer edge of Gimbernat's (lacunar) ligament, and 
 the junction of the processes of the transversalis fascia and the iliac 
 fascia, which form the inner side of the femoral sheath. 
 
 The Femoral or Crural Ring (annul us femoralis), the upper opening of 
 the femoral canal, is an oval-shaped opening, about ^ inch in diameter 
 
 (larger in the female), situated 
 below the internal abdominal or 
 subcutaneous inguinal ring (7) and 
 Poupart's (inguinal) ligament (i), 
 and between the inner side of the 
 femoral vein and the margin of 
 Gimbernat's (lacunar) ligament 
 (5). It is closed by the septum 
 crurale (septum femorale) and a 
 small lymphatic gland. The arrow 
 in the figure points into the fem- 
 oral ring. The 
 Femoral Vein (4), lies next on 
 
 its outer side. 
 
 Deep Epigastric Artery (a. epi- 
 gastrica inferior), crosses its 
 upper and outer angle. 
 
 Obturator Artery, when arising from a common trunk with the epi- 
 gastric, as it does once in 3^ subjects, may lie close along its internal 
 and superior margins. 
 Communicating Branch, between the deep epigastric and obturator 
 
 arteries, lies in front of the ring. 
 Spermatic Cord (funiculus spermaticus), in the male, lies directly above 
 
 its anterior margin, replaced by the round ligament in the female. 
 Septum Crurale, or Fascia of Cloquet (septum femorale), is a layer of 
 condensed areolar tissue, supporting a lymphatic gland, and per- 
 forated for the passage of lymphatic vessels. It lies across the femoral 
 ring, and forms one of the coverings to any hernia escaping thereby. 
 
 The Saphenous Opening (fossa ovalis), the lower orifice of the femoral 
 canal, is an oval-shaped aperture, i^ by ^ inch in diameter, formed by a 
 reflection of the fascia lata inward, around and under the end of the in- 
 ternal saphenous vein (3). It is situated below the inner third of Pou- 
 part's (inguinal) ligament, and is covered by the cribriform fascia (fascia 
 cribrosa). Its inner margin curves upward behind the saphenous vein 
 and under the outer margin, and is blended with the pubic portion of the 
 
HUMAN ANATOMY 
 
 fascia lata over the pectineus muscle. Its outer margin curves over the 
 
 inner to the spine of the pubes, as a 
 
 Falciform Process, or Superior Cornu (margo falciformis), is thin but 
 strong, sharply defined, and lies on a plane anterior to the inner 
 margin. It ascends in front of the femoral vessels, and curving 
 inward is attached toPoupart's (inguinal) ligament, the spine of theos 
 pubis, and the pectineal line, where it is continuous with the pubic 
 portion. It is sometimes named the ligament of Burns, its pubic end 
 is called the ligament of Hey. 
 
 Cribriform Fascia (fascia cribrosa) (n, Fig. 134), is the portion of the 
 deep layer (Scarpa's) of the superficial fascia which covers the 
 saphenous opening (fossa ovalis). It is perforated by the internal 
 saphenous vein and by numerous blood-vessels and lymphatics. 
 
 The Femoral or Crural Sheath, the investing sheath of the femoral ves- 
 sels, is a funnel-shaped prolongation of the lining fasciae of the abdomen, 
 the transversalis fascia in front, and the iliac fascia behind. The sheath 
 is divided by two septa into 3 compartments, the external of which 
 contains the femoral artery, the middle one the femoral vein, the internal 
 one being the femoral canal. The sheath is perforated anteriorly by the 
 genito-crural nerve, internally by the internal saphenous vein, and forms 
 one of the coverings of a femoral hernia. The 
 
 Deep Crural Arch, is the thickened border of the transversalis fascia, 
 
 which arches across the front of the crural sheath, and is intimately 
 
 connected to it. Externally it is attached to the centre of Poupart's 
 
 (inguinal) ligament, internally it is inserted into the pectineal line 
 
 /behind the conjoined tendon. 
 
 Coverings of Femoral Hernia depend upon whether the hernia has or 
 has not escaped from the saphenous opening (fossa ovalis) , and is therefore 
 complete or incomplete. In the latter case, the covering, from without 
 inward would be skin, superficial fascia, cribriform fascia, femoral 
 sheath, septum crurale, subserous areolar tissue (fascia propria of Sir 
 Astley Cooper), and peritoneum. The coverings of a complete femoral 
 . Jifitnia. axe. as follows: 
 
 i. Skin. 
 I 2. Superficial Fascia, its superficial layer (subcutaneous tela). 
 
 3. Cribriform Fascia, from the saphenous opening. 
 
 4. Femoral Sheath, from the transversalis fascia. 
 
 5. Septum Crurale, from the femoral ring. 
 
 6. Subserous Areolar Tissue, the fascia propria of Cooper. 
 
 7. Peritoneum, the proper hernial sac. 
 
THE PELVIC CAVITY 39 1 
 
 THE PERINEUM, PROPER 
 
 The Perinaeum is a triangular space containing the structures which 
 close the inferior outlet of the pelvic cavity anterior to a line drawn be- 
 tween the tuberosities of the ischia. Posteriorly to thisline the correspond- 
 ing space is named the I schio-rectal Region. The Perinaeum is bounded 
 laterally by the rami of the pubes and ischia, anteriorly by the symphysis 
 pubis, and posteriorly by the line above mentioned, which averages about 
 2% inches in length. 
 
 For the Muscles of the Perinaeum, see page 98. 
 
 THE PELVIC CAVITY 
 
 The Pelvic Cavity is that portion of the abdominal cavity which lies 
 below the level of the ilio-pectineal line and the promontory of the sacrum. 
 The osseous pelvis is described on page 9. The boundaries of the pelvic 
 cavity are as follows: 
 
 Anteriorly and Laterally, the pubes and ischia, covered by the obturator 
 
 muscles. 
 Posteriorly, the sacrum and coccyx, the pyriformis muscles, and the 
 
 great sacro-sciatic ligaments (lig. sacro-tuberosa). 
 Floor, is formed by the recto-vesical fascia, covering the levator ani 
 and coccygeus muscles of each side, and the triangular ligament 
 (diaphragma-urogenitale) of the urethra. 
 
 Contents of the Pelvic Cavity are the bladder, rectum, some convolu- 
 tions of the small intestine, and some of the organs of generation. They 
 are partially covered by peritoneum, and supplied with vessels and nerves. 
 
 THE PELVIC FASCIA 
 
 The Pelvic Fascia lines the pelvic cavity and is continuous with the 
 
 iliac and transversalis fascia above. At the level of a line drawn from the 
 
 back of the symphysis pubis to the spine of the ischium, it is thickened into 
 
 a white line or band (arcus tendineus), where it gives origin to the levator 
 
 ani muscle, and divides into 2 layers, the recto-vesical fascia or visceral 
 
 layer, and the obturator fascia or parietal layer. The 
 
 Recto-vesical Fascia, visceral layer of the pelvic fascia, descends from 
 
 the white line (arcus tendineus) over the upper or pelvic surface of 
 
 the levator ani muscle, and is prolonged over the prostate gland, 
 
 rectum, vesiculae seminales, and the bladder, forming the lateral true 
 
 ligaments of the latter organ. 
 
 Obturator Fascia, the parietal layer of the pelvic fascia, descends from 
 the white line along the wall of the pelvis, and covers the obturator 
 
392 
 
 HUMAN ANATOMY 
 
 interims muscle, near the lower border of which it forms a canal be- 
 tween its layers, Alcock's canal) for the pudic vessels and nerve. 
 Above this canal it gives off a thin membrane, the ischio-rectal or anal 
 fascia over the lower or perineal surface of the levator ani muscle; also 
 a process, which with its fellow of the opposite side forms the deep 
 (superior) layer of the triangular ligament (diaphragma urogenitale). 
 Illustration of the Pelvic Fascia. The capital letter K, having a hori- 
 zontal arm added to it, thus K, will illustrate the pelvic fascia of the right 
 side, seen from the front in vertical section. The vertical line of the K 
 represents the pelvic fascia above, the obturator fascia below. The upper 
 arm represents the lateral ligament of the bladder, the horizontal arm the 
 recto-vesical fascia, and the lower arm the ischio-rectal fascia. The space 
 between the lower arm and the vertical line represents the ischio-rectal 
 fossa. 
 
 THE MALE PERINEUM 
 
 The Male Perinaeum, in the adult, varies in breadth on the base line, 
 from 2 to 3^ inches, the average FIG. 138. 
 
 being 2% inches. Its middle line 
 is convex, corresponds to the bulb 
 of the urethra, and presents a 
 prominent raphe, which is con- 
 tinuous in front with the raphe 
 of the scrotum. Its muscles are 
 described on page 98. 
 
 Fasciae of the Perinaeum are 
 superficial and deep, each con- 
 sisting of two layers; the deep 
 fascia being usually called the 
 triangular ligament of the urethra. 
 The 
 
 Superficial Layer of the Super- 
 ficial Fascia (subcutaneous 
 tela), is thick, loaded with 
 fat, and continuous with the 
 subcutaneous fascia of the 
 thighs. 
 
 Deep Layer of the Superficial Fascia, Colics' Fascia, is thin but strong, 
 continuous in front with the dartos of the scrotum, and attached on 
 each side to the rami of the pubes and ischium; posteriorly it joins the 
 deep perimeal fascia under the superficial transversus perinaei muscle. 
 
THE MALE PERINEUM 393 
 
 Superficial Layer of the Deep Perinaal Fascia (fascia diaphragmatis 
 urogenitalis inferior), is triangular in shape, and extends from the 
 sides of the pubic arch and the sub-pubic ligament, laterally to the 
 rami of the pubes and ischia, and posteriorly to the central tend- 
 inous portion of the perinaeum, where it becomes blended with 
 Colic's fascia and the deep layer of the deep fascia. It embraces 
 the anterior part of the membranous portion of the urethra. 
 Deep Layer of the Deep Perinceal Fascia (fascia diaphragmatis urogenitalis 
 superior), has the same attachments as the superficial layer above 
 described, in its course it embraces the posterior part of the mem- 
 branous portion of the urethra, and is in connection with the apex 
 of the prostate gland. 
 
 Buck's Fascia is a continuation of the deep layer of the superficial fascia 
 of the perinaeum, extending forward upon the penis, which itinvests com- 
 pletely as far as the glans. It is continuous above with the suspensory 
 ligament of the penis, and is held by some anatomists to prove that the 
 deep layer aforesaid is not continuous in front with the dartos of the 
 scrotum. This fascia was named from Dr. Buck, an American surgeon, 
 who, in 1846, first insisted on the importance of this structure. It modifies 
 the direction of urinary infiltration of the perinaeum, until perforated. 
 The Superficial Perin&al Interspace or Fossa is the interval between the 
 deep layer of the superficial fascia (Colles' fascia) and the triangular 
 ligament or urogenital diaphragm. It contains the following 
 structures: 
 
 Crura of the Penis (4). 1 ' schio-cavernosus or Erector Penis 
 
 Corpus Spongiosum (corpus Muscle (10). 
 
 cavernosum urethrae). Superficial Transversus Pcrincei 
 
 Bulb of the Urethra. Muscle (14). 
 
 Bulbo-cavernosus or Accelerator Superficial Transversus Perinai 
 Urines Muscle (8). Artery. 
 
 Superficial Perinaal Vessels and 
 
 Nerves (5). 
 
 The Deep Perinceal Interspace or Fossa is the interval between the two 
 layers of the triangular ligament or urogenital diaphragm. It 
 contains the following structures: 
 
 Membranous Urethra. Dorsal Vein of the Penis. 
 
 Deep Transversus Perinai or Com- Artery of the Bulb, 
 pressor Urethrce Muscle. Nerve of the Bulb. 
 
 Pudic Vessels and Nerve (n). Plexus of Veins. 
 
 Cowper's Glands (glandula bulbo- 
 yrethrales) and Ducts. 
 
394 
 
 HUMAN ANATOMY 
 
 Central Tendinous Point is a fibrous point in the middle line of the 
 perinaeum, internal to the deep layer of the superficial fascia and about % 
 inch in front of the anus. It corresponds to the centre of the posterior 
 margin or base of the triangular ligament or urogenital diaphragm (12), 
 and is the point of attachment for 4 converging muscles, the external 
 sphincter (16), bulbo-cavernosus or accelerator urinae (8), and two super- 
 ficial transverse perinaeal (14). 
 
 ISCHIO-RECTAL REGION 
 
 The Ischio-rectal Space is the horse-shoe-shaped space behind and above 
 the perinaeum. It is somewhat triangular in cross-section. It extends 
 posteriorly to the tip of the coccyx, laterally to the tuberosities and rami 
 of the ischia and anteriorly, on each side, it presents an Anterior Exten- 
 sion which extends forwards as far as the body of the pubis. In fat sub- 
 jects this extension is distended with fat, in which case it is triangular 
 
 FIG. 139. 
 
 in cross -section, the floor being formed by the deep layer of the trian- 
 gular ligament (uro-genital diaphragm), outer wall by obturator fascia 
 and muscle, and the inner wall by the leva tor an i muscle and its fascia. 
 In the middle line it presents the anal orifice, and deeply on each side, 
 the Ischio-rectal Fossa, which contains the lower part of the rectum, areolar 
 tissue and fat. The fossa is about i inch broad at its base and about 2 
 
THE FEMALE PERINEUM 395 
 
 inches deep; its apex, directed upward, corresponds to the junction of the 
 obturator fascia and the ischio-rectal fascia. It contains the 
 
 Superficial Fascia (subcutaneous tela), is thick, areolar in texture, 
 with much fat in its meshes, also branches of the perforating cu- 
 taneous nerve. It is a single layer. 
 
 Muscles, the corrugator cutis ani, external and internal sphincters (16), 
 and the levator ani (18). 
 
 Rectum, surrounded by areolar tissue and fat. 
 
 Internal Pudic (pudenda!) Artery (n), with its veins and the two 
 divisions of the nerve, about ^ inch above the margin of the tuber- 
 osity of the ischium. 
 
 Inferior Hemorrhoidal Vessels and Nerves (13), cross the space trans- 
 versely. 
 
 Superficial Perinceal Vessels (5) and Nerves (3), in the front part of the 
 space for a short distance. 
 
 Branch of the ^th Sacral Nerve, at the back of the space, near the coccyx. 
 
 Ischio-rectal or Anal Fascia, a thin membrane given off from the obtu- 
 rator fascia over the levator ani muscle, at the apex of the fossa (see 
 pages 390-391). 
 
 Obturator Fascia, covering the obturator internus muscle, at the outer 
 side of the fossa (see page 390). 
 
 Recto-vesical Fascia, invests the internal surface of the levator ani 
 muscle, near the base of the fossa; also the rectum at the inner side 
 of the fossa (see page 390). 
 
 THE FEMALE PERINEUM 
 
 The Female Perinaeum performs the special function of supporting the 
 posterior wall of the vagina, and thereby aiding materially in the support 
 of the whole vagina, the uterus and the bladder. The 
 
 PerincBal Body, is the pyramidal-shaped prolongation of the female 
 perinaeum upward between the vagina and the rectum. It measures 
 about \Y inches antero-posteriorly, and extends laterally from one 
 ischial tuberosity to the other. In it are situated the muscles of the 
 external organs of generation. 
 
 Differences between the Female and Male Perinsea are chiefly due 
 to the perforation of the structures in the median line of the female 
 perinaeum by the vulvo-vaginal passage. The 
 
 Superficial Fascia, is incomplete, by reason of its perforation by the 
 orifice of the vulva, but consists of two layers, subcutaneous tela and 
 Colics' fascia, as in the male. 
 
396 HUMAN ANATOMY 
 
 Deep Perinaal Fascia (urogenital diaphragm), being also perforated 
 by the vagina is less apparent than in the male, though presenting 
 two layers, with the urethra perforating them, as in the other sex. 
 
 Bulbi Vestibuli and Paries Intermediates, represent the corpus spongio- 
 sum of the male, divided into two lateral segments. 
 
 Prostate Gland, is absent in the female, but its place is occupied by a 
 number of minute glands disposed around the neck of the bladder. 
 
 Muscles, The Sphincter Vaginae in the female, takes the place of the 
 bulbo-cavernosus or accelerator urinse in the male; the Superficial 
 Transversus Perinaei is similar in both sexes; the Erector Clitoridis 
 is smaller than the erector penis, but differs in no other respect; 
 both are called ischio-cavernosus; the Deep Transversi Perinaei 
 or Compressores Urethras are separate and attenuated in the 
 female, their anterior fibres passing in front of the urethra, the 
 middle fibres to the sides of the vagina, the posterior fibres to 
 the central tendinous point of the perinaeum. 
 
 Structures Divided in Lithotomy. In the Lateral Operation the 
 knife is inserted deeply i^ inches in front of the anus, a little to the left 
 of the median line, and the incision is carried obliquely backward and 
 outward, becoming more superficial as it is extended, to a point midway 
 between the anus and the tuberosity of the left ischium, dividing the 
 
 Skin and Superficial Fascia (first layer of the latter). 
 
 Inferior Hemorrhoidal Vessels and Nerves (13). 
 
 Deep Layer of the Superficial Fascia (6). 
 
 Superficial Perinaal Vessels (5) and Nerves (3). 
 
 Bulbo-cavernosus (Accelerator Urinae) Muscle (8) (posterior fibres). 
 
 Superficial Transversus Ferincei Muscle (14) and Artery. 
 
 Inferior Layer of the Triangular Ligament (12). 
 
 Deep Transversus Perin&al (Compressor Urelhrce) Muscle (a few fibres). 
 
 Levator Ani Muscle (18) (anterior fibres). 
 
 Membranous and Prostatic Portions of the Urethra (2). 
 
 Superior Layer of the Triangular Ligament (Urogenital diaphragm) (12). 
 
 Prostate Gland (part of the left lobe). 
 
 Neck of the Bladder (in part). 
 In Median Lithotomy, the incision, i}-^ inches long, is made transversely 
 
 through the central tendinous point and raphe, dividing the 
 Skin and Superficial Fascia. 
 
 Sphincter Ani Muscle (16) (some of its anterior fibres). 
 Branches of the Transverse Perinceal Vessels and Nerves. 
 Base of the Triangular Ligament (Urogenital diaphragm) (12). 
 
LITHOTOMY 3Q7 
 
 Membranous Portion of the Urethra (2). 
 Bulbo-Cavernosus (Compressor Urethra) Muscle. 
 
 Structures to be Avoided in Lithotomy. In the Lateral Operation 
 the structures to be remembered and avoided in making the incision are 
 the 
 
 Bulb, its Artery, and the Rectum, inwardly and in front; avoided by 
 not making the primary incision too near the middle line nor too far 
 forward. 
 
 Pudlc Artery di), externally; avoided by not carrying the incision too 
 far outwardly. 
 
 Prostrate Gland and Veins, behind; avoided by not carrying the deep 
 incision too far backward, so as to cut through the entire lobe of the 
 prostate gland, permitting the urine to infiltrate into the loose areolar 
 tissue around the rectum, instead of escaping externally. 
 

INDEX 
 
 ABDOMEN, 323 
 
 Regions of, 323 
 Abdominal Brain, 240 
 
 Cavity, 323 
 
 Openings of, 324 
 
 Rings, 385, 386 
 Acervulus Cerebri, 194 
 Acetabulum, 12 
 Achillis, Tendo, 113 
 Adenology, i 
 Ala Cinerea, 212 
 Ala Lobuli Centralis, 207 
 Alcock's Canal, 392 
 Alveoli, 3, 29, 33 
 
 of Lungs, 359 
 
 of Mammary Gland, 384 
 Amphiarthrosis, 59 
 Ampulla of Fallopian Tube, 382 
 
 of Milk Ducts, 384 
 
 of Semicircular Canals, 306 
 
 of Tubae Uterinae, 382 
 Amygdala, 207, 3M 
 Anastomosis, 145 
 
 Circumpatellar, 146 
 
 Crucial, 146 
 
 Elbow, 145 
 
 Hip, 145 
 
 Knee, 146 
 
 Shoulder, 145 
 
 Stirrup, 145 
 
 Tonsillar, 314 
 
 of Willis, 128, 151 
 Anatomy, i 
 Angiology, i 
 Angle, Filtration, 287 
 
 of Iris, 287 
 
 of Jaw, 35 
 Ankle-joint, 71 
 Annulus, Ciliaris, 146 
 
 Femoralis, 389 
 
 Fibrosus Sinister, 121 
 
 Inguinalis Abdominalis, 385 
 Subcutaneous, 386 
 
 Ovalis, 119 
 Anterior Extension (ischio-rectal fossa), 
 
 393 
 
 Anti-helix, 297 
 Anti-tragus, 297 
 Antrum of Highmore, 27 
 
 Mastoideum, 301 
 
 Tympanicum, 301 
 Anus, 335 
 Aorta. 123 
 
 Abdominal, 137. 156 
 
 Arch of, 123, 449 
 
 Thoracic, 136, 154 
 
 Aortic Bodies, 345 
 
 Apertura Pyraformis, 44 
 
 Apertures in Abdominal Wall, 324 
 
 Apex Capituli, 55 
 
 Appendices Epiploicae, 328, 335 
 
 Testis. 373 
 Appendix Auriculae, 119 
 
 Ensiform, 8 
 
 Ventriculae, 354 
 
 Vermiform, 334 
 
 Xiphoid, 8 
 Aponeuroses, 74 
 Aponeurosis, Pharyngeal, 322 
 
 Vertebral, 90 
 Apophysis, 3 
 
 Aquaeduct of Sylvius, 202 
 Aquaeductus Cerebri, 202 
 
 Cochleae, 21, 43, 306 
 
 Fallopii, 220, 225 
 
 Vestibuli, 21, 42, 305 
 Arachnoid of Brain, 181 
 
 of Cord, 213 
 
 Granulations, 181, 182 
 Arbor Vitae, 208, 380 
 Arch, Carpal, 135 
 
 Crural, 387, 39O 
 
 Glosso-palatine, 314 
 
 Lumbo-costal, 107 
 
 Palmar, 135 
 
 Pharyngo-palatine, 314 
 
 Plantar, 145 
 
 Superciliary, 14 
 
 Volar, 135 
 Arcuate Fibres, Cerebellar, 208 
 
 Medullary, 210 
 Area Cribrosa, 311 
 
 n. Facialis, 311 
 
 Vestibularis, 311 
 Areola Mammae, 384 
 Arm, 47 
 Arnold's Ganglion, 224 
 
 Nerve, 221, 250 
 Arterias Cavernosae, 127 
 
 Propriae Renales, 362 
 
 Receptaculi, 127 
 Arterial Anastomoses, 145 
 
 System Tabulated, 147 
 Arteriolae Rectae, 362 
 Artery or Arteries, 122, 147 
 
 Acromio-trmracic, 132, 153 
 
 Alar-thoracic, 132, 153 
 
 Alveolar, Inferior, 126, 150 
 Superior, 126, 150 
 
 Anastomoses of, 145 
 
 Anastomotica Magna (arm) , 133. 1 53 
 (thigh), 142, 1 60 
 
 399 
 
400 
 
 INDEX 
 
 Artery, Angular, 125, 148 
 of Ankle-joint, 71 
 Anonyma, 124, 148 
 Antero-lateral Ganglionic, 127, 151 
 Antero-medial Ganglionic, 127, 151 
 Aorta, 123 
 
 Abdominal, 137, 156 
 
 Arch of, 123, 148 
 
 Thoracic, 136, 154 
 Arch, Palmar (volar), Deep, 136, 
 
 153 
 Superficial, 135, 154 
 
 Plantar, 145, 162 
 Arcuata, 144, 162 
 Ascending Pharyngeal, 125, 150 
 of Auditory Canal, 298 
 Auditory, Internal, 312 
 of Auricle, 298 
 Auricular, 125, 148 
 
 Anterior, 126, 150 
 
 Deep, 126, 150 
 Posterior, 125, 150 
 Axillary, 132, 153 
 Axis, Coeliac, 137, 156 
 
 Thyroid, 131, 152 
 Azygos of Knee, 143, 162 
 
 of Vagina, 139, 379 
 Basal, 127 
 
 Basilar, 131, 151, 152 
 of Bladder, 368 
 Brachial, 133, 136, 153 
 of Brain, Cortical, 128 
 of Bones, 4 
 
 Bronchial, 136, 154, 356 
 Buccal, 126, 150 
 Bulbar, 131, 152 
 Bulbi Urethras, 140, 158 
 Calcanean, 144, 162 
 Canalis Pterygoidea, 126, 150 
 Carotid, Common, 124, 148, 150 
 
 External, 125, 148, 150 
 
 Internal, 126, 151 
 Carotico-tympanic, 127, 151 
 Carpal, Arch, Anterior, 135 
 Posterior, 135 
 
 Radial, Anterior, 133, 153 
 Posterior, 134, 153 
 
 Ulnar, Anterior, 135, 154 
 
 Posterior, 135, 154 
 Cavernosae, 127, 151 
 Centralis Retinas, 127, 289 
 Cerebellar, Anterior-inferior, 131, 
 152 
 
 Posterior-inferior, 131, 152 
 
 Superior, 131, 152 
 Cerebral, Anterior, 127, 151 
 
 Middle, 127, 151 
 
 Posterior, 128, 152 
 Cervical, Ascending, 131, 152 
 
 Deep, from Sup. Intercostal, 132 
 
 Superficial, 131, 152 
 
 Transverse, 131, 152 
 Choroid, Anterior, 128, 151, 283 
 
 Posterior, 128, 152 
 Ciliary, Anterior, 127, 290 
 
 Long, 127, 290 
 
 Short, 127, 290 
 Circle of Willis, 128, 151 
 
 Artery, Circulus Major and Minor, 285 
 Circumflex, Femoral, Lateral, 142, 
 
 160 
 Medial, 142, 160 
 
 Humeral, Anterior, 133, 153 
 Posterior, 133, 153 
 
 Iliac, Deep, 141, 160 
 Superficial, 141, 160 
 
 Scapulae, 132, 153 
 Coccygeal, 140, 158 
 Cochlear, 312 
 Coeliac Axis, 137, 156 
 Colic, Left (sinistra), 138, 156 
 
 Middle (media), 138, 156 
 
 Right (dextra), 138, 156 
 Comes Nervi Ischiadici, 140, 158 
 
 Phrenici, 132, 152 
 Communicating, Cerebral, Ante- 
 rior, 127, 152 
 Posterior, 127, 151 
 
 of Palmar Arches, 135, 154 
 
 of Plantar Arch, 144, 162 
 Coronary, of Heart, 123, 148 
 
 of Lips, 125, 148 
 of Corpus Cavernosum, 130, 158 
 Cortical System of Brain, 128 
 Cremasteric, 141, 160 
 Cricq-thyro'd, 125, 148 
 Cystic, 138, 156 
 Dental, Inferior, 126, 150 
 
 Superior, 126, 150 
 Digital, Palmar Collateral, 135, 154 
 
 Plantar Collateral, 145, 162 
 Dorsalis Clitoridis, 140, 158 
 
 Hallucis, 144, 162 
 
 Indicis, 134, 153 
 
 Linguae, 125, 148 
 
 Nasi, 127, 151 
 
 Pedis, 143, 162 
 
 Penis, 140, 158 
 
 Pollicis, 134, 153 
 
 Scapulae, 132, 153 
 of Ear, 301, 312 
 of Elbow, 66, 145 
 Epigastric, Deep, 140, 160 
 
 Inferior, 140, 160 
 
 Superficial, 141, 160 
 
 Superior, 132, 152 
 Ethmoidal, Anterior, 127, 151 
 
 Posterior, 127, 151 
 of Eustachian Tube, 304 
 of Eye, 289 
 Facial, Deep, 126, 151 
 
 Superficial, 125, 148 
 
 Transverse, 126, 150 
 Femoral, Common, 141 
 
 Deep (profounda), 142, 160 
 
 Superficial, 141, 160 
 Fibular, 144, 162 
 of Foot, 143, 144 
 of Forearm, 133, 153 
 Frontal, from Ant. Cerebral, 127, 151 
 Mid. Cerebral, 127, 151 
 Ophthalmic, 127, 151 
 Temporal, 126, 150 
 Ganglionic, Antero-lateral, 127, 151 
 
 Postero-lateral, 128, 152 
 
 Antero-medial, 127,151 
 
INDEX 
 
 4OI 
 
 Artery, Ganglionic, Postero-medial, 128, 
 152 
 
 System of Brain, 128 
 Gastric, 137, 150 
 Gastric, Left, 137, 156 
 
 Right, 137, 156 
 Gastricae Breves, 138, 156 
 Gastro-duodenal, 137, 156 
 Gastrp-epiploica Dextra, 137, 156 
 
 Sinistra, 138, 156 
 Genu Suprema, 142, 160 
 Gluteal, Inferior, 140, 158 
 
 Superior, 140, 160 
 Haemprrhoidal, Inferior, 140, 158 
 
 Middle, 139, 158 
 
 Superior, 138, 156 
 of Hand, 135 
 of Head, 124 
 of Heart, 119 
 Helicine, 371 
 Hepatic, 137, 138, 158, 340 
 
 Left, 138, 156 
 
 Right, 138, 156 
 of Hip-joint, 68, 145 
 Hyoid, from Lingual, 125, 148 
 
 from Superior Thyroid, 125, 148 
 Hypogastric, 139, 158, 160 
 Ileo-colic, 138, 156 
 Iliac, Circumflex, Deep, 141, 160 
 Superficial, 141, 160 
 
 Common, 139 
 
 External, 140, 160 
 
 Internal, 139, 158, 160 
 Ilio-lumbar, 140, 160 
 Incisor, 126, 150 
 Infra-orbital, 126, 150 
 Innominate, 124, 148 
 Intercostal, 136, 154 
 
 Anterior, 132, 152 
 
 Perforating, 132, 152 
 
 Superior, 132 
 
 Intercostalis Suprema, 132 
 Internal Auditory, 312 
 Interosseous, Common, 134 
 
 of Foot, 144, 162 
 
 of Forearm, 134, 154 
 
 of Hand, 134, 152 
 
 Ulnar, 134, 154 
 Intestines, 333, 336 
 Intestini Tenuis, 138, 156 
 of Iris, 285 
 of Kidney, 364 
 of Knee, 69, 143, 145, 162 
 Labial, Coronary, 125, 148 
 
 Inferior, 125, 148 
 Labiales, 125 
 of Labyrinth, 312 
 Lacrimal, 127, 151 
 Laryngeal, Inferior, 131, 152 
 
 Superior, 125, 148 
 of Larynx, 354 
 Lateralis Nasi, 125, 148 
 Lenticulo-striate (ant.-lat. gang- 
 
 lionic), 127 
 Lienal, 138, 156 
 Lingual, 125, 148 
 
 Dorsal, 125, 148 
 of Liver, 341 
 20 
 
 Artery, of Lower Extremity, 141 
 Lumbar, 138, 156, 160 
 of Lungs, 359 
 Magna, 153 
 Malleolar, Lateral, 143 
 
 Medial, 143 
 Mammary, External, 132 
 
 Internal, 131, 152 
 of Mammary Gland, 384 
 Mandibular (inf. dental), 126, 150 
 Masseteric, 126, 150 
 Mastoid, 125, 150 
 Maxillary, External, 125, 148 
 
 Internal, 126, 150 
 Median, 134 
 Mediastinal, 132, 152 
 
 Posterior, 136, 154 
 of Membrana Tympani, 299 
 Meningeal, Anterior, 127, 151 
 
 Middle, 126, 150 
 
 from Occipital, 125, 148 
 
 from Pharyngeal, 125, 150 
 
 Posterior, 131, 152 
 
 Small, 126, 150 
 
 from Vertebral, 131, 152 
 Mental, 126, 150 
 Mesenteric, Inferior, 138, 156 
 
 Superior, 138, 156 
 Metacarpal, 134, 153 
 Metatarsal, 144, 162 
 Musculo-phrenic, 132, 152 
 Mylo-hyoid, 126, 150 
 Nasal, Dorsal, 127, 151 
 
 Lateral, 125, 148 
 
 from Ophthalmic, 127, 151 
 of Nasal Fossae, 279 
 of Neck, 124 
 of Nose, 279 
 Nutrient of Clavicle, 131, 152 
 
 of Femur, 142, 160 
 
 of Fibula, 144, 162 
 
 of Humerus, 133, 153 
 
 of Tibia, 144, 162 
 Obturator, 139, 158, 389 
 Occipital, 125, 148 
 CEsophageal, 131, 136, 152, 154 
 of (Esophagus, 323 
 Ophthalmic, 127, 151 
 Orbital, 127, 151 
 Ovarian, 138, 156 
 of Ovaries, 383 
 Palatine, Ascending, 125, 148 
 
 Descending, 126, 150 
 
 Inferior, 125, 148 
 
 Posterior, 126, 150 
 Palmar (volar) Arch, Deep, 136 
 
 Superficial, 135 
 Recurrent, 134, 153 
 Palpebral, 127, 151 
 of Pancreas, 344 
 Pancreaticae magnae, 138 
 
 Parvae, 138 
 
 Pancreatico-duodenal, Inferior, 
 138, 156 
 
 Superior, 137, 156 
 Parietal, 126, 151 
 Parieto- temporal, 127. 151 
 of Parotid Gland, 126, 316 
 
402 
 
 INDEX 
 
 Artery, of Pelvis, 139 
 of Penis, 372 
 
 Perforating, Anterior Intercostal, 
 132, 152 
 
 of Foot, 145, 162 
 
 of Hand, 134, 153 
 
 of Thigh, 142, 1 60 
 Pericardiac, 132, 152 
 Pericardia!, 136, 15,1 
 Pericardio-phrenic, 132 
 of Pericardium, 118 
 Perinaeal, Superficial, 140, 158 
 
 Transverse, 140, 158 
 of Perineum, 140 
 Peroneal (fibular), 144, 162 
 Pharyngeal, 125, 126, 150 
 
 Ascending, 125, 150 
 of Pharynx, 322 
 of Pia Mater, 182 
 Plantar, Lateral, 144, 162 
 
 Medial, 14.4, 162 
 Popliteal, 143, 162 
 Postero-lateral Ganglionic, 128, 152 
 Postero-medial Ganglionic, 128, 152 
 Prevertebral, 125, 150 
 Princeps Cervicis, 125, 148 
 
 Polhcis, 134, 153 
 Profunda Brachii, 133, 153 
 
 Cervicis, 132 
 
 Femqris, 142, 160 
 
 Inferior (arm), 133, 153 
 
 Penis, 140, 158 
 
 Superior (arm), 133, 153 
 of Prostate Gland, 370 
 Pterygoid, 126, 150 
 Pterygo-palatine, 126, 150 
 Pubic, 141, 160 
 Pudendal, 139, 158 
 Pubic, External, Deep, 142, 160 
 Superficial, 141, 160 
 
 Internal, 139, 158 
 Pulnumary, 122, 147 
 Pyloric, 137, 156 
 Radial, 133, 153 
 Radialis Indicis, 134, 153 
 Radial Recurrent, 133, 153 
 Ranine, 125, 148 
 Receptaculi, 127, 151 
 Recurrent, Palmar (volar), 134,153 
 
 Radial, 133, 153 
 
 Tibial, Anterior, 144, 162 
 Posterior, 144, 162 
 
 Ulnar, Anterior, 134, 154 
 Posterior, 134, 154 
 
 Volar (palmar), 134, 153 
 Renal, 138, 156 
 Rete Carpi Dorsale, 135 
 
 Volare, 135 
 of Retina, 286 
 Sacral, Lateral, 140, 160 
 
 Middle, 138, 156 
 Scapular, Circumflex. 132, 153 
 
 Dorsal, 132, 153 
 
 Posterior, 131, 152 
 
 Transverse, 131 
 Sciatic, 140, 158 
 of Shoulder-joint, 65, 145 
 Sigmoid, 138, 156 
 
 Artery, Spermatic, 138, 156 
 of Spermatic Cord, 377 
 Spheno-maxillary, 126, 150 
 Spheno-palatine, 126, 150 
 Spinal, Anterior, 131, 152 
 
 Lateral, 131, 152 
 
 Posterior, 131, 152 
 of Spleen, 349 
 Splenic, 138, 156 
 Sternal, 132, 152 
 Sterno-mastoid, 125, 148 
 of Stomach, 330 
 Stylo-mastoid, 125, 150 
 Subclavian, 130 
 Subcostal, 136 
 Sublingual, 125, i/>8 
 Submandibular, 125, 148 
 Submental, 125, 148 
 Subscapular, 132, 153 
 Superficialis Volas, 133, 153 
 Supra-orbital, 127, 151 
 Supra-renal, 138, 156 
 of Supra-renal Gland, 365 
 Supra-scapular, 131, 152 
 Sural, 143 
 
 Tables of the Arterial System, 147 
 Tarsal, 144 
 
 Temporal, Deep, Anterior, 126, 150 
 Posterior, 126, 150 
 
 Middle, 126, 150 
 
 Superficial, 126, 150 
 of Testicle, 375 
 of Thigh, 141, 1 60 
 Thoracalis Lateralis, 132 
 
 Suprema, 132 
 Thoracic, Acromio, 132, 153 
 
 Alar, 132, 153 
 
 Axis, 131, 153 
 
 Long, 132, 153 
 
 Superior, 132, 153 
 Thoraco-acromial, 132 
 of Thymus Gland, 346 
 Thyroid. Axis, 131 
 
 Inferior, 131, 152 
 
 Superior, 125, 148 
 of Thyroid Gland, 346 
 Thyroidea Ima, 124 
 Tibial, Anterior, 143, 16^ 
 
 Posterior, 144, 162 
 
 Recurrent, Anterior, 143, 162 
 
 Posterior, 143, 162 
 of Tongue, 275 
 Tonsillar, 125, 148 
 
 True, 314 
 of Tonsils, 314 
 of Trachea, 356 
 Tracheal, 131, 152 
 Transversalis Colli, 131, 152 
 
 Scapulae, 131 
 True Tonsillar, 314 
 Truncus Thyreo-cervicalis, 131 
 of Trunk, 136 
 Tympanic from Ascending 
 Pharyngeal, 125, 150 
 
 from Internal Carotid, 127, 151 
 
 Maxillary, 126, 150 
 of Tympanic membrane, 299 
 of Tympanum, 302 
 
INDEX 
 
 403 
 
 Artery, Ulnar, 134, IS4 
 
 Carpal, 134, 154 
 
 Collateral, 133 
 
 Interosseous, 134 
 
 Recurrent, Anterior, 134, 154 
 
 Posterior, 134, 154 
 of Upper Extremity, 130 
 Urethral, 140 
 Uterine, 139, 158 
 of Uterus, 382 
 of Vagina, 379 
 Vaginal, 139, 158 
 Vasa Brevia, 138, 156 
 
 Intestinales, 138 
 
 Intestini Tenuis, 138, 156 
 
 Vasorum, 122 
 of Vas Deferens, 139, 158 
 Vertebral, 131, 152 
 Vesical, Inferior, 139, 158 
 
 Middle, 139, 158 
 
 Superior, 139, 158 
 of Vesiculae Seminales, 377 
 Vidian, 126, 150 
 Volar, Superficial, 133, 153 
 Willis, Circle of, 128, 251 
 Zygomatico-orbital, 126 
 Arthrodial joints, 59 
 Articulations, 59 
 
 Acromio-clavicular, 65 
 Ankle, 71 
 
 Astragalo-navicular, 72 
 Atlanto-axial, 58 
 Atlanto-epistrophica, 61 
 Calcaneo-astragaloid, 72 
 Calcaneo-cuboid, 72 
 Calcaneo-navicular, 72 
 Carpal, 50, 67 
 Carpo-metacarpal, 68 
 Chondro-sternal, 62 
 Costo-chrondal, 62 
 Costo-transverse, 62 
 Costo-vertebral, 62 
 Elbow, 66 
 Hip, 68 
 Intercarpal, 67 
 Interchondral, 62 
 Knee, 69 
 
 Metacarpo-metacarpal, 68 
 Metatarso-metatarsal, 73 
 Motion in, 60 
 Occipito-atlantal, 62 
 Occipito-axial, 62 
 Phalangeal of Foot, 73 
 
 of Hand, 68 
 Pubic, 64 
 Radio-carpal, 67 
 Radio-ulnar, 66 
 Sacro-C9ccygeal, 63 
 Sacro-iliac, 64 
 Sacro-ischiatic, 64 
 Sacro- vertebral, 63 
 Scapulo-clavicular, 65 
 Shoulder, 65 
 Sterno-clavicular, 64 
 Structure of, 60 
 Tarsal, 57, 72 
 Tarso-metatarsal, 72 
 Ternporo-mandibular, 6q 
 
 Articulations, Tibio-fibular, 71 
 
 of the Trunk, 60 
 
 Vertebral, 61 
 Arytenoid Cartilages, 351 
 Astragalus (talus), 57 
 Atic, 300 
 Atlas, 6 
 Atrium Meatus Medii Nasi, 278 
 
 Tympani, 300 
 Auricle of Ear, 297 
 
 of Heart, 119 
 Auris Externa, 296 
 
 Interna, 304 
 
 Media, 300 
 Axis, 7 
 
 Caeliac, 137, 156 
 
 Thyroid, 131, 152 
 Axis-cylinders, 177 
 Axones, 177 
 Azygos, 3 
 
 BAND, Bellinger's, 285 
 
 Naso-labial, 78 
 Bartholin, Duct of, 317 
 
 Glands of, 378 
 Basal Ganglia, 179 
 Base of the Brain, 186 
 
 , of the Skull, 41 
 Basi-hyal, 41 
 
 Basis Pedunculi Cerebri, 195 
 Bauhin, Valve of, 334 
 Bell, Sir Charles, Nerve of, 229, 256 
 Bertin, Columns of, 361 
 Bladder, Gall, 193 - *J f J 
 
 Urinary, 365 
 Blandin, Glands, of, 274 
 Blastema, 4 
 
 Blood- vascular System, 118 
 Body or Bodies, Aortic, 345 
 
 Carotid, 345 
 
 Chromaphil, 345 
 
 Ciliary, 283 
 
 Coccygeal, 349 
 
 Gemculate, 193 
 
 Malpighian, 349, 361 
 
 Mammillary, 188 
 
 Olivary, 209 
 
 Perinseal, 395 
 
 Pineal, 194 
 
 Pituitary, 186 
 
 Quadrigeminal, 202 
 
 Restiform, 207, 209 
 
 Vitreous, 287 
 
 Wolffian, 383 
 Bone or Bones, i 
 
 Astragalus (talus), 57 
 
 Atlas, 6 
 
 Axis (epistropheus), 6 
 
 Calcaneus, 57 
 
 Cancellous Bones, 2 
 
 Capitate (Magnum), 51 
 
 Cavities of, 3 
 
 Clavicle, 45 
 
 Classification of, i 
 
 Coccyx, ii 
 
 Composition of, 3 
 
 Costae, 8 
 
 Coxae or Coxal , 1 1 
 
404 
 
 INDEX 
 
 Bones, Cuboid, 57 
 
 Cuneiform (carpal), 51 
 
 (tarsal), 57 
 Eminences of, 3 
 Enumeration of, i 
 Epistrqpheus (axis), 6 
 Ethmoid, 26 
 Femur, 52 
 Fibula, 55 
 Flat Bones, 2 
 Frontal, 14 
 
 Hamate (unciform), 51 
 Histology of Bone, 3 
 Humerus, 47 
 Hyoid, 41 
 Ilium, 13 
 Incus, 301 
 
 Innominate (coxal), II 
 Irregular Bones, 2 
 Ischmm, 13 
 Lacrimal, 29 
 Long Bones, i 
 Lunate (Semilunar), 51 
 Malar, 30 
 Malleus, 301 
 Mandible, 33 
 Marrow of Bones, 4 
 Maxilla, 27 
 Medullated Bones, i 
 Metacarpals, 51 
 Metatarsals, 58 
 Multangular, Great, 51 
 
 Small, 51 
 Nasal, 27 
 Navicular (carpal), 51 
 
 (tarsal), 57 
 Occipital, 17 
 Orbicular, 301 
 Os Calcis, 57 
 Os Capitatum, 51 
 Os Coccygis, 1 1 
 Os Coxae, n 
 Os Hamatum, 51 
 Os Innominatum, n 
 Os Lunatum, 51 
 Os Magnum, 51 
 Os Multangulum Majus, 51 
 
 Minus, 51 
 Os Nayiculare, 51 
 Os Orbiculare, 301 
 Os Triquetrum, 51 
 Ossa Suturarum, 40 
 Ossification of Bones, 4 
 Palate, 31 
 Parietal, 16 
 Patella, 54 
 Pectineal, 14 
 Peroneal, 55 
 Petro-mastoid, 19 
 Phalanges of Foot, 58 
 
 of Hand, 52 
 Pisiform, 51 
 
 Prominences of Bones, 3 
 Pubic, 14 
 Radius, 49 
 Ribs (costse), 18 
 Sacral, 10 
 Scaphoid (carpal), 51 
 
 Bones, Scaphoid (tarsal), 57 
 
 Scapula, 45 
 
 Semilunar, 51 
 
 Sesamoid, 3 
 
 Short Bones, i 
 
 Squamous, 19 
 
 Stapes, 301 
 
 Sternum, 8 
 
 Structure of Bone, 4 
 
 Talus, 57 
 
 Temporal, 19 
 
 Tibia, 54 
 
 Trapezium, 51 
 
 Trapezoid, 51 
 
 Triquetral (cuneiform), 51 
 
 Turbinal, 32 
 
 Tympanic, 19 
 
 Ulna, 48 
 
 Unciform, 51 
 
 Unclassified Bones, 3 
 
 Vertebrae, 5 
 
 Vomer, 33 
 
 Wormian, 3, AO 
 
 Zygomatic, 30 
 Bowman's Capsule, 361 
 
 Glands, 279 
 
 Muscle (ciliary), 284 
 
 (cochlear), 309 
 Brachia Conjunctiva, 201, 207 
 
 Pontis, 204, 207 
 Brain, 178 
 
 Abdominal, 240 
 
 Basal Ganglia of, 179 
 
 Cerebellum, 206 
 
 Cerebrum, 183 
 
 Convolutions of, 185 
 
 Cortex of, 179 
 
 Development of, 178 
 
 Diencephalon, 178 
 
 Divisions of, 178, 182 
 
 Fissures of, 184 
 
 Gray Matter of, 179 
 
 Hind-brain, 203 
 
 Hypophysis Cerebri. 186 
 
 Island of Reil, 183 
 
 Isthmus Cerebri, 194 
 
 Isthmus Rhombencephali, 178, 203 
 
 Lobes of, 183 
 
 Medulla Oblongata, 208 
 
 Meninges of, 180 
 
 Mesencephalon, 178, 194 
 
 Metencephalon, 178, 203 
 
 Mid-brain, 178, 194 
 
 Myelencephalon, 178, 208 
 
 Points on Under Surface, 186 
 
 Pons Varolii, 203 
 
 Prosencephalon, 178 
 
 Rhombencephalon, 192 
 
 Telencephalon, 178 
 
 Thalamencephalon, 192 
 
 Under Surface of, 186 
 
 Weight of Average Brain, 182 
 
 White Matter of, 179 
 
 Ventricles of, 189 
 
 Vesicles of, 178 
 Breasts, 383 
 
 Broca's Area or Convolution, 185 
 Bronchi, 355 
 
INDEX 
 
 405 
 
 Bruch's Membrane, 283 
 
 Brunner's Glands, 333 
 
 Buccae, 312 
 
 Buck's Fascia, 393 
 
 Buds, Taste, 274 
 
 Bulb of Corpus Spongiosum, 372 
 
 Olfactory, 183 
 
 Spinal, 208 
 
 Urethra], 369 
 Bulbus Oculi, 280 
 
 Vestibuli, 378 
 Bulla Ethmoidalis, 277 
 Bundle, Ground, 215 
 
 Posterior Longitudinal, 200 
 Burns' Ligament, 390 
 Bursa Omentalis, 325 
 
 Pharyngea, 321 
 Bursae of Knee-joint, 71 
 
 Calamus Scriptorius, 211 
 
 Calcaneus, 57 
 
 Calcar Avis, 191 
 
 Calcar Femorale, 53 
 
 Calices of Kidney, 361 
 
 Cameras Oculi, 287 
 
 Camper's Fascia, 108, 385 
 
 Canal, or Canalis, Adductor, no, 142 
 
 Alcock's, 392 
 
 Alimentary, 312 
 
 Anal, 335 
 
 of Arnold's Nerve, 21 
 
 Carotid, 20 
 
 Central of the Cord, 214 
 
 Centralis Modioli, 306 
 
 Cervicis Uteri, 380 
 
 Condyloideus Posterior, 18 
 
 Crural, 388 
 
 Dental, 27 
 
 Facial, 220, 225 
 
 Femoral, 388 
 
 Haversian, 4 
 
 of Huguier, 19 
 
 Hunter's, no, 142 
 
 Hyaloid, 288 
 
 Hypoglossi, 1 8 
 
 Infra-orbital, 28 
 
 Inguinal, 385 
 
 of Jacobson's Nerve, 21 
 
 Lacrimal, 295 
 
 of Laxator Tympani, 19, 43 
 
 Malar, 30, 36 
 
 Mandibular, 34 
 
 of the Modiolus, 306 
 
 of Nuck, 381 
 
 Palatine, 28 
 
 Petit's, 288, 289 
 
 Pharyngeal, 32 
 
 Pterygoideus, 25 
 
 Ptery go-palatine, 28 
 
 Reuniens, 307, 308 
 
 Sacral, n 
 
 of Schlemm, 282 
 
 Semicircular, 305, 308 
 
 Spheno-palatine, 32 
 
 Spiral of Cochlea, 306 
 
 Stilling's, 288 
 
 for Tensor Tympani, 301 
 
 Canal, Vidian, 25 
 
 Zygomatico-facial, 30, 36 
 
 Zygomatico-temporal, 36 
 Canaliculi Dentales, 319 
 
 Lacrimal, 295 
 Canthus (eye), 293 
 Capillaries, Biliary, 340 
 
 Blood, 122 
 
 Capitellum Humeri, 48 
 Capsule or Capsula, Bowman's, 361 
 
 External, 192 
 
 of Glisson, 340 
 
 Glomeruli, 361 
 
 Internal, 192 
 
 Lentis, 288 
 
 Tenon's, 280 
 
 Supra-renal, 364 
 Caput Gallinaginis, 368 
 Cardia, 329 
 Carpus, 50 
 Cartilage or Cartilage, 60 
 
 Arytenoid, 351 
 
 Corniculata, 352 
 
 Cricoid, 351 
 
 Cuneiform, 352 
 
 Epiglottica, 352 
 
 of Larynx, 350 
 
 Santorini's, 352 
 
 Thyroid, 350 
 
 Triticea, 353 
 
 Varieties of, 60 
 
 Wrisberg's, 352 
 Carunculae Humenales, 378 
 
 Lacrimal, 295 
 
 Myrtiformes, 378 
 Cauda Equina, 216 
 Cavity or Cavum 
 
 Abdominal, 323 
 
 Acetabular, 12 
 
 Cotyloid, 12 
 
 Dentis, 318 
 
 Glenoid, 47 
 
 Omental, 325 
 
 Oris, 312 
 
 Pelvic, 391 
 
 Peritonaei, 325 
 
 Pulp, 318 
 
 Septi Pellucidi, 191 
 
 Sigmoid of Radius, 50 
 of Ulna, 49 
 
 Subarachnoidalis, 181 
 
 Subdurale, 181 
 
 Tympanic, 300 
 
 Uteri, 380 
 Cells, Air, 359 
 
 Auditory, 310 
 
 Claudius', 310 
 
 Deiters', 310 . 
 
 Ethmoidal, 26 
 
 Golgi's, 176, 208 
 
 Hair, 307, 310 
 
 Hensen's, 310 
 
 Hepatic, 340 
 
 Mastoid, 20 
 
 Nerve, 176 
 
 Olfactory, 278 
 
 Purkinje's, 176, 208 
 
 Reticular, 349 
 
406 
 
 INDEX 
 
 Cells, Sustentacular, 349 
 
 Cement, 319 
 
 Cerato-hyal, 41 
 
 Cerebellum, 206 (see Brain) 
 
 Cerebro-spinal System, 175 
 
 Cerebrum, 179 (see Brain) 
 
 Cervic Penis, 372 
 
 Cervix Uteri, 380 
 
 Chambers (camerae) of the Eye, 287 
 
 Chiasm, Optic, 292 
 
 Chorda Tympani, 220, 248, 276 
 
 Chordae Tendinae, 120 
 
 Choroid, 283 
 
 Plexus, 190, 211 
 Chromaffin System, 344 
 Chromaphil System, 344 
 Cilia, 293 
 Ciliary Body, 283 
 Cingulum, 180 
 Circle of Willis, 128, 151 
 Circulation, Collateral, 146 
 Circulus Major of Iris, 285 
 
 Minor of Iris, 285 
 
 Venosus, 384 
 Cisterna Chyli, 172 
 
 Cerebello-medullaris (magna), 182 
 
 Inter-peduncularis, 182 
 
 Magna (cerebello-medullaris) , 182 
 Clarke's Column, 210, 216 
 Claudius' Cells, 310 
 Claustrum, 192 
 Clava, 198 
 Clavicle, 45 
 Clinoid, 3 
 Clitoris, 378 
 Clivus Monticuli, 207 
 Cloquet's Fascia, 389 
 Coccygis, ii 
 Coccyx, ii 
 Cochlea, 306, 309 
 Collar-bone, 45 
 Collateral Circulation, 146 
 Colics' Fascia, 392 
 Colliculi (quadrigemina), 202 
 Colliculus Nervi Facialis, 212 
 Optici, 286 
 
 Semmalis, 368 
 Colloid, 346 
 Collum Glandis, 372 
 Colon, 334 
 Column or Columns 
 
 Antero-lateral of Cord, 214 
 
 Bertin's, 361 
 
 Burdach's, 198, 210, 215 
 
 Clarke's, 210, 216 
 
 Coil's, 198, 210, 215 
 
 Lateral of Medulla, 209 
 
 Posterior of Cord, 214 
 Vesicular (Clarke's), 216 
 
 Postero-lateral of Cord, 214 
 
 Postero-median of Cord, 214 
 
 of Spinal Cord, 213 
 
 of Vagina, 379 
 Columnae Carneae, 120, 122 
 
 Rugarum, 379 
 Commissura or Commissure 
 
 Anterior (yhite) of 3d Ventricle, 
 192 
 
 Commissura, Gray (middle) of 3d Ven- 
 tricle, 193 
 
 Gudden's, 194, 292 
 
 Labiorum Pudendi, 377 
 
 Meynert's, 292 
 
 Middle (gray) of 3d Ventricle, 193 
 
 Optic, 1 86, 292 
 
 Palpebrarum, 293 
 
 Posterior (white) of 3d Ventricle, 193 
 Concha or Conchae 
 
 Auriculas, 297 
 
 Nasalis, 26, 32 
 
 Sphenoidal, 24 
 Conductor Sonorus, 212 
 Condyle, 3 
 
 Condyloid Articulations, 59 
 Confluens Sinuum, 165 
 Coni Vasculosi, 374 
 Conjoined Tendon, 95 
 Conus Arteriosus, 120 
 
 Elasticus, 353 
 Convolution of Broca, 185 
 Convolutions of the Cerebrum, 185 
 Cooper's (Sir Astley) Fascia, 390 
 Cor, 118 
 Coracoid, 3 
 Cord, Gangliated, 237 
 
 Spermatic, 376 
 
 Spinal, 213 
 .Vocal, 353 
 Conum, 270, 271 
 Cornea, 282 
 
 Cornicula Laryngis, 352 
 Cornua of Hyoid, 41 
 
 Uteri, 380 
 
 Ventricular, 190 
 Corona Glandis, 372 
 
 Radata, 196 
 Coronoid, 3 
 Corpora Albicantia, 188 
 
 Amylacea, 194 
 
 Cavernosa, 371 
 
 Geniculata, 193 
 
 Mammillaria (albicantia), 188 
 
 Quadrigemina (colliculi), 202 
 
 Restiformes, 207, 209 
 Corpus Albicans, 383 
 
 Callosum, 190 
 
 Cayernosum Urethras, 371 
 
 Ciliare, 283 
 
 Dentatum, 209 
 
 Fimbriatum, 190, 191 
 
 Highmorianum, 374 
 
 Luteum, 383 
 
 Mammae, 384 
 
 Medullare, 206 
 
 Pineale, 194 
 
 Striatum, 191 
 
 Trapezoideum, 204 
 
 Uteri, 380 . 
 
 Vitreum, 287 
 Corpuscles, Cprneal, 282 
 
 Ganglionic, 176 
 
 Pacinian, 272 
 
 Tactile, 272 
 Cortex, Cerebellar, 208 
 
 Cerebral, 179 
 
 Renal, 361 
 
INDEX 
 
 407 
 
 Corti, Organ of, 309 
 Cortical System, 345 
 Costae (ribs), 8 
 Cotyloid. 3 
 
 Cavity, 12 
 
 Notch, 12 
 Coverings of Brain, 180 
 
 of Femoral Hernia, 390 
 
 of Inguinal Hernia, 388 
 
 of Testicles, 373 
 
 of Spinal Cord, 213 
 Cowper's Glands, 371 
 Coxal or Hip-bone, n 
 Crest, Conchal, 27, 31 
 
 of Ilium, 13 
 
 Infra-temporal, 24 
 
 Inter-trochanteric, 53 
 
 Nasal, 29 
 
 Nuchal, 17 
 
 of Pubis, 17 
 
 Sphenoidal, 23 
 
 Tibial, 55 
 
 Turbinal, 27, 31 
 Cribriform Fascia, 108, 390 
 
 Plate, 26 
 
 Cricoid Cartilage, 351 
 Crista Falciformis, 311 
 
 Galli, 26 
 
 Transversa, 311 
 
 Urethrae, 368 
 
 Vestibuli, 305 
 Crucial Anastomosis, 146 
 
 Ridge, 1 8 
 Crura of Abdominal Ring, 386 
 
 Cerebri, 195 
 
 Clitoridis, 378 
 
 of Diaphragm, 95 
 
 of Penis, 371 
 Crus Commune, 306 
 Crusta Cerebri, 195 
 
 Petrosa, 319 
 
 Crypts, of Lieberkuhn, 332 
 Cuboid, 57 
 
 Culmen Monticuli, 207 
 Cuneus, 186 
 Cupola Cochleae, 306 
 Cushion, Pharyngeal, 321 
 Cuticle, 268 
 Cuticuta Dentis, 319 
 Cutis Vera, 270 
 
 DARTOS, 373 
 
 Darwin's Tubercle, 297 
 
 Decussation, Inferior Pyramidal, 209 
 
 Motor, 209 
 
 Sensory, 198 
 
 Superior Pyramidal, 198 
 Deiter's Cells, 310 
 Dendrites, 177 
 Dentes, 317 
 Dentine, 318 
 Derma, 270 
 Dermatology, I 
 Descemet's Membrane, 282 
 Diaphragm, 94 
 
 Urogenital, 393 
 Diaphragma Sellae, 181 
 Diaphysis, 9 
 
 Diarthrosis, 59 
 Diclive, 207 
 Diencephalon, 178, 192 
 Discus Proligerus, 383 
 Disk, Intervertebral, 61 
 
 Optic, 286 
 Diverticulum Ilei, 331 
 
 Meckel's, 331 
 Dollinger's Band, 285 
 Dorsum Sellae, 23 
 Douglas' Pouch, 327 
 
 Semilunar Fold, 96 
 Drum of the Ear, 300 
 Drum-head, 298 
 Duct, Ducts, or Ductus 
 
 Aberrans, 373 
 
 Arteriosus, 123 
 
 Bartholin's, 317 
 
 Biliary, 342 
 
 Cochlearis, 307 
 
 Communis Choledochus, 342 
 
 Cowper's, 368 
 
 Cystic, 343 
 
 Deferens, 375 
 
 Ejaculatory, 368, 376 
 
 Endo-lymphaticus, 308 
 
 Gartner's, 383 
 
 Hepatic, 342 
 
 Lactiferi, 384 
 
 Lymphatic, 172 
 
 Lymphaticus Dexter, 172 
 
 Nasal, 28, 296 
 
 Naso-lacrimal, 296 
 
 Pancreatic, 344 
 
 Parotideus, 316 
 
 Prostatic, 370 
 
 Rivinius", 316 
 
 Santorini's, 344 
 
 Semicirculares, 307, 308 
 
 Stenson's, 316 
 
 Sublinguales Minores, 316 
 
 Sublingualis, 316 
 
 Submaxillaris, 316 
 
 Thoracic, 172 
 
 Wharton's, 316 
 
 Wirsung's, 344 
 
 Utriculo-saccularis, 308 
 Ductless Glands, 344 
 Duodenum, 331 
 Dural Sinuses, 164, 165 
 Dura Mater Cerebri, 180 
 Spinalis, 213 
 
 EAR, 296 
 
 External, 297 
 
 Internal, 304 
 
 Middle, 300 
 Elbow-joint, 66 
 Eleidin, 270 
 Eminence, Frontal, 14 
 
 Hypothenar, 106 
 
 Malleolar, 298 
 
 Nasal, 14 
 
 Eminence Parietal, 16 
 
 Pectineal, 14 
 
 Thenar, 196 
 Eminentia Articularis, 19 
 
 Cinprea . v i 
 
INDEX 
 
 Eminentia Collateralis, 191 
 
 Inter-cpndyloidea, 54 
 
 Pyramidalis, 301 
 
 Saccularis, 186 
 
 Teres, 212 
 Enamel, 319 
 Enarthrosis, 59 
 End-bulbs of Krause, 177, 272 
 Endocardium, 118 
 Endolymph, 304 
 Endomysmm, 74 
 Endoneurium, 177 
 End-organs of Nerves, 177 
 Endosteum, 4 
 Ensiform (xyphoid), 8 
 Epidermis, 270 
 Epididymis, 373 
 Epigastric Region, 324 
 Epiglottis, 352 
 Epineurium, 177 
 Epiphysis, 3 
 
 Cerebri, 194 
 
 Epistropheus (axis), 6, 7 
 Equilibration, Organ of, 309 
 Ethmoid, 26 
 Eustachian Tube, 303 
 Eye, 280 
 
 Eyebrows, 293 
 
 Eyelashes, 293 
 
 Eyelids, 293 
 
 Eye-socket (orbit), 35 
 
 Excavatio Papillae Nervi Optici, 286 
 
 Recto-uterina, 327 
 
 Recto- vesicalis, 327 
 
 Vesico-uterina, 327 
 Extension, Anterior of Ischio-rectal 
 Fossa, 394 
 
 FACET, 3 
 
 Fallopian Tubes, 382 
 
 Fallopius, Aquseduct of, 220, 225 
 
 Hiatus of, 20 
 Falciform Process, 390 
 Falx Aponeurotica Inguinalis, 95 
 
 Cerebelli, 181 
 
 Cerebri, 181 
 Fascia, Anal, 392 
 
 Bicipital, 133 
 
 Buck's, 393 
 
 Bulbi Oculi, 280 
 
 Camper's, 108, 385 
 
 Cloquet's, 389 
 
 Colles', 392 
 
 Cooper's, 390 
 
 Cremasteric, 386 
 
 Cribriform, 108, 390 
 
 Deep, 74 
 
 Dentate, 191 
 
 Diaphragmatis Urogenitalis, 393 
 
 Dorsal, 90 
 
 Infundibuliform, 385 
 
 Iliac, 107 
 
 Intercolumnar, 386 
 
 Ischio-rectal, 392 
 
 Lata, 1 08, 199 
 
 Lumbar, 90 
 
 Fascia, Lumbo-dorsal, 90 
 Naso-labial Band, 78 
 Obturator, 391 
 Palmar, 105 
 Parotid, 315 
 
 Parotideo-masseteric, 315 
 Pelvic, 391 
 Perinaeal, Deep, 393 
 
 Superficial, 392 
 Pharyngo-basilar, 322 
 Plantar, 115 
 Recto- vesical, 391 
 Scarpa's, 108, 390 
 Spermatic, 386 
 Superficial, 74 
 Trartsversalis, 107, 390 
 Triangular, 387 
 Fasciae, 74 
 
 of the Back, 90 
 of the Foot, 115 
 of the Hand, 105 
 of the Pelvis, 391 
 of the Perinaeum, 392 
 of the Thigh, 108 
 Fasciculus, see also Tract 
 
 Anterior Cerebro-soplina, 96, 214 
 Cerebello-olivary, 211 
 Cerebro-spinalis Anterior, 196, 214 
 
 Lateralis, 196, 214 
 Crossed Pyramidal, 196, 214 
 Cuneatus (Burdach's), 198, 210, 215 
 Direct Cerebellar, 210 
 Direct Pyramidal, 196, 214 
 Dorsal Spino-cerebellar, 210 
 Fillet, 198 
 Flechsig's, 210 
 Geniculate, 196 
 Geniculate, 196 
 Gower's, 205 
 Gracilis (Coil's column), 198, 210, 
 
 215 
 
 Inferior Longitudinal, 180 
 Lateral Cerebro-spinal, 196, 214 
 
 Lemniscus, 199 
 Lemniscus, (fillet), 198 
 Medial Lemniscus, 198 
 
 Longitudinal, 200 
 Meynert's, 292 
 Olivary, 202 
 Olivo-cerebellar, 210 
 Perpendicular, 180 
 Posterp-lateral, 215 
 Proprii, 215 
 Proprius Anterior, 215 
 
 Dorsalis, 215 
 
 Posterior, 215 
 
 Ventralis, 215 
 
 Retroflexus (Meynert's), 29 
 Rolando's, 209 
 Rubro-Spinal, 201 
 Solitary, 211, 221 
 
 Spino-cerebellar, Anterior, 205, 210, 
 214 
 
 Dorsal, 210, 215 
 Sulco-marginal, 199 
 Superficial Ventro-lateral (Gower's) 
 
 295, 206 
 Superior Longitudinal, 180 
 
INDEX 
 
 409 
 
 Fasciculus, Teres, 205 
 
 Tri-neural, 211 
 
 Tiirck's, 196 
 
 Uncinate, 180 
 
 Ventral Cerebro-spinal, 196 
 
 Longitudinal, 199 
 Fauces, 314 
 Femur, 52 
 Fenestra Cochleae, 21, 300 
 
 Ovalis, 300 
 
 Rotunda, 300 
 
 Vestibuli, 21, 300 
 Ferrein's Pyramids, 362 
 Fibrae Propriae, 207 
 Fibres, Arcuate of Cerebellum, 208 
 of Medulla, 210 
 
 Association, 180 
 
 Commissural, 180 
 
 Medullated, 17? 
 
 Miiller's, 286 
 
 Nerve, 177 
 
 Non-medullated, 177 
 
 Peduncular, 179, 207 
 
 Projection, 179, 192 
 
 Transverse, 180 
 Fibro-cartilage, 60, 70 
 Fibula, 55 
 Fillet, Lateral, 199 
 
 Medial, 198 
 Filum Terminale, 213 
 Fimbria Ovarica. 382 
 Fimbriae Tubae Uterinas, 382 
 Fissure, Auricular, 21, 43 
 
 Ethmoidal, 41 
 
 Glaserian, 19, 43 
 
 Orbital, 25, 36, 39, 41 
 
 Palpebral, 293 
 
 Pterygo-maxillary, 39 
 
 Rolando's, 184 
 
 Sphenoidal, 25, 36, 41 
 
 Spheno-maxillary, 37, 39 
 
 Squamo-tympanic, 44 
 
 Sylvius', 184 
 Fissures of Cerebellum, 206 
 
 of Cerebrum, 184 
 
 of Liver, 337 
 
 of Spinal Cord, 213 
 Flexure, Sigmoid, 334 
 Flocculus, 207 
 Fluid. Cerebro-spinal, 182 
 Fold, Aryteno-epiglottidean, 352 
 
 Glosso-epiglottidean, 353 
 
 Palpebral, 295 
 
 Semilunar, 295 
 
 of Douglas, 96 
 Folium Cacuminis, 207 
 Folliciles, Hair, 271 
 
 Simple, 332, 335 
 Folliculi Oophori Vesiculosi, 383 
 Fontana's Spaces, 282 
 Fontanelles, 40 
 Foot, 56 
 Foramen for Arnold's Nerve, 21, 43 
 
 Caecum, 15, 43, 274 
 
 Carotid, 43 
 
 Condylar, 18, 42 
 
 Costo-transverse, 6 
 
 Epiploicum, 326 
 
 Foramen for Ethmoidal, 16, 37, 41 
 Incisive, 29, 42 
 Infraorbital, 28 
 Interventricular, 190 
 Intervertebral, 5 
 for Jacobson Nerve, 21, 43 
 
 Jugular, 42 
 of Ke 
 
 [ey and Retzius, 211 
 
 Lacerum Anterius, 25, 36, 41 
 Medium, 41 
 Posterius, 17, 42 
 
 Magendie's, 182, 211 
 
 Magnum, 17, 42 
 
 Mandibular, 34 
 
 Mastoid, 20, 42 
 
 Mental, 31 
 
 Munro's, 190 
 
 Obturator, 12 
 
 Olfactory, 38, 41 
 
 Ovale, 24, 41 
 
 Optic, 25, 37, 41 
 
 Orbital, 24 
 
 Palatine, 32, 42 
 
 Parietal, 16 
 
 Pterygo-palatine, 42 
 
 Rotundum, 24, 41 
 
 Sacral, n 
 
 Scarpa's, 29, 42 
 
 Singulare, 311 
 
 Spheno-palatine, 31 
 
 Spinal, 6 
 
 Spinosum, 24, 41 
 
 Stenson's, 29, 42 
 
 Stylo-mastoid, 21, 43 
 
 Supraorbital, 14 
 
 Suprascapular, 45 
 
 Thyroid, 12 
 
 Vertebrale, 6 
 
 Winslow's, 326 
 Foramina at the Base of the Skull, 41 
 
 Interventricularia, 190 
 
 Olfactory, 41 
 
 Orbital, 35 
 
 Spheno-maxillary, 42 
 
 Thebesii, 119 
 
 Venarum Minimarum, 119 
 Forearm, 48 
 
 Formatio Reticularis, 211 
 Fornix Cerebri, 190 
 
 Conjunctivas, 295 
 Fossa of the Auricle, 297 
 
 Canine, 28 
 
 Cochlearis (recessus), 305 
 
 C9ronoid, 48 
 
 Digastric, 20, 34 
 
 Digital (femoris), 53 
 (testis), 374 
 
 Duodenal, 327 
 
 Duodeno-jejunal, 327 
 
 Floccular, 22 
 
 Glenoid, 19 
 
 Hypophyses, 22 
 
 Ileq-colic, 328 
 
 Incisive, 28, 34 
 
 Incudis, 301 
 
 Infraspinous, 45 
 
 Inguinal, 388 
 
 Intercondylar, 55 
 
4io 
 
 INDEX 
 
 Fossa of the Intersigmoid, 328 
 
 Ischio-rectal, 394 
 
 Jugular, 1 8, 21 
 
 Lacrimal, 15, 36 
 
 Mandibular, 19 
 
 Nasal, 37, 277 
 
 Navicularis Auriculae, 297 
 Penis, 369 
 Pudendi, 377 
 
 Olecranon, 48 
 
 Ovalis Cordis, 108, 119 
 Femoralis, 389 
 
 Patellaris, 288 
 
 Pericascal, 328 
 
 Perinaeal, 393 
 
 Peritoneal, 327, 388 
 
 Pterygoid, 25 
 
 Radial, 48 
 
 Rosenmuller's, 322 
 
 Scaphoid, 25 
 
 Spheno-maxillary, 39 
 
 Spheno-palatine, 39 
 
 Sublingual, 34 
 
 Submandibular, 34 
 
 Subscapular, 45 
 
 Supraspinous, 45 
 
 Supra-tonsillaris, 314 
 
 Temporal, 38 
 
 Triangularis Auriculae, 297 
 
 Trochanteric, 53 
 
 Venae Cavae Hepatis, 338 
 
 Vesicae Felleae, 338 
 
 Zygomatic, 39 
 Fossae, Inguinal, 388 
 
 Nasal, 37, 277 
 
 Perinaeal, 393 
 
 Retro-peritoneal, 327 
 
 of the Skull, 41, 42 
 Fourchette, 377 
 Fovea Articularis, 6 
 
 Centralis, 285 
 
 Hemispherica, 305 
 
 Inferior of 4th Ventricle, 212 
 
 Semi-elliptica, 305 
 
 Superior of dth Ventricle, 212 
 Fraenulum Cerebelli, 207 
 
 Praeputii, 372 
 Fraenum Linguae, 223 
 Frenula Oris, 312 
 Frontal Bone, 14 
 
 Sinuses, 15 
 Fundus Oculi, 285, 286 
 
 Uteri, 380 
 
 Funiculus, Antero-lateral of Cord, 
 213 
 
 Cuneatus of Medulla, 210 
 
 Gracilis of Medulla, 210 
 
 Lateralis of Medulla, 209 
 
 Posterior of Cord, 213, 215 
 
 Postero-lateral of Cord, 214 
 
 Postero-median of Cord, 214 
 
 Rolando's, 209 
 
 Teres, 205 
 
 Solitarius, 211, 221 
 
 GALL-BLADDER, 343 
 Gartner's Duct, 383 
 Ganglia, 177 
 
 Ganglia, Basal, 179 
 
 Cervical, 237, 268 
 
 of the Cranial Nerves, 223 
 
 Lumbar, 238, 268 
 
 of Ninth Cranial Nerve, 226 
 
 Pelvic, 238 
 
 Sacral, 268 
 
 Semilunar, 240 
 
 Spinal, 216, 226 
 
 Sympathetic, 268 
 
 of Tenth Cranial Nerve, 226 
 
 Thoracic, 237, 268 
 
 Gangliated Cord of Sympathetic, 237 
 Ganglion, Arnold's, 224 
 
 Bochdalek's, 236 
 
 Cardiac of Wrisberg, 239 
 
 Carotid, 236 
 
 Cerebellar, 208 
 
 Ciliary, 224 
 
 Coccygeal, 238, 268 
 
 Cceliac, 240 
 
 Diaphragmatic, 240 
 
 Gasserian, 223 
 
 Geniculate, 225 
 
 Habenulae, 194 
 
 Impar, 236, 268 
 
 Inferius, 226 
 
 Jugular, 226 
 
 Jugulare, 226 
 
 Lenticular, 224 
 
 Meckel's, 224 
 
 Nodosum, 226 
 
 Ophthalmic, 224 
 
 Otic, 224 
 
 Petrous, 226 
 
 Ribes', 236, 237. 268 
 
 of Root of Tenth Nerve, 226 
 
 Scarpa's, 311 
 
 Semilunar, 223, 240 
 
 Spheno-palatine, 224 
 
 Spinal, 216 
 
 Spirale, 311 
 
 Submandibular, 225 
 
 Submaxillare, 225 
 
 Superius, 226 
 
 of Trunk of the Tenth Nerve, 226 
 
 Valentines', 236 
 
 Wrisberg's, 239 
 Gasser's Ganglion, 223 
 Genesiology, i 
 Geniculate Bodies, 193 
 Gimbernat's Ligament, 387 
 Gingivae, 317 
 Girdle, Pelvic, 44 
 
 Shoulder, 44 
 Gladiolus, 8 
 Gland or Glands 
 
 Adrenal, 364 
 
 Aortic Bodies, 345 
 
 Axillary, 173 
 
 Barth9lin's, 378 
 
 Blandin's, 274 
 
 Bowman's, 279 
 
 Bronchial, 175 
 
 Brunner's, 333 
 
 Bulbp-urethral, 371 
 
 Cardiac, 330 
 
 Carotid Bodies, 345 
 
INDEX 
 
 411 
 
 Giands of Chromaffin System, 344 
 of Chromaphil System, 344 
 Ciliary, 293 
 Coccygeal, 349 
 Cceliac, 174 
 
 of Cortical System, 345 
 Cowper's, 371 
 Ductless, 344 
 Duodenal, 333 
 Gastric, 329, 330 
 Glomus Caroticum, 345 
 
 Coccygeum, 349 
 Ebner's, 274 
 Entodermal, 345 
 Fundus, 330 
 Haemal, 172 
 
 Lymph, 172 
 Intestinal, 332, 335 
 Kidney, 360 
 Lacrimal, 295 
 Lien, 275 
 Littr6's, 369 
 Liver, 336 
 Lumbar, 174 
 Lymphatic, 171 
 Mammary, 383 
 Mediastinal, 175 
 Meibomian, 294 
 Mesenteric, 175 
 Moll's, 293 
 Mucous, 315 
 Nuhn's, 274 
 CEsophageal, 323 
 Ovary, 382 
 Pancreas, 343 
 Paraganglia, 345 
 Parathyroid, 346 
 Parovarium, 383 
 Partiod, 315 
 Peyer's, 333 
 Phaerochrome, 344 
 Pineal, 194 
 Pituitary, 186 
 Prostate, 370 
 Pyloric, 330 
 Racemose Serous, 274 
 Rosenmuller's, 295 
 Salivary, 315 
 Sebaceous, 271, 273 
 Seminal, 372 
 Serous, 274 
 Smegma, 372 
 Solitary, 333 
 Spleen, 375 
 Sublingual, 316 
 Submandibular, 316 
 Submaxillaris, 316 
 Sudoriferous, 271, 273 
 Supra-renal, 364 
 Sweat, 270, 273 
 Testicle, 372 
 Thymus, 347 
 Thyroid. 345 
 Tracheal, 355 
 Tonsil, 314 
 Tyson's, 372 
 Urethral, 369, 370 
 of Vascular System, 348 
 
 Glands, Vestibulares, 378 
 Glans Clitoridis, 378 
 
 Penis, 372 
 
 Glaserian Fissure, 19, 43 
 Glenoid, 3 
 
 Glisson's Capsule, 3.36 
 Globus Major Epididymis, 273 
 
 Minor Epididymis, 273 
 Glomus Caroticum, 345 
 
 Coccygeum, 349 
 Glottis, 353 
 Golgi's Cells, 176, 208 
 Gomphosis, 59 
 Graafian Vesicles, 383 
 Granulationes Arachnoideales, 181, 182 
 Gray Matter (substantia grisea), 176 
 of Aquaeduct of Sylvius, 202 
 of Cerebellum, 208 
 of Cerebrum, 179 
 of Medulla Oblongata, 209 
 of Pons Varolii, 204 
 of Spinal Cord, 215 
 
 Nervous Tissue, 176 
 
 Rami Communicantes, 227, 238 
 Groove, Alar, 24 
 
 Auriculo- ventricular, 118 
 
 Bicipital, 47 
 
 Infraorbital, 27 
 
 Intertubercular, 47 
 
 Interventricular, 118 
 
 Lacrimal, 29 
 
 Musculo-spiral, 47 
 
 Mylo-hyoid, 35 
 
 Naso : palatine, 33 
 
 Nervi Radialis, 47 
 
 Occipital, 20 
 
 Optic, 22 
 
 Pterygo-palatine, 24, 28 
 Gubernaculum Testis, 375 
 Gudden's Commissure, 194, 292 
 Gullet, 322 
 Gums, 317 
 Gyrus, see Convolution or Lobe 
 
 HABENULAR Ganglion, 194 
 
 Trigone, 194 
 Haemal Glands, 172 
 
 Lymph Glands, 172 
 Hair Cells, Auditory, 310 
 Hairs, 273 
 
 Olfactory, 279 
 Hamstrings, 112 
 Hamular, 3 
 Hamulus, 306 
 Hand, 50, 105 
 Hasner's Valve, 296 
 Haversian Canals, 4 
 
 Spaces, 4 
 
 System, 4 
 
 Head-plates, Auditory, 310 
 Heart, 118 
 Heel, 57 
 
 Helicotrema, 306 
 Helix, 297 
 
 Hemispheres, Cerebral, 183 
 Henle's Loops, 362 
 Hensen's Canal, 307 
 
 Cells. 307 
 
412 
 
 INDEX 
 
 Hepar, 336 
 Hernia, 384 
 
 Femoral, 388 
 
 Coverings of, 390 
 
 Inguinal, 385 
 
 Coverings of, 388 
 Herophilus' Torcular, 18 
 Hesselbach's Triangle, 387 
 Key's Ligament, 390 
 Hiatus Canalis Facialis, 20 
 
 Falk>pii, 20, 42 
 
 Semilunaris, 277 
 
 Highmore (Nathaniel), Antrum of, 27 
 Hilton's Sac, 354 
 
 Hilum or Hilus of the Kidney, 360 
 of the Lung, 358 
 of the Spleen, 348 
 of the Supra-renal Gland, 364 
 Hind-brain, 203 
 Hip-joint, 68 
 Hippocampus Major i 191 
 
 Minor, 191 
 
 Horner's Muscle (tensor-tarsi), 75 
 Houston's Valves, 335 
 Huguier's Canal, 19, 300 
 Humerus, 47 
 Humor, Aqueous, 287 
 Hunter's Canal, no, 142 
 Hyal, Basi-, 41 
 
 Cerato-, 41 
 
 Stylo- (styloid process), 21 
 
 Thyro-, 41 
 
 Tympano- (vaginal process), 21 
 Hydatid's of Morgagni, 373, 382 
 Hyoid Pone, 41 
 Hymen, 378 
 Hypochondrium, 324 
 Hypogastrium, 324 
 Hypothalamus, 202 
 Hypothenar Eminence, 106 
 Hypophysis Cerebri, 186 
 
 ILEUM, 331 
 
 Iliac Regions, 324 
 
 Ilium, 13 
 
 Incisura Acetabuli, 12 
 
 Cerebelli, 206 
 
 Intertragica, 297 
 
 Marsupialis, 206 
 
 Radialis, 49 
 
 Rivini, 298 
 
 Semilunaris, 49 
 
 Thyroidea, 350 
 Incus, 301 
 
 Infundibula of the Kidney, 361 
 Infundibulum, 26, 277 
 
 Cerebri, 186 
 
 Cochleas, 306 
 
 Nasal, 277 
 
 Tubae, Uterinae, 382 
 Inguinal Regions, 324, 385 
 Insula Cerebri, 183 
 Inter-brain, 192 
 Interspaces, Perinatal, 393 
 Intestine, Large, 333 
 
 Small, 330 
 Intestinum Crassum, 333 
 
 Tenue, 330 
 
 Intumescentia Ganglioformis, 225 
 Iris, 284 
 
 Ischio-pubic Ramus, 12 
 Ischio-rectal Fossa, 394 
 
 Anterior Extension of, 394 
 
 Region, 394 
 
 Space 394 
 Ischmm, 13 
 Island of Reil, 183 
 Isthmus Cerebri, 194 
 
 of Fallopian Tube, 382 
 
 Faucium, 314 
 
 of Hind-brain, 203 
 
 Rhombenecephali, 178, 203 
 
 of Thyroid Gland, 345 
 
 Tubas Auditivae, 303 
 
 Uterinae, 382 
 
 Iter Chordae Anterius, 19, 300 
 Posterius, 300 
 
 a Tertio ad Quartum Ventriculum, 
 
 202 
 Ivory, 318 
 
 JACOB'S Membrane, 287 
 Jacobson's Nerve, 221, 250, 303 
 
 Organ, 278 
 Joint, see Articulations 
 
 Ankle, 71 
 
 Elbow, 66 
 
 Hip, 68 
 
 Rotators of the Hip- joint, 112 
 
 Knee, 69 
 
 Shoulder, 65 
 
 Wrist, 67 
 Joints, Motion in, 60 
 
 Structure of, 60 
 Jugular, Foramen, 42 
 
 Fossa, 1 8, 21 
 
 Ganglia, 226 
 
 Process, 18 
 
 Surface, 21 
 
 Vein, 165 
 
 KNEE-JOINT, 69 
 Kidney, 360 
 Kirkring's Valves, 332 
 Krause's End-bulbs, 177. 272 
 
 LABI A Oris, 312 
 
 Pudendi Majora, 377 
 
 Minora, 377 
 Labium Tympanicum, 309 
 
 Vestibulare, 309 
 Labyrinth, 304 
 
 Membranous, 304, 307 
 
 Osseous, 304, 305 
 Lacertus Fibrosus, 133 
 Lachrymal, see Lacrimal 
 Lacrimal Apparatus, 295 
 
 Bone, 29 
 
 Canaliculi, 295 
 
 Canals, 295 
 
 Carunci, 295 
 
 Fossa, 15, 36 
 
 Glands, 300 
 
 Groove, 24 
 
 Nerve, 218, 246 
 
 Papilla, 294 
 
INDEX 
 
 413 
 
 Lacrimal Punctum, 294 
 
 Sac, 296 
 
 Lacteals, 171, 332 
 Lacuna Magna Urethrae, 369 
 Lacunae, 4 
 
 Lacus Lacrimalis, 293 
 Lamina Basilaris, 309 
 
 Chorio-capillaris, 283 
 
 Cinerea, 186 
 
 Cribrosa Auris, 311 
 Scleraj, 281 
 
 Elastica, 282 
 
 Pusca, 281 
 
 Papyracea, 26 
 
 Reticularis, 310 
 
 Spiralis, 306 
 
 Superchoroidea, 283 
 
 Terminalis, 186 
 
 Vasculosa, 283 
 Laminae, 5 
 
 Lancisi's Nerves, 190 
 Larynx, 350 
 Layer, Basilar (skin), 270 
 
 Ganglionic (retinal), 286 
 
 Granular (cerebellar), 209 
 
 Molecular (cerebellar), 209 
 (retinal), 286 
 
 Nuclear (retinal), 286 
 
 Papillary (skin), 271 
 
 Pigmentary (retinal), 287 
 
 of Rods and Cones (retinal), 286 
 
 Rust-colored (cerebellar), 208 
 
 Turner's (cerebellar), 208 
 Leg, 54 
 Lemniscus, Lateral, 199 
 
 Medial, 198 
 Lens, Crystalline, 288 
 Lieberkuhn's Crypts, 332 
 Ligament, 60 
 Ligament or Ligaments 
 
 Acromio-clavicular, 65 
 
 Alar, 71 
 
 of Ankle-joint, 72 
 
 Annular, Anterior, 105 
 Posterior, 105 
 
 Anterior Common, 61 
 
 Arcuate, 107 
 
 Astragalo-navicular, 72 
 
 Atlanto-axial, 61 
 
 Atlo-axoid, 61 
 
 of the Bladder, 366 
 
 Broad of Liver, 338 
 of 'Uterus, 381 
 
 Burns', 390 
 
 Calcaneo-astragaloid, 72 
 
 Calcaneo-cuboid, 72 
 
 Calcaneo-navicular, 72 
 
 Capsular, see Individual Joints 
 
 Carpo-metacarpal, 68 
 
 of Carpus, 67 
 
 Check, 62, 80 
 
 Chondro-sternal, 63 
 
 Chondro-xyphoid, 63 
 
 Coccygeal, 63 
 
 Conoid, 65 
 
 Coraco-acromial, 65 
 
 Coraco-clavicular, 65 
 
 Coraco-humeral, 65 
 
 Ligaments, Coronal, 71 
 Coronary, 71, 327 
 Costo-clavicular, 65 
 Costo-central, 62 
 Costo-transverse, 63 
 Costo-yertebral, 62 
 Cotyloid, 69 
 Crico-arytenoid, 353 
 Crico-thyroid Capsular, 353 
 Crico-tracheal, 353 
 Crucial, 70 
 Cruciform, 62 
 Deltoid, 72 
 Dentate, 213 
 
 Dorsal, see Individual Joints 
 of Elbow- joint, 66 
 of Eye, 280 
 Falciform, 64, 339 
 of Fingers, 68 
 of Foot, 72 
 Gimbernat's. 387 
 Glenoid, 65 
 Glosso-epiglottic, 353 
 of Hand, 68 
 Key's, 390 
 of Hip-joint, 69 
 Hyo-epiglottic, 352 
 Ilio-femoral, 69 
 Ilio-lumbar, 63 
 Ilio-pectineal, 107 
 of Incus, 302 
 Inguinal, 387 
 Interarticular, 62 
 Interchondral, 63 
 Interclavicular, 65 
 Interosseous, see Individual Joints 
 Interspinous, 61 
 Intertransverse, 61 
 Intervertebral, 61 
 Ischio-fempral, 69 
 of Knee-joint, 69 
 of Larynx, 352 
 of Larynx, 352 
 
 Lateral, see Individual Joints 
 Lieno-renal, 348 
 of Liver, 338 
 Lockwood's, 76, 281 
 Lumbo-sacral, 63 
 of the Lung, 356 
 of Malleus, 302 
 Metacarpal, 68 
 Metacarpo-phalangeal, 68 
 Metatarsal, 73 
 Metatarso-phalangeal, 73 
 Nuchal. 6 1, 88 
 Occipito-atlantal, 62 
 Occipito-axial, 62 
 Occipito-odontoid, 62 
 of the Odontoid Process, 62 
 Orbicular of Radius, 66 
 of the Ossicles, 302 
 of the Ovary, 383 
 Palpebral, 294 
 Patellar, 69 
 Pectineo-femoral, 69 
 Peritoneal, 326, 327 
 Phreno-colic, 335 
 Plantar, 72 
 
4 i4 
 
 INDEX 
 
 Ligaments, Posterior Common, 61 
 Poupart's, 108, 387 
 Pterygo-mandibular, 78 
 Pubic, 64 
 
 Pubo-prostatic, 366 
 Pubo-vesical, 366 
 Radio-carpal, 67 
 Radio-ulnar, 67 
 Recto- vaginal, 381 
 Rhomboid, 65 
 Round of Hip- joint, 69 
 
 of Liver, 339 
 
 of Uterus, 381 
 Sacro-C9ccygeal, 64 
 Sacro-iliac, 64 
 Sacro-sciatic, 64 
 Sacro-spinous, 64 
 Sacro-tuberous, 64 
 Sacro-uterine, 381 
 of the Scapula, 65 
 of Shoulder, 65 
 Spiral of Cochlea, 309 
 or Spleen, 348 
 Spleno- phrenic, 348 
 Spheno-mandibular, 65 
 of Stapes, 302 
 Stellate, 62 
 Sterno-clavicular, 65 
 of the Sternum, 63 
 Stylo-hyoid, 21, 41 
 Stylo-mandibular, 61 
 Subpubic, 64 
 Supra-pubic, 64 
 Supra-spinous, 61 
 Suspensory of Bladder, 366 
 
 of Eye, 281 
 
 of Incus, 302 
 
 of Lens, 288, 289 
 
 of Liver, 339 
 
 of Odontoid, 62 
 
 of Ovary, 383 
 
 of Penis, 393 
 
 of Spleen, 348 
 Tarsal of Eye, 294 
 Temporo-mandibular, 60 
 Thyro-arytenoid, 353 
 Thyro-epiglottic, 353 
 Thyro-hyoid, 353 
 Tibio-fibular, 71 
 Transverse of Atlas, 61 
 
 Cotyloid, 69 
 
 of Knee, 71 
 
 of Scapula, 46 
 Trapezoid, 65 
 Triangular, 393 
 Ulno-carpal, 67 
 Utero-sacral, 381 
 Utero-vesical, 381 
 of the Uterus, 381 
 of Vertebrae, 61 
 of Winslow, 70 
 of Wrisberg, 71 
 Y-ligament, 69 
 of Zinn, 76 
 
 Ligamentum or Ligamenta 
 Alaria, 71 
 Arcuata, 107 
 Calcaneo-fibulare, 72 
 
 Ligamenta, Calcaneo-tibiale, 72 
 Carpi Dorsale, 105 
 
 Transversum, 105 
 Collaterale, Fibulare, 70 
 
 Radiale, 66 
 
 Tibiale, 70 
 
 Ulnare, 66 
 
 Coronaria Hepatis, 327, 339 
 Cruciata Cruris, 115 
 Denticulatum, 213 
 Falciforme Hepatis, 339 
 Gastro-lienale, 326 
 Hepato-gastricum, 326 
 Hyo-thyreoidea, 353 
 Inguinale, 387 
 
 Reflexum, 387 
 Laciniatum, 115 
 Lacunare, 387 
 Lata Uteri, 381 
 Latum Pulmonis, 356 
 Lieno-renale, 327 
 Mucosum, 71 
 Nuchae, 61, 88 
 Patellae, 69 
 
 Pectinatum Iridis, 285 
 Peronaei Retinaculum, 115 
 Sacro-spinosum, 64 
 Sacro-tuberosum, 64 
 Spirale Cochleae, 309 
 Suspensorium Dentis, 62 
 Talo-fibulare, 72 
 Teres Femoris, 69 
 
 Hepatis, 339 
 
 Umbilicale, 365 
 
 Uteri, 381 
 
 Thyreo-epiglotticum, 353 
 Transversum Cruris, 115 
 Triangulare Hepatis, 339 
 Light Spot, 298 
 Limbus Fossae Ovalis, 119 
 Laminae Spiralis, 309 
 Line, Inter-trochanteric, 53 
 
 Popliteal, ss 
 Linea Aspera, 53 
 
 Ilio-pectinea, 14 
 
 Quadrati (inter-trochanteric ridge), 
 
 Lines, Schreger's, 319 
 
 Lingua, 273 
 
 Lingula Cerebelli, 203 
 
 Lips, 312 
 
 Liquor Morgagni, 289 
 
 Lithotomy, Structures Concerned, 396 
 
 Littr6's Glands, 369 
 
 Liver, 336 
 
 Structure of, 339 
 Lobe of the Ear, 297 
 Lobes and Gyri of the Brain 
 
 Ala Lobuli Centralis, 207 
 
 Amygdala, 207 
 
 Angular, 185 
 
 Biventral, 207 
 
 Broca's, 185 
 
 Buccal, 188 
 
 Centralis, Anterior, 185 
 Posterior, 185 
 
 Clivus Monticuli, 207 
 
 Commissura Simplex, 207 
 
INDEX 
 
 415 
 
 Lobes, Cresenctic, 207 
 
 Culmen Monticuli, 207 
 
 Cuneus, 186 
 
 Dentate, 191 
 
 Diclive, 207 
 
 Flocculus, 207 
 
 Folium Cacuminis, 207 
 
 Fraenulum, 207 
 
 Frontal, 185 
 
 Fusiformis, 186 
 
 Glandular, 188 
 
 Gracile, 207 
 
 Hippocampal, 186 
 
 Limbic, 183 
 
 Lingualis, 186 
 
 Lingula, 207 
 
 Lobulus Centralis, 207 
 
 Occipital, 186 
 
 Occipito-temporal, 186 
 
 Olfactory, 183 
 
 Operti, 1 86 
 
 Orbital, 185 
 
 Parietal, 185 
 
 Postcentral, 186 
 
 Postparietal, 185 
 
 Precentral, 186 
 
 Precuneus, 185 
 
 Pyramid, 207 
 
 Semilunar, 207 
 
 Slender, 207 
 
 Subcalcarine, 186 
 
 Supramarginal, 185 
 
 Temporal, 183, 186 
 
 Tonsil, 207 
 
 Tuber Valvulae, 207 
 
 Uncinate, 186 
 
 Uvula, 207 
 
 Vermis, 206, 207 
 
 Vinculum Lingulae, 207 
 
 Worm, 206, 207 
 Lobes of the Cerebellum, 207 
 
 of the Cerebrum, 183 
 
 of the Liver, 338 
 
 of the Prostate Gland, 370 
 
 of the Thyroid Gland, 345 
 Lobule of the Ear, 297 
 Lobules of Liver, 340 
 
 of the Lung, 359 
 
 of the Mammary Gland, 384 
 Lobus Caudatus, 338 
 
 Quadratus, 338 
 
 Spigelii, 338 
 
 Lockwood's Ligament, 76 
 Locus Caeruleus. 20 a, 212 
 
 Perforatus, 186 
 Loops of Henle, 362 
 Lower's Tubercle, 120 
 Lumbar Regions, 324 
 Lumbo-dorsal Fascia, 90 
 Lungs, 357 
 Lunula, 273 
 Lymphatic System, 171 
 
 Vessels, 171 
 Lymph Glands, 171 
 Haemal, 172 
 
 Space, Peri-choroidal, 283 
 Peri-sclerotic, 281 
 
 Spaces of Eye, 290 
 
 Lymphatics of the 
 
 Abdomen, 174 
 
 Auricular Region, 173 
 
 Bladder, 368 
 
 Bronchi, 175, 356 
 
 Buccal Region, 173 
 
 Cardiac Region, 175 
 
 Cervical Region, 173 
 
 Head, 172 
 
 Inguinal Region, 174 
 
 Intestine, 333, 336 
 
 Larynx, 354 
 
 Liver, 341 
 
 Lower Extremity, 174 
 
 Lung, 359 
 
 Kidney, 363 
 
 Mammary Gland, 384 
 
 Mastoid Region, 173 
 
 Mediastinum, 175 
 
 Mesentery, 175 
 
 Neck, 172, 173 
 
 Pancreas, 344 
 
 Parotid Regi9n, 173 
 
 Pectoral Region, 174 
 
 Pelvis, 174 
 
 Occipital Region, 172 
 
 Spleen, 349 
 
 Submandibular Region, 173 
 
 Supra-renal Gland, 365 
 
 Testicle, 375 
 
 Thymus Gland, 347 
 
 Thyroid Gland, 346 
 
 Tongue, 275 
 
 Trachea, 356 
 
 Upper Extremity, 173 
 
 Uterus, 382 
 
 Vagina, 379 
 Lympho-glandulae, 171 
 
 Auriculares, 173 
 
 Bronchiales, 175, 356 
 
 Ceryicales, 173 
 
 Cubitales, 173 
 
 Linguales, 173 
 
 Mesentericae, 175 
 
 Occipitales, 172 
 
 Parotidae, 173 
 
 Submaxillares, 173 
 Lyra, 190 
 
 MACULA Acustica, 307 
 
 Lutea, 285 
 
 Saccularis, 308 
 
 Utricularis, 308 
 Malar Bone, 30 
 Malleolus, 55. 56 
 Malleus, 301 
 Malpighi's Bodies, 349, 361 
 
 Pyramids, 361 
 Malpighian Tufts, 361 
 Mammary Gland, 383 
 Mandible, 33 
 Manubrium of Malleus, 301 
 
 of Sternum, 8 
 Marrow of Bones, 4 
 Massa Intermedia, 193 
 Masses, Lateral of Ethmoid, 26 
 Mastoid, 3 
 
 Cells, 20 
 
4 i6 
 
 INDEX 
 
 Mastoid, Foramen, 20 
 
 Process, 20 
 Matrix of Nail, 273 
 Maxilla, 27 
 
 Meatus Acusticus Externus, 297 
 Interims, 311 
 
 Auditorius Externus, 20, 297 
 Internus, 20, 42, 311 
 
 Nasi, 3.8, 277 
 
 Urinarius, 369, 370 
 Meckel's Diverticulum, 331 
 
 Ganglion, 224 
 
 Media, Refracting of Eye, 287 
 Mediastinum Testis, 374 
 
 Thoracis, 356 
 Medulla Oblongata, 208 
 
 Spinalis, 213 
 Membrana Basilaris, 309 
 
 Crico-thyroidea, 353 
 
 Granulosa, 383 
 
 Limitans Externa, 287 
 Interna, 286 
 
 Nictitans, 295 
 
 Pupillaris, 285 
 
 Sacciformis, 67 
 
 Tectoria, 309 
 
 Tympani, 298 
 
 Secundaria, 300 
 Membrane or Membranes 
 
 Brain, 180 
 
 Bruch's, 283 
 
 Demour's, 282 
 
 Descemet's, 282 
 
 Hyaloid, 288 
 
 Hyo-glossal, 274 
 
 Hyo-thyroid, 353 
 
 Interosseous, 67, 71 
 
 Jacob's, 287 
 
 Limiting, 286, 287 . 
 
 Meningeal, 180, 213 
 
 Mucous, 271 
 
 Nasmyth's, 319 
 
 Obturator, 12 
 
 Pituitary, 278 
 
 Reissner's, 309 
 
 Schneiderian, 278 
 
 Shrapnell's, 298 
 
 of Spinal Cord, 213 
 
 Synovial, 60 
 Carpal, 67 
 Tarsal, 72 
 
 Thyro-hyoid, 353 
 
 Thyroid, 12 
 
 Vestibular, 309 
 Meninges of Brain, 180 
 
 of Spinal Cord, 213 
 Menisci of Knee-joint, 70 
 Mesenteries, 327 
 Mesencephalon, 178, 203 
 Mesencephalic Root of Fifth Nerve, 
 Meso-colon, 327, 334 
 Meso-rectum, 327 
 Meso-sigmoid, 327 
 Metacarpus, 51 
 Metapore, 182, 211 
 Metatarsus, 58 
 Metathalamus, 193 
 Metencephalon, 178, 203 
 
 Meynert's Commissure, 292 
 Mid-brain, 178, 194 
 Modiolus Cochleae, 306 
 Moll's Glands, 293 
 Mons Veneris, 377 
 Morgagni's Hydatids, 373, 382 
 Lacuna, 360 
 Sinus, 359 
 Mouth, 312 
 Miiller's Fibres, 286 
 Munro's Foramen, 190 
 Muscle or Muscles, 73 
 Abdominal, 95 
 Abductor Digiti Quinti (hand), 106 
 
 .(foot), 116 
 Indicis (ist dorsal interosseous), 
 
 107 
 Minimi Digiti (foot), 116 
 
 Digiti (hand), 106 
 Pollicis, 106 
 Brevis, 106 
 Longus, 105 
 Accelerator Urinae, 98 
 Accessories ad Ilio-costalem, 91 
 of Acromial Region, 100 
 Adductor Brevis (femoris), no 
 Longus (femoris), no 
 Magnus (femoris), no 
 Obliquus Hallucis, 117 
 
 Ppllicis, 106 
 Pollicis, 106 
 Transyersus Hallucis, 117 
 
 Pollicis, 106 
 Ancpneus, 104 
 Anti-tragicus, 80, 297 
 Appendicular, 86, 87 
 of Arm, 100 
 Articularis Genu, 109 
 Aryteno-epiglottideus Inferior, 86 
 
 Superior, 86 
 Arytenoideus, 86 
 Attollens Auriculam, 75 
 Attrahens Auriculam, 75 
 of Auricle, 297 
 Auricularis Anterior, 75 
 Posterior, 75 
 Superior, 75 
 
 Axial. 87 
 
 ygos UT 
 of Back, 86 
 
 Azygos Uvulae, 84 
 
 Biceps, ip i 
 
 Femoris, 112 
 
 Flexor Cubiti, 101 
 Biventer Cervicis, 92 
 of the Bladder, 367 
 Bowman's (ciliary), 284 
 
 (Cochlear), 309 
 Brachialis, 101 
 
 Anticus, loi 
 Brachio-radialis, 104 
 of Buccal Region, 78 
 Buccinator, 78 
 Bulbocavernosus, 98 
 Caninus, 77 
 
 of Cervical Region, 80, 84 
 Cervicalis Ascendens, 91 
 Chondro-glossus, 81 
 Ciliary, 284 
 
INDEX 
 
 417 
 
 Muscles, Circumflexus (tensor) Palati, 83 
 Coccygeus, 98 
 Complexus, 92 
 
 Compressor Narium Minor, 77 
 Nasi, 77 
 Sacculi Laryngis of Hilton (ary- 
 
 teno-epiglottideus inf.), 86 
 Urethrae (female), 99 
 
 (male), 98 
 Constrictor Isthmi Paucium, 84 
 
 Pharyngis In 
 Middle, 83 
 
 is Inferior, 83 
 
 Superior, 83 
 Coraco-brachialis, 101 
 of Cranial Region, 75 
 Corrugator Cutis Ani, 97 
 
 Supercilii, 75 
 Cremaster, 95 
 Crico-arytenoid, Lateral, 86 
 
 Posterior, 85 
 
 Crico-thyroid (thyreoideus), 85 
 Crureus, 109 
 
 Cursor Ani (latissimus dorsi), 88 
 Deltoid (deltpideus), 100 
 Depressor Ali Nasi, 77 
 
 Anguli Oris, 78 
 
 Labii Inferioris, 78 
 
 Septi Nasi, 77 
 Detrusor Urinse (outer muscular 
 
 coat of the bladder), 367 
 Diaphragm, 94 
 Digastric, 82 
 
 Dilator Naris Anterior, 77 
 Posterior, 77 
 
 Pupillae, 285 
 
 Tubae Auditivae, 303 
 of Dorsal Region, 86 
 of the Ear, 75. 79, 297 
 Ejaculator Seminis (bulbo-caverno- 
 sus), 98 
 
 U rinse (bulbo-cavernosus), 98 
 of the Epiglottis, 85, 354 
 Erector Clitoridis (ischio-caverno- 
 sus), 09 
 
 Penis (ischio-cavernosus), 99 
 
 SpinEB, 90 
 
 of the Eustachian Tube, 303 
 of Expression, 77, 79 
 Extensor Brevis Digitorum, 115 
 Pollicis, 1 05 
 
 Carpi Radialis Brevoir, 104 
 
 Longior, 104 
 Ulnaris, 104 
 
 Coccygis, 93 
 
 Communis Digitorum, 104 
 
 Digiti Quinti Proprius, 104 
 
 Hallucis Longus, 113 
 
 Indicis, 105 
 
 Longus Digitorum, 113 
 Hallucis, 113 
 Pollicis, ip$ 
 
 Minimi Digiti, 104 
 
 Ossis Metacarpi Pollicis, 105 
 Extensor, Primi Internodii Pollicis, 
 105 
 
 Proprius Hallucis, 113 
 
 Secundi Internodii Pollicis, 105 
 External Oblioue (abdomen), 95 
 
 Muscles of Eyeball, 76, 289 
 of Eyelid, 75, 294 
 of the Face, 77, 79 
 of the Femoral Region, 108, no, 112 
 of the Fibular Region, 115 
 Flexor Accessorius, 116 
 Brevis Digitorum, 116 
 Hallucis, 117 
 Minimi Digiti (foot), 117 
 
 (hand), 106 
 Pollicis, 106 
 Carpi Radialis, 102 
 
 Ulnaris, 103 
 Digiti Quinti Brevis (foot), 117 
 
 (hand), 106 
 Digitorum Brevis, 106 
 Hallucis Brevis, 117 
 Longus Digitorum, 114 
 Hallucis, 114 
 Pollicis, 103 
 Ossis Metacarpi Pollicis (oppo- 
 
 nens), 106 
 Pollicis Brevis, 106 
 
 Longus, 103 
 
 Profundus Digitorum, 103 
 Sublimis Digitorum, 103 
 of the Forearm, 102 
 of the Foot, 115 
 Frontalis, 75 
 Gastrocnemius, 113 
 Gamellus Inferior, in 
 
 Superior, in 
 Genio-glossus, 82 
 Genio-hyo-glossus, 82 
 Genio-hyoid, 82 
 Glosso-palatinus, 84 
 of the Gluteal Region, no 
 Glutaeus or Gluteus Maximus, no 
 Medius, no 
 Minimus, ill 
 Gracilis, 109 
 Hamstring, 112 
 of the Hand, 106 
 of the Head, 75 
 Helicis Major, 79, 297 
 
 Minor, 80, 297 
 
 Hilton's (aryteno-epiglottideus in- 
 ferior), 86 
 of the Hip, 1 10 
 Hip Rotators, 112 
 Homer's (tensor tarsi), 75 
 of Humeral Region, 101 
 Hyo-glossus, 82 
 Hyppthenar, 106 
 of Iliac Region, 107, no 
 Iliacus, 108 
 Ilio-capsularis (outer fibres of 
 
 iliacus), 108 
 Ilio-coccygeus (posterior fibres of 
 
 levator ani), 98 
 Ilio-costales, 91 
 
 Lumborum, 91 
 Infra-cost ales, 94 
 Infra-hyoid Region, 81 
 Infraspinatus, 101 
 Intercostal, External, 93 
 
 Internal, 93 
 Internal Oblique (abdomen), 95 
 
4*8 
 
 INDEX 
 
 Muscles, Interossei of foot, 117 
 Inter-spinales, 93 
 Inter-transversaTes, 92 
 Iritertransversarii, 93 
 Involuntary, 74 
 Ischio-cavernosus, 98, 99 
 of Ischio-rectal Region, 97, 395 
 Kerato-cricoideus, 85 
 Labial Region, 77 
 of Larynx, 85, 354 
 Latissimus Dorsi, 88 
 Laxator Tympani, 80 
 of the Leg, 112 
 Levator Anguli Oris, 78 
 Scapulae, 88 
 
 Ani, 98 
 
 Glandulae Thyroideae, 346 
 
 Labii Superioris, 77 
 Alasque Nasi, 77 
 
 Menti, 78 
 
 Palati, 83 
 
 Palpebrae Superioris, 76 
 
 Prostatae (pre-anal fibres of 
 levator am), 98 
 
 Scapulae, 88 
 
 Urethrae (pre-anal fibres of 
 levator ani), 98 
 
 Veli Palatini, 83 
 Levatores Costarum, 94 
 Lingualis, 83 
 Lingual, Longitudinal, 83 
 
 Transverse, 83 
 
 Vertical, 83 
 of Lingual Region, 82 
 Longitudinalis Linguae Inferior, 83 
 
 Superior, 83 
 Longissimus Capitis, 91 
 
 Cervicis, 91 
 
 Dorsi, 91 
 Longus Capitis, 84 
 
 Colli, 84 
 
 of Lower Extremity, 107 
 Lumbricales of foot, 116 
 
 of hand, 107 
 Mandibular Region, 78 
 Masseter, 79 
 of Mastication, 79 
 of Maxillary Region, 77 
 Mentalis, 78 
 Multifidus, 92 
 
 Spinae, 92 
 Mylo-hyoid, 82 
 Nasalis, 77 
 of Nasal Region, 77 
 Naso-labialis (upper medial fibres 
 
 of orbiculans oris), 78 
 of Neck, 80 
 
 Obliquus Abdominis Externus, 95 
 Internus, 95 
 
 Auriculae, 80, 297 
 
 Capitis Inferior, 93 
 Superior, 93 
 
 Oculi Inferior, 77 
 Obliquus Oculi, Superior, 76 
 Obturator Externus, 112 
 
 Internus, 112 
 Occipitals, 75 
 Occipito-frontalis, 75 
 
 Muscles, Omo-hyoid, 81 
 
 Opponens Digiti Quinti, 107 
 
 Minimi Digiti, 107 
 
 Ppllicis, 106 
 Orbicularis Oculi, 75 
 
 Oris, 78 
 
 Palpebrarum, 75 
 of Orbital Region, 76, 289 
 of Palatal Region, 83, 313 
 Palato-glossus, 8j 
 Palato-pharyngeus, 84 
 of Palmar Region, 106 
 Palmaris Brevis, 106 
 
 Longus, 102 
 of Palpebral Region, 75 
 Fectineus, no 
 of Pectoral Region, 99 
 Pectoralis Major, 99 
 
 Minor, 99 
 
 of Pelvic Outlet, 97 
 Perforans, 103 
 Perforatus, 103 
 of Perinaeum, female, 99, 396 
 
 Male, 98, 393 
 of Peroneal Region, 115 
 Peroneus (peronasus) Brevis, 115 
 
 Longus, 115 
 
 Tertius, 113 
 
 of Pharyngeal Region, 83, 322 
 Pharyngo-glossus (superior con- 
 strictor), 83 
 Pharyngo-palatinus, 84 
 of Pinna, 79 
 of Plantar Region, 116 
 Plantaris, 114 
 Platysma-myoides, 80 
 Popliteus, 114 
 
 Prevertebral of Head and Neck, 84 
 Procerus, 77 
 Pronator Quadratus, 103 
 
 Radii Teres, 102 
 
 Teres, 102 
 Psoas Magnus, 107 
 
 Major, 107 
 
 Minor, 108 
 
 Parvus, 108 
 
 of Pterygo-mandibular Region, 79 
 Pterygoid, External, 79 
 
 Internal, 79 
 Pubo-coccygeus (medial fibres of 
 
 levator ani), 98 
 Pyrarnidalis, 97 
 
 Nasi, 77 
 Pyraformis, in 
 Quadratus FenKms, 112 
 
 Labii Inferioris, 78 
 Superioris, 78 
 
 Lumborum, 97 
 
 Menti, 78 
 
 Plantae, 116 
 Quadriceps Extensor, 108 
 
 Femons, 108 
 Radial Region, 102 
 Recti Oculi, 76 
 Recto-urethralis (pre-anal fibres 
 
 of levator ani), 98 
 Recto-uterinus (sacro-uterine liga- 
 ment), 381 
 
INDEX 
 
 419 
 
 Muscles, Rectus Abdominis, 96 
 
 Capitis Anticus Major, 84 
 
 Minor, 84 
 Lateralis, 84, 93 
 Posticus Major, 93 
 Minor, 93 
 
 Femoris, 109 
 
 Oculi Externus, 76 
 Inferioris, 76 
 Internus, 76 
 Lateralis, 76 
 Medialis, 76 
 Superioris, 76 
 Retrahens Auriculam, 75 
 Rhomboideus Major, 89 
 
 Minor, 88 
 Risorius, 79 
 Rotatores, 92 
 
 Spinse, 92 
 
 Rotators of the Hip, no 
 Sacro-lumbalis, 91 
 Sacro-spinalis, 90 
 Salpingo-pharyngeus, 84 
 Santorini's (risorius), 79 
 Sartorius, 108 
 Scalenus Anticus (anterior), 85 
 
 Medius, 85 
 
 Posticus (posterior), 85 
 of the Scalp, 75 
 of Scapular Region, 100 
 Semi-membranosus, 112 
 Semi-spinalis Capitis, 92 
 
 Cervicis, 92 
 
 Colli, 92 
 
 Dorsi, 92 
 Serratus, Anterior, 100 
 
 Magnus, 100 
 
 Posticus (posterior) Inferior, 90 
 
 Superior, 89 
 of the Shoulder, 100 
 Skeletal (voluntary), 73, 74 
 Sphincter Ani Externus, 97 
 Internus, 97 
 Tertius, 97 
 
 Pupillae, 285 
 
 Vaginae, 99 
 
 Vesicae, 367 
 Spinalis Cervicis, 92 
 
 Colli, 92 
 
 Dorsi, 92 
 Splenius Capitis, 90 
 
 Cervicis, 90 
 
 Colli, 90 
 
 Stapedius, 80, 302 
 Striated Muscle, 73, 74 
 Striped Muscle, 73, 74 
 Structure of Muscle, 73 
 Stylo-glossus, 82 
 Stylo-hyoid, 82 
 Stylo-pharyngeus 83 
 Sub-anconeuc, 102 
 Subclavius, 100 
 Subcrureus, 109 
 of Suboccipital Region, 93 
 Subscapularis, 100 
 Supinator, 105 
 
 Brevis, 105 
 
 Longus, 104 
 
 Muscles of Supra-hyoid Region, 82 
 Supraspinatus, 101 
 Temporal, 79 
 
 of Temporo-mandibular Region, 79 
 Tensor Fasciae Femoris, 108 
 Latae, 108 
 
 Palati, 83 
 
 Tarsi, 75 
 
 Tympani, 80, 302 
 
 Vaginae Femoris, io3 
 
 Veli Palatini, 83 
 Teres Major, 101 
 
 Minor, 101 
 Thenar, 106 
 of Thigh, 108 
 of Thorax, 93, 99 
 Thyro-(thyreo) Arytenoideus, 86 
 Thyro-(thyreo) Epiglottideus, 86 
 Thyro-(thyreo) Hyoid, 81 
 Tibialis Anticus (anterior), 112 
 
 Posticus (posterior), 114 
 of Tibio-fibular Region, 112 
 Todd's (cochlear), 309 
 of the Tongue, Extrinsic, 82, 274 
 
 Intrinsic, 83, 275 
 Trachelo-Mastoid, 91 
 Tragicus, 80, 297 
 Transversalis Abdominis, 96 
 
 Cervicis, 91 
 
 Colli, 91 
 Transversus Auriculae, 80, 297 
 
 Linguae, 83 
 
 Pennaei Profundus, 98, 99 
 
 Superficialis, 98, 99 
 Trapezitts, 88 
 Triangularis Menti, 78 
 
 Sterni, 94 
 Triceps, 102 
 
 Extensor Cubitis, 102 
 Triticeo-glossus, 86 
 of the Trunk, 86 
 Turner's (Kerato-cricoideus), 85 
 of Tympanum, 80, 302 
 of Ulnar Region, 102 
 Unstriated Muscle, 73, 74 
 Unstriped Muscle, 73. 74 
 of Upper Extremity, 99 
 Urethral, 369 
 Uvulae, 84 
 Vastus Externus, 109 
 
 Intermedius, 109 
 
 Internus, 109 
 
 Lateralis, 109 
 
 Medialis, 109 
 Vertical is Linguae, 83 
 Voluntary Muscle, 73, 74 
 Zypomaticus, 78 
 
 Major, 78 
 
 Minor, 78 
 Muscular Fibre, 73 
 Musculi Papillares, 120, 122 
 Myencephalon, 177. 208 
 Myelology, 
 
 NAILS, 272 
 Nares, 276 
 Nasal Bones, 27 
 
 Conchae, 26, 32 
 
 Fossa, 277 
 
420 
 
 INDEX 
 
 Nasal Meatus, 26, 277 
 
 Septum, 276 
 
 Nasmyth's Membrane, 319 
 Naso-labial Band, 78 
 Nasopharynx, 321 
 Nates, 202 
 Navel, 298 
 Navicular Bone, 57 
 Neck of the Bladder, 366 
 
 of the Femur, 52 
 
 of the Humerus, 47 
 
 Surgical Triangles of, 128 
 
 of the Uterus, 398 
 Nerve or Nerves 
 
 Abducent, 219, 252 
 
 Accessorius, 222, 250 
 
 Acustic, 220, 310 
 
 Alveolar, 219, 246 
 
 Anastomoticus Tibialis, 235, 236 
 
 of Ankle-joint, 235 
 
 of the Arm, 229 
 
 Arnold's, 221, 250 
 
 Auditory, 220, 310 
 
 of Auditory Canal, 219, 246 
 
 of Auricle, 298 
 
 Auricular, Anterior, 219, 246 
 Great, 227, 254 
 from Pneumogastric, 221, 250 
 Posterior, 220, 248 
 
 Auricularis Magnus, 227 
 
 Axillaris, 229 
 
 Bell's, 229 
 
 of Bladder, 368 
 
 of Bronchi, 356 
 
 Buccal, of Facial, 220, 248 
 
 Long, 219 
 
 of ME 
 
 [andibular, 219, 246 
 Buccinator, 219, 246 
 Calcaneal, Lateral, 235, 267 
 
 Medial, 235, 267 
 Calcaneo-plantar, 235, 267 
 Canalis Pterygoidei, 226 
 Cardiac, 119 
 
 Cervical, 222, 237, 250, 268 
 
 Inferipr, 222 
 
 Superior, 222, 237, 268 
 
 Thoracic, 222, 250 
 Carotico-tympanic, 237 
 Carotid, 221 
 Cavernus, 242 
 Cells, 176 
 Cerebral, 216 
 Cervical, 220, 227 
 Cervico-facial, 220, 248 
 Chorda Tympani, 220, 248, 276 
 Ciliary, Long, 218, 246 
 
 Short, 224 
 Circumflex, 229, 260 
 Clunium Inferioris Medialis, 234 
 Coccygeal, 233, 262 
 Cochlear, 221, 252, 311 
 Communicantes, Gray Rami, 227 
 
 Fibular, 236 
 
 Hypoglossi, 228, 254 * 
 
 Peronei, 236, 267 
 
 Tibial, 235, 267 
 
 'White Rami, 227, 238 
 Cranial, 216 
 
 Nerves, Crural, Anterior, 233, 264 
 
 Genito-, 232, 264 
 Cutaneous, Abdominal, 231 
 Antibrachii Medialis, 229 
 
 Posterior, 229 
 Brachii Medialis, 229 
 
 Posterior, 230 
 C9lli, 227 
 Digitales Plantares, 235 
 
 Volares, 229 
 Dorsal, 230 
 
 Antibrachial, 229 
 Femoral, 234 
 
 External Femoral, 232, 264 
 Internal, 229, 256 
 
 Femoral, 233 
 Lateral Brachial, 229 
 
 Femoral, 232 
 Lesser Internal. 229, 256 
 Medial Antibrachial, 229 
 Brachial, 229 
 Femoral, 233, 264 
 Palmar, 229 
 Perforating 234, 266 
 Plantar, Lateral, 235 
 
 Medial, 236 
 Posterior Antibrachial, 229 
 
 Femoral, 234 
 Surae Lateralis, 236 
 
 Medialis, 235 
 
 Dental, Anterior Superior, 219, 246 
 Inferior, 219, 246 
 Middle Superior, 219, 246 
 Posterior Superior, 219, 246 
 Descendens Hypoglossi, 222, 252 
 Digastric of Facial, 220, 248 
 
 of Mylo-hyoid, 219, 246 
 Digital (foot), 235 
 
 (hand), 229 
 Digitales Plantares, 235 
 
 Volares, 229 
 Dorsal of Clitoris, 234, 266 
 
 of Penis, 234, 266 
 
 of the Ear, see Individual Portions 
 Eighth Cranial, 220, 252, 311 
 of Elbow-joint, 230 
 Eleventh Cranial, 222, 250 
 of Equilibration (vestibular), 221, 
 
 252, 319 
 Endings, 177 
 of Eustachian Tube, 304 
 of Eyeball, 218, 219, 289 
 of Eyelids, 218, 219, 289 
 Eye-muscles, 218, 219, 289 
 Facial, 220, 248 
 Femoral, 233 
 Fibres, 177 
 
 Fifth Cranial, 218, 2^6 
 First Cranial, 216, 244 
 Fourth Cranial, 217, 244 
 Frontal, 218, 246 
 Gastric, 222 
 Genital, 232, 264 
 Genito-crural, 232, 264 
 Genito-femoral, 232, 264 
 Glosso-palatine, 220, 248, 310 
 Glosso-pharyngeal, 221, 250 
 Gluteal, Inferior, 234, 266 
 
INDEX 
 
 421 
 
 Nerves, Gluteal, Superior, 234, 266 
 Gustatory, 219, 246 
 Haemorrhoidal, 234, 266 
 of Heart, 119 
 Hepatic, 340 
 of Hip-joint, 234 
 Hypo-glossal, 222, 252 
 Ilio-hypqgastric, 232, 264 
 Ilio-inguinal, 232, 264 
 Incisive, 219, 246 
 Infra-orbital, 218, 220, 246 
 Infra-trochlear, 218, 246 
 Intercostal, Abdominal, 231, 261 
 
 Thoracic, 231, 261 
 Intercosto-brachial, 231 
 Intercosto-humeral, 231 
 Intermedius (glosso-palatine), 220, 
 
 248, 310 
 Interosseous. Anterior from Median, 
 
 229, 258 
 
 from Anterior Tibial, 236 
 Antibrachii Dorsalis, 230 
 
 Volaris, 229 
 Posterior from Musculo-spiral, 
 
 230, 258 
 
 of the Intestines, 333, 336 
 of the Iris, 28$ 
 Ischiadicus, 234 
 Jacobson's, 221, 250, 303 
 of the Kidney, 363 
 of the Knee-joint, 235 
 Labial, 219, 246 
 Lacrimal, 218, 246 
 Lancisi's, 190 
 Laryngeal, External, 221, 250 
 
 Inferior, 222, 250 
 
 Internal, 221, 250 
 
 Recurrent, 222, 250 
 
 Superior, 221, 250 
 of the Larynx, 354 
 Lingual from Mandibular, 219, 246, 
 
 from Glosso-pharyngeal, 221, 250 
 of the Liver, 340 
 Lumbar, 232, 262 
 Malar, 219, 220 
 of the Mammary Gland, 384 
 Mandibular, 219, 246 
 Masseteric, 219, 246 
 Masticator, 201, 219, 246 
 Mastoid, 227 
 Maxillary, 218, 246 
 Median, 229, 258 
 of Membrana Tympani, 299 
 Meningeal, from sth, 219, 246 
 
 from loth, 221, 250 
 
 from I2th, 222, 250 
 
 of the Cord, 227 
 
 Recurrent, 227 
 Mental, 219 
 Motor-oculi, 217, 244 
 Musculo-cutaneous of Arm, 229, 
 258 
 
 of leg, 236, 267 
 Musculo-spiral, 230, 255 
 Mylo-hyoid, 219, 246 
 Nasal, 218, 219, 246 
 
 Posterior Inferior, 224 
 Superior. 224 
 
 Nerves, Nasal, Superior, 224 
 Naso-ciliary, 218 
 Naso-palatine, 224 
 Ninth Cranial, 221, 250 
 of the Nose, 279 
 Obturator, 232, 244, 264 
 
 Accessory, 232, 264 
 Occipital, Great, 227, 254 
 
 Small, 227, 254 
 Occipitalis Magnus, 227 
 
 Minimus, 227 
 Oculo-motor, 217, 244 
 Oesophageal, 222, 250 
 Olfactory, 216, 244 
 Ophthalmic, 218, 246 
 Optic, 217, 244, 291 
 Orbital, 219, 224, 246 
 of Orientation (vestibular) , 221, 
 
 252, 311 
 
 of the Ovary, 383 
 Palatine, Anterior, 224 
 
 External, 224 
 
 Large, 224 
 
 Medial, 224 
 
 Middle, 224 
 
 Posterior, 224 
 
 Small, 224 
 
 Palmar, 229, 230, 258, 260 
 Palpebral, 219, 246 
 of the Parotid, 219, 246 
 Pars Intermedia (glosso-palatine), 
 
 220, 248, 310 
 
 Patheticus, 217 
 
 Path, Optic-acustic Reflex, 199, 
 
 200 
 
 of the Penis, 372 
 Peronaeus Profundus, 236 
 
 Superficials, 236 
 Petrosal, Deep, 237 
 
 Great Superficial, 225 
 
 Small Superficial, 225 
 Pharyngeal, 224 
 
 from Ninth Cranial, 221, 250 
 
 from Tenth Cranial, 221, 250 
 Phrenic, 228, 254 
 Plantar, 235, 267 
 Plexuses, see Plexus 
 Pneumogastric, 221, 250 
 Popliteal, External, 235, 267 
 
 Internal, 235, 267 
 Portio Dura, 220 
 
 Mollis, 220 
 
 of the Prostate Gland, 371 
 Pterygoid, External, 219, 246 
 
 Internal, 219. 246 
 Pterygo-palatine, 224 
 Pudenda! Inferior, 234 
 
 Long, 234 
 Pudendus, 234 
 Pudic, 234, 266 
 Pulmonary, 222, 250 
 Radial, 230, 256 
 Radialis, 230, 256 
 Rami Communicantes, Gray, 227, 
 
 238 
 
 White, 227. 238 
 Respiratory, of Bell, 229 
 
 External, 229 
 
422 
 
 INDEX 
 
 Nerves, Respiratory, Internal, 228 
 Sacral, 233, 262 
 Saphenous, External, 235, 267 
 
 Internal, 233, 264 
 
 Long, 233, 264 
 
 Short, 235, 266 
 Sciatic, Great, 234, 266 
 
 Small, 234, 266 
 Scrotal, 232 
 
 Second Cranial, 217, 244, 291 
 Seventh Cranial, 220, 248 
 of Shoulder-joint, 65 
 Sixth Cranial, 219, 252 
 of the Spermatic Cord, 377 
 Spheno-palatine, 219, 246 
 Spinal, 216, 226, 254 
 
 Accessory, 222, 250 
 Splanchnic, Great, 227, 238, 268 
 
 Small, 227 
 
 of the Spleen, 241, 349 
 of the Stomach, 330 
 Stylo-hyoid, 220, 248 
 Stylo-pharyngeal, 221, 250 
 Suboccipital, 227, 254 
 Subscapular, 229, 260 
 Superficialis Colli, 227, 254 
 Supra-aero mial, 228 
 Supra-clavicular, 228 
 Supra-orbital, 218, 2^6 
 of the Supra-renal Gland, 365 
 Suprascapular, 229 
 Suprasternal, 228 
 Supratrochlear, 218, 246 
 Sural, 235, 236 
 Sympathetic, 236, 268 
 of Taste, 275, 276 
 Temporal, Deep, 219, 246 
 
 Superficial, 220, 248 
 
 Superior, 219, 246 
 Temporo-facial, 220, 248 
 Temporo-malar, 219 
 Tensoris Tympani, 225 
 
 Veli Palatim, 225 
 Tenth Cranial, 221, 250 
 Terminations of, 177 
 of Testicle, 375 
 Third Cranial, 217, 244 
 Thoracic, 231 
 
 Anterior, 229, 258, 260 
 
 Intercostals, 261 
 
 Long, 229, 256 
 
 Posterior, 229, 256 
 Thoraco-dorsalis, 229 
 of Thymus Gland, 347 
 Thyro-hyoid, 222, 252 
 of Thyroid Gland, 346 
 Tibial, Anterior, 236, 267 
 
 Posterior, 235, 267 
 Tibialis, 235 
 of the Tongue, 275, 276 
 Tonsillar, 221, 250, 315 
 of Trachea, 356 
 Trifacial, 218, 246 
 Trigeminal, 218, 246 
 Trochlear, 217, 244 
 Trancus Lumbo-sacralis, 233 
 Twelfth Cranial, 222, 252 
 Tympanic, 220, 248, 303 
 
 Nerves of Tympanic Membrane, 299 
 
 of Tympanum, 303 
 
 Ulnar, 229, 256, 260 
 
 of the Ureters, 364 
 
 of the Uterus, 382 
 
 of the Vagina, 380 
 
 Vagus, 221, 250 
 
 Vaso-motor, 122 
 
 Vedian, 226 
 
 of the Vesiculse Seminales, 377 
 
 of the Vulva, 379 
 
 Wrisberg's, 229 
 
 of Wrist-joint, 230 
 
 Zygomatic, 219 
 
 Zygomatico-facial, 219 
 
 Zygomatico-temporal, 219 
 Nervous System, 175, 242 
 
 Tables and Plates, 242 
 Neurilemma, 177 
 Neuroglia, 176, 214 
 Neurology, i 
 Neurones, 176 
 
 Nipple, 384 
 Nodule, 
 
 207 
 
 Noduli Lymphatici Agregati, 333 
 Lienalis, 349 
 
 Valvarum Semilunarum, 120 
 Nose, 276 
 
 Vestibule of, 176 
 Notch, Cerebellar, 206 
 
 Cotyloid, 12 
 
 Ethmoidal, 16 
 
 Frontal, 15 
 
 Great Sciatic, 13 
 
 Interclavicular, 8 
 
 Intercondylar, 54 
 
 Lesser Sciatic, 13 
 
 Nasal, 15 
 
 Popliteal, 53 
 
 of Rivini, 298 
 
 Sacro-iliac, 13 
 
 Sacro-sciatic, 13 
 
 Sigmoid, 34 
 
 Supraorbital, 14, 37 
 
 Suprascapular, 46 
 
 Thyroid, 350 
 
 Ulnar, 50 
 Nuchal Crest, 17 
 
 Ligament, 61, 88 
 
 Lines, 17 
 
 Nuck's Canal, 381 
 Nucleus or Nuclei, Abducent, 204 
 
 Amygdalae, 179 
 
 Anterior, 193 
 
 Auditory, 204 
 
 Caudatus, 191 
 
 Cerebellar, 208 
 
 Cuneatus, 198 
 
 Dentate, 208 
 
 Dorsal, 210, 216 
 
 Emboliformis, 208 
 
 Facial, 204 
 
 Fastigii, 208 
 
 Fourth Ventricle, 212 
 
 Globosus, 208 
 'Gracilis, 198 
 
 Habenulse, 194 
 
 Hypo-thalamicus, 203 
 
INDEX 
 
 423 
 
 Nucleus, Lenticular, 192 
 
 Lentiformis, 192 
 
 Lentis, of Crystalline Lens, 288 
 
 Mesencephalic of Masticator, 202 
 
 Olivary, Accessory, 209 
 Inferior, 209 
 Superior, 204 
 
 Pontis, 204 
 
 Red, 197 
 
 Roof, 208 
 
 Stilling's, 208 
 
 Tegmenti Ruber, 197 
 
 Trigeminal, 204 
 Nuhn's Glands, 274 
 Nymphae, 377 
 
 OBEX, 212 
 Occipital Bone, 17 
 Odontoblasts, 319 
 Odontoid, 3 
 
 Process, 7 
 (Esophagus, 322 
 Olive, 209 
 Omenta, 326 
 Omentum, Gastro-colic, 326 
 
 Gastro-hepatic, 326 
 
 Gastro-splenic, 326 
 
 Great, 326 
 
 Lesser, 326 
 
 Opening, Saphenous, 108, 389 
 Optic Thalamus, 193 
 Ora Serrata, 285 
 Orbiculus Ciliaris, 283 
 Orbit, 35 
 Organ or Organa 
 
 Accessoria Oculi, 293 
 
 Auditus, 296 
 
 of Corti, 309 
 
 of Digestion, 312 
 
 of Equilibration, 309 
 
 of Generation, Female, 377 
 Male, 370 
 
 of Hearing, 296 
 
 of Jacobson, 278 
 
 of Orientation, 309 
 
 of Rosenmuller, 383 
 
 of Sight, 280 
 
 of Smell, 276 
 
 of Special Sense, 270 
 
 Spirale, 309 
 
 of Taste, 273 
 
 of Touch, 272 
 
 Urinary, 360 
 
 of Voice and Respiration, 350 
 
 Vomero-nasale, 278 
 Orientation, 309 
 Orificium Uteri, 380 
 Os or Ossa, see Bones 
 Ossicula Auditus, 301 
 Ossification, 4 
 Osteology, i 
 Ostium Arteriosum, 121 
 Pulmonis, 120 
 
 Venosum Ventriculi Sinistri, 121 
 Ptoconia, 307 
 Otoliths, 307 
 Ovaries, 382 
 
 Ovicapsule, 383 
 Oviducts, 382 
 
 PACCHIONIAN Bodies, 181, 182 
 Paccinian Corpuscles, 177, 272 
 Palate, 313 
 
 Bone, 31 
 
 Pampiniform Plexus, 375, 383 
 Pancreas, 3*13 
 
 Lesser, 344 
 Panniculus Adiposus, 74 
 
 Carnosus, 74 
 Papilla, Lacrimal, 294 
 Optic, 286 
 Spiralis, 309 
 
 Papillae Circumvallate, 274 
 Filiformes, 274 
 of Kidney, 361 
 of Mammae, 384 
 of Skin, 271 
 of Tongue, 274 
 Vallatae, 274 
 Paraganglia, 345 
 Parathyroid Glands, 346 
 Parietal Bone, 16 
 Parotid Gland, 315 
 Parovarium, 383 
 Pars Ciliaris Retinae, 285 
 
 Flaccida Membranae Tympani, 298 
 Intermedia, 220, 276 
 Iridica Retinae, 285 
 Patella, 54 
 
 Path, Optic-acustic Reflex, 199, 200 
 Pecten Ossis Pubis, 14 
 Pedicles, 5 
 
 Peduncles of Cerebellum, Inferior,2O7, 209 
 Middle, 204, 207 
 Superior, 201, 207 
 of Cerebrum, 195 
 Pelvis, 9 
 
 Cavity of, 391 
 Fasciae of, 391 
 of the Kidney, 363 
 Penis, 371 
 Pericardium, n8 
 Pericementum, 319 
 Perilymph, 304 
 Perinaeal, Body, 395 
 Fossae, 393 
 Interspaces, 393 
 Perinaeum, Proper, 391 
 Female, 395 
 Male, 392 
 Perineurium, 177 
 Periosteum, 4 
 Peritoneum, 325 
 Peroneal Bone, 55 
 Peroneus, 55 
 Pes Accessorius, 191 
 Anserinus, 220 
 Hippocampi, 191 
 Petiolus Epiglottidis, 352 
 Petit's Canal, 288, 289 
 Petro-mastoid Bone, 19 
 Peyer's Glands, 333 
 Phaerochrome System, 344 
 Phalanges, 52, 58 
 Pharyngeal Cushion, 321 
 
424 
 
 INDEX 
 
 Pharynx, 320 
 
 Pia Mater, 182, 213 
 
 Pillars of the Fauces, 314 
 
 of the Abdominal Ring, 386 
 Pjlli, 273 
 
 Pineal Gland, 194 
 Pinna of the Ear, 297 
 Pituitary Body, 186 
 Plate, Cribriform, 26 
 
 Orbital of Ethmoid, 26 
 of Frontal, 15 
 
 Perpendicular, 26 
 
 Tarsal, 294 
 Pleurae, 356 
 Plexus, Aortic, 2JT, 268 
 
 Brachial, 228, 256 
 Tabulated, 230 
 
 Cardiac, 239 
 ' Cartoid, 237, 268 
 
 Cavernous, 237, 268 
 
 of the Clitoris, 242 
 
 Cervical, 227 
 
 Choroid, 190 
 
 Cceliac, 240 
 
 Colic, Left, 241 
 
 Coronary, 239, 241 
 
 Cystic, 241 
 
 Diaphragmatic, 240 
 
 Epigastric, 240 
 
 Gastric, Inferior, 241 
 Superior, 241, 250 
 
 Gastro-duodenal, 241 
 
 Gastro-epiploic, 241 
 
 Gullae (oesqphageal) , 323 
 
 Haemorrhoidal, Inferior, 242 
 Superior, 241 
 
 Hepatic, 241, 300 
 
 Hypogastric, 241, 268 
 
 Interlobular, 342 
 
 Lienal, 241, 349 
 
 Lumbalis, 232 
 
 Lumbar, 232, 262 
 
 Mesenteric, Inferior, 241 
 Superior, 241 
 
 (Esophageal, 222, 250, 323 
 
 Olfactory, 279 
 
 Ovarian, 2^10, 241 
 
 Palatine, 315 
 
 Pampiniform, 375, 383, 
 
 Pelvic, 2di, 268 
 
 Pharyngeal, 237, 268, 315, 322 
 
 Phrenic, 240 
 
 Prostatic, 242 
 
 Pudendal, 234 
 
 Pulm9nary, 239, 268, 358 
 
 Pyloric, 2A I 
 
 Renal, 2^0, 263 
 
 Sacral, 233, 262 
 
 Sigmoid, 241 
 
 Solar, 240 
 
 Spermatic, 2di 
 
 Spinosus, 219 
 
 Splenic, 241, 349 
 
 Supra-renal, 240 
 
 Tympanic, 303 
 
 Uterine, 2J2 
 
 Vaginal, 242, 380 
 
 Vesical, 242 
 
 Plexuses of the Sympathetic, 239, 268 
 Plica or Plicae 
 
 Alares, 70 
 
 Arytaeno-epiglotticae, 352 
 
 Glosso-epiglotticae, 353 
 
 Lacrimalis, 296 
 
 Palmatse, 380 
 
 Recto-uterinae, 381 
 
 Semilunaris, 295, 314 
 
 Syriovialis Patellaris, 71 
 
 Transyersales Recti, 335 
 
 Ventriculares, 353 
 
 Vocales, 353 
 Point, Central Tendinous of Perinaeum, 
 
 394 
 
 Pomum Adami, 350 
 Pons Hepatis, 338 
 
 Tarini, 188 
 
 Varolii, 203 
 Porta Hepatis, 338 
 Portal System, 170 
 Porus Opticus, 286 
 Pouch, Douglas, 327 
 
 Laryngeal, 354 
 
 Peritoneal, 327 
 
 Recto-vaginal, 327, 366 
 
 Recto-vesical, 327, 366 
 
 Utero-vesical, 327, 366 
 
 Umbilical, 367 
 
 Poupart's Ligament, 108, 387 
 Praeputium, 372 
 Precuneus, 185 
 Prepuce of the clitoris, 377 
 
 of the Penis, 372 
 Process, Acromion, 46 
 
 Alveolar, 29 
 
 Angular, 15 
 
 Articular, 5 
 
 Auditory, 25 
 
 Basilar, 18 
 
 Clinoid, 22, 24 
 
 Condylar, 34 
 
 Coracoid, 46 
 
 Coronoid, 34, 49 
 
 Ethmoidal, 22 
 
 Falciform, 390 
 
 Frontal, 28 
 
 Fronto-sphenoidal, 30 
 
 Hamular, 25, 29 
 
 Jugular, 1 8 
 
 Lacrimal, 32 
 
 Malar, 28 
 
 Mastoid, 20 
 
 Maxillary, 32 
 
 Mental (mentum; chin), 33 
 
 Nasal, 28 
 
 Odontoid, 7 
 
 Olecranon, 48 
 
 Olivary, 22 
 
 Orbital, 30, 32 
 
 Palatine, 29 
 
 Pterygoid, 25 
 
 Pyramidal, 32 
 
 Sphenoidal, 32 
 
 Spinous, 6 
 
 Styloid, 21, 49, 50, 55 
 
 Transverse, 5 
 
 Turbinal, 26 
 
INDEX 
 
 425 
 
 Process, Unciform, 26 
 
 Uncinate, 26 
 
 Vaginal, 21 
 
 Vermiform, 206, 334 
 
 Zygapophyseal, 5 
 
 Zygomatic, 19, 28 
 Processes, Ciliary, 284 
 
 Clinoid, 23 
 
 of Ingrassias, 24 
 Processus, Anterior, 301 
 
 Cochleariformis, 21, 301 
 
 Gracilis, 301 
 
 Lateralis, 301 
 Prominence, Laryngeal, 350 
 
 Tuhal, 321 
 Promontory, of Cochlea, 300 
 
 of the Facial Canal, 300 
 
 of the Sacrum, n 
 
 of the Tympanum, 300 
 Prosencephalon, 178 
 Prostate Gland, 370 
 Protuberance, Occipital, 17, 1 8 
 Psalterium, 190 
 Pterygoid, 3, 25 
 Pubes, 14 
 
 Pudendum Muliebre, 377 
 Pulmones, 357 
 Pulpa Dentis, 318 
 
 Lienis, 349 
 Pulvinar, 193 
 Punctum Lacrimale, 294 
 Pupil or Pupilla, 285 
 Purkinje's Cells, 176, 208 
 Pylorus, 329 
 Pyramid of the Cerebellum, 207 
 
 of the Medulla, 209 
 
 Posterior, 210 
 
 of the Thyroid Gland, 345 
 
 of the Tympanum, 301 
 Pyramids of Ferrein, 362 
 
 of Malpighi, 362 
 
 of Wistar (sphenoidal turbinals), 24 
 
 QUADRATE Lobe, 338 
 
 Lobule (cuneus), 186 
 Quadratus Femoris, 112 
 
 Labii, 78 
 
 Lumborum, 97 
 
 Menti, 78 
 
 Suadriceps Femoris, 108 
 uadrigeminal Bodies, 202 
 
 RADIUS, 49 
 
 Rami, Communicantes, 227, 238 
 
 Ramus, Ischio-pubic, 12 
 
 mandibular, 34 
 Raph6 of Medulla, 211 
 
 of the Perinaeum, 392 
 
 of the Tongue, 274 
 Receptaculum Chyli, 172 
 Recess or Recessus 
 
 Atic, 300 
 
 Cochlearis, 305 
 
 Duodeno-jejunalis, 328 
 
 Ellipticus, 305 
 
 Epitympanic, 300 
 
 Ileo-caecalis, 328 
 
 Incudis, 300 
 
 Recess, Naso-palatine, 278 
 
 Sphaericus, 305 
 
 Spheno-ethmoidal, 277 
 Rectum, 335 
 Region or Regions, Abdominal, 95, 323 
 
 of the Arm, 100 
 
 Buccal, 78 
 
 Cervical, 80, 84 
 
 Cranial, 75 
 
 Dorsal, 86 
 
 of the Ear, 86 
 
 Epigastric, 324 
 
 of the Forearm, 102 
 
 Gastric, 324 
 
 Gluteal, no 
 
 of the Hand, 105 
 
 Hyoid, 8 1 
 
 Hypo-chondriac, 324 
 
 Hypo-gastric, 324 
 
 Hypo-thalamic, 202 
 
 Iliac, 324 
 
 Inguinal, 324, 385 
 
 Ischio-rectal, 97 
 
 Laryngeal, 86, 88 
 
 Lingual, 82 
 
 Lumbar, 324 
 
 Mandibular, 78 
 
 Maxillary, 77 
 
 Nasal, 77 
 
 Orbital, 76 
 
 Palatal, 183 
 
 Palmar, 105 
 
 Palpebral, 75 
 
 Pelvic, 97 
 
 Perineal, 98, 99 
 
 Pharyngeal, 83 
 
 Plantar, 116 
 
 Pre vertebral, 84 
 
 Pterygoid, 79 
 
 of Shoulder, 100 
 
 Suboccipital, 88, 93 
 
 Temporo-mandibular, 79 
 
 Thoracic, 93, 99 
 
 of Thigh, 112 
 
 Tympanic. 80 
 
 Umbilical, 324 
 
 Vertebral, 84, 85 
 Reil, Island of, 183 
 Renes, 360 
 R6te. Carpi, 135 
 
 Mucosum, 270 
 
 Testis, 374 
 
 Rcticular Formation, 211 
 Retina, 285, 286 
 Rhombencephalon, 203 
 Ribes, Ganglion of, 236, 268 
 Ribs (costae), 8 
 Ridge, of Aquseductus Fallopii, 300 
 
 Articular of Temporal. 19 
 
 Condylar of Humerus, 48 
 
 Crucial, 18 
 
 Gluteal, 13 
 
 Infra-temporal, 24 
 
 Inter-trocnanteric, 53 
 
 Mylo-hyoid, 34 
 
 Nuchal, 17 
 
 Pterygoid, 24 
 
 Suprameatal, 19 
 
426 
 
 INDEX 
 
 Ridge, Temporal, 16 
 Rima Glottidis, 353 
 
 Palpebrarum, 293 
 Ring, Abdominal, Deep, 385 
 External, 386 
 Internal, 385 
 Superficial, 386 
 
 Crural, 389 
 
 Femoral, 389 
 
 Inguinalis Abdominalis, 385 
 
 Subcutaneous, 386 
 Rivinius, Duct of, 316 
 
 Notch of, 298 
 Rods and Cones, 287 
 
 of Corti, 310 
 Rolando, Fasciculus of, 209 
 
 Fissure of, 184 
 Root, Descending or Mesencephalic of 
 
 the Trigeminal Nerve, 201 
 Rosenmiiller's Fossa, 322 
 
 Gland, 295 
 
 Organ, 383 
 Rostrum, 3 
 
 of the Sphenoid, 24 
 Rugae Vaginales, 379 
 
 SAC of Hilton, 354 
 
 Lacrimal, 296 
 
 Peritoneal, 325 
 Saccule, 304 
 Sacculus Laryngis, 354 
 Sacro-sciatic Foramen, 64 
 
 N9tch, 13 
 Santorini's Cartilages, 352 
 
 Muscle (risorius), 79 
 Saphenous Opening, 108, 389 
 Sapolini, on the Chorda Tympani, 276 
 Scala Media, 309 
 
 Tympani, 307 
 
 Vestibuli, 307 
 Scapha Auriculae, 297 
 Scaphoid Bone, 51, 57 
 Scapula, 45 
 Scarf-skin, 270 
 Scarpa's Fascia, 108, 385 
 
 Foramen, 29 
 
 Ganglion, 311 
 
 Triangle, 142 
 Schachowa's Tubes, 362 
 Schreger's Lines, 319 
 Schindylesis, 59 
 Schlemm's Canal, 282 
 Schultze's Olfactory Cells, 278 
 Schwann, Substance of, 177 
 Sclerotic, 281 
 Scrotum, 373 
 Sella Turcica, 22 
 Sense, Special, 270 
 Septum Canalis Musculo-tubarii, 301 
 
 Crurale, 389 
 
 Femorale, 389 
 
 Lucidum, 190 
 
 Narium, 276 
 
 Nasi, 276 
 
 Pectiniforme, 371 
 
 Pellucidum, 190 
 
 Transversum, 309 
 
 Tubae, 21 
 
 Sheath, Crural, 390 
 
 Femoral, 390 
 Shin-bone, 54 
 Shoulder, 44, 65 
 Shoulder-blade, 45 
 Shrapnell's Membrane, 298 
 Sight, Organ of, 280 
 Sigmoid Flexure, 334 
 Sinus, Coronary, 171 
 
 Maxillaris, 27 
 
 of Morgagni, 354 
 
 Pocularis, 368 
 
 Prostatic, 368 
 
 Renis, 361 
 
 Tonsillaris, 314 
 
 Venosus, 119, 282 
 Sinuses, of the Dura Mater, 164 
 
 Frontal, 15 
 
 Meningeal, 164 
 
 Sphenoidal, 23 
 
 of Valsalva, 120 
 
 Venous, 163 
 Skin, 270 
 
 Appendages of, 272 
 Skull, Base of, 41 
 
 Fossse of, 41, 42 
 
 Slit, Nasal (ethmoidal fissure), 38, 41 
 Smell, Organ of, 276 
 Socia Parotid is, 316 
 Space, Haversian, 4 
 
 Inter-peduncular, 189 
 
 Ischio-rectal, 394 
 
 Perforated, 186, 188, 193 
 
 Perinaeal, 393 
 
 Popliteal, 54 
 
 Subarachnoid, 181 
 
 Subdural, 181 
 Spaces of the Eyeball, 290 
 
 Fontana's, 282 
 Spatia Anguli Iridis, 282 
 
 Zonularia, 288, 289 
 Spermatic Cord, 376 
 Sphenoid Bone, 22 
 Sphincter Pupillae, 285 
 
 Vaginae, 99 
 
 Vesicae, 367 
 Spinal Cord, 213 
 Spine, Alar, 24 
 
 Ethmoidal, 22 
 
 Frontal, 15 
 
 of the Ilium, 13 
 
 of the Ischium, 13 
 
 Mandibular, 34 
 
 Nasal, 15, 29, 31 
 
 Pharyngeal, 18 
 
 of the Pubis, 14 
 
 of the Scapula, 45 
 
 of the Sphenoid, 22 
 
 of Spix (mandibular), 34 
 
 of the Tibia, 54 
 Spinous, 3 
 Splanchnology, i 
 Spleen, 348 
 Spot, Blind, 286 
 
 Yellow, 285 
 Squamous, 3 
 
 Bone, 19 
 Stapes, 301 
 
INDEX 
 
 427 
 
 Stenson's Duct, 316 
 
 Foramen, 29 
 Sternum, 8 
 Selling's Canal, 288 
 
 Roof Nucleus, 208 
 Stomach, 328 
 Stratum Cinereum, 202 
 
 Corneum, 270 
 
 Germinativum, 270 
 
 Granulosum, 270 
 
 Griseum Centrale, 197 
 Colliculi Superioris, 202 
 
 Intermedium, 197 
 
 Lemnici, 202 
 
 Lucidum, 270 
 
 Malpighii, 270 
 
 Opticum, 202, 286 
 
 Zonale, 202 
 Stria Terminalis, 190 
 Striae Acusticae, 212 
 
 Longitudinales, 190 
 
 Medullares, 212 
 
 Obliquae, 212 
 Stripe, Malleolar, 298 
 Styloid, 3 
 
 Process, 21 
 Submaxillary, now called Submandibu- 
 
 lar 
 Substantia Adamantina, 319 
 
 Alba, see White Matter, 177 
 
 Eburnea, 319 
 
 Gelatinosa (Rolandi), 204, 209 
 
 Grisea, see Gray Matter, 176 
 
 Ossea, 319 
 
 Perforata, 186, 188, 193 
 Sulci, 183, see also Grooves and Fissures 
 Sulcus Cerebri Centralis, 184 
 
 Chiasmatis, 22 
 
 Longitudinalis Medianus, 212 
 
 Medianus Linguae, 274 
 
 Nervi Oculo-motorii, 22 
 Radialis, 47 
 
 Sagittalis, 15 
 
 Spiralis Internus, 309 
 
 Tympanicus, 298 
 Supercilia, 293 
 Sustentaculum Tali, 57 
 Sutura, 59 
 Suture or Sutures 
 
 Coronal, 16, 40 
 
 Cranial, 40 
 
 Facial, 40 
 
 Lambdoid, 16 
 
 Metppic, 14 
 
 Orbital, 37 
 
 Sagittal, 16, 40 
 Sylvius, Aquaeduct of, 202 
 
 Fissure of, 184 
 
 Sympathetic System, 236, 268 
 Symphysis, 33, 59, 64 
 Synarthrosis, 59 
 Synovia, 60 
 
 Synovial Membranes, 60 
 Syndesmology, i, 58 
 Syndesmosis, 59 
 System, Arterial, 122 
 
 Cerebro-spinal Nervous, 178 
 
 Chromaffin, 344 
 
 System, Chromaphil, 344 
 Haversian, 4 
 Lymphatic, 171 
 Nervous, 175 
 Phaerochrome, 344 
 Portal, 170 
 
 Sympathetic Nervous, 236, 268 
 Vascular, 118 
 Venous, 163 
 
 TAPETUM, 283, 286 
 
 Tarsi, 294 
 
 Tarsus, 57 
 
 Taste, Nerves of, 275 
 
 Taste-buds, 275 
 
 Taenia Hippocampi, 190 
 
 Semicircularis, 190 
 Tectum, 202 
 
 Mesencephali, 202 
 Teeth, 31? 
 
 Development of, 319 
 
 Eruption of, 320 
 Tegmentum, 197 
 Tela Choroidea Inferior, 211 
 Ventriculi Tertii, 190 
 
 Subcutaneous, 74 
 Telencephalon, 178 
 Temporal Bone, 19 
 Tendo Oculi, 294 
 Tendon of Achilles, 113 
 
 Conjoined, 95 
 Tendons, 74 
 Tenon's Capsule, 280 
 Tentqrium Cerebelli, 181 
 Terminal Organs, 177 
 Testes, 392 
 
 Appendages of, 375 
 
 Coverings of, 373 
 
 Descent of, 375 
 
 Quadrigeminal, 202 
 Testicle, 392 
 Thalamencephalon, 192 
 Thalamus Opticus, 193 
 Thebesius, Foramena of, 119 
 Thenar Eminence, 106 
 Thigh, 112 
 Thorax, 7, 93, 99 
 Thymus Gland, 347 
 Thyro-hyal, 41 
 Thyroid (or thyreoid) Axis, 131, 152 
 
 Cartilage, 350 
 
 Gland, 345 
 Tibia, 54 
 Tissue, Erectile, 371 
 
 Gray Nervous, 176 
 
 White Nervous, 177 
 Todd and Bowman, Muscle of, 309 
 Tongue, 273 
 
 Muscles of, 82, 83 
 Tonsil, Cerebcllar, 207 
 
 Palatine, 314 
 
 Pharyngeal, 321 
 . Tubal, 303 
 
 Torcular Herophili, 18, 165 
 Torus Tubarius, 321 
 Trabeculse Lienis, 349 
 Trachea, 355 
 Tract, see also Fasciculus 
 
428 
 
 INDEX 
 
 Tract, Anterior (or direct) Pyramidal, 
 
 196, 214 
 Ascending Antero-lateral (Gower's), 
 
 205, 214 
 
 Caudate-cerebellar, 197 
 Central Tegmental, 202 
 Cerebro-spinal, 196, 214 
 Cortico-pontine, 19? 
 Crossed Pyramidal, 196, 214 
 Descending Root of Trigeminus, 
 
 201 
 Direct Cerebellar (Flechsig's), 210, 
 
 215 
 Direct (or anterior) Pyramidal, 196, 
 
 214 
 
 Flechsig's, 210, 215 
 Fronto-pontine, 197 
 Gower's, 205, 214 
 Indirect Motor, 197 
 Lissauer's, 215 
 Mesencephalic Root of Trigeminus, 
 
 2OI 
 
 Mesencephalo- (or tecto-) Spinal, 
 199 
 
 Monakow's, 201 
 
 Motor, Direct, 196 
 Indirect, 197 
 
 Postero-lateral, 215 
 
 Pre-pyramidal, 201 
 
 Pyramidal, 196 
 
 Rolando's, 209 
 
 Rubro-spinal, 201 
 
 Solitary, 211. 221 
 
 Spino-cerebellar, 205, 214 
 
 Spino-thalamic, 200 
 
 Tecto- (or mesencephalo-) Spinal, 
 199 
 
 Temporo-pontme, 197 
 
 Thalamo-olivary, 202 
 
 Transverse Peduncular, 180 
 
 Uncrossed Pyramidal, 196 
 
 Uveal, 281 
 
 Ventral Spino-cerebellar, 205, 206 
 
 Ventro-lateral Spino-cerebellar, 205, 
 
 206 
 
 Tractus Spiralis Foraminosus, 311 
 Tragus, 297 
 
 Trapezium Medullas Oblpngatae, 204 
 Triangle, Anterior, Cervical, 128 
 
 Carotid, 129 
 
 Femoral, 142 
 
 Habenular, 194 
 
 Hesselbach's, 387 
 
 Interosseous of Fibula, 56 
 
 Occipital, 130 
 
 Posterior Cervical, 130 
 
 Scarpa's, 142 
 
 Subclavian, 130 
 
 Subcutaneous of Fibula, 56 
 
 Submandibular, 129 
 
 Submaxillary, 129 
 Triangles of the Neck, 128 
 Trigonum Acustici, 212 
 
 Collaterale, 191 
 
 Femorale, 142 
 
 Habenulae, 194 
 
 Hypoglossi, 212 
 
 Olfactorium, 217 
 
 Trigonum Vagi, 212 
 
 Vesicse, 367 
 
 Triquetrum (cuneiform), 51 
 Trochanters, 3 
 
 of Femur, 53 
 Trochlea, of Humerus, 48 
 
 of the Orbit, 289 
 Trochlear, 3 
 
 Nerve, 217, 244 
 Trochoides, 59 
 Tuba Auditiva, 303 
 Tuba? Uterinae, 382 
 Tube or Tubes 
 
 Eustachian, 303 
 
 Fallopian, 382 
 
 Neural, 178 
 
 of Shachowa, 362 
 Tube-tonsil, 303 
 Tuber Cinereum, 186 
 
 Valvulas, 207 
 Tubercle or Tubercles, 3 
 
 Adductor, 54 
 
 Amygdaloid, 179 
 
 Anterior of the Thalamus, 193 
 
 Bicipital, 49 
 
 Darwin's, 297 
 
 Genial, 34 
 
 of Humerus, 47 
 
 of Lower, 120 
 
 Pharyngeal, 18 
 
 Zygomatic, 19 
 Tuberculum, Acusticum, 212 
 
 Auriculae, 297 
 
 Intervenosum, 120 
 
 Sellse, 22 
 Tube^sity or Tuberosities, 3 
 
 Bicipital, 49 
 
 of Femur, 54 
 
 of Humerus, 47 
 
 of Ischium, 14 
 
 Malar, 30 
 
 Maxillary, 28 
 
 of Palate, 32 
 
 of Radius, 49 
 
 of Tibia, 54 
 
 of Ulna, 49 
 Tubules or Tubuli 
 
 Convoluted, 362 
 
 Dentinal, 319 
 
 Lactiferi, 384 
 
 Renales, 362 
 
 Seminiferi, 374 
 
 Spiral, 362 
 
 Uriniferi, 362 
 Tuft, Malpighian, 361 
 Tunica Albugenia, 374 
 
 Conjunctiva, 294 
 
 Fibrosa Oculi, 281 
 
 Interna Oculi, 285 
 
 Ruyschiana, 283 
 
 Vaginalis Testis, 374 
 
 Vascu^sa Oculi, 283 
 
 Testis, 374 
 Tunics of the Eyeball, 281 
 
 of the Testicle, 374 
 Turbinals, 32 
 
 Sphenoidal, 24 
 Tutamina Oculi, 293 
 
INDEX 
 
 429 
 
 Tympanic Bone, 21 
 Tympanum, 300 
 Tyson's Glands, 372 
 
 ULNA, 48 
 
 Umbilical Region, 324 
 Umbilicus, 324 
 Umbo, 298 
 Unciform, 3 
 Uncinate Gyrus, 186 
 Ungues. 272 
 Urachus, 366 
 Ureters, 363 
 Urethra, Female, 370 
 
 Male, 368 
 
 Urogenital Diaphragm, 393 
 Uterus, 380 
 
 Appendages of, 382 
 
 Masculinus, 368 
 Utricle, 307 
 
 Utriculus Prostaticus, 368 
 Uvea, 285 
 Uveal Tract, 281 
 Uvula, 313 
 
 Cerebelli, 207 
 
 Vesicae, 367 
 
 VAGINA, 379 
 Vaginal, 3 
 
 Process, 21 
 Vallecula, 206 
 
 Valsalva, Sinuses of, 120, 122 
 Valve of Bauhin, 331, 334 
 
 Coronary, 120 
 
 Eustachian, 120 
 
 of Hasner, 296 
 
 Ileo-caecal, 331, 334 
 
 Mitral, 121 
 
 Pyloric, 329 
 
 of Thebesius, 120 
 
 Tricuspid, 120 
 
 of Vieussens, 203, 207 
 Valves, Aortic Semilunar, 121 
 
 of Houston, 335 
 
 of Kirkring, 332 
 
 Pulmonary, 120 
 
 Semilunar, 120, 122 
 Valvulae Coli, 334 
 
 Conniventes, 332 
 
 Sinus Coronarii, 120 
 
 Venae Cavae Inferioris, 120 
 Vas Aberrans, 373 
 
 Deferens, 375 
 
 Spirale, 309 
 Vasa Efferentia, 374 
 
 Recta, 374 
 
 Vasorum, 122 
 Vein or Veins, 163 
 
 Angular, 164 
 
 Auricular, 164 
 
 Axillary, 166 
 
 Azygps, 167 
 
 Basilic. 166 
 
 Bronchial, 356 
 
 Cardiac, 171 
 
 Cephalic, 166 
 
 Cerebellar, 164 
 
 Cerebral, 164 
 
 Veins, Choroid, 283 
 Cystic, 170 
 Emissary, 165 
 Facial, 164 
 Femoral, 168 
 Frontal, 163 
 Gastric, 170 
 Hepatic, 170, 3 2 
 Iliac, 169 
 Innominate, 166 
 Intercostal, 167 
 Interlobular, 342 
 Intralobular, 342 
 
 ugular, 165 
 ienal (splenic), 170 
 Lobular, 342 
 Lumbar, 170 
 Mammary, 167 
 Maxillary, 164 
 Median, 166 
 Mesenteric, 170 
 Occipital, 164 
 Ovarian, 170 
 Phrenic, 170 
 Popliteal, 1 68 
 Portal, 170, 341 
 Pulmonary, 163 
 Radial, 166 
 Renal, 170, 363 
 Saphenous. 168, 169 
 Spermatic, 170 
 Spinal, 168 
 Splenic, 170. 349 
 Subclavian, 166 
 Sublobular, 342 
 Supraorbital, 163 
 Supra-renal, 170 
 Temporal, 164 
 Thyroid, 167 
 Ulnar, 166 
 Uterine, 382 
 Vertebral, 166 
 Veins of the Abdomen, 169 
 Bladder, 368 
 Bone, 4 
 Diploe, 164 
 Ear, 312 
 
 Head and Neck, 163 
 Heart, 171 
 Intestine, 333, 336 
 Kidney, 363 
 Larynx, 354 
 Liver, 341, 342 
 Lower Extremity, 168 
 Lung, 359 
 
 Mammary Gland, 384 
 Membrana Tympani, 299 
 Neck, 165 
 Nose, 279 
 (Esophagus, 323 
 Ovaries, 383 
 Pancreas, 344 
 Pelvis, 169 
 Penis, 372 
 of Pharynx, 322 
 Prostate Gland, 37 
 Rectum, 336 
 Stomach, 330 
 
43 C 
 
 INDEX 
 
 Veins, Supra-renal Glands, 365 
 
 Testicle, 375 
 
 Thorax, 167 
 
 Thymus Gland, 347 
 
 Thyroid Gland, 346 
 
 Tongue, 275 
 
 Tonsil, 314 
 
 Trachea and Bronchi, 356 
 
 Tympanic Membrane, 299 
 
 Tympanum, 302 
 
 Upper Extremity, 166 
 
 Uterus, 382 
 
 Vagina, 379 
 
 Without Valves, 163 
 Velum, Inferior Medullary, 212 
 
 Interpositum, 190 
 
 Superior Medullary, 203, 207 
 Vena Cava, Inferior, 170 
 
 Superior, 168 
 Venae Comites, 163 
 
 Galense, 185 
 
 Proprise Renales, 363 
 
 Rectae, 363 
 
 Vorticosae, 290 
 Venous Sinuses, 163 
 
 System, 163 
 Portal, 170 
 Pulmonary, 163 
 Systemic, 163 
 Ventricle of Cerebellum, 211 
 
 Lateral, 189 
 
 Fifth, 191 
 
 Fourth, 211 
 
 Laryngeal, 354 
 
 Nasal, 277 
 
 Third, 189, 192 
 Ventriculus, 328 
 Vermis Cerebelli, 206 
 
 Superior, 207 
 Vertebrae, 5 
 
 Important Relations of, 7 
 Vertebral Aponeurosis, 90 
 Verumontanum, 368 
 Vesica Fellea, 3^3 
 
 Urinaria, 365 
 Vesicle, Graafian, 383 
 
 Vesicles of the Brain, 178 
 
 Seminal, 376 
 Vestibule of the Ear, 305 
 
 of the Larynx, 353 
 
 of the Mouth, 312 
 
 of the Nose, 277 
 
 of the Vulva, 378 
 Vidian Canal, 25 
 Vieussens, Valve of, 203, 207 
 Villi of the Intestine, 332 
 Vinculum Lingua?, 207 
 Viscera covered by Peritoneum, 327 
 Vocal Cords, 353 
 Vomer, 33 
 
 Vortex of the Heart, 118 
 Vulva, 377 
 
 WAGNER'S Corpuscles, 177 
 
 Wharton's Duct, 316 
 
 White Matter of the Brain, 179 
 
 Rami Communicantes, 227 
 Willis, Circle of, 128, 151 
 Winslow's Foramen, 326 
 
 Ligament, 70 
 Wirsung's Duct, 344 
 Worm, 207 
 
 Wormian Bones, 3, 40 
 Wrisberg's Cartilage, 352 
 
 Ganglion, 239 
 
 Ligament, 71 
 
 Nerve, 229 
 
 XYPHOID Appendix, 8 
 YELLOW Spot, 285 
 
 ZINN, Ligament of, 76 
 
 Zonule, 288 
 Zona Arcuata, 309 
 
 Pectinate, 309 
 Zonula Ciliaris, 288 
 Zonule of Zinn, 288 
 Zygapophyses, 5 
 Zygoma, 19 
 Zygomatic Bone, 30 
 
2A>V0J^ cp&. 
 
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