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THE LIBRARY 
 
 OF 
 
 THE UNIVERSITY 
 
 OF CALIFORNIA 
 
 PRESENTED BY 
 
 PROF. CHARLES A. KOFOID AND 
 
 MRS. PRUDENCE W. KOFOID 
 
^^NOW 
 
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A DESCRIPTION 
 
 OF 
 
 THE BONES, 
 
 TOGETHER WITH 
 
 THEIR SEVERAL CONNEXIONS WITH EACH OT.HER, AND 
 WITH THE MUSCLES; SPECIALLY ADAPTED 
 
 ?tuStnt!5 lit anatoma* 
 
 By JOHN F. SOUTH, 
 
 ASSISTANT-SURGEON TO ST. THOMAs's HOSPITAL. 
 
 ILLUSTRATED WITH NUMEROUS ENGRAVINGS BY BRANSTON. 
 
 THIRD EDITION, 
 
 ENLARGED AND CORRECTED. 
 
 LONDON : 
 
 SHERWOOD, GILBERT AND PIPER 
 PATERNOSTER ROW. 
 
 . 1837. 
 
 Z/^^M^ 
 
VIZETELI.Y, BaANSTON AND CO. PRINTERS, 
 FLKET STREET, LONDON. 
 
PREFACE. 
 
 St 
 
 In presenting to the Profession a Third Edition 
 of this Uttle Work, I trust that its altered form will 
 tend considerably to improve its usefulness. The 
 employment of pictorial illustration as auxiliary to 
 descriptive Anatomy, is now so general, and the 
 increased facihty it affords to the Student so fully 
 admitted, that I feel no apology necessary for the 
 introduction of Wood- cuts as explanatory of the 
 text. It is not intended to compete with the mag- 
 nificent " Osteographia " of Cheselden, which must 
 ever be considered one of the finest specimens of 
 engraving and anatomical fideht}" ; but the great 
 value and rarity of that noble work remove it 
 beyond the reach of most persons, and its large size 
 would, even if it were easily procured, render it 
 inconvenient for constant reference. 
 
 I have, therefore, availed myself of Mr. Bran- 
 ston's able assistance, in providing for the Student 
 a pocket companion on that section of Anatomy 
 
 iG3 
 
IV PREFACE. 
 
 which, if perfectly understood, renders every other 
 comparatively easy. The Drawings for the several 
 subjects, have been made from the bones them- 
 selves, and are not, as is commonly the case, 
 copied from other works, with the exception of 
 the frontispiece from Cheselden, and some parts of 
 the Ear, which have been taken from Soemmering's 
 great work, "De Auditu," and which are acknow- 
 ledged. 
 
 The entire section on the bony structure of the 
 Ear I have added more fully than at first intended ; 
 and I hope the description here given will remove 
 the difficulty so commonly felt in acquiring a 
 knowledge of that beautiful, though complicated 
 apparatus. 
 
 JOHN F. SOUTH. 
 
 2, Adelaide Place, London Bridge, 
 December 1, 1836. 
 
CONTENTS, 
 
 CHAP. I. 
 
 Page 
 
 Of the Skeleton 1 
 
 CHAP. II. 
 Of the Bones of the Trunk 4 
 
 CHAP. III. 
 Of the Upper Extremity 32 
 
 CHAP. IV. 
 Of the Lower Extremity 53 
 
 CHAP. V. 
 Of the Head 70 
 
 CHAP. VI. 
 Of the Sutures and the Basis of the Skull 101 
 
 CHAP. VII. 
 Of the Bones of the Face 116 
 
 CHAP. VIII. 
 Of the Orbits, Nostrils, Palate, and Ears 130 
 
 CHAP. IX. 
 Of the peculiarities of the Bony Structure of the Foetus 144 
 
DESCRIPTION 
 
 OF 
 
 THE BONES. 
 
 CHAPTER I. 
 
 Of the Skeleton. 
 
 The Bones are those hard parts of the Human Body 
 which are composed principally of phosphate, with a 
 small portion of carbonate of lime, deposited in an or- 
 ganized substance, consisting of gelatine, and plentifully 
 supplied with vessels, for the purpose of nourishment 
 and growth. 
 
 They serve as a frame-work to the soft parts ; pro- 
 tect the more important organs ; and afford a series of 
 levers, by means of which, through the agency of the 
 muscles, locomotion is performed. 
 
 The Bones together form 
 
 THE SKELETON, 
 
 which is said to be either natural or artificial. 
 
 It is called a natural skeleton, when the bones 
 are kept together by their natural ligaments ; but this 
 
2 
 
 A DESCRIPTION OF THE BONES. 
 
 kind is of little use for practical purposes, since the 
 extremities of the bones, which are very important, as 
 forming the joints, are so completely covered, that their 
 form cannot be seen. It, therefore, becomes necessary to 
 remove all the soft parts, and join the bones together with 
 wires; and thus is produced the artificial skeleton. 
 
 The Skeleton consists of two hundred and forty-nine 
 bones, which are divided into those of the Trunk, Ex- 
 tremities, and Head ; some of them are single, and 
 others in pairs. They are 
 
 
 CO 
 
 Si 
 
 r Vertebrae 24 
 
 Costag 24 
 
 Sternum 2 
 
 Ossa innominata 2 
 
 Os sacrum 1 
 
 — coccygis 1 
 
 f Claviculae 2 
 
 Scapulae 2 
 
 Ossa humeri 2 
 
 Ulnre 2 
 
 Radii 2 
 
 Ossa carpi 16 
 
 metacai'pi 10 
 
 Phalanges digitorum manus 28 
 
 Ossa sesamoidea 4 
 
 femoris 2 
 
 Patella? 2 
 
 Tibiae 2 
 
 Fibulae 2 
 
 Ossa tarsi 14 
 
 metatarsi 10 
 
 Phalanges digitorum pedis 28 
 
 Ossa sesamoidea 4 
 
 186 
 
r3 
 
 ^i 
 
 o 
 
 A DESCRIPTION OF THE BONES. 
 
 Brought forward 186 
 
 f Os frontis 1 
 
 Ossa parietalia 2 
 
 Os occipitis 1 
 
 Ossa temporum 2 
 
 Ossicula auditus 8 
 
 Os splienoides 1 
 
 — ethmoides 1 
 
 Ossa malarum 2 
 
 maxillaria superiora 2 
 
 nasi 2 
 
 lachrymalia 2 
 
 palatina 2 
 
 turbinata 2 
 
 Vomer 1 
 
 Os maxillare inferius 1 
 
 Dentes 32 
 
 ^Os hyoides 1 
 
 249 
 
 Before proceeding with the description of the Bones, 
 it will be necessary to speak of 
 
 THE TERMS 
 
 generally used in describing relative position, or the 
 relation which one part bears to another. 
 
 The anatomist supposes the body erect, with the 
 arms in such position that the palms of the hands are 
 turned forwards, and the lower extremities so placed, 
 that the knees and toes are directly in front. The 
 terms, by which relative position is usually denoted, 
 with their several senses, are as follow. By superior 
 and inferior, we signify higher and lower with respect 
 to the summit of the head; by anterior and posterior, we 
 denote the situation of the parts as nearer to the fore or 
 
 B 2 
 
4 A DESCRIPTION OF THE BONES. 
 
 the hinder surface of the body ; and by laterally to the 
 right or left^ we understand that the parts so described 
 approach the one side or the other. Inner and outer 
 express the relation of any given part or portion of the 
 lK)dy to an imaginary plane, assumed by anatomists for 
 the purpose of distinct conception or description, and 
 named by them the Median plane, it being supposed to 
 bisect the body into lateral halves, passing through the 
 middle of the head and trunk, and continued between 
 the inferior extremities : inner denotes an approach to, 
 outer a removal from, this imaginary plane. The terms 
 external and internal, without and within, are used only 
 in speaking of cavities. 
 
 CHAP. II. 
 
 Of the Bones of the Trunk, 
 
 The Trunk is composed of the Spine, Thorax, and 
 Pelvis. 
 
 1. THE SPINE, Columna Spinalis, 
 
 Consists of twenty-four bones called vertebrae, which 
 are piled one upon the other, the lowest resting upon the 
 sacrum, and the uppermost supporting the head. 
 
 THE VERTEBRA.' 
 
 Each VERTEBRA cousists of a body, seven processes, 
 a hole, and four notches. 
 
A DESCRIPTION OF THE BONES. 
 
 The body, corpus (1), is the thick strong part situated 
 in the front, of an irregular oval or rounded form ; flat 
 or shghtly concave above (a) and below (b), convex 
 laterally before (c, c), and hollowed behind {d), where 
 it forms part of the spinal hole. The processes 
 
 are, four articular, two transverse, and one spinous 
 process. 
 
 Of the articular processes, j)' articulares, which join 
 the back part of the body, and form the sides of the 
 spinal hole, the two superior (2, 2) have their articulating 
 surfaces facing backwards, and a little outwards, whilst 
 the two inferior (3, 3) face forwards, and rather inwards. 
 From the roots of the superior articular processes extend 
 outwards, or outwards and backwards, the transverse 
 processes, p. transversi (4, 4), very strong and thick, 
 which are particularly for the attachment of muscles. 
 From between the superior and inferior articular pro- 
 cesses extends backwards, or backwards and downwards, 
 the spinous process, p. spinosus (5) ; this is sharp above 
 (e), concave below (/), and more or less hooked down- 
 wards. 
 
6 
 
 A DESCRIPTION OF THE BONES. 
 
 By tlie junction of the processes with the back part 
 of the body of the vertebra, the spinal hole foramen ver- 
 tehrale (G) is formed, which is either triangular or round, 
 and through it passes the spinal marrow and its mem- 
 branes. The roots of the articular processes are hollowed 
 out above and below into notches (7, 7, 7, 7), of which the 
 inferior are very deep ; these, when the vertebrae are 
 fitted together, form holes on each side (see page 14), 
 through which the nerves pass from the spinal canal. 
 
 DIVISION OF THE VERTEBRiE. 
 
 The vertebrae are divided into three classes, the 
 CERVICAL, of which there are seven, forming the neck ; 
 the DORSAL, or those of the back, which are twelve in 
 number ; and the lumbar, or those of the loins, consist- 
 ing of five vertebrae. These three classes not only have 
 remarkable general peculiarities, but also among them- 
 selves differ from each other. 
 
 The cervical vertebra are smaller than the others; 
 
 their bodies (1) are longer from side to side ; the upper 
 surface {a) the largest, and concave laterally, the lower (h) 
 the smallest, and concave from behind forwards ; articular 
 processes oblique, the superior (2, 2) oval, slightly con- 
 vex, facing upwards and backwards ; the inferior (3, 3) 
 
A DESCRIPTION OF THE BONES. 7 
 
 also oval, slightly concave, facing downwards and for- 
 wards ; transverse processes (4, 4) short and thin, passing 
 directly outwards from the body, and from the roots of 
 the articular processes, having a hole (8, 8) in each for 
 the transmission of the vertebral artery, and bifurcated (g) 
 for the attachment of muscles; spinous process (5) 
 short, horizontal, and bifid (A) ; spinal hole large and tri- 
 angular (6) ; its upper edge sharp, its lower edge larger 
 than the upper, and slightly rounded : the notches (7, 7) 
 at the roots of the articular processes not so large as in 
 the other vertebrae. 
 
 The dorsal vertebrae diminish in size from the first 
 to the fourth or fifth, from which they increase to the 
 twelfth, which is the largest of all. The body (1) is longer 
 
 from before to behind, than from side to side, flat above («) 
 and below (6), and the inferior surface the largest ; at the 
 junction of the body with the arch, a half articular surface 
 on the upper and lower margin (9, 9) ; these, when the 
 vertebrae are put together, form an articular surface on 
 each side, between every two dorsal vertebrae to receive 
 the heads of the ribs : articular processes perpendicular 
 and flat, the two superior (2, 2) facing backwards and 
 
8 
 
 A DESCRIPTION OF THE BONES. 
 
 outwards, the two inferior (3, 3) forwards and inwards : 
 transverse processes (4, 4) strong, extending outwards 
 and backwards, having a concave articular surface (10, 10) 
 on the front of their points for the tubercles of the ribs ; 
 spinous process (5) much hooked downwards, triangular, 
 and sharp above and behind, hollowed before and below : 
 spinal hole (6) round, notches larger than in the cervical 
 vertebrae. 
 
 The lumbar vertebra are of larger size than the 
 
 others, broader than their depth ; their long axes from 
 side to side, and slightly concave from behind to before, 
 both above and below : articular processes perpendicular, 
 the two upper (2, 2) concave, facing backwards and 
 inwards, the two lower (3, 3) convex, facing forw'ards 
 and outwards : transverse processes (4, 4) slender, and 
 passing backwards and outw^ards, inclining at the same 
 time rather upwards : spinous process (5) deep, long, 
 horizontal, and flattened at the sides : spinal hole (6) 
 triangular : notches large. 
 
A DESCRIPTION OF THE BONES. 
 
 9 
 
 Differences' IN particular VERTEBRiE of each 
 Division. 
 
 ^ Among the cervical vertebra, the first, second, 
 and seventli differ from the others. 
 
 The first vertebra, or Atlas, scarcely resembles a 
 vertebra, consisting merely of a bony ring, the ante- 
 
 rior part of which is hollowed out in place of the body 
 (1), for the dentiform process of the second vertebra, 
 and has an articular surface on its posterior surface (i) 
 for the front of that process ; the superior articular 
 processes (2, 2) irregularly oval, their long axes from 
 behind to before, concave in the same direction, and 
 facing upwards and inwards ; the inferior (3, 3) broad, 
 and nearly flat, facing downwards and inwards : trans- 
 verse processes (4, 4) not bifid but large, and originating 
 from between the upper and lower articular processes, 
 inclining shghtly downwards ; a groove {j) extending 
 on each side from the back of the hole (8, 8) in the 
 transverse process, along the upper edges of the arch, 
 and winding round the back of the roots of the upper 
 articular processes for the vertebral artery to make its 
 turn : spinal hole (6) large : notches situated behind the 
 roots of the articular processes. 
 
10 
 
 A DESCRIPTION OF THE BONES. 
 
 The second vertebra, Axis vel Vertebra Dentatay is 
 ^^ remarkable for a strong tooth-like 
 
 process or pivot, the dentiform pro- 
 cess, p, dentatus (11), which rises 
 from the upper part of tlie body (1), 
 
 *^ j^'-i^^Mn^^U has an oval articular surface (A;) on 
 
 its front, and is received into the 
 hollow of the Atlas : the superior articular processes (2) 
 very broad and nearly flat, face upwards and outwards, 
 and are situated immediately to the outside of the denti- 
 form process ; the inferior (3) placed below and behind 
 them, face forwards and downwards : the transverse 
 processes (4) very small and single, originate from the 
 outsides of the superior articular processes ; the holes (8) 
 in them not perpendicular, but passing upwards and 
 outwards : the spinal hole large : the superior notches 
 behind the upper articular, the inferior before the lower 
 articular processes. 
 
 The seventh vertebra diflTers from the other cervical, 
 '^ in being larger, in having the 
 transverse processes (4, 4) single, 
 with a hole in each for the trans- 
 mission of the vertebral veins, 
 and a smooth surface on the 
 front of their roots, over which the 
 vertebral artery passes to enter 
 into the holes in the transverse 
 processes of the sixth ; and in the spinous process (5) 
 not being bifid but longer, and slightly hooked down- 
 wards like the dorsal. 
 
A DESCRIPTION OF THE BONES. 
 
 11 
 
 Among the dorsal VERXEBRiE, the first, tenth, eleventh, 
 and twelfth differ from the others. 
 
 The jirst has a whole articular surface (12) on each 
 
 side of the body for the heads 
 of the first pair of ribs, besides 
 the half surfaces (9) for the 
 second pair. 
 The tenth (X) has but one pair of half articular sur- 
 faces (9) on the body for 
 the tenth pair of ribs. The 
 eleventh (XI) and twelfth 
 (XII) have whole articular 
 surfaces (12, 12) for the two 
 lowest pairs of ribs ; the 
 transverse processes (4) di- 
 minish gradually in size, so 
 that those of the twelfth are 
 the smallest, and those pro- 
 cesses of the eleventh and 
 twelfth have no articular 
 surfaces upon them : the 
 twelfth is further distin- 
 guished by having its inferior articular processes (3) con- 
 vex laterally, and facing forwards and outwards. 
 
 Among the lumbar vertebra, the fifth differs in 
 
 having the lower surface 
 (6) oblique instead of flat, 
 so that the anterior edge (c) 
 of the body is much deeper 
 than the posterior (c?); and 
 the spinous process (5) is 
 much hooked downwards. 
 
 X!I 
 
12 
 
 A DESCRIPTION OF THE BONES- 
 
 General Remarks on the Spine. 
 
 ■m 
 
 The vertebrae, when articulated to- 
 gether, form the Spine or Vertebral 
 Column, which measures about one- 
 third of the total height of the body, 
 the other two-thirds being made up of 
 the head, pelvis, and lower extremities. 
 With regard to the proportions which 
 the different divisions of the Spine bear 
 to each other, the dorsal division will 
 be found about two inches shorter than 
 the cervical and lumbar divisions taken 
 together. 
 
 When viewed in front, the Spine 
 appears of a pyramidal figure, the base 
 of it resting upon the sacrum, and the 
 apex supporting the head : but the apex 
 is not the most tapering part ; the bodies 
 of the vertebrae gradually diminish in 
 size, from the last lumbar up to the 
 fourth or fifth dorsal, and from that 
 they begin to enlarge up to the last 
 cervical, from which again they diminish 
 to the second cervical, which is very 
 large in comparison with the four ver- 
 tebrae immediately below it ; and above 
 that, the transverse processes of the 
 first vertebra are seen much expanded 
 beyond those of the other cervical ver- 
 tebrae. With respect to the diminution 
 of size in the middle of the dorsal ver- 
 
A DESCRIPTION OF THE BONES. 
 
 13 
 
 m'l^. 
 
 /A 
 
 rv~ 
 
 tebrae, it is probably intended to give 
 room for the important viscera contained 
 in the Thorax, of which they form a 
 large part of the posterior boundary ; 
 and to this end some anatomists have 
 described a curve on the left side to 
 give room for the aorta. M. Beclard, 
 however, has shown that this circum- 
 stance merely depends upon the use of 
 the right arm ; for in persons who were 
 left-handed, he found the curvature in 
 the opposite direction. 
 
 In looking at the Spine posteriorly, 
 the spinous processes are seen project- 
 ing in the middle ; those of the cervical 
 and lumbar vertebrae horizontally back- 
 wards, and those of the dorsal hooked 
 downwards ; on each side of these is 
 seen a groove, formed by the junction 
 of the arches of all the vertebrae, and 
 bounded on the outside by the trans- 
 verse processes, in which lie nearly all 
 the muscles contained in the vertebral 
 region. These being prominent in the 
 recent state, leave a depression between 
 them, in which the points of the spinous 
 processes are felt extending from the 
 head to the sacrum. 
 
 A lateral view of the Spinal Column 
 presents anteriorly, two convexities and 
 a middle concavity, the superior con- 
 vexity formed by the lower cervical and 
 
H 
 
 A DESCRIPTION OF THE BONES. 
 
 f 
 
 cales 
 
 upper dorsal vertebrae, and the infe- 
 rior by the lumbar ; whilst the middle 
 concavity is produced by the retro- 
 cession of the bodies of the middle 
 dorsal vertebrae. Behind the bodies 
 of the vertebrae, and between them 
 and the roots of the articular pro- 
 cesses, are seen the holes formed by 
 the junction of the notches, through 
 which the nerves pass from the spinal 
 canal. And the different directions 
 of the spinous processes may also be 
 well seen in this view. 
 
 The Spinal Canal, Canalis Verte- 
 bralis, is formed by the junction of 
 the arches of all the vertebrae ; it is 
 situated behind their bodies, and 
 bounded by the roots of all the pro- 
 cesses laterally and posteriorly ; it 
 forms a complete bony case for the 
 spinal marrow, protecting it in its 
 passage from the cranium to its ter- 
 ^j mination in the sacrum : it is largest 
 -0M\ in the cervical and lumbar vertebrae ; 
 and smallest in the dorsal. 
 
 The muscles attached to the spine 
 
 are, on the back part, M. trapezii, 
 
 ^^^s!^^^^"^!™ latissimi dorsi, rhomboidei majores 
 
 ^ & minores, levatores scapulae, serrati 
 
 postici superiores & inferiores, sple- 
 nii, complexi, sacro-lumbales, cervi- 
 descendentes, trachelo-mastoidei, longissimi dorsi. 
 
 
 ^^^'^v*! 
 
 'if 
 
A DESCRIPTION OF THE BONES. 
 
 15 
 
 transversales colli, spinales & semispinales dorsi, semi- 
 spinales colli, recti capitis postici majores & minores, 
 obliqui capitis superiores & inferiores, multifidi spinae, 
 interspinales, intertransversales, & levatores costarum ; 
 on the fore party M. longi colli, recti capitis interni 
 majores & minores, recti capitis laterales, scaleni antici, 
 medii & postici, diaphragma, qiiadrati lumborum, psose 
 magni & parvi, obliqui interni & transversales abdominis. 
 
 2. THE CHEST, Thorax, 
 
 Is formed by twelve pairs of ribs, two bones of the 
 STERNUM, and the twelve dorsal vertebrae already 
 described. 
 
16 
 
 A DESCRIPTION OF THE BONES. 
 
 THE RIBS. Costce. 
 
 Situation. They are placed on each side of the dorsal 
 vertebrae, and form with them the posterior and lateral 
 parts of the Thorax. They are divided into true, false, 
 and floating ribs ; of these the true, the seven superior, 
 are articulated to the sternum ; whilst the false, the 
 three below the true, join by their cartilages to each 
 other ; and the floating ribs, or two lowest, have their 
 anterior extremities unattached to each other and termi- 
 nating in the muscles. 
 
 JDescriiition. The form of the ribs is very irregular. 
 
 Each rib consists of two extremities with an inter- 
 mediate body, which is more or less curved forwards 
 and inwards, flat without (a) and within, (6) rounded 
 above (c) and sharp below {d), with a groove (e) along 
 its inferior edge for the intercostal vessels and nerves ; 
 the posterior or vertebral extremity is called the head (1), 
 which has two articular surfaces (2, 2) [upon it divided 
 
A DESCRIPTION OF THE BONES. 
 
 r 
 
 by a middle ridge (3), to articulate with the bodies of 
 
 the dorsal vertebrae ; imme- 
 diately to the outside of the 
 head, the bone is contracted 
 T^^.T''^ to form the neck (4), which 
 is marked by the capsular 
 hgament ; a little to the outer, 
 under, and back part of the 
 neck is the tubercle (5), having 
 a plane articular surface (C) for the transverse pro- 
 cess of the vertebra ; further outward, the bone be- 
 comes suddenly bent forwards, and produces the angle 
 (7) ; from which proceeds the body (8, 8), which passes 
 forwards and inwards, inclining at the same time down- 
 wards, to terminate at the sternal extremity (9), which 
 becomes deeper, and has an oval concave surface (10) in 
 which the cartilage is received. 
 
 Differences in Particular Ribs. 
 
 No two pairs of ribs resemble each other in length, or 
 in the direction of their curvature ; the first pair is the 
 shortest, the second longer than that, and so on till the 
 seventh pair ; when they begin again to decrease in length 
 to the twelfth, which is nearly as short as the first pair : 
 and with regard to the direction of their curvature, that 
 of the first is nearly horizontal, whilst the lower pairs dip 
 down more and more at their points. But there are other 
 more remarkable distinctions in the first, eleventh, and 
 twelfth ribs. 
 
 The first rib is very short and much curved; its 
 body (8, 8) is very thin, and broad above and below, with 
 
18 
 
 A DESCRIPTION OF THE BONES. 
 
 a smooth and slightly hollowed surface near its sternal 
 
 extremity, over which the sub- 
 clavian artery passes ; its head 
 (1) has only a single articular 
 surface (11) by which it joins to 
 the whole articular surface on the 
 side of the body of the first 
 dorsal vertebra ; and the tubercle (5), which is very large, 
 is placed immediately upon the angle (7) of the bone, so 
 that some anatomists describe it as wanting the angle. 
 
 The eleventh and twelfth ribs are shorter than all the 
 others, except the first; their heads (11, 11) have only 
 
 single articular surfaces to join with the whole articu- 
 lar cavities on the sides of the lowest dorsal vertebrae, 
 and have no angles; their anterior extremities (10) 
 although tipped witli cartilage, are not attached to the 
 cartilages of the other ribs, but are floating amongst the 
 muscles, from whence they have been c3\\g<\ floating ribs ; 
 and not having tubercles, they are not connected with the 
 transverse processes of the vertebrae. 
 
 The muscles attached to the ribs are the i\I. pectorales 
 majores and minores, subclavii, sterno-thyroidei, scaleni 
 antici, medii & postici, latissimi dorsi, serrati majores 
 
A DESCRIPTION OF THE BONES. 19 
 
 antici, superiores & inferiores postici, sacro-lumbales, 
 accessorii ad sacro-lumbalem, longissimi dorsi, levatores 
 & depressores costarum, intercostales, sterno-coslalis, 
 diaphragma, obliqui externi & interni, tranversales & 
 recti abdominis, & quadrati lumborum. 
 
 THE BREAST-BONE. Sternum. 
 
 Situation, In the front of the chest and connected 
 with the ribs and clavicles. It consists of two bones. 
 Descrijotion. The frst hone is of a triangular shape, 
 
 the base (1) of which is above, very thick, and forms the 
 fore and upper bomidary of the chest ; the apex (2) below 
 and truncated, having an irregular articular surface for 
 the second bone : it is irregularly convex before (a) and 
 concave behind (6) : at the top, on each point (3, 3) is an 
 articular surface, concave from side to side for the sternal 
 extremities of the clavicles, and between them the top of 
 the bone is rounded : on each side and below these, is a 
 large whole articular surface (4, 4) for the cartilages of the 
 first pair of ribs : the sides of the bone become contracted, 
 and at the lower part is a half articular surface (5, 5) for 
 the second rib. 
 
 The second bone is long and narrow, flat before (a) 
 and behind (b) : at the top it has an articular surface (1) 
 for the first bone, and below, a smaller one (2) for the 
 
 c 2 
 
20 
 
 A DESCRIPTION OF THE BONES. 
 
 ensiform cartilage, which has a half articular surface for 
 the seventh rib, and in old people is converted into bone : 
 on either side it has four whole concave articular sur- 
 faces (3, 4, 5, 6) for the third, fourth, fifth, and sixth ribs, 
 
 and two half ones for the second and seventh, that at the 
 upper part (7) being for the second, and that at the 
 lower (8) for the seventh, which is not very distinct from 
 the whole one for the sixth rib. 
 
 The muscles attached to the sternum are the M. pec- 
 torales majores, sterno-mastoidei, sterno-hyoidei, sterno- 
 thyroidei, sterno-costalis, & intercostales interni. 
 
 General View of the Thorax. 
 
 The Thorax, composed of the dorsal vertebrae, ster- 
 num, and ribs with their cartilages, resembles a cone, the 
 base of which is below, and the apex above : the base is 
 very wide, particularly in a transverse direction, and is 
 remarkable for a deep notch, which is bounded laterally 
 by the margins of the cartilages of the ribs, and has pro- 
 jecting into it from above, the point of the ensiform car- 
 
A DESCRIPTION OF THE BONES. 
 
 21 
 
 tilage : the apex is truncated, leaving an oval opening, 
 which is longest from side to side, through which pass the 
 trachaea, the oesophagus, the great vessels of the upper 
 extremities and head, and the nerves of the thoracic and 
 abdominal viscera. 
 
 As to the relative proportions of the thorax in the 
 male and female, in the former it is highest, and in the 
 latter widest. 
 
 3. THE PELVIS 
 
 Is the large bony cavity situated at, and forming the 
 lowest part of the trunk, by means of which its weight is 
 transmitted to the lower extremities. It consists of a 
 pair and two single bones, the ossa innominata, os 
 SACRUM, and os coccygis. 
 
 UNNAMED BONES, Ossa Innominata, 
 A pair. 
 
 Situation. On the sides and front of the Pelvis. 
 Each Os Innominatum is usually described as consisting 
 
oo 
 
 A DESCRIPTION OF THE BONES. 
 
 of three portions, viz., os ilii, os ischii, and os pubis, 
 into which it is found divided in the young subject : but 
 at the age of puberty or soon after, the three pieces be- 
 come united and form one bone. 
 
 a. Hip-bone. Os lUi (I.). 
 
 Situation, At the upper and outer part of the pelvis, 
 and forming the projection called the Hip. 
 
 Description. The lower part of the bone, forming the 
 upper part of the acetabulum (\\ or articular cavity, for 
 the head of the thigh bone, has above it a smooth sur- 
 
 face (2), over which the M, psoas magnus & iliacus pass 
 from the abdomen : bounding this to the outer side, and 
 above, is the inferior anterior spinous process, p. spino- 
 sus anterior inferior (S), to which one head of the M. 
 rectus femoris is attached ; above it is a notch (4) 
 bounded superiorly by the superior anterior spinous pro- 
 cess, j). spinosus anterior superior [5), to which the M. 
 tensor vaginae femoris & sartorius are attached : extend- 
 ing backwards and upwards, and then backwards and 
 downwards is the crest, crista (G, 6), which has an inner 
 
A DESCRIPTION OF THE BONES. ^3 
 
 and outer lip, labium internum (7) et externum (8), to 
 which the M. obliquiis externus & interims, & transver- 
 sahs abdominis, qiiadratus hmiborum & latissimus dorsi 
 are attached : the crest is terminated behind by the su- 
 perior posterior spinous process, p. spinosus posterior 
 superior (9) : below which is a small notch (10) bounded 
 inferiorly by the inferior posterior spinous process, p. 
 spi}iosus posterior inferior {11) : and from between the 
 two processes originate the M. sacro-lumbalis & longis- 
 simus dorsi : before this the bone appears cut out to form 
 part of the greater ischiatic notch, incisura ischiatica 
 major (12), and from thence begins the Ischium : on the 
 inside of the posterior spinous processes, is a large irre- 
 gular articular surface for the sacrum (13), with which it 
 forms the sacro iliac symphysis, or bird's head articula- 
 tion. The ilium is of an irregular fan-like shape, the 
 handle of which forms the upper part of the aceta- 
 bulum ; it is irregularly convex without («), and this part 
 is called the back, dorsum, which is marked by a curved 
 line (14) extending in a curved direction from the superior 
 anterior spinous process to the middle of the ischiatic 
 notch, below which the M. gluteus minimus arises, and 
 above it the M. gluteus medius : the inside (6) is called 
 the belly, venter, it is concave and smooth, giving origin 
 to the M. iliacus ; from the middle of the articular surface 
 for the sacrum, an obtuse edge extends forwards to 
 the junction of the bone with the os pubis, as if the 
 bone were pinched up ; it forms part of the brim of the 
 pelvis, Unea iliopectinea (15), into which the M. psoas 
 parvus is inserted. 
 
24 A DESCRIPTION OF THE BONES. 
 
 /S. The Haunch-bones. Os Ischii, 
 
 Situation. At the outer and under part of the pelvis, 
 and forming the back and under part of the acetabulum. 
 Description. Continuous from that part of the ischi- 
 atic notch (12), at which the ilium terminates, is the 
 
 Ischium, forming the front 
 of the greater notch, the 
 lowest boundary of which is 
 marked by a blunt spinous 
 process, p. spinosus (16) 
 giving origin to the superior 
 head of the M. gemini & coccygeus and the anterior sacro- 
 ischiatic ligament, opposite to which the bone is very thick, 
 forming the back and under part of the acetabulum (1). 
 Below the spinous process is another notch, the lesser ischi- 
 atic notch, incisura ischiatica minor {17), bounded below 
 by the broad tuberosity, tuber (IS), which has an irregu- 
 lar surface upon it, broadest behind and covered with 
 cartilage, upon which Ave sit, and giving origin to the 
 abductor and adductor muscles of the thigh and the 
 flexors of the leg : on the inside of the tuberosity is a 
 groove (19) in which the pudic artery and vein lay ; above 
 the tuberosity, between it and the under part of the 
 acetabulum, is a groove (20), over which the tendon of 
 the M. obturator externus plays : extending forwards and 
 upwards is the leg, cms (21), obtuse within, where it 
 gives attachment to the crus penis and M. erector penis ; 
 and sharp without, where it forms part of the foramen 
 obturator; and about the middle of this, on its inner side, 
 it terminates in the crus of the os pubis. 
 
A DESCRIPTION OF THE BOXES. 25 
 
 y. The Share-bone. Os Pubis. 
 Situation. In the front of the pelvis, and forming 
 the inner and under part of the acetabulum. 
 
 Description. Continuing upwards from the crus of 
 the ischium, is the leg, cms (22), of the Pubis, the outer 
 
 edge (23) of which forms 
 part of the obturator fora- 
 men, and the inner rough ' 
 to form the symphysis (24) 
 or junction of the two ossa 
 innominata : at right angles 
 with the crus, and extending outwards, is the angle, an- 
 gulus (25), immediately before which is the spinous pro- 
 cess, p. spinosus (26), to which Poupart's ligament is 
 attached ; extending outwards is the body, corpus (27), 
 smooth above, forming the flat surface over which the 
 iliac vessels and the anterior crural nerve pass ; sharp 
 below to form the upper part of the obturator foramen, 
 and sharp behind (14) to complete the linea iliopectinea : at 
 the outer extremity, the body becomes thick and hollowed 
 to form the fore and under part of the acetabulum (1). 
 
 The muscles attached to and covering the os innomi- 
 natum, are the M. psoas magnus & parvus, iliacus, levator 
 ani, obturator internus, pyriformis, coccygeus, obliquus 
 externus & internus, transversalis, rectus & pyramidalis 
 abdominis, quadratus lumborum, longissimus dorsi, sacro- 
 lumbalis & latissimus dorsi, tensor vaginas femoris, sarto- 
 rius, gluteus maximus, medius & minimus, rectus femoris, 
 gemini, quadratus femoris, biceps flexor cruris, semiten- 
 dinosus & semimembranosus, transversus perinaei, & 
 transversus perinaei alter, erector penis vel clitoridis, tri- 
 ceps adductor femoris, gracilis, pectineus & obturator 
 externus. 
 
26 
 
 A DESCRIPTION OF THE BONES. 
 
 The Rump-bone. Os Sacrum. 
 
 Situation. In the back of the pelvis, supported by 
 the ossa innominata on the sides, and receiving the Ver- 
 tebral Column above. 
 
 Description. The sacrum is of a triangular shape, its 
 
 base (1) facing upwards and forwards, its apex, which is 
 truncated (2), also facing forwards : it is concave before (6) 
 from above downwards, and irregularly convex behind («) 
 in the same direction : in the young subject it consists of 
 five pieces, which, from their general resemblance to the 
 vertebrae, have been called the false vertebrae, but in the 
 adult they are anchylosed into a single piece : in the an- 
 terior concave surface are four transverse lines (3, 3, 3,3) 
 marking the original separation into the five bodies, and 
 on each side of these are the four anterior sacral holes, 
 foramina sacralia anteriora (4, 4, 4, 4), bounded by the 
 transverse processes, p. transversi (5) ; the upper trans- 
 verse processes very broad, and having a notch (6, 6) 
 between them and the articular surface on the base, to 
 form part of the holes for the last pair of lumbar nerves : 
 on the base or upper part, an oval articular surface (7), 
 its long axis from side to side, and facing upwards and 
 forwards for the body of the last lumbar vertebra : the 
 
A DESCRIPTION OF THE BONES. 27 
 
 apex or lowest part having an oval articular surface (8) 
 for the OS coccygis, and a notch (9, 9) on each side of it 
 for the last pair of sacral nerves : on the posterior sur- 
 face, at the top, are seen the articular processes {x, x), 
 which receive those of the last lumbar vertebra: in 
 the middle are four processes, answering to the spinous 
 processes (10) of the vertebrae, which are generally 
 bifid, and occasionally so completely as to leave the 
 spinal canal open, and this is generally the case with 
 the two lowest : on either side of these are four holes, 
 foramina sacralia posteriora (11), for the passage of 
 small branches of nerves and vessels : the sides of the 
 sacrum are of an irregular triangular shape with the 
 base above, and having an articular surface (12) for the 
 OS innominatum. In consequence of the base of the 
 sacrum facing forwards and upwards, the anterior margin 
 projects considerably, and this is called the promontory (13) 
 of the sacrum. 
 
 The muscles attached to the sacrum are the M. latis- 
 simi & longissimi dorsi, sacro-lumbales, multifidi spinse, 
 glutei maxuni, pyriformes & coccygei. 
 
 Si-*! 
 
 The Coccyx. Os Coccygis, 
 
 Situation. At the tip of the os sacrum. 
 
 Description, The Coccyx consists of three or four 
 pieces (1, 2, 3, 4), in shape resembling the sacrmu, and 
 moveable upon it, and one an- i^,^*. k>^^^~^ ^ 
 other, till late in life, when they 
 become anchylosed into a single 
 bone : the upper is the largest, 
 and the lower the smallest piece ; they have plain oval 
 
28 
 
 A DESCRIPTION OF THE BONES. 
 
 concave articular surfaces above and below for each 
 other ; the upper surface (5) of the first piece is the 
 largest, and receives upon it the point of the sacrum : be- 
 hind and to the outer sides of this surface are two little 
 horns, cornua (6, 6), giving attachment to ligaments : the 
 lowest point of the last piece is rounded : the lateral edges 
 answering to transverse processes are thin and sharp : 
 neither piece is perforated by the spinal canal. 
 The muscles attached to it are the M. coccygei. 
 
 General View of the Pelvis. 
 
 The Pelvis, composed of the ossa innominata, os sa- 
 crum, and OS coccygis, is divided into two cavities by the 
 linea iliopectinea, which extends from the front on either 
 side as far as the sacro-iliac symphysis, sharp before and 
 obtuse behind. 
 
 The upper cavity, or false j^^lvis, is only partial, 
 being deficient in front ; its lateral and posterior parts are 
 formed by the bellies of the ilia, and the fore part is com- 
 
 Brim. 
 
 Female. 
 
 Male. 
 
 pleted by the abdominal muscles, against which the abdo- 
 minal viscera rest. 
 
A DESCRIPTION OF THE BONES. 
 
 29 
 
 The lower cavity, or true pelvis^ is bounded anteriorly 
 by the ossa pubis and ischii, laterally by the ossa ischii, 
 and a small portion of the ossa ilii, and posteriorly by the 
 OS sacrum and os coccygis. It contains in the male the 
 bladder and rectum ; and in the female, besides them, the 
 vagina and uterus. 
 
 The upper opening is called the brim, fades abdomi- 
 nalis {a, a, a, a) : its figure resembles the shape of the heart 
 painted on cards, the point of which is placed in front. 
 The diameter of the brim differs much in the male and 
 female pelvis, in the former it is greater from pubis to 
 sacrum, in the latter from ilium to ilium. 
 
 The lower opening is named the outlet, (b, b, b, b) it is 
 of an irregular diamond shape, and having the points be- 
 fore, behind, and on the sides : in the male it is compara- 
 
 Outlet. 
 
 Female. 
 
 Male. 
 
 tively small, but in the female very large, and within the lat- 
 ter the greatest extent is from pubis to sacrum, on account 
 of the sacrum not being so much curved as in the male. 
 
 The cavity, or true pelvis, is placed between the brim 
 and the outlet ; it is deepest posteriorly, not so deep la- 
 terally, and shallowest anteriorly. 
 
 Forming the front of the true pelvis are the pubes, 
 the junction of the rami of which at the symphysis pro- 
 
30 A DESCRIPTION OF THE BONES. 
 
 duces the arch of the pubis (c) ; this in the male is very 
 acute, but in the female it is obtuse for the purpose of 
 increasing the size of the outlet to facilitate delivery. 
 
 On each side of the arch of the pubis is the large ob- 
 turator hole, foramen obturator (d), formed by the ischium 
 and OS pubis : it is of an oval shape with the long axis 
 vertical, and its margin is very sharp for the attachment 
 of ligaments, except at the upper and outer part, where it 
 is rounded for the passage of the obturator artery, vein, 
 and nerve. 
 
 On each side and still further outwards is the arti- 
 cular cavity for the head of the thigh-bone, acetabulum (e), 
 formed by the junction of the ilium 
 (i.), ischium (ii.), and pubis (iii.): it 
 is of a deep cup-like shape, with its 
 concavity facing outwards and a little 
 downwards : its margin is not com- 
 pletely circular, but deficient at the 
 under and fore part forming a notch (/), which space 
 in the recent state is filled up with ligament; the upper, 
 outer, and under part of the acetabulum is smooth, but 
 opposite the notch it is scooped out, forming a cavity (g) 
 to which the round ligament is attached, surrounded by 
 a quantity of fat : the upper and outer part (h) of the 
 acetabulum, by which the weight of the body is transmit- 
 ted to the head of the thigh-bone, is the deepest, and the 
 under and fore part the shallowest. The proportions in 
 which the ilium, ischium and pubis enter into the com- 
 position of the acetabulum are, the upper and outer part 
 not quite two- fifths of the whole cavity by the ilium ; 
 the under part rather more than two-fifths by the 
 ischium ; and the fore part, one-fifth by the pubis. 
 
A DESCRIPTION OF THE BONES. 
 
 31 
 
 With respect to the axis of the pelvis, it is so placed 
 that the trunk does not rest upon the outlet, but upon the 
 tuberosities of the ischia, so that the outlet faces down- 
 wards and backwards, and the brim upwards and forwards, 
 
 in such way, that a line raised 
 perpendicular with the middle 
 of the brim, will pass upwards 
 and forwards through the um- 
 bilicus. This oblique bearing 
 of the pelvis is particularly 
 important in surgical and ob- 
 stetric practice connected with 
 the pelvis. 
 
 The differences between 
 the male and female pelvis, 
 may briefly be said to consist in the greater lateral dia- 
 meter of the brim, in the greater extent of the outlet, in 
 the greater width of the arch of the pubis, and the greater 
 distance between the acetabula in the female than in the 
 male. 
 
32 
 
 A DESCRIPTION OF THE BONES. 
 
 CHAP. III. 
 
 Of the Upper Extremity. 
 
 The Upper Extremity consists of the shoulder, 
 UPPER ARM, FORE ARM, and HAND ; tlicsc are connected by 
 the clavicle to the trunk, which is their only bony union ; 
 the other connections being by muscles. 
 
 1. THE SHOULDER. Scapula, 
 Consists of the clavicle and scapula. 
 
 THE CLAVICLE. Clavicle (I.). 
 
 Situation. At the upper part of the chest, horizon- 
 tally between the sternum and the scapula. 
 
A DESCRIPTION OF THE BONES. 
 
 33 
 
 Description. The clavicle, so called from its resem- 
 blance to an ancient key, is divided into body, two 
 extremities, two articular surfaces, and two processes. 
 
 Its shape is that of a small 
 Italic f, and it is placed 
 horizontally ; its inner or 
 sternal extremity (I) is very 
 large, and irregularly cylin- 
 drical ; upon its point is a 
 large articular surface (2), 
 by which it joins with the in- 
 terarticular cartilage placed between it and the sternum ; 
 about an inch from the sternal extremity on the under 
 edge is a rough surface, the rhomboid process, p. rhoni- 
 boides (3), by which it is attached to a ligament ; it then 
 becomes smooth and rounded, projects forwards, and 
 afterwards backwards, having the hole for the medullary 
 artery on its under surface, and about three-fourths from 
 the sternal extremity projects forward again, becomes 
 considerably expanded, and forms the scapular extremity 
 (4), which is the flattest part of the bone ; about an inch 
 and a half from the outer point, and on its under surface, 
 is a rough process called the tubercle, tuber (5), for the 
 attachment of ligaments ; and upon the outer part of the 
 scapular extremity a plane articular surface (6) for the 
 acromion of the scapula. 
 
 Connection, With the first bone of the sternum by 
 its inner, and with the acromial process of the scapula by 
 its outer extremity. 
 
 The muscles attached to the clavicle are six, to its 
 under part M. pectoralis major, deltoides, & subclavius ; 
 
34 A DESCRIPTION OF THE BONES. 
 
 and to its upper part M. trapezius, sterno-mastoideus, & 
 sterno-liyoideus. 
 
 THE BLADE BONE. Scapula (II). 
 
 Situation. On the posterior and superior part of the 
 chest. 
 
 Description. The scapula is of a triangular figure 
 consisting of three angles, three edges, three pits, three 
 processes, two articular surfaces, and two notches. 
 
 The inner and superior point is called the superior angle, 
 nngulus superior (1), the inner and inferior, the inferior 
 angle, angulus inferior (2), and the outer and superior, 
 the outer angle, angulus externus (3); the outer angle has 
 a slightly concave oval articular surface upon it called 
 the glenoid cavity, cavitas glenoides (4), by which the os 
 humeri articulates with the scapula, and around it the 
 bone is contracted and forms the neck, cervix (5) ; the 
 edges, costce, are the inner or base (6) between the 
 
A DESCRIPTION OF THE BONES. 35 
 
 superior and inferior angles, the inferior (7) between the 
 inferior and external angles, and the superior (8) between 
 the external and internal angles : the body of the bone 
 is divided behind or upon the dorsum (a) into two pits, 
 fossce, of which the inferior is the larger, by the spine 
 (13), the space above it is called the fossa sujnaspinata 
 (9), and that below it ihe fossa infraspinata (10) ; on the 
 inferior point of this is a triangular fiat surface (11) 
 immediately above the inferior angle, giving origin to 
 the M. teres major ; the front (h) of the bone forming 
 the third pit is hollow, and called the fossa siibscapularis 
 or venter (12) ; the spine, sjjina (13), begins from the 
 base, where it has a small smooth surface about an inch 
 and a half below the superior internal angle, it passes 
 outwards and upwards, and terminates in the acromion, 
 processus acromion (14), which is expanded over the top 
 of the glenoid cavity, and about an inch above it, forming 
 the point of the shoulder ; it is of a triangular figure, and 
 has an articular surface (15) on its inner and anterior 
 edge to join with the clavicle ; the third process is the 
 coracoid, processus coracoides (16), which originates by a 
 thick root from the fore and upper part of the neck of 
 the bone, and curves forwards and outwards before the 
 glenoid cavity ; the notches, incimrce, are, one in the 
 superior edge (17) at the root of the coracoid process, 
 and to its inner side for the passage of the suprascapular 
 artery, vein, and nerve ; and one between the root of the 
 glenoid cavity and the root of the acromion (18), through 
 which the superior dorsal artery and vein pass to the 
 fossa infraspinata. 
 
 Connection. By the articular surface on the acromion 
 V. ith the collar bone. 
 
 p 2 
 
36 A DESCRIPTION OF THE BONES. 
 
 The muscles attached to the scapula are sixteen, viz. 
 to the spine above, M. trapezius, and below, M. dehoides ; 
 to tlie base M. levator scapulae, rhomboideus minor & 
 major, & serratus magnus ; to the notch in the superior 
 costa, M. omo-hyoideus ; to the fossae, M. supraspina- 
 tus, infraspinatus &: subscapularis ; to the inferior 
 costa, M. teres minor & triceps extensor cubiti (its long 
 head) ; to the inferior angle, M. teres major ; and to 
 the coracoid process, M. coraco-brachialis, pectoralis 
 minor &: biceps flexor cubiti (its short head) ; the latter 
 also from the upper edge of the glenoid cavity (its long 
 head). 
 
 2. THE UPPER ARiM, Brachium, 
 Consists of a single bone. 
 
 THE BONE OF THE ARIM. Os Humeri. 
 
 Situation. On the side of the chest, forming the 
 upper arm ; attached to the scapula above, and to the 
 radius and ulna below. 
 
 Description, The os humeri, or upper arm, is 
 divided into the head, two tubercles, body, two condyles, 
 three articular surfaces, and two pits. 
 
 Tiie head, cajnit (1), which is hemispherical, is placed 
 at the upper and inner part of the bone, facing upwards, 
 inwards, and rather backwards, it is smooth to articulate 
 with the glenoid cavity of the scapula, and around its 
 edge are the marks produced by the attachment of the 
 capsular ligament ; on the outer and fore part are seen the 
 two tubercles, separated by a groove, sulcus bicipitalis 
 (2), for the tendon of the long head of the M. biceps, the 
 
A DESCRIPTION OF THE BONES. 
 
 37 
 
 anterior or lesser tubercle, tuhercuhnn mmiis (3), giving 
 insertion to the M. subscapularis, the external or greater 
 
 tubercle, tuber culinn ma- 
 jus (4), giving insertion 
 to the M. supraspina- 
 tus, infraspinatus & teres 
 minor ; immediately be- 
 low the head and tuber- 
 cles the bone is con- 
 tracted, and forms the 
 neck, cervix (5); the body, 
 corpus (6, G), appears as 
 if the upper part were 
 twisted outwards and 
 the lower inwards ; the 
 hole for tlie medullary 
 artery, foramen medul- 
 lare, is about one-third 
 of the bone downwards ; 
 extending from the fore 
 part of the greater tuber- 
 cle downwards is the 
 outer edge (7) of the bi- 
 cipital groove, to which 
 the M. pectoralis major 
 is attached, and from 
 the lesser tubercle the 
 inner edge (8) of the same groove, to which the M. 
 latissimus dorsi 8c teres major are attached ; one-third 
 down on the outside is a rough surface (9), to whicli the 
 M. deltoides & brachialis internus are attached ; at the 
 same distance from the head, and to the inner side of the 
 
38 A DESCRIPTION OF THE BONES. 
 
 bicipital groove another rough surface (10) for the attach- 
 ment of the M. coraco-brachialis & brachialis externus 
 (one of the heads of the M. triceps) : from the middle of 
 the bone on the outside extending downwards to the 
 outer condyle, is a line (11) giving origin to the I\I. supi- 
 nator radii longus & extensor carpi radialis longior, and 
 on the inside another line (12) passing to the inner con- 
 dyle ; between these two lines the M. brachialis internus 
 arises before, and the M. brachialis externus behind ; the 
 outer condyle, condylus externus (13), which is at the outer 
 side of the lower end of the bone, projects but little, it 
 gives origin to the M. anconeus, extensor carpi ulnaris, 
 extensor communis digitorum, extensor carpi radialis 
 brevior & supinator radii brevis ; the inner condyle, con- 
 dylus internus (14), at the inside of the lower end of the 
 bone, projects very much inwards, it gives origin to the 
 M. pronator radii teres, and all the long flexors of the 
 hand and fingers, except the M. flexor digitorum pro- 
 fundus ; the lowest part of the bone has two articular 
 surfaces upon it, that on the outside convex (15) from 
 before to behind, and from side to side, for the head of 
 the radius; and that on the inside convex (1(3) from be- 
 fore to behind, and concave from side to side, for the 
 sigmoid cavity of the ulna ; between this articular sur- 
 face and the inner condyle behind, is a groove, sulcus 
 ulnaris (17), for the ulnar nerve : above the articular 
 surfaces before, is a pit (18) for the coronoid process of 
 the ulna, and behind another (19) deeper for the olecra- 
 non of the ulna ; around the condyles there are ligamen- 
 tous marks. 
 
 Connection. With the scapula above, and with the 
 radius and ulna below. 
 
A DESCRIPTION OF THE BONES. 39 
 
 The muscles attached to the os humeri are twenty- 
 four ; viz. jNI. deltoides, supraspinatus, infraspinatus, 
 teres minor, subscapularis, pectorahs major, latissimus 
 dorsi &: teres major, coraco-brachialis, triceps extensor 
 cubiti, brachiahs internus, palmaris longus, flexor carpi 
 radialis, flexor carpi ulnaris, flexor digitorum subhmis 
 perforatus, flexor longus poUicis, pronator radii teres, 
 supinator radii longus & brevis, extensor carpi radialis 
 longior & brevior, extensor carpi ulnaris, extensor digi- 
 torum communis, & anconeus. 
 
 3. THE FORE ARM, Antihrachhm, 
 Consists of two bones, the ulna and radius. 
 
 THE CUBIT. Ulna (I). 
 
 Situation. On the inside of the fore arm, attached 
 above to the os humeri, on the outer side to the radius, 
 and below by means of an interarticular cartilage to the 
 OS cuneiforme. 
 
 Description. The ulna is divided into a body, ex- 
 tremities, four processes, and four articular surfaces. 
 
 The upper extremity is very large, scooped out ante- 
 riorly to form the greater sigmoid cavity, cavitas sigmoidea 
 major (1), which faces forwards, and is divided by a mid- 
 dle ridge (2), for the inner articular surface of the base 
 of the OS humeri, and bounded before by a projecting lip 
 called the coronoid process, 'processus coronoides (3) ; on 
 
40 
 
 A DESCRIPTION OF THE BONES. 
 
 the outer side, between the olecranon and the coronoid 
 process, is a concave articular surface for the head of 
 the radius, the lesser sigmoid cavity, 
 cavitas s'lgmoidca minor (4) ; below, and 
 before the coronoid process, is another 
 process called the tubercle, iuher (5) ; 
 the greater sigmoid cavity is bounded 
 behind and above by the olecranon, 
 lyroccssus olecranon (6), which forms the 
 projecting part of the elbow, gives 
 insertion to the M. triceps extensor 
 cubiti behind, and to the M. anconeus 
 on its outer edge ; it has a flat surface 
 on the posterior part covered only by 
 skin, which is strictly the place called 
 the elbow, or ancon (7) ; the body of 
 the bone, corpus (8), is strongly marked 
 by the attachment of muscles ; it is 
 rounded and smooth on the inner, and 
 ^vf^ sharp on the outer side, for the attach- 
 ^^£'1^ ment of the interosseous ligament; about 
 a third down is the hole for the medul- 
 lary artery ; the lower end of the bone is rounded, having 
 a rounded articular surface (9) on its outer side for the 
 base of the radius, and an irregular one (10) below for the 
 interarticular cartilage ; on the inside it is lengthened to 
 form the styloid process, j^^ocessus styliformis (ll), and on 
 the back is a slight groove (12) for the M. extensor 
 carpi ulnaris. 
 
 Connection. With the humerus above : with the radius 
 on the outside ; and by the interarticular cartilage with 
 the cuneiform bone below. 
 
A DESCRIPTION OF THE BONES. 
 
 41 
 
 The muscles attached to the ulna are fifteen ; viz. M. 
 brachiahs internus, triceps extensor cubiti & anconeus, 
 pronator radii teres, flexor carpi radiahs, flexor carpi 
 ulnaris, flexor digitorum communis sublimis & profun- 
 dus, supinator radii brevis, pronator quadratus, extensor 
 carpi ulnaris, extensor ossis metacarpi pollicis, extensor 
 primi internodii pollicis, extensor secundi internodii 
 pollicis &: indicator. 
 
 THE SMALL BONE OF THE ARM. Radius (II). 
 Situation. On the outside of the fore arm, attached 
 above to the os humeri, on the 
 inner side to the ulna, and below to 
 the OS scaphoides and lunare. 
 
 Description. The radius is said 
 to resemble the spoke of a wheel ; 
 it is divided into head, neck, body, 
 base, two processes, four articular 
 surfaces, and four grooves. 
 
 The head or upper part, caput (1), 
 is rounded, having a concave articular 
 surface at the top (2), to receive the 
 convex articular surface of the outer 
 condyle of the os humeri ; on the 
 side of the inner and anterior half of 
 the head is an articular surface (3), 
 by which it joins with the lesser sig- 
 moid cavity of the ulna ; immediately 
 below this the bone is contracted to 
 form its neck, cervix (4), bounded 
 below on the fore and inner part by 
 an obtuse process called the tubercle, tuher (5), into 
 
42 A DESCRIPTION OF THE BONES. 
 
 which tlie tendon of the M. biceps flexor cubiti is in- 
 serted; the body, corpus (6, 6), is rounded along its 
 outer edge (a), and sharp within (b), to give attachment 
 to the interosseous ligament : the lower end of the bone 
 is much expanded, forming the base, basis (7), which 
 has a triangular concave articular surface (8), with its 
 apex outwards for the scaphoid and lunar bones, some- 
 times divided by a ridge ; on the inside it has a concave 
 articular surface (9) for the lower extremity of the ulna ; 
 on the outer edge it is extended to form the styloid 
 process, processus styliformis (10), and has a groove (11), 
 through which pass the tendons of the M. extensor ossis 
 metacarpi & extensor primi internodii pollicis, and on 
 the back three other grooves, the largest of which is the 
 outermost (12), for the tendons of the M. extensor carpi 
 radialis longior & brevior ; next to it is a small one (13), 
 for that of the M. extensor secundi internodii pollicis, 
 and the innermost (14), nearest the ulna gives passage 
 for those of the M. indicator & extensor disitorum 
 communis. 
 
 Connection. With the humerus above ; with the ulna 
 on the inside ; and with the scaphoid and lunar bones 
 below. 
 
 The muscles attached to the radius are eight : viz. the 
 M. supinator radii longus & brevis, pronator teres, & 
 quadratus, biceps flexor cubiti, flexor digitorum commu- 
 nis sublimis, flexor pollicis longus, & extensor ossis 
 metacarpi pollicis. 
 
 4. THE HAND, Manns, 
 
 Consists of the carpus, metacarpus and phalanges ; 
 of these, part of the carpus (a) with the radius form the 
 
A DESCRIPTION OF THE BONES. 
 
 43 
 
 wrist joint ; the metacarpus (b) forms the palm of the 
 hand ; and the phalanges (c) the fingers. 
 
 THE CARPAL BONES. Carpus. 
 
 Situation, Between the fore arm and hand. 
 
 Description. They consist of eight bones forming an 
 arch, supported by ligament, the concavity of which 
 is placed before, and the convexity behind. These eight 
 bones are arranged in two rows, four in each ; they are, 
 in the first row, on the outside the os scaphoides (i), on 
 
 IV Upper Surf ace 
 
 Lower Surface. IV 
 
 its inner side the os lunare (ii), next it the os cunei- 
 forme (in), and on the front of that bone the os pisi- 
 
44 
 
 A DESCRIPTION OF THE BONES. 
 
 forme (iv) : in tlie second row, on the outside is the os 
 trapezium (v), next to it, the os trapezoides (vi), to its 
 
 V VI VII Vlll VIII VU VI V 
 
 Loicer Surface, i 
 
 inner side, the os magnum (vii), and next to that the os 
 unciforme (viii). Of these bones the first row is arti- 
 culated above vvath the radius, and the interarticular car- 
 tilage at the extremity of the ulna, and below with the 
 second row ; the second row articulates above with the 
 first row, and below with the bases of the metacarpal 
 bones.* 
 
 THE SCAPHOID BONE. Os Scapho'ides (I). 
 
 Description. The scaphoid bone somewhat resembles 
 a boat in shape ; it has four articular surfaces, one above (1 ), 
 the largest, is convex, and of a triangu- 
 lar shape, with its apex outwards for the 
 base of the radius ; one on the back and 
 under part also convex (2), for the os 
 trapezium and os trapezoides ; one on 
 the inner and upper part small and flat (3), for the lunar 
 bone; and one below it and on the inside concave (4), to 
 form part of the socket for the head of the os magnum : 
 the rest of the bone not occupied by articular surfaces 
 is strongly marked by ligament. 
 
 * The surfaces figured on the upper and lower surfaces of these rows 
 of the carpus are referred to in the description of the single bones to save 
 repetition. 
 
A DESCRIPTION OF THE BOXES. 45 
 
 Connection. Above to the radius, below to the tra- 
 pezium & trapezoid, on the inner side to the lunar, and 
 below it to the large bone. 
 
 There are no muscles attached to this bone. 
 
 THE LUNx\R BONE, Os Lunare (II). 
 
 Description. The lunar bone is said to resemble a 
 half moon, its convexity being placed upwards ; it is 
 largest on its fore part, and projects into the carpal arch ; 
 it has four articular surfaces; one above convex (1), for 
 A,^' _— :r5) ^^^^ radius; one below concave (2), which 
 li '^\ ,-;,? with that of the scaphoid bone, forms the 
 ■"^^^""^ Vl!7 cup for the head of the os magnum ; one 
 on the outside flat (3), for the scaphoid bone; and one 
 on the inside also flat (4), for the cuneiform bone. 
 
 Connection. With the radius above, and the laro-e 
 bone below, with the scaphoid on the outer, and the 
 cuneiform on the inner side. 
 
 No muscles attached to this bone. 
 
 THE CUNEIFORM BONE. Os Cuneiforme (III). 
 
 Description. The cuneiform bone is said to resemble 
 a wedge, the base of which faces outwards, and the apex 
 inwards ; it has four articular surfaces ; a small one on 
 
 its upper and outer edge 
 J \ /<^^^ ^'T^s^ /KV E (1 )j for the interarticular 
 
 cartilage, which is at- 
 tached to it ; another 
 on the outside (2), for the lunar bone ; one below slightly 
 and irregularly concave (3), for the unciform bone ; and 
 a flat one on its fore part (4), for the os pisiforme. 
 
46 A DESCRIPTION OF THE BONES. 
 
 Connection. Above with the interarticular cartilage 
 of the uhia, below with the unciform bone, on the outside 
 with the lunar, and before with the pisiform bone. 
 
 No muscles attached to this bone. 
 
 THE PISIFORM BONE. Os Pisiforme (IV). 
 Description. This bone is named from its resemblance 
 to a large pea; it is rounded before (1), and has a flat 
 articular surface behind (2). 
 
 Connection. With the front of the cunei- 
 form bone. 
 
 The muscles attached to it are three ; viz. 
 the M. flexor carpi ulnaris, abductor minimi digitorum, 
 & palmaris brevis. 
 
 THE TRAPEZIUM. Os Trapezium (V). 
 Description. Said to resemble the mathematical 
 figure of that name, but of an irregular form ; it is re- 
 
 4-!f^^ markable for a deep groove (1), on its 
 ]» '1 fore part, through which the tendon of 
 ^^\'M the M. flexor carpi radialis passes ; it 
 y^^ has four articular surfaces ; one concave 
 above (2), for the scaphoid bone ; one on the inside (3), for 
 the trapezoid bone ; a large one on the outside (4), con- 
 cave from above downwards, and convex from before to 
 behind, for the metacarpal bone of the thumb ; and a 
 small flat one below (5), for part of the metacarpal bone 
 of the fore finger, between that for the metacarpal bone 
 of the thumb and that for the trapezoid bone. 
 
 Connection. Above to the scaphoid, on the outside 
 to the metacarpal bone of the thumb, on the inside to the 
 trapezoid, and below to the metacarpal bone of the fore 
 finjrer. 
 
A DESCRIPTION OF THE BONES. 47 
 
 The muscles attached to it are four ; viz., M. flexor 
 ossis metacarpi polHcis, abductor pollicis, abductor indicis 
 & extensor ossis metacarpi poliicis. 
 
 THE TRAPEZOID BONE. Os Trapezoides (VI). 
 
 Description. The trapezoid bone, hke the preceding, 
 is also said to resemble the mathematical figure ; it is, 
 f^ C^^^ however, of a very irregular shape, 
 ■'( f^ ''^ being broadest and smoothest be- 
 hind (1), with its lower edge rounded: 
 it has four articular surfaces, one above (2), for the 
 scaphoid ; one on the outside (3), for the os trapezium ; 
 one on the inside (4), for the os magnum ; and one be- 
 low (5), for the metacarpal bone of the fore finger. 
 
 Connection. Above wuth the scaphoid, below with 
 the metacarpal bone of the fore finger, on the outside 
 with the OS trapezium, and on the inside with the os 
 magnum. 
 
 The only muscle attached to this bone is the M. flexor 
 brevis pollicis. 
 
 THE LARGE BONE. Os Magnum (VII). 
 
 Description. This is the largest bone of the carpus, 
 from whence it derives its name ; it has six articular sur- 
 faces ; it is sometimes called os capitatum, on account of 
 
 the head or large hemi- 
 spherical articular surface 
 |'S|^ J W^^ ' '^--^^ (1)' at the upper part, 
 >^f " which forms a ball to be 
 
 received into a socket formed in the first row of the carpal 
 bones by the scaphoid and lunar bones, which tends much 
 
48 
 
 A DESCRIPTION OF THE BONES. 
 
 to Strengthen the junction of the parts of the carpus to 
 each other ; on the outside, the large bone has an arti- 
 cular surface for the trapezoid (2), and on the inner (3), 
 for the unciform bone ; below, it has an irregularly con- 
 cave surface (4), for the metacarpal bone of the middle 
 finger, the outer edge of which (5) is pared off, as it were, 
 to articulate it with a small portion of the metacarpal 
 bone of the fore finger ; and a similar but much smaller 
 articular surface is found on the posterior and inner 
 point (6), for the metacarpal bone of the ring finger. 
 
 Coimect'ion. Above with the scaphoid and lunar, on 
 the outside with the trapezoid, and on the inner side with 
 the unciform bone, below in the middle with the meta- 
 carpal bone of the middle, on the outside with that of the 
 fore, and on the inside with that of the ring finger. 
 
 The only muscle attached to this bone is the M. flexor 
 brevis pollicis. 
 
 THE UNCIFORM BONE. Os Unciforme (VIII). 
 
 Descriiition. The unciform bone has a remarkable 
 hook-like process (1), on its fore and inner edge, which 
 
 curves outwards towards the root 
 of the thumb ; it has four arti- 
 cular surfaces ; one large above 
 and to the inner side (2) for the 
 cuneiform ; one on the outside (3), for the os magnum ; 
 and two below divided by a ridge («), the outer smaller 
 one (4), for part of the metacarpal bone of the ring finger, 
 and the other (5), for the metacarpal bone of the little 
 finder. 
 
A DESCRIPTIOX OF THE BONES. 
 
 49 
 
 Connection. Above with the cuneiform, on the out- 
 side with the large bone, and below with the metacarpal 
 bones of the ring and little fingers. 
 
 The muscles attached to this bone are three ; viz. the 
 M. flexor brevis pollicis, flexor proprius. & adductor 
 minimi digiti. 
 
 THE METACARPAL BONES. Ossa Mctacarpi. (B.) 
 
 Situation. Below the carpus and above the fingers, 
 
 forming the back and palm of tlie hand. 
 
 Description. Of tlie metacarpal bones there are five, 
 
 each of which is divided into its upper part, or basis (a ); 
 
 middle or body, corjnis (b); andlower part or head, caput (c ), 
 
 which forms ^the knuckle, and projects when the fingers 
 
 are bent. Upon the 
 bases are articular sur- 
 faces for the carpal 
 bones ; the bodies be- 
 hind are sharp above 
 and expanded below 
 towards the knuckles,* 
 before they are ex- 
 panded above and 
 sharp below for the 
 purpose of giving room 
 for the M. interossei ; 
 the heads of all except 
 that of tiie thumb, are 
 convex from before to 
 
 behind and from side to side, having large articular sur- 
 
 * See page 43. 
 E 
 
.50 A DESCRIPTION 01' THE BONES. 
 
 faces for the first row of the phalanges of the fingers ; 
 and immediately above the head is a groove for the 
 attachment of the capsular ligament. They differ much 
 from each other, particularly that 
 
 Of the Thumb (i), which very much resembles the 
 first phalanx of the fingers : it is the shortest of all the 
 metacarpal bones, and placed obliquely on the carpus, in- 
 stead of perpendicularly like the other metacarpal bones ; 
 it is of the same breadth throughout, smooth behind, 
 rounded from side to side before, and forming a sharp 
 edge on either side : the articular surface on its base (1) 
 is much expanded ; it is convex laterally, and concave 
 from before to behind, the anterior lip being much pro- 
 duced ; its head is slightly convex from before to behind, 
 but flat laterally. 
 
 Connection. With the trapezium above. 
 
 Of the First Finger (ii). The basis of this bone 
 has three articular surfaces divided by two edges, the 
 middle and larger for the os trapezoides (l) ; the outer 
 and smaller for the os trapezium (2) ; and the inner for 
 the OS magnum (3) ; immediately below the articular 
 surface for the os magnum, is a plane surface on the side 
 for the metacarpal bone of the second finger. 
 
 Connection. With the trapezium, trapezoid, and large 
 bone above, and with the metacarpal bone of the second 
 finger on the inside. 
 
 Of the Second Finger (in). The basis of this bone 
 has an articular surface in the middle for the os mag- 
 num (1) ; one on the outer side of the base concave (2) 
 for the base of the metacarpal bone of the first finger, 
 and another on the inside for that of the third finger. 
 
 Connection. With the os magnum above, with the 
 
A DESCRIPTION OF THE BONES. 51 
 
 metacarpal bone of the first finger on the outside, and of 
 the third finger on the inside. 
 
 Of the Third Finger (iv). The basis of this has 
 two articular surfaces, a very small one at the upper and 
 outer part (1) for the os magnum, and a large one on 
 the upper and inner part (2) for the os unciforme; on 
 each side of the base are articular surfaces for the meta- 
 carpal bones of the second and fourth fingers. 
 
 Connection, Above with the large and unciform 
 bone ; on the outside, with the metacarpal bone of the 
 second, and on the inside with that of the fourth finger. 
 
 Of the Fourth Finder (v). The base has an articu- 
 lar surface above (1) for the os unciforme, and on the 
 outside another for the metacarpal bone of the third 
 finger. 
 
 Connection. With the os unciforme above, and the 
 metacarpal bone of the third finger on the outside. 
 
 The muscles attached to the metacarpal bones are fif- 
 teen ; viz. M. interossei (seven), common to all except 
 that of the thumb ; to that of the thumb before, M. flexor 
 brevis & flexor ossis metacarpi pollicis, & abductor indicis, 
 and 6eAmrf, extensor ossis metacarpi pollicis; to that of the 
 fore finger before, IM. flexor carpi radialis, and behind, M. 
 extensor carpi radialis longior ; to that of the middle fin- 
 ger, M. extensor carpi radialis brevior, and to that of the 
 little finger, M. extensor carpi ulnaris. 
 
 THE FINGERS. Phalanges Digitorum. (C). 
 
 The thumb and fingers of each hand consist of four- 
 teen pieces or phalanges, of these twelve belong to the 
 fingers, and are disposed in three rows, those of the 
 
O'Z 
 
 A DESCRIPTION OF THE BONES. 
 
 middle finger being longest, and of the little finger short- 
 
 Front. 
 
 est ; whilst the thumb 
 has but two, its middle 
 phalanx being deficient, 
 but they are stronger 
 than those of the fingers. 
 The phalanges consist of 
 base (1), body (2), and 
 head (3), ancl they taper 
 from the base or upper 
 part to the head, the in- 
 termediate part or body 
 being; rounded behind.* 
 and flat before, with two projecting lateral edges to give 
 attachment to the sheaths of the tendons. 
 
 In the First Row {a) the base (1) is concave from before 
 to behind, and from side to side, in which direction it is 
 longest ; the head (3) has a pulley-like articulation upon it, 
 concave laterally, broadest in front, and convex from be- 
 fore to behind. 
 
 In the Second Row (5), which is wanting in the thumb, 
 the base (l) is concave laterally, and deepened before and 
 behind in the middle by a lip, between which a ridge ex- 
 tends, dividing it into two smaller concavities : the body (2) 
 and head (3) are like those of the first row, but the body 
 is shorter. 
 
 In the Third Row (c) the phalanges become very ta- 
 per, their bases (l) are like those of the second, but their 
 points (3) are expanded into thin rough surfaces, which are 
 rounded at the tip and give attachment to the nails. 
 
 * See page 43. 
 
A DESCRIPTION OF THE BONES. 53 
 
 The muscles attached to the phalanges are twenty- 
 one ; viz., before, M. flexor brevis digitorum sublimis, & 
 profundus, flexor longus 8: brevis, & adductor & abduc- 
 tor pollicis, flexor proprius & adductor minimi digiti, 
 lumbricales (four), & interossei (seven) ; behind, M. 
 extensor digitorum communis & indicator. 
 
 SESAMOID BONES. Ossa Sessamoidea. 
 
 Of these there are usually two at the root of the first 
 
 ^ phalanx of the thumb ; they are small bones, round 
 
 ^ before and flat behind ; they give attachment to the 
 
 U M. flexor brevis pollicis manus ; sometmies there 
 
 are also some to the little finger. 
 
 CHAP IV. 
 
 Of the Lower Extremity. 
 
 The lower extremity consists of the thigh, leg, and 
 FOOT, which are connected by the head of the thigh bone 
 with the acetabulum. 
 
 1. THE THIGH, Femur, 
 Consisting of a single bone. 
 
 THE THIGH BONE. Os Femoris. 
 
 Situation. In the thigh between the trunk above and 
 the leg below. 
 
54 
 
 A DESCRIPTION OF THE BONES. 
 
 Description. The os femoris is tlie largest bone in 
 the body ; it consists of a liead, neck, and trochanters, 
 
 or upper part : 
 a body or mid- 
 dle ; and con- 
 dyles, or lower 
 part. 
 
 The head, 
 caput (1), is si- 
 tuated at the 
 upper and in- 
 ner part of the 
 bone, forming 
 the greater part 
 of a sphere, 
 and presenting 
 a large articular 
 surface which 
 faces upwards 
 and inwards? 
 and has a rough 
 hole (2) in it, to 
 w^hich is attach- 
 ed the round li- 
 gament; extend- 
 in o- outwards 
 and downwards 
 to join with the 
 upper part of 
 the body is the neck, cervix (3), which is broader below 
 than above and flattest behind and before ; a rough oblique 
 line marks the extent of the neck and the attachment of the 
 
A DESCRIPTION OF THE BONES. 55 
 
 capsular ligament in front (4) ; the upper and outer part of 
 the body projects above the neck, forming the greater 
 trochanter, trochanter major (5), which is smooth on the 
 outer and back part where the M. gluteus maximus 
 passes over it ; its upper part gives attachment to the M, 
 gluteus medius & minimus, and has, on the inside, a deep 
 pit, fossa trochanterica (6), to give insertion to some of the 
 abductor muscles : about two inches below it, on the inner 
 and back part of the bone, is a strong rounded projecting 
 process, the lesser trochanter, trochanter minor (7), to 
 which the M. psoas magnus & iliacus are attached ; a 
 curved line, linea quadrata (8), extending from one trochan- 
 ter to the other, gives attachment to the M. quadratus 
 femoris, and marks the termination of the neck and the 
 attachment of the capsular ligament posteriorly : the body, 
 corpus (9), is arched in front and slightly concave behind ; it 
 is smooth and slightly rounded before, but sharp in the 
 middle behind, forming the rough line, linea aspera (10), 
 which occupies the middle third of the bone, and divides 
 above and below into two lines, the two upper (c, c) pass 
 one into each trochanter, and the two lower {d, d) one 
 into each condyle, having between them a flat triangular 
 space, strictly called the Ham (11 ), in which the popliteal 
 artery, vein, and nerve lay ; the lower end of the bone 
 becomes much expanded to form the condyles, con- 
 dyli (12, 13), of which the inner (13) is considerably the 
 larger and longer ; upon the condyles are four articu- 
 lar surfaces, the two ttpjoer (14, 15) on the fore part for 
 the patella, of which that on the outer condyle (15) is the 
 larger, and separated from each other by a slight depres- 
 sion, and the two lower (16, 10) for the head of the tibia, 
 extending very far backwards and upwards, and separated 
 
.■)() A DESCRIPTION OF THE BONES. 
 
 by a very deep pit (17), into which the crucial ligaments 
 are inserted ; these articular surfaces are broadest below 
 and narrowest behind and above ; on the inside of the 
 inner condyle, and above its articular surface is a projec- 
 tion (18) more or less distinct, to which the M. adductor 
 magnus femoris is attached. The medullary artery enters 
 about the middle of the back of the bone. 
 
 Connection. By means of the head, with the aceta- 
 bulum of the OS innominatum above, and by the condyles 
 below, with the tibia, and before, with the patella. 
 
 The muscles attached to this bone are nineteen : viz. 
 to tlie trochanter major, M. gluteus medius & minimus ; 
 to the trochanter minor, M. psoas magnus & iliacus ; to 
 the linea qiiadrata, M. quadratus ; to the fossa trochan- 
 terica, M. obturator internus & externus, gemini and 
 pyriformis ; to the Unea aspera, M. gluteus maximus, 
 pectineus, & triceps femoris, vasti & biceps flexor cruris ; 
 to the condyli, M. gastrocnemius externus, plantaris & 
 popliteus; to the fore 2:)art of the body, M. crureus : the 
 M. sartorius, gracilis, &: tensor vaginas femoris, are upon 
 the OS femoris, but not attached to it. 
 
 2. THE LEG. Cms, 
 
 The leg is composed of three bones, the patella, 
 TIBIA, and FIBULA, which in their disposition are analogous 
 to the bones of the fore arm, but with these two dif- 
 ferences : — 1st, that the patella which corresponds to 
 the olechranon of the ulna in its use as a protection to 
 the joint, and as increasing the length of the lever on 
 which the great extensor muscle of the limb acts, is a 
 separate and moveable bone, instead of formino-, like 
 
A DESCRIPTION OF THE BONES 
 
 57 
 
 the olechranon, part of the bone itself; and, 2cl]y, that 
 there is but the least possible motion between the two 
 large bones, instead of the rotation of one bone upon 
 the other, as in the fore arm. 
 
 J2 
 
 THE KNEE CAP. Patella (I). 
 
 Situation. On the front of the knee and protecting 
 the joint : it may be considered to bear the same 
 relation to the tibia, which the olecranon does to the 
 
 ulna. 
 
 Description. The patella is of a heart shape, with 
 the base, basis (1), above, and the 
 point, ajoex (2), below, the sides, 
 margines (3), are between the base 
 and point ; it is convex laterally 
 and from above downwards, and rough in front in 
 consequence of the attachment of the tendon of the 
 M. rectus, and the ligament of the patella ; it has two 
 articular surfaces (4, 5) behind, slightly concave, and 
 divided by a middle perpendicular projecting ridge (6), 
 the outer (4) of them being the larger. 
 
 Connection. With the condyles of the os femoris 
 behind. 
 
 The muscles attached to the patella are four; viz. 
 to the basis, M. rectus and crureus, and to the sides^ 
 M. vasti. 
 
58 
 
 A DESCRIPTION OF THE BONES. 
 
 THE SHIN BONE. Tibia (II). 
 
 Situation. On the inside of the leg. 
 
 Description. The tibia is said to resemble an ancient 
 flute in shape : it consists of a head or upper part, body 
 
 or middle, base or lower 
 part, two processes and six 
 articular surfaces. 
 
 The head, caput (1), is 
 much expanded, and of an 
 oval form, with its long axis 
 from side to side ; on the 
 top it has two semicircular 
 articular surfaces (2, 3) for 
 the condyles of the os fe- 
 moris, of which the inner 
 (3) is the larger ; these are 
 slightly concave, and have 
 their diameters towards 
 each other, separated by a 
 middle ridge (4), having 
 one pit before (5) and ano- 
 ther behind it (6), to which 
 the crucial ligaments are 
 attached ; on the posterior 
 under and outer part of the 
 head is a small flat arti- 
 cular surface (7) for the 
 head of the fibula ; about an 
 inch below the head on the 
 fore part is the tubercle, 
 tubcj' (8), which gives at- 
 tachment to the ligaments of the patella and some mus- 
 
A DESCRIPTION OF THE BONES 59 
 
 cles ; the body, corpus (9, 9) is of a prismatic form, the 
 base (10) of which is behind, and the apex before, which 
 latter presents a sharp ridge extending down to the inside 
 of the base, and called spine or shin, sjnna (11); the inside 
 of the body is very smooth and covered only by skin, the 
 outside slightly hollowed for the lodgement of muscles, 
 and the posterior irregularly flat and marked by an 
 oblique line, Unea implHea (12), which extends from the 
 articular surface for the fibula across to the inner edge 
 of the bone, about a third downwards, and marks the at- 
 tachment of the M. popliteus and gastrocnemius internus. 
 The lower part of the bone is expanded to form the base, 
 basis (13), which has an articular surface upon it (14), 
 concave from before to behind for the top of the astra- 
 galus ; on the inside the base is lengthened by a strong 
 process, the inner ankle, malleolus internus (15) which is 
 marked on the under back part by a slight groove (IG) 
 for the passage of the tendon of the M. tibialis posticus, 
 and has a flat articular surface on the outside (17) for the 
 inside of the astragalus ; on the outside of the base is an 
 irregular articular surface for the fibula (18). The hole 
 for the medullary artery is in the middle and back part. 
 
 Connection. Above with the condyles of . the os 
 femoris, below and to the inner side with the astragalus, 
 and on the outside to the fibula. 
 
 The muscles attached to this bone are ten ; viz. below 
 the tubercle, M. sartorius, gracilis, semitendinosus ; to 
 the back of the head, M. semimembranosus ; to the 
 back of the head and body, M. popliteus, gastrocnemius 
 internus, tibialis posticus, flexor longus digitorum pedis ; 
 and to the fore part of the head and body, M. tibialis 
 anticus & extensor longus digitorum pedis. 
 
60 
 
 A DESCRIPTION OF THE BONES. 
 
 THE SPLINT BONE. Fibula (III). 
 
 Situation. On the outside of the leg, and forming a 
 
 splint or support to the tibia. 
 
 Descrijotion. The fibula is of a very irregular shape, 
 
 and composed of a head, body, base, two processes, and 
 three articular surfaces. 
 
 The head, caput (1), or upper extremity, 
 is large and irregular, it has a smooth 
 articular surface (2) on its inner side facing 
 upwards and inwards to join it with the ti- 
 bia, and on the upper and outer part a little 
 projecting process, processus bicipitalis 
 (3), for the attachment of the M. biceps 
 flexor cruris : the body, corptus (4, 4), con- 
 sists of several ridges and depressions for 
 the origin and lodgement of muscles ; it 
 becomes larger at the base, basis (5), which 
 is smooth in front, and covered only by 
 skin ; on its inner side is an irregular 
 articular surface (6) to join it with the 
 outside of the base of the tibia ; below 
 the base is lengthened to form the outer 
 ankle, malleolus externus (7), on the inside 
 of which is an oblique articular surface 
 (8) facing downwards and inwards for the 
 outside of the astragalus ; the extreme 
 *^|I^ outer point gives attachment to Ugaments, 
 and the posterior part (9) is grooved for 
 the tendons of the M. peronei. The 
 
 medullary artery enters in the middle of the posterior 
 
 part of the bone. 
 
A DESCRIPTION OF THE BONES. 
 
 61 
 
 Connection, On its inside above to the tibia, and 
 below to that bone and the astragalus. 
 
 The muscles attached to this bone are eight : viz. to 
 the processus biclpitaUs, M. biceps flexor cruris ; to the 
 fore part of the body, M. extensor longus digitorum 
 & extensor proprius pollicis pedis ; on the outside, the 
 M. peroneus longus & brevis ; and behind, the M. 
 gastrocnemius internus, tibialis posticus, & flexor 
 longus pollicis pedis. 
 
 3. THE FOOT, Pes, 
 Consists of the tarsus, metatarsus, and toes. 
 
 THE TARSAL BONES, Tarsus (A), 
 
 Like the carpus, form a kind of arch, under which 
 
 tendons, vessels, and nerves 
 pass into the sole of the foot. 
 It consists of seven bones : 
 the astragalus, os calcis, and os 
 naviculare, form the first row ; 
 and the three ossa cuneiformia 
 
 and OS cuboides, compose the second row and support 
 
 the metatarsus.* 
 
 * Some of the articular surfaces are seen more distinctly when the 
 bones are connected, and therefore are numbered here. 
 
62 
 
 A DESCRIPTION OF THE BONES. 
 
 THE ASTRAGALUS. Astragalus (I). 
 
 Situation. At the upper and back part of the foot, 
 and connecting it with the leg. 
 
 Description. Said to resemble an ancient die ; it has 
 six articular surfaces ; it is convex above from behind to 
 before, forming its largest articular 
 surface (1) for the base of the tibia ; on 
 the inside it has a small articular sur- 
 face (2) nearly flat for the inner malle- 
 olus ; and on the outside it has a large 
 articular surface (3) concave from above 
 downwards and pointed below, for the 
 outer malleolus : the fore part of the 
 bone is rounded, forming the head (4), 
 which is smooth, to articulate it with the os naviculare : 
 the under part of the bone has two articular surfaces (5, 6) 
 for the OS calcis, separated by a deep groove (a), the 
 posterior concave (5) from within to without, and the 
 anterior slightly convex (6) ; those parts of the bone not 
 occupied by articular surfaces are marked by ligament. 
 
 Connection. By its upper articular surface with the 
 base of the tibia, on the inner side with the inner malle- 
 olus, on the outer with the outer malleolus ; below with 
 the OS calcis, and before with the os naviculare. 
 
 The only muscle attached to this bone is M. tibialis 
 posticus. 
 
A DESCRIPTION OF THE BONES. 
 
 6S 
 
 THE HEEL BONE. Os Calcis (H). 
 
 Situation. At the back, outer, and under part of the 
 foot, projectmg backwards to form the heel. 
 
 Description. The os calcis 
 is the largest bone of the foot ; it 
 is of an irregular figure ; it has 
 three articular surfaces, is flat 
 on the outside and concave on 
 the inside ; it is much lengthened 
 behind to form the heel, or tuberosity, tuher (1) ; on the 
 upper and fore part where the bone appears concave, are 
 two articular surfaces for the astragalus, the 
 posterior convex (2) and the anterior concave 
 (3), the inner edges of which project much 
 inwards, and form, with the inside of the tube- 
 rosity, a deep cavity, the sinuosity (4) through 
 which the flexor tendons pass into the sole of the foot ; 
 at the fore and outer part of the bone is an irregular con- 
 cave articular surface for the os cuboides (5). 
 
 Connection. By the two superior articular surfaces 
 with the astragalus, and by the anterior with the os cu- 
 boides. 
 
 The muscles attached to the os calcis are ten : viz. to 
 the upjoerpart, M. extensor brevis digitorum pedis ; to the 
 under part, M. abductor, flexor brevis & adductor polli- 
 cis pedis, flexor brevis & flexor digitorum accessorius, 
 & abductor minimi digiti ; the back part, M. gastroc- 
 nemius externus & internus, & plantaris. 
 
64< A DESCRIPTION OF THE BONES. 
 
 NAVICULAR BONE. Os Naviculare (III). 
 
 Situation. On the inner and upper part of the foot 
 before the astragalus. 
 
 Description. In shape resembles a boat, broad later- 
 J.^-^ ^ ally, narrow from before to 
 behind ; it has three articular 
 2. - surfaces, one behind deep and 
 concave (1) for the astragalus; another before convex 
 (2), divided by two ridges (3, 4) for the three ossa cunei- 
 formia ; and on the outer edge of the articular surface for 
 the outer cuneiform bone, a small articular surface (5) 
 for the OS cuboides ; on the inner side of the bone is a 
 strong projecting rounded process (6). 
 
 Connection. Behind with the astragalus, before with 
 the ossa cuneiformia, and on the outer edge with the os 
 cuboides. 
 
 The only muscle attached to this bone is, to its under 
 part, M. tibialis posticus. 
 
 CUNEIFORM BONES. 0^5^ Cuneiformia (IV. V. VI.) 
 
 Situation. On the inner and upper part of the foot ; 
 they are three in number, and are called from their posi- 
 tion, inner, middle, and outer cuneiform bones. 
 
 Description. The inner cuneiform bone (iv) is the 
 largest of the three, it is of an irregular prismatic shape, 
 its base placed below and the apex above ; it has four 
 
 articular surfaces, one behind 
 
 ^k I LsmmiiftttBiil / i^^ftilil/' concave (1) to form part of the 
 
 articulation for the navicular 
 bone; it has a plain articular 
 surface before (2) for the me- 
 tatarsal bone of the oreat toe ; its inner face is slightlv 
 
A DESCRIPTION OF THE BONES. Q5 
 
 convex, and has a smooth surface on its under and fore 
 part (3), to which the M. tibialis anticus and peroneus 
 longus are inserted ; its outer face is irregularly con- 
 cave, and has on its upper edge an irregular flat articular 
 surface (4) for the middle cuneiform bone, and a smaller 
 surface before it (5), for the inside of the metatarsal bone 
 of the second toe ; its under surface and the other parts 
 not smooth for articulation, are strongly marked by liga- 
 ment. 
 
 The middle cuneiform bone (v), wliich is of a prismatic 
 shape and the smallest of the three, has its base above 
 shghtly convex laterally : it has four articular surfaces ; 
 r^^ one behind, concave (1) for the navicular ; 
 T^T 1 one before, flat (2) for the base of the 
 -. a,J second metatarsal bone ; one on the inside, 
 nearly flat (3) for the inner cuneiform ; and one on the 
 outer and posterior part, slightly concave (4) for the 
 outer cuneiform bone. 
 
 The outer cuneiform bone, in shape resembling the 
 preceding and having its base upwards, has five articular 
 surfaces, one concave behind (1) for the 
 fi navicular; two before, the inner (2) for 
 the third metatarsal, and a very small 
 one on the outer corner (3) for part of the fourth meta- 
 tarsal ; two on the inside, the posterior (4) of which is for 
 the middle cuneiform, and the anterior (5) for the second 
 metatarsal ; and a large one on the outside (6) for the 
 cuboid bone. 
 
 Connection. The three cuneiform bones form a cup* 
 behind, into which is received the rounded articular sur- 
 face of the navicular bone ; before they join with the 
 
 * See page 62. 
 F 
 
(yG A DESCRIPTION OF THE BONES. 
 
 three larger metatarsal bones ; and in consequence of the 
 shortness of the middle cuneiform bone, a kind of mortise* 
 is formed by the inner and outer, in which the second 
 metatarsal bone is received like a tenon ; the middle cu- 
 neiform bone articulates on the inside with the inner, and 
 on the outside with the outer cuneiform bones ; and the 
 outer cuneiform joins by its outer surface with the cuboid 
 and with the fourth metatarsal bone. 
 
 The muscles attached to these bones are five ; viz. to 
 the inner, M. tibialis anticus & peroneus longus ; to the 
 outer, M. flexor brevis & adductor pollicis pedis ; and to 
 all three hones, M. tibialis posticus. 
 
 CUBOID BONE. Os Cuhoides. 
 
 Situation. On the outer part of the foot, immediately 
 before the os calcis. 
 
 Description. Of an irregular cuboidal form, its outer 
 edge being the shortest : it has three articular surfaces, the 
 largest of which is behind and concave 
 (1) for the OS calcis ; the anterior (2, 3) 
 slightly concave and divided by a middle 
 perpendicular ridge (4) into two for the 
 fourth (2) and fifth (3) metatarsal bones ; 
 and the smallest on the inside (5, 6) di- 
 vided by a ridge (7) into two unequal 
 portions, of which the smaller and poste- 
 rior (5) is for the outer and under edge of the navicular, 
 and the larger anterior (6) for the outer side of the outer 
 cuneiform bone : above, the bone is convex ; and below, 
 it has a deep groove (8) through which the tendon of the 
 
 * See page 62, 
 
A DESCRIPTION OF THE BONES. 
 
 67 
 
 M. peroneus longus plays ; the ridge, which bounds this 
 behind, terminates externally in a protuberance (9) the pos- 
 terior part of which marks its junction with the os calcis. 
 
 Connection. With the fore part of the os calcis be- 
 hind, with the two small metatarsal bones before, and on 
 the inside behind with the navicular, and before with the 
 outer cuneiform bone. 
 
 The muscles attached to this bone are two ; viz. on its 
 under surface, M. flexor brevis minimi digiti & adductor 
 poUicis pedis. 
 
 Bttses 
 
 THE METATARSAL BONES. Metatarsus. (B.) 
 
 Situation. Between the tarsus and toes. 
 
 Description. The metatarsus consists of five bones,* 
 
 of which the first, or that 
 of the great toe, is the 
 shortest and largest, and 
 that of the second the 
 longest. Like the meta- 
 carpus they have bases 
 (a), the broadest and 
 hindmost part, all which 
 have flat articular sur- 
 faces to join them with 
 the tarsus ; and heads, 
 (c) or anterior rounded 
 articular surfaces for the 
 phalanges ; the middle 
 part is the body, (b) 
 which is sharp above and 
 broad beneath. 
 
 * See page 61. 
 
 L'nder Surface. 
 
 F 'J 
 
(38 A DESCRIPTION OF THE BONES. 
 
 The first (i) has an articular surface on its base (1) for 
 the inner cuneiform bone, and one on the outside for the 
 second metatarsal. 
 
 The second (ii) has on its base an articular surface for 
 the middle cuneiform (1), two on the inner side, the hind- 
 most (2) for the inner cuneiform, the foremost for the first 
 metatarsal ; and two on the outside, both of which receive 
 part of the outer cuneiform (3) and the third metatarsal. 
 
 The third (in) has one on its base (l) for the outer 
 cuneiform, two on the inside for the second metatar- 
 sal, and a large one on the outside for the fourth me- 
 tatarsal. 
 
 The fourth (iv) has one on its base (1) for the cu- 
 boid, two on its inside, the hind one (2) for the outer 
 cuneiform, and the other for the third metatarsal, and 
 one on its outside for the fifth. 
 
 The fifth (v) has one on the base (i) for the cuboid, and 
 one on the inner side for the fourth metatarsal. It is 
 also remarkable for a tuberosity (2) on its outer part 
 which projects very much, gives attachment to a strong 
 ligament which supports the arch of the tarsus on the 
 outside, and marks its junction with the os cuboides, 
 which is immediately behind it. 
 
 The Connection of the metatarsal bones has been given 
 in their description. 
 
 The muscles attached to them are fourteen : viz. the 
 M. interossei (seven) & transversahs pedis, common to 
 all ; to the first metatarsal are attached M. tibialis anticus 
 & peroneus longus ; to the second, M. adductor poilicis 
 pedis ; and to the fifth, M. peroneus brevis, abductor & 
 flexor brevis minimi digiti. 
 
A DESCRIPTION OF THE BONES- 
 
 GO 
 
 THE TOES. Phalanges Digitorum Pedis. (C.) 
 
 Situation. Before the metatarsus. 
 Description. They consist of fourteen bones,* of 
 
 which there are but two 
 rows to the great toe, 
 pollex pedis, and three 
 to the other toes ; their 
 division is similar to that 
 of the fingers, into base, 
 body, and head, but they 
 are much shorter and 
 flatter. 
 
 The muscles attached 
 to them are nineteen ; viz. above, M. extensor proprius 
 poUicis & extensor longus & brevis digitorum pedis, in- 
 terossei (seven) ; belojv, M. flexor longus & brevis & 
 abductor pollicis, flexor longus & brevis digitorum & 
 lumbricales (four). 
 
 SESAMOID BONES. Ossa Sesamoidea 
 
 Of these there are two at the base of the first pha- 
 
 Q/% lanx of the great toe, givinsc insertion to the 
 ^^ M. flexor brevis & abductor pollicis pedis. 
 
 Under Surface, 
 
 * See page 61. 
 
TO 
 
 A DESCRIPTION OF THE BONES. 
 
 CHAP. V. 
 
 Of the Head. 
 
 The bones of the Head, cajiut, are twenty- two in 
 number, exclusive of the auditory bones and teeth, which 
 are forty in addition. > They are usually divided into 
 those of the skull, cranium, and face, fades; some of 
 them are in pairs, but others are only single bones. 
 
 To the Skull there are two pairs and two single bones; 
 viz. 
 
 2 Ossa parietalia(l). 
 
 2 temporum (2). 
 
 1 Os frontis (3). 
 
 1 — occipitis (4). 
 
A DESCRIPTION OF THE BONES. 
 
 71 
 
 To the Skull and 
 
 Face two single bones 
 are common ; viz. 
 
 lOs ethmoides(l), 
 1 — sphenoides (2). 
 
 To the Face there are six pairs and two single bones; 
 viz. 
 2 Ossa malarum (1). 2 Ossa palatina (5). 
 
 2 — maxillaria superiora (2). 2 turbinata(6). 
 
 2 Ossa nasi (3). 1 Vomer (7). 
 
 2 lachrymalia (4). 1 Os maxillareinferius (8). 
 
72 A DESCRIPTION OF THE BONES. 
 
 All these bones, with the exception of the ossa tem- 
 porum and os maxillare inferius, which form a gingly- 
 moid, or hinge joint, are united by that species of 
 SYNARTHROSIS, wliich is called suture, from its resem- 
 blance to the stitches of a seam. And here would 
 seem to be the proper place to describe the sutures, but 
 as they cannot be well explained, till the processes of 
 the different bones of the head have been spoken of, it 
 has been deemed best to defer the description of them 
 till the student has obtained a perfect knowledge of the 
 separate bones of the skull and face. 
 
 THE BONES OF THE SKULL, 
 
 Strictly so called, have been before mentioned as two 
 pairs and two single bones. 
 
 FRONTAL BONE. Os Frontis (1). 
 
 Situation. In the anterior superior part of the skull, 
 forming the forehead and part of the temples above, and 
 to the sides ; and the roof of the orbits below. 
 
 Description. The os frontis nearly resembles in shape 
 a clam shell : it is convex and regular before, concave 
 and slightly irregular behind : convex from before back- 
 wards, and from side to side above ; and irregularly con- 
 cave below. 
 
 On the External Surface, it is naturally divided into 
 
 two portions by the su- 
 perciliary ridges, arcus 
 super ciliares, situated at 
 the most anterior infe- 
 'Qr7'*s^ rior part of the bone ; 
 that which is above the 
 ridges is called the fronto-temporal portion (i) ; and that 
 behind them, the ethmoido-orbital portion (ii). 
 
A DESCRIPTION OF THE BONES. 
 
 
 In the Fronto-Temporal Portion are found, immedi- 
 ately above the su- 
 perciliary ridges, 
 the two frontal 
 prominences, pro- 
 tuheranticE fron- 
 tales (1, 1), just 
 above the inner 
 corners of the or- 
 bits, and marking 
 the situation of 
 the frontal sinuses, 
 sinus frontales : 
 about an inch above them, and rather to their outer side, 
 are two other projections (2, 2) which mark the beginning 
 of ossification : extending upwards and backwards from 
 the lowest part of the bone, in the mesial line is seen a 
 slight ridge (3, 3) more or less projecting, marking the 
 place at which the bone was divided into two portions in 
 the young subject, and also part of the course of the 
 lono-itudinal sinus of the dura mater within the skull : the 
 sides of this portion, forming the temples, are separated 
 from the forehead by the temporal arches, arcus tempo- 
 rales (4, 4,) which at first are very strongly marked be- 
 low, and become less distinct as they pass upwards and 
 backwards ; the hollows below form parts of the temporal 
 pits, fossce temporales (5, 5,) in which the M. temporales 
 rest. The posterior edge of the fronto-temporal portion 
 is deeply serrated as far as the temporal arches, and 
 bevelled from above downwards and forwards ; whilst that 
 below them is squamous, and slightly serrated downwards 
 and backwards. 
 
74 
 
 A DESCRIPTION OF THE BONES. 
 
 In the Ethmoido-Orbital Portion are found, 
 
 In the middle, 
 the nasal process, 
 iwocessus nasalis 
 (6), deeply den- 
 ticulated, and 
 springing out from 
 it, is the nasal 
 spine,5pi72« nasalis 
 (7); behind which is the ethmoidal notch, incisura ethmoi- 
 dalis (8) ; at the outer edges of the nasal process are the 
 two internal angular processes, processus angulares in- 
 terni (9, 9), and rising up from them, the superciliary 
 ridges, ai'cus super ciliares (10, 10) with a notch or hole, 
 the supra-orbitar ho\e, foramen supra-orbitare, (11, 11) in 
 each : as the ridges pass upwards, outwards, and down- 
 wards, to terminate in the external angular processes, 
 processus angulares externi (12, 12), the bone appears 
 pinched up, which, together with the hollows of the 
 temporal pits behind, render the external more distinct 
 than the internal angular processes ; behind and between 
 the angular processes are the two orbitar plates, lamellce 
 orhitares (13, 13) of a triangular shapC; the bases in front, 
 the apices behind, and truncated ; the orbitar plates are 
 concave from side to side, and deepest close by the exter- 
 nal angular processes, forming a cavity for the lacrymal 
 gland, called lacrymal pit, fossa lacrjjmalis (14, 14); be- 
 hind the internal angular process is a depression or a spine, 
 sometimes one, sometimes the other, to give attachment to 
 the pulley of the superior oblique muscle of the eye ; when 
 a spine, it is called spina trochlearis (15, 15) ; between 
 the orbitar plates and the edges of the ethmoidal notch 
 are found the openings of the frontal sinuses (16, 16). 
 
A DESCRIPTION OF THE BONES. 
 
 On the Internal Surface are found, in the fronto- 
 
 ' 1^^2r(/>v TEMPORAL PORTION, 
 
 numerous sbVht emi- 
 
 /«*.&' ,« >d^i%«n^^^^^B.<v^ nences, and broad 
 
 shallow depressions, 
 produced by the con- 
 volntions of the cere- 
 brum, and called, 
 ^ ^^^.W^] kiitmwUBm from their form, ma- 
 
 ix ,. .. k ^^^^^^ miliary eminences, 
 
 -^ eminentice mamillares 
 
 (17), and finger-like impressions, hnpress'wnes digitatce 
 (18) ; from the middle of the anterior part of the ethmoi- 
 dal notch, the internal spine, crista interna (19), com- 
 mences, which gives attachment to the dura mater, and 
 projecting sharply backwards, extends upwards about 
 an inch, and divides into two ridges, with a small cavity 
 between them, continued up to the posterior edge of the 
 bone, and called frontal furrow, sulcus frontalis (20), in 
 which part of the longitudinal sinus is lodged : it is said, 
 that when the frontal bone remains divided in the adult, 
 there is no spine. Immediately behind the commence- 
 ment of the frontal spine is the foramen ccecum (21). 
 On either side of the spine is a concavity, which receives 
 the anterior lobes of the cerebrum, and answers to the 
 prominences marking the commencement of ossification. 
 The upper part of the ethmoido-orbital portion sup- 
 ports the anterior lobes of the cerebrum, and is marked 
 by eminentiae mamillares and impressiones digitatae. 
 
 The Foramina in the os frontis are five perfect and 
 six imperfect. The five perfect are, 
 
 1. Foramen ccecum (21), situated in the inside of the 
 
76 A DESCRIPTION OF THE BONES. 
 
 bone at the root of the spine, giving attachment to the 
 dura mater, and allowing the passage of a vein. 
 
 2 & 3. The openings (16, 16) of the frontal sinuses, 
 between the ethmoidal notch and the orbitar plates. 
 
 4 & 5. Foramina frontalia (22, 22) one behind each 
 internal angular process, through which a branch of the 
 supra-orbitary nerve passes into the frontal sinuses. The 
 six imperfect are, 
 
 1 & 2. Foramina siipra-orhitaria (11, 11), usually 
 completed by ligament, situated in the superciliary ridges, 
 about one-third of their length from the internal angular 
 processes, for the passages of the supra-orbitary nerve, 
 
 artery, and vein. 
 
 3 & 4. Foramina orhitaria interna anteriora (23, 23), 
 
 placed about half an inch behind the lowest edge of the 
 nasal process in each orbitar plate, and giving passage to 
 the ethmoidal branch of the supra-orbitary nerve and 
 artery, into the ethmoidal cells and skull. 
 
 5 & 6. Foramina orhitaria interna posteriora (24, 24), 
 about half an inch behind the anterior, for the passage of 
 the branch of an artery. The four last foramina are com- 
 pleted by the ethmoid bone. 
 
 Junction. The os frontis is joined above and behind 
 with the ossa parietalia, wdiich junction terminates at a 
 line running horizontally backwards from the point of the 
 outer angular process ; between those two points, and be- 
 hind as far as the ethmoidal notch, it joins with the 
 sphenoid bone on each side : within the ethmoidal notch 
 it receives the ethmoid bone which joins to the orbitar 
 plates, at the anterior part of which it unites with the os 
 lacrymale ; before it joins by its nasal process and spine 
 with the ossa nasi, ossa maxillaria superiora, and ethmoid 
 
A DESCRIPTION OF THE BONES.' 
 
 77 
 
 bone, and by its outer angular processes with the malar 
 bones. 
 
 The muscles attached to the os frontis are three pairs ; 
 viz. M. temporalis, corrugator supercilii, & orbicularis 
 palpebrarum, and it is also covered by M. occipito fron- 
 talis. 
 
 PARIETAL BONES. Ossa Parietalia (2). 
 A pair. 
 
 Situation. At the superior and lateral parts of the 
 skull, forming the vertex or top of the head, and parts of 
 the temples. 
 
 Description. Externally (ci) convex and smooth from 
 T-^-~^^, * before to behind, 
 
 ^---_^ but rather flat an- 
 
 ^(^ l^ teriorly, convex 
 
 ^i } from side to side : 
 
 1, internally (b) con- 
 
 ^ ' cave from before 
 \ r backwards, and 
 
 from side to side, 
 and marked by 
 the convolutions of 
 the cerebrum. It 
 - , ^ • is divided into four 
 angles and four edges ; the anterior superior, the frontal 
 angle, angulus frontalis (1), sharp ; the posterior supe- 
 rior, the occipital angle, angulus occipitalis, (2), also 
 sharp ; the anterior inferior, the sphenoidal angle an- 
 gulus sphenoidalis (3), truncated ; the posterior inferior, 
 the temporal angle, angulus temporalis (4), also trun- 
 cated : the anterior edge is called the frontal edge, margo 
 frontalis (5) ; the superior, the parietal edge, margo pa- 
 
 \ 
 
 W 
 
'8 
 
 A DESCRIPTION OF THE BONES. 
 
 rietalis (6) ; the posterior, the occipital edge, margo oc- 
 cipitalis {7) ; all three of which are deeply serrated ; and 
 the inferior is the temporo-sphenoidal edge, margo tem- 
 jioro-sphenoidalis (8), the posterior part of which is 
 slightly serrated, and the rest of it is squamous ; this 
 edge is of a semicircular form, whilst the other three are 
 nearly straight. About two inches above the lower edge, 
 the temporal arch (9) extends backwards from the os 
 frontis in a semicircular direction along this bone, and 
 terminates at the anterior point of its temporal angle. 
 There is usually a mark in the centre of the bone, point- 
 ing out the beginning of ossification (10). 
 
 On the internal surface of the bone, running along 
 
 the upper edge, 
 
 is part of a groove 
 
 itudi- 
 
 (11). 
 
 for the longitudi- 
 nal sinus 
 which is com- 
 ^ pleted when both 
 bones are united ; 
 and frequently to 
 the outer edge of 
 this, several little 
 pits giving lodge- 
 ment to the glan- 
 dulae pacchionise. 
 In the anterior 
 point of the sphenoidal angle internally is a groove (12) 
 sometimes a complete canal for the middle artery of 
 the dura mater, which passes upwards and marks the 
 bone with its ramifications : on the posterior point of 
 the temporal angle internally there is a broad groove 
 (^13), for part of the lateral sinus. 
 
A DESCRIPTION OF THE BONES. 
 
 9 
 
 [Foramen. Only one, foramen farietale (14), near 
 the upper edge, for the passage of a vein to the longitu- 
 dinal sinus. 
 
 The only muscle attached to it is the M. temporalis ; 
 the M. occipito frontalis passes over it. 
 
 Junctions. By its frontal edge, with the os frontis ; by 
 itsparietal edge, with its fellow ; by its occipital edge, with 
 the osoccipitis ; and by its temporo-sphenoidal edge, with 
 the temporal bone behind, and the sphenoid bone before. 
 
 OCCIPITAL BONE. Os Occipitis. 
 
 Situation. In the posterior and under part of the 
 skull, forming the occiput or hind-head, and part of the 
 base of the skull. 
 
 Description. Con- 
 vex behind («), con- 
 cave before {h) ; of 
 an irregular hexago- 
 nal figure, the long 
 axis beino; from above 
 to below ! the supe- 
 rior angle sharp, the 
 occipital angle, angii- 
 his occij)itaUs {\) , the 
 two superior lateral 
 angles obtuse, the 
 parietal angles, an- 
 gidi par iet ales (2, 2) ; 
 the two inferior an- 
 frles obtuse, the tern- 
 poral angles, anguli 
 temporales (3, 3), and 
 
80 
 
 A DESCRIPTION OF THE BONES. 
 
 
 tl»e anterior inferior angle truncated, the sphenoidal 
 angle, angulus sphenoidalis (4). The two superior edges, 
 between the occipital and parietal angles, rather convex 
 and serrated ; the parietal edges, margines parietales 
 (5, 5), the two lateral edges between the parietal and 
 temporal angles, concave and deeply denticulated ; the 
 temporal edges, margines temporales {Q^6) \ the two 
 anterior edges, between the temporal and sphenoidal 
 angles, also concave, and irregularly plane ; the basilar 
 edges, margines hasilares (7, 7). 
 
 The External Surface {a) is smooth above a hori- 
 zontally curved 
 ''^ line which is called 
 
 the superior trans- 
 verse arch, arcus 
 transversus supe- 
 rior (8, 8) ; in the 
 middle of which 
 is the external occi- 
 pital protuberance, 
 protuherantia occi- 
 pitalis externa (9) ; 
 and to these are 
 attached above the 
 , M. occipito fron- 
 h) tales, and hclow on 
 each side the M. 
 trapezii & com- 
 plex! ; aboutan inch 
 below is the inferior transverse arch, arcus transversus 
 inferior (10, 10), to which is attached the M. splenii, 
 recti postici mnjores, and obliqui superiores capitis ; from 
 
A DESCRIPTION OF THE BONES. 81 
 
 the external occipital protuberance passes down perpen- 
 dicularly, the occipital spine, spina occipitalis (11), di- 
 viding the posterior inferior part of the bone into two parts ; 
 and on each side of it, below the inferior transverse arch, 
 are the occipital pits, sulci occipitales (12, 1*2), into which 
 the M. recti postici minores capitis are inserted. The 
 under and fore part of the bone then bifurcates, and di- 
 verging, forms the posterior part of the gre^t\\o\e, foramen 
 magnum (13) ; it then converges, forms the fore part of 
 the same foramen, and sends out a strong process anteri- 
 orly, the basilar process, j^^ocessus hasilaris (14), which 
 terminates in the anterior angle, and that being truncated 
 and rough, forms the sphenoidal process, processus sphe- 
 noidalis {15) ; on the anterior lateral edges of the foramen 
 magnum are situated the condyloid processes, processus 
 condijloides (16, 16), which are of an irregular oval shape, 
 with their axes from before to behind, and facing down- 
 wards, outwards, and backwards, so that their anterior 
 and inner edge is the deepest ; they are convex from be- 
 fore to behind, slightly convex from side to side ; and by 
 them the head articulates with the first cervical vertebra : 
 extending from the condyloid processes laterally outwards 
 and rather backwards to terminate at the temporal angles, 
 is a ridge on each side (17, 17) which gives attachment to 
 the M. rectus lateralis capitis, and before them in the 
 basilar edges, the bone is scooped out on each side to 
 form part of the foramina lacera basis cranii posteriora 
 (18, 18) ; behind the condyloid processes are the fora- 
 mina condyloidea posteriora (19, 19), and before them the 
 foramina condyloidea anteriora (20, 20). 
 
82 
 
 A DESCRIPTION OF THE BONES. 
 
 The Internal Surface of the Bone is divided behind 
 
 the foramen mag- 
 num into four ca- 
 vities (21, 22) by 
 the crucial ridge, 
 the perpendicular 
 portion of which 
 is called the inter- 
 nal spine, spina 
 interna (23, 23), 
 and the transverse, 
 the transverse 
 spine, spina trans- 
 versa (24, 24) ; 
 and where they 
 intersect is the 
 internal occipital 
 protuberance, /9ro- 
 tuherantia occipitalis interna (25) : the internal spine 
 above the transverse spine has usually a deep groove 
 on its right side (26) for the longitudinal sinus, and 
 helorv it a narrow groove (27) for the occipital sinus ; the 
 transverse spine is more or less hollowed on one or both 
 sides (28, 28) for the lateral sinuses. To the spine, above 
 the transverse spine, is attached the falx major of the 
 dura mater, and to the same part below, the falx minor 
 is connected ; to the transverse spine the posterior edge 
 of the tentorium is fixed. The cavities above the trans- 
 verse spine (21,21) are for the posterior lobes of the 
 cerebrum, and those below (22, 22) for the cerebellum, 
 and at their anterior extremities are more or less of the 
 terminations of the grooves (29, 29) for the lateral sinuses 
 
A DESCRIPTION OF THE BONES. 80 
 
 in the foramina lacera, with the posterior condyloid fora- 
 mina opening into each of tliem. The upper surface of 
 the basilar process (14) is seen hollowed out, broad be- 
 low, and narrow above, to receive the medulla oblongata ; 
 and on its superior edges are seen parts of the grooves 
 (30, 30) for the inferior petrosal sinuses. 
 
 The Foramina in the os occipitis are five perfect and 
 two imperfect. The five perfect are, 
 
 1. Foramen magnum (13), rather of an oval figure, 
 with the Ions axis from before to behind, through which 
 pass out of the skull the medulla oblongata, and the an- 
 terior arteries of the medulla spinalis, and into it the ver- 
 tebral arteries and accessory nerves. 
 
 2 & 3. Foramina condylo'idea anteriora (20, 20), situ- 
 ated within the lateral edges of the foramen magnum, 
 through which the lingual nerves pass. 
 
 4 & 5. Foramina condyloidea posterior a (19, 19), by 
 which veins from the back part of the neck enter into 
 the lateral sinuses. The two imperfect are, 
 
 1 & 2. Foramina lacera basis cranii posterior a (l^, 18), 
 completed by the temporal bone, through which pass the 
 glossopharyngeal, pneumo-gastric, and accessory nerves 
 from the skull, and at which the lateral sinus joins with 
 the internal jugular vein. 
 
 Junctions. The os occipitis is joined by its parietal 
 edges to the parietal bones ; by its temporal edges to the 
 mamillary portions of the temporal bones ; by its basilar 
 edges to the petrous portions of the same bone ; and by 
 its sphenoidal process to the sphenoid bone. 
 
 The muscles attached to the os occipitis are eleven 
 pairs ; viz. the M. trapezii, complexi, splenii, recti pos- 
 tici majores, & minores capitis, obliqui superiores capitis, 
 
 G 2 
 
84 
 
 A DESCRIPTION OF THE BONES. 
 
 recti laterales, recti interni majores, & minores capitis, 
 constrictores pliaryngis superiores, & occipito-frontales. 
 
 TEMPORAL BONES. Ossa Temporum (2). 
 
 A pair. 
 
 Situation. In the inferior, middle, and lateral parts 
 of the skull, forming parts of the temples and cheeks. 
 
 Description. It is of an irregular shape, thin before 
 and above, and thick behind and below, sending from 
 
 within a strong triangular process, which passes forwards, 
 inwards, and downwards, and being of a close texture 
 and rocky hardness, is called the pars petrosa (in) ; it 
 naturally divides the other part of the bone into two ; 
 that which is before, and to the outer side of it, is called 
 jjars squamosa (i), from its being thin like a fish-scale ; 
 and that which is behind, and to its outer side, the pars 
 mamillaris (ii), from its resemblance to a nipple. 
 
 The Pars Squamosa (T), 
 
 Is situated in front; it is bounded below by the 
 meatus auditorius externus, which is the largest external 
 hole, and above by the petrous portion. 
 
A DESCRIPTION OF THE BOXES. 
 
 85 
 
 The superior part of the pars squamosa is very thin, 
 
 and called the scaly 
 
 plate, lamella squamosa 
 (1) : it forms externally 
 (a) part of the temporal 
 fossa, from the under 
 and outer part of which 
 extends the root of 
 the zygomatic process, 
 processus zygomaticus 
 (2), which is thin and 
 narrow, facing down- 
 wards and inwards, it 
 passes forwards, curves 
 slightly inwards, is 
 smooth above, but ir- 
 regular, and having a 
 tubercle (3) at its root 
 
 W4 
 
 Internal Surface. 
 
 below, and terminates in a denticulated process, the malar 
 process, processus malaris (4) ; between the root of the 
 zygomatic process above, and the scaly plate, is the tem- 
 poral pulley, trochlea temporalis (o), over which the M. 
 temporalis plays; behind the root of the same process 
 below is the glenoid cavity, caviias articularis (6), for 
 the articulation of the lower jaw, bounded behind by 
 the glasserian fissure, Jissura glasseri (7), and before by 
 the articular eminence, eminentia articularis (8), broadest 
 within, and narrowest without, where it terminates in 
 the tubercle of the zygomatic process. 
 
 Within (6), the squamous part is marked by the con- 
 volutions of the middle lobes of the cerebrum, and the 
 edge bevelled off, where it joins with the parietal bone. 
 
86 
 
 A DESCRIPTION OF THE BONES. 
 
 The Pars Mamillaris (II), 
 
 Situated at the posterior inferior part of the bone, 
 bounded before and above by the pars petrosa, and below 
 by the auditory process. 
 
 It forms an irregular semicircular ridge above, to join 
 with the parietal bone, and behind is deeply denticu- 
 
 External Surface. Internal Surface. 
 
 lated to join with the occipital bone. At the under part, 
 externally (a), it is shaped like a nipple, and called, 
 at that part, mastoid process, processus mastoideus (9), 
 upon which is a small groove (10) for the occipital artery, 
 and above it usually is seen the mastoid hole, foramen 
 mastoideum (11); behind the mastoid process is a deep 
 pit, the digastric pit, fossa digastrica (12), from which 
 the M. digastricus arises. 
 
 On the inside (6) of this part, the mastoid process is 
 deeply hollowed, to receive the termination of the lateral 
 sinus (13); and between it and the squamous part, the 
 substance of the bone is cellular, forming the mastoid 
 cells, cellulce mastoidece, which are not seen but by 
 making a section of the bone. 
 
 The Pars Petrosa (III), 
 Situated on the inside of the bone, passing forwards, 
 inwards, and downwards from the junction of the squamous 
 
A DESCRIPTION OF THE BONES. 
 
 8: 
 
 Anterior face. 
 
 with the mamillary portions, is of a triangular shape with 
 the base below. 
 
 It has three angles and three faces. The superior 
 
 angle (14) has a broad 
 shallow depression (15) 
 near its inner point, over 
 which the trigeminal 
 nerve passes ; and, ex- 
 tending aloncr from 
 thence to the upper part 
 of the pit in the mastoid 
 process, is a groove 
 (16), for the superior 
 petrosal sinus. In the 
 anterior inferior angle 
 (17) is the bony part of 
 the Eustachian tube, 
 tuba eustachiana (18): 
 and above it, part of the 
 carotid canal (19) ; the 
 extreme inner point 
 Posterior face. (^O) is rough, to join 
 
 with the root of the posterior clinoid process of the 
 sphenoid bone. The j^^^t^^^or inferior a?igle (21) is 
 very irregular ; it has a deep notch in it, which forms 
 part of the posterior lacerated hole at the base of the 
 skull, foramen lacerum basis cranii posterius (22), 
 divided into two by a jutting process, jugular process, 
 processus jugularis (23), which separates the nerves pass- 
 ing through this hole from the iugular vein: in the inner 
 notch, the aqueduct of the cochlea, aquceductus coclilece 
 (24), opens, presenting a conical cavity with its base 
 
88 
 
 A DESCRIPTION OF THE BONES. 
 
 facing backwards and downwards. In the anterior face 
 is seen to the inner point a slight notch (2.")), forming 
 part of the carotid hole, to the outer side of which is the 
 continuation of the groove (2G) for the trigeminal nerve ; 
 and below it, part of the anterior lacerated hole at the 
 base of the skull, foramen lacerum basis cranii anterius 
 (27), which, before maceration, is filled up by a liga- 
 mentous structure, and forms part of the carotid canal : 
 extending outwards and upwards from this is the unnamed 
 canal, canalis innominatus (28), which terminates in the 
 unnamed hole, foramen innominatum (29) ; and still 
 further out is seen the projection of the vertical semi- 
 circular canal (30). In the posterior face are, at the 
 extreme inner part, a portion of the groove (31) for 
 lodging the inferior petrosal sinus, the remainder of it 
 being situated on the basilar process of the os occipitis; 
 to the outer side of this is seen the internal auditory hole, 
 foramen auditivum internum (32), leading to the internal 
 auditory passage, meatus auditorius internus, and still 
 further out, the opening of the aqueduct of the vestibule, 
 aqu(^ductus vestihuli (33), covered by a scale of bone. 
 
 In the inferior face or 
 z^OjA base is the jugular pit, 
 fossa jugularis (34), in 
 shape like a thimble, 
 for the termination of 
 the jugular vein imme- 
 diately before the notch 
 of the foramen lacerum 
 Inferior fact. postcrius ; oxi thc outcr 
 
 side of the pit is seen the styloid process, processus sty- 
 liformis (35), from which arise three muscles and two 
 
A DESCRIPTION OF THE BONES. 
 
 89 
 
 ligaments ; it is surrounded by its vaginal process or 
 sheath, processus vaginalis (36), from which it may be 
 drawn out ; between the root of the styloid process and 
 the fore part of the digastric pit is the stylo-mastoid 
 hole, foramen stylo-mastoideum (37), the external open- 
 ing of the canal of that name, which passes through the 
 top of the tympanum, but cannot be seen till a section of 
 the bone be made : in front of the styloid process and 
 the jugular pit is seen the auditory process, processus 
 
 auditivus (38), which 
 forms the floor of 
 the external audi- 
 tory passage, meatus 
 auditorius externus ; 
 the auditory process 
 is slightly hollowed 
 to receive part of the 
 
 ILrtemol surface. P^rOtid gknd, aud 
 
 has above it the external auditory \\o\e, foramen auditivum 
 externum (39) ; and behind its inner point the external 
 opening of the carotid canal (40). The posterior and 
 inner part of this face is truncated obliquely and irre- 
 gularly upwards. 
 
 The Foramina in this bone are ten whole and three 
 imperfect. The ten perfect are, 
 
 1. Foramen glenoideum (41) in the fissura glasseri, 
 for the passage of the Nervus chorda tympani from the 
 tympanum, and the M. externus mallei into it. 
 
 2. Foramen auditivum externum (39), between the 
 auditory and the mastoid process to which the auricle of 
 the ear is attached, and which is the beginning of the 
 bony part of the external auditory passage. 
 
90 A DESCRIPTION OF THE BONES. 
 
 3. Foramen stylo-mastoideum (37), between the mas- 
 toid and styloid processes for the passage of the facial 
 nerve from the stylo-mastoid canal. 
 
 4. Foramen mastoideum (11), generally behind and 
 above the mastoid process, but sometimes found between 
 the temporal and occipital bones, and at other times 
 though rarely, entirely in the latter bone ; it transmits 
 a vein from the integuments of the skull to the lateral 
 sinus. 
 
 5. The opening (24) of the aquseductus cochleaa. 
 
 6. Ditto (40) carotid canal. 
 
 7. Ditto (18) Eustachian tube. 
 
 8. Foramen innominatum (29), in the anterior face of 
 the pars petrosa, for the passage of the nervus innomi- 
 natus to the beginning of the stylo-mastoid canal, to join 
 with the facial nerve. 
 
 9. Foramen auditivum internum (32), by which the 
 facial and auditory nerves ent(;r the meatus auditorius 
 internus. 
 
 10. The ojoening (33) of the aquseductus vestibuli. 
 The two last holes are in the posterior face of the pars 
 petrosa. The imperfect foramina are, 
 
 1. Foramen lacerum basis cranii anterius (27) filled 
 in the recent state by ligament, forming part of the 
 carotid canal. 
 
 2. Foramen caroticum (25) for the passage of the 
 internal carotid artery in the skull. 
 
 3. Foramen lacerum basis cranii posterius (22) for 
 the passage of the glossopharyngeal, pneumo-gastric, and 
 accessory nerves, and the junction of the jugular vein 
 with the lateral sinus. 
 
 Junctions. The os temporis is joined by its malar 
 
A DESCRIPTION OF THE BONES. 91 
 
 process to the zygomatic process of the os malae ; by the 
 inferior edge of the pars squamosa to the spinous process 
 of the OS sphenoides ; by the superior edge of the same 
 part to the temporo- sphenoidal edge of the os parietale, 
 by the superior edge of the pars mamillaris to the tem- 
 poral angle of that bone ; by the inferior edge of the pars 
 mamillaris, and by the posterior inferior angle of the pars 
 petrosa to the temporal and basilar edges of the os occi- 
 pitis ; and by the inner point of the pars petrosa to the 
 root of the posterior clinoid process of the os sphenoides. 
 
 The muscles attached to the os temporis are nineteen ; ^ 
 viz. M. temporalis, masseter, retrahentes aurem (two), 
 occipito-frontalis, sterno-mastoideus, trachelo-mastoideus, 
 splenius, digastricus, tensor Sc levator palati, stylo-hyoi- 
 deus, stylo-glossus, stylo-pharyngeus, & constrictor 
 pharyngis superior ; and the muscles moving the small 
 bones of the ear, M. tensor tympani, laxator tympani, 
 externus mallei, & stapedius. 
 
 The OS temporis contains, besides the parts which 
 have been described, the organ of hearing,* including 
 the ossicula auditus, viz. malleus, incus, os orbiculare, 
 and stapes. As, however, these cannot be understood, 
 till sections of the os temporis have been made, it will 
 be better to defer the whole, rather than to describe the 
 organ of hearing partially in this place. 
 
 ETHMOID BONE. Os Ethnoides. (1). 
 
 Situation. In the ethmoidal notch of the os frontis, 
 and forming the roof of the nostrils. 
 
 Description. The ethmoid bone derives its name 
 
 * See chap. viii. sect. 4. 
 
92 
 
 A DESCRIPTION OF THE BONES. 
 
 Superior Jf posterior $tirfaces. 
 
 from its resemblance to a sieve, being full of holes ; it is 
 of a cuboidal figure, and made up principally of cells. 
 
 The superior surface of the bone is called its cribri- 
 form plate, lamella cribriformis (1, 1), which has in the 
 middle the cock's comb, crista galli 
 (2), to which the beginning of the 
 falx major of the dura mater is at- 
 tached ; it is thin and narrow at the 
 back part of the cribriform plate, 
 but as it advances it becomes deeper 
 and broader, where it is sometimes 
 hollowed to form part of the foramen 
 caecum ; on each side of the cock's 
 comb are numerous little holes, the sieve-like holes, fora- 
 mina crihrosa (3, 3) ; from the under part of the crest 
 descends the nasal plate, lamella 
 nasalis (4), thick behind, and above 
 (a) where it joins with the ethmoidal 
 process of the sphenoid bone, thin 
 behind and below (6), where it joins 
 with the vomer, very much thicker 
 before and above (c), directly under 
 the crista galli, where it joins with 
 the crista nasalis of the frontal bone, 
 and thick below and before (d), 
 where it joins with the septal carti- 
 lage of the nose ; on either side of 
 the nasal plate, which forms a divi- 
 sion between them, are the convo- 
 lutions of the bone, which coalescing 
 Anur\or iurfaet. form the ethmoidal sinuses, sinus 
 
 eihmoidales (5, 5), anterior and posterior, the former 
 
A DESCRIPTION OF THE BONES. 93 
 
 (11, 11) terminating in the middle, and the latter (10, 10) 
 in the superior chambers of the nose ; two of these long 
 convolutions, which are nearest to the nasal plate, descend 
 further, are more distinct, have their concavities out- 
 wards, and are called turbinated plates, lamellce turhinatce 
 (6, 6) ; the spaces between the turbinated plates below, 
 and the under part of the cribriform plate above, are 
 called the superior chambers of the nose, meatus supe- 
 riores nasales (7, 7) ; the spaces below them, and to their 
 outer surfaces, form part of the middle chambers of the 
 nose, meatus medii nasales : the ethmoidal sinuses are 
 bounded externally for the most part by the flat plates, 
 lamellce plancB (8, 8), which form 
 the principal portions of the inside 
 of the orbits, but at the anterior part 
 (9), where the frontal and ethmoidal 
 sinuses send their canals to termi- 
 nate in the middle chamber, they are 
 Lateral surface. covcrcd by tlic ossa lacrymalia. 
 
 The Foramina in this bone are, numerous perfect, 
 and three imperfect pairs. The perfect are 
 
 Foramina cribrosa (3, 3), through which the olfactory 
 and ethmoidal nerves pass to the nose. 
 
 The openings (10, 10) of the posterior ethmoidal 
 sinuses. The imperfect foramina are 
 
 1. The oj)enings (lit 11) of the anterior ethmoidal 
 sinuses. 
 
 2 & 3. Foramina orhitaria interna anteriora (12, \'2) 
 S^ posleriora (13, 13), in the upper edge of the fiat plate 
 completed by the os frontis, through the anterior of which 
 the ethmoidal nerve passes up into the skull, and through 
 the posterior an artery and vein to the ethmoidal sinuses. 
 
94 
 
 A DESCRIPTION OF THE BONES. 
 
 Junctions. Tlie os ethmoides is joined above by the 
 edges of its cribriform plate to the edges of tlie ethmoidal 
 notch of the os frontis, and to the os sphenoides ; and by 
 the posterior part of its nasal plate to the latter bone 
 and to the vomer ; by the fore part of the same plate to 
 the back part of the nasal crest of the os frontis ; by the 
 anterior edge of its flat plate with the os lacrymale ; and 
 by the lower edge of the same plate with the superior 
 maxillary bone and palate bone. 
 
 There are not any muscles attached to or covering 
 this bone. 
 
 SPHENOID BONE. Os Sphenoides. (2). 
 
 Situation. In the middle of the skull, immediately 
 behind the bones of the face. 
 
 Description. This bone is called sphenoid or wedge 
 bone, because it seems to wedge and lock together all the 
 
 other bones of the skull. It is divided into the body, 
 corpus (i), two temporal pordons, partes temporales (ii, ii), 
 and two pterygoid portions, partes pterygoidece (iii, iii). 
 
A DESCRIPTION OF THE BONES. 
 
 95 
 
 The Body (i), 
 
 Is situated in the middle of the bone, and may be 
 said to resemble an oblong square box, with its long axis 
 from before to behind ; it is bounded before by its nasal 
 surface, fades nasalis (1), behind by its occipital surface, 
 
 fades occipi- 
 
 talis (2), and 
 laterally by a 
 perpendicular 
 line, raised 
 from the pro- 
 cessus ptery- 
 
 Suptrior surface. 
 
 goidei (3, 3), the most depending part of the bone. 
 On the middle of the upper part of the body is the 
 Turkish saddle, sella turcica (4) concave from before 
 to behind, and in it rests the pituitary gland of the 
 brain ; the sella turcica is bounded behind by a broad 
 process, the posterior clinoid process, processus clinoides 
 posterior (5), so called from its supposed resemblance to 
 the knob of a bedstead ; it is, however, nearly flat above, 
 with a trifling cavity from side to side ; it is bounded 
 before by the olive-shaped process, jwocessiis olivaris, 
 (6), which is usually hollowed, and upon it the optic 
 nerves decussate, or at least join : on each side of this 
 process, and extending back over the sella turcica are 
 the anterior clinoid processes, processus clinoides ante- 
 riores (7, 7), two in number, having in their roots the 
 optic \io\es, foramina optica (8, 8) : sometimes the ante- 
 rior and posterior clinoid processes are united by a slip 
 of bone running from one to the other ; at other times, a 
 little bony process is sent down from the anterior clinoid 
 processes to the outer edges of the processus olivaris, so 
 
9G 
 
 A DESCRIPTION OF THE BONES. 
 
 that the transverse artery of the brain passes through 
 complete foramina; extending forwards and outwards 
 from the anterior clinoid processes, and terminating in 
 points as they pass out, are the transverse spinous pro- 
 cesses, processus transverso-sp'inosi (9, 9), which are thin 
 
 and triangu- 
 lar, their bases 
 attached to the 
 body of the 
 bone,and their 
 points extend- 
 ing outwards : 
 
 hijerior surface. lu frOnt of the 
 
 body is the ethmoidal spine, sp'nia ethmo'idalis (10) ; 
 below and before which is the ethmoidal process, pro- 
 cessus ethmo'idalis (11); the body contains the two sphe- 
 noidal sinuses, sinus sphcnoidales (12, 12), divided by a 
 plate of bone (13), and opening into the superior cham- 
 ber of the nose ; on its under surface is the single -pro- 
 cess, processus azygos (14), on either side of which are 
 the parts called by some anatomists the triangular bones, 
 ossa triangularia (15, 15), and described by them as dis- 
 tinct bones ; they merely form the floor of the sinuses 
 and the roof of the spheno-palatine ho\e^, foramina spheno- 
 palatina, by which the spheno-palatine nerves pass into 
 the nose : the occipital surface of the bone faces rather 
 downwards and is rough, forming 
 the basilar process, processus basi- 
 laris (16); on each side of which is 
 a deep notch, forming part of the 
 foramen caroticum (17, 17) : on each 
 side of the body is a groove for the internal carotid 
 artery (18, 18). 
 
 I'osterwr surjnce. 
 
A DESCRIPTION OF THE BONES. 
 
 97 
 
 The Temporal Portions (ii, ii), 
 Are placed to the outer sides of the imaginary L'nes 
 above described ; they pass first outwards, and after- 
 wards upwards laterally, and forwards : they are hol- 
 lowed within, and form, with the squamous and petrous 
 portions of the temporal bones, the cavities for lodging 
 the middle lobes of the cerebrum ; whilst the anterior 
 ascending part separates the general cavity of the skull 
 
 from the orbits. Internally be- 
 tween the anterior inner edge 
 of the temporal portion and the 
 transverse spinous process, is 
 situated the superior lacerated 
 orbitar hole, foramen lacerum 
 orh'itare superius (19, 19), of an 
 irregular shape, largest below 
 and to the inside, and becoming 
 pointed as it extends outwards ; behind and below it is 
 the round hole, foramen rotundum (20, 20) ; extending 
 backwards from which is a groove (21,21) for the lodge- 
 ment of the superior maxillary nerve ; more backwards, 
 and to the outer side, is the oval hole, foramen ovale 
 
 (22, 22), and behind it, in the 
 extreme angle, is the spinous 
 hole, foramen sp'inosum (23, 
 23). The anterior upraised 
 surface of the pars temporalis 
 forms the orbitar plate, lamella 
 orh'itar'is (24, 24), facing up- 
 wards and inwards, forming 
 the back and outer part of the 
 orbit ; it is of a triangular shape, with the base forwards 
 
 Anterior if external surfaces. 
 
 23 
 Superior surface. 
 
 H 
 
98 A DESCRIPTION OF THE BONES. 
 
 and outwards ; its lower edge (25) forms the upper mar- 
 gin of the inferior lacerated orbitar hole, or spheno- 
 maxillary fissure, /o/Y/ wen lacerum orhitare inferlus. The 
 outer surface, joining at an obtuse angle with the orbitar 
 plate, is the temporal plate, lamella temporalis (26, 26), 
 which forms part of the fossa temporalis ; extending back 
 from the temporal fossa is the spinous process, processus 
 sp'inosus (27, 27), which passing backwards, dips down, 
 and forms a little process, the styloid process, processus 
 styliformis (28, 28). 
 
 The Pterygoid Portions (hi, hi) : 
 Are situated at the under part, on either side of the 
 body of the bone, extending downwards from its junction 
 
 with the temporal portions ; 
 they bound above, and to the 
 sides, the posterior openings 
 of the nostrils. Each pars 
 pterygoidea is divided into 
 Posterior surface. '' two plates, lam'inxB (29, 29'), 
 
 having posteriorly, between each two, the pterygoid pits, 
 fossce 2^terygoidece {SO, SO), which, as the laminae pass down 
 and separate, terminate in the pterygo-palatine fissures, 
 Jissurce 'pterygo-palatincB (31,31), the nasal plate, lamina 
 nasalis (29', 29'), is the longest, it faces slightly outwards, 
 and terminates in a little curved process, the hook-like 
 process, j^^ocessus hamularis (32, 32), over which the 
 tendon of the M. tensor palati plays : the outer plate is 
 the muscular plate, lamina muscularis (29, 29), which is 
 the broadest and strongest, but shortest; it faces consider- 
 ably outwards and forwards, and is deeply hollowed 
 behind. On the upper and fore part is seen the begin- 
 ning of the pterygo-palatine canal, canalis pterygo- 
 
A DESCRIPTION OF THE BONES. 
 
 99 
 
 palatinus (33, 33), by which the palatine nerve passes 
 
 into the mouth ; the anterior 
 ~^&k^'HX^7^'^^''^^iWIMiii^ surfaces of both laminae are 
 
 roughly marked (34, 34") 
 where they join with the pa- 
 late, and superior maxillary 
 bones. 
 
 Antn-ior surface. ThE FoRAMINA iu the OS 
 
 sphenoides are seven pairs perfect and four imperfect. 
 The perfect foramina are, 
 
 1. Foramina optica (8, 8), for the passage of the 
 optic nerves and ocular arteries from the skull. 
 
 2. Foramina lacera orhitaria superiora (19, 19), for 
 the passage of the common oculo-muscular, inner oculo - 
 muscular, ophthalmic branch of the trigeminal, and the 
 outer oculo-muscular nerves from the skull, and of the 
 ocular veins into it. 
 
 3. Foramina rotunda (20, 20), for the superior max- 
 illary branch of the trigeminal nerve. 
 
 4. Foramina ovcdia (22, 22), for the inferior maxillary 
 branch of the trigeminal nerve. 
 
 5. Foramina spinosa (23, 23), for the middle artery 
 of the dura mater. 
 
 6. Foramina pterygoidea (35, 35), at the roots of the 
 pterygoid processes for the passage of the pterygoid 
 nerve. 
 
 7. The openings (36, 36) of the sphenoidal sinuses 
 on either side of the processus azygos. The imperfect 
 are, 
 
 1. Foramiyia carotica (17, 17), in part formed by the 
 temporal, and part by the sphenoid bone for the carotid 
 artery. 
 
 h2 
 
100 A DESCRIPTION OF THE BONES. 
 
 2. Foramina lacera basis cranii anteriora (37, 37), 
 completed by the temporal bone, and filled up naturally 
 with ligament. 
 
 3. Foramina spheyio-palatina (15, 15), formed by 
 the sphenoid, and palate bones, for the passage of the 
 spheno-palatine nerve into the nose. 
 
 4. Foramina lacera orbitaria inferiora (25, 25), 
 formed by the sphenoid, palate, and superior maxillary 
 bones. 
 
 Beside the foramina, the sphenoid bone, forms with 
 the OS palati, the canalis pterygo-'palatiiius (33,33). 
 
 Junctions. The os sphenoides is joined by its eth- 
 moidal spine and process to the nasal plate of the os eth- 
 moides ; by its transverso-spinous processes, and the inner 
 upper edges of its orbitar plates to the orbitar plates and 
 temporal edges of the os frontis ; and at the upper and 
 back part of its temporal plates with the sphenoidal 
 angles of the ossa parietalia : by the posterior edges of 
 the same plates and its spinous processes, it joins with the 
 squamous portions of the ossa temporum ; from its spi- 
 nous processes to the roots of the pterygoid processes it 
 touches slightly the inferior angles of the petrous por- 
 tions of the ossa temj)orum, and by its basilar process 
 with the sphenoidal process of the os occipitis : by the 
 anterior edges of its orbitar plates it joins with the ossa 
 malarum ; by the anterior surfaces of its pterygoid plates 
 with the ossa palati ; and by the processus azygos to the 
 vomer. 
 
 The muscles attached to the os sphenoides are thir- 
 teen pairs ; viz. the M. levator palpebrae superioris, 
 levator, depressor, abductor, adductor & obliquus su- 
 perior oculi, temporalis, pterygoideus externus & 
 
A DESCRIPTION OF THE BONES. 101 
 
 internus, buccinator, externus mallei, constrictor pha- 
 ryngis superior, & tensor palati. 
 
 CHAP. VI. 
 
 Of the Sutures and the Basis of the Skull. 
 
 The OS ethmoides and os sphenoides, with the os 
 frontis, ossa parietalia, os occipitis, and ossa temporum, 
 complete the cranium, and form by their union the large 
 cavity in which the brain and its membranes are placed, 
 and this is called the brain case, or skull. 
 
 The Skull is said to be of an ovate shape,* the nar- 
 rowest part being in front, and the broadest behind ; it 
 is arched symmetrically above from before to behind, and 
 from side to side ; and it is irregularly concave below. 
 Its anterior part, which is more or less perpendicular and 
 broad, is called the forehead, frons ; its upper part, 
 which is generally flat, the top of the head, vertex ; and 
 behind is the hind head, occiput; the sides of the head 
 are usually called the temples, tempora ; the boundaries 
 of which are, the temporal arches upon the frontal, 
 parietal, and temporal bones ; and the inferior surface 
 forming the floor of the skull is called the external base, 
 basis externa, which assists in forming several parts 
 hereafter to be described and considered as belonging to 
 the face. 
 
 • See page 70. 
 
102 A DESCRIPTION OF THE BONES. 
 
 THE SUTURES. Sjiturce. 
 
 The bones of the skull, by their union with each 
 other, form that sort of junction which is called suture, 
 resembling very nearly the stitches employed in joining 
 one piece of cloth to another ; it is a kind of digita- 
 tion or receiving of the small finger-like processes, formed 
 f3y the edge of one bone, into those of the other; and 
 the joint so produced is very strong but allows a slight 
 yielding. Of these sutures there are seven ; viz. the 
 
 CORONAL, SAGITTAL, LAMBDOIDAL, tWO SQUAMOUS, ETHMOI- 
 DAL, and SPHENOIDAL. 
 
 1. Sutura coronalis, so called from being situated at 
 that part of the head upon which the ancients were used 
 to place the laurel or olive crown, given to the victors in 
 their games. It commences about an inch behind the 
 external angular process of the os frontis, passes verti- 
 cally over, but rather inclining backwards, and descends 
 to terminate at the same point on the opposite side of 
 the skull. It joins the os frontis with the two ossa 
 parietalia. 
 
 2. Sutura sagittalis ; named from its straight course. 
 It commences from the middle of the highest part of 
 the coronal suture, runs directly backwards, and termi- 
 nates at the occipital angle of the os occipitis. This 
 termination is known in the living subject by continuing 
 round the head that horizontal line from which the 
 coronal suture takes its origin. It joins the two os^a 
 parietalia. The sagittal suture is occasionally continued 
 
 * No engraving of the Sutures is given, as with a skull before him, 
 and having learned the bones already described, the student can follow 
 them without difiBculty. 
 
A DESCRIPTION OF THE BONES. 103 
 
 down the os frontis to the nasal spine of that bone ; which 
 part of it is then called the frontal suture, 
 
 3. Sutura lamhdoidalis, receives its name from its 
 resemblance to the Greek A. It commences at the termi- 
 nation of the sagittal suture, and extends down into the 
 posterior part of the foramen lacerum basis cranii poste- 
 rius on each side. The situation of this suture may be 
 described, by carrying a line from the termination of the 
 sagittal suture downwards and outwards, immediately 
 behind the root of the mastoid process, on each side of 
 the skull. It joins the os occipitis with the ossa parietalia 
 above, and the partes mamillares of the ossa temporura 
 below. By some anatomists the junctions of the os 
 occipitis with the ossa temporum are called additamenta 
 suturcB lambdoidalis. In the lambdoidal suture, and not 
 unfrequently in the sagittal, are found several little bones, 
 which, from being of a triangular form, have been called 
 ossa triquetra ; they are not, however, to be considered 
 distinct bones, but merely loose pieces, which by accident 
 have not become ossified to the adjacent bone. 
 
 4 & 5. Suturce squamoscB. So named from the over- 
 lapping of the bones like fish scales. One on each side 
 commences about a quarter of an inch behind the lowest 
 part of the coronal suture, rises up a little, and, forming 
 part of an arch, descends and terminates in the lamb- 
 doidal suture, at the posterior superior point of the pars 
 mamillaris of the os temporis. It joins the os temporis 
 with the OS parietale. That part of the suture, which 
 connects the pars mamillaris of the os temporis with the 
 temporal angle of the os parietale, is sometimes called 
 additamentum sutures squamoscB ; the junction at this part 
 is denticulated rather than serrated, whilst the superior 
 
104 A DESCRIPTION OF THE BONES. 
 
 part of the suture is scaly, the edge of each bone being 
 bevelled off, in such way, that though one bone overlaps 
 the other, still there is no increase in the thickness of the 
 skull opposite the squamous suture. 
 
 6. Sutura ethmoidalis. This unites the cribriform 
 plate of the os ethmoides to the orbitar plates of the os 
 frontis. 
 
 7. Sutura sphenoidalis. This suture is very exten- 
 sive. It commences at the junction of the outer edge of 
 the spinous process of the os sphenoides, with the inner 
 edge of the glenoid cavity of the os temporis, passes a 
 little forwards and upwards, and then directly upwards to 
 the anterior part of the squamous suture, joining the 
 temporal plate of the os sphenoides wdth the anterior part 
 of the squamous portion of the os temporis; is then con- 
 tinued downwards and forwards, joining the upper edge 
 of the temporal plate of the os sphenoides with the sphe- 
 noidal angle of the os parietale, and that edge of the os 
 frontis which is found in the temporal fossa ; it passes 
 across the skull from the anterior point of the sphe- 
 noidal angle of one os parietale to the same part of the 
 other, and in its course joins the upper edges of the or- 
 bitar plates, the transverso-spinous and ethmoidal pro- 
 cesses of the OS sphenoides, with the orbitar plates of the 
 OS frontis, and the cribriform plate of the os ethmoides ; 
 and it is continued between the frontal, parietal, and tem- 
 poral bones above, and the sphenoid below, to terminate 
 at the inside of the glenoid cavity. 
 
 Some of the sutures are very important, as they de- 
 scribe the course of the vessels of the brain ; thus the 
 sagittal suture points out that of the longitudinal sinus ; 
 the anterior superior point of the squamous suture con- 
 
A DESCRIPTION OF THE BONES. 105 
 
 tains the middle artery of the dura mater ; the posterior 
 inferior point of the same suture denotes the passage of 
 the lateral sinus on each side ; and a horizontal line ex- 
 tended round the os occipitis, from that point of one to 
 the same point of the other suture, describes the course 
 of the same sinus along the inside of the os occipitis, and 
 defines the spot to which the tentorium is attached pos- 
 teriorly. And so if a line be continued from the posterior 
 termination of the sagittal suture to this line, and another 
 from the anterior point of the same suture, down to the 
 nasal process of the os frontis, the whole course of the 
 longitudinal sinus is completely described. These are 
 points which, though seemingly trivial in themselves, are, 
 as connected with surgical practice, of the highest im- 
 portance, and therefore particularly to be attended to. 
 
 In order to see the parts within the skull, it is neces- 
 sary to make a transverse section of the os frontis, ossa 
 parietalia, and os occipitis ; this should be commenced 
 about half an inch above the superciliary ridges, and car- 
 ried through the tops of the squamous sutures, through 
 the parietal angles and upper part of the occipitis. The 
 vault of the cranium, thus removed, is called the skull- 
 cap, caharia; and the lower part on which the brain rests, 
 the internal basis, basis interna. In the 
 
 CALVARIA, 
 
 The parts to be observed are the longitudinal groove, 
 sulcus longitudinalis (1,1,1), for the longitudinal sinus, 
 with a number of little pits (2, 2, 2, 2), more or less 
 deep, in which the glandulae pacchionao are situated : 
 there are also the impressiones digitatae (3, 3, 3, 3) and 
 eminentiae mamillares (4, 4, 4, 4), produced by the convo- 
 
lOG 
 
 A DESCRIPTION OF THE BONES. 
 
 lutions of the brain ; the groovings for the meningeal 
 arteries (5, 5), and the parietal holes (6, 6). 
 
 .5 
 
 BASTS INTERNA. 
 
 The internal basis is divided into three portions, the 
 
A DESCRIPTION OF THE BOXES. 
 
 107 
 
 anterior, or frontal (i) ; the middle, or sphenoido- tempo- 
 ral (ii); and the posterior, or occipital (iii). 
 
 1. Portia frontalis (i), is bounded before and to the 
 
 sides by the fronto-temporal portions of the os frontis 
 (a, a), and behind by the transverso-spinous processes 
 {b, b) of the OS sphenoides. It has in the middle, in front 
 the spine of the os frontis (1), to which the falx major of 
 the dura mater is attached ; at the root of which is the 
 foramen caecum (2) ; and behind it, the crista galli (3) ; 
 to both of which the falx is also attached ; on each side 
 of the crista galli is the cribriform plate of the os eth- 
 moides (4, 4) ; and further out, the orbitar plates of the 
 OS frontis (5, 5), upon which the anterior lobes of the ce- 
 rebrum rest. 
 
 The Foramina in this division are 
 
 Foramen ccecum (2), for the attachment of the dura 
 mater, and sometimes the passage of a vein. 
 
 Foramina cribrosa (4, 4), for the passage of the olfac- 
 tory "and ethmoidal nerves into the nose. 
 
108 A DESCRIPTION OF THE BONES. 
 
 .2. Port'io sphenoido-temporalis (ii), bounded before by 
 
 the transverso-spinous processes of the os sphenoides 
 (b, b) ; on the sides by the squamous portions of the 
 ossa temporum (c?, d)\ and behind by the superior angles 
 of the petrous portions (e, e) of the same bones, and the 
 posterior chnoid process of the os sphenoides (f). It 
 has in the middle, the sella turcica (6) for the lodgement 
 of the pituitary gland of the brain, bounded behind by the 
 posterior clinoid process (f) : and before, by the two ante- 
 rior clinoid processes (c, c) ; between which is the processus 
 olivaris (7), and upon it the optic nerves join : ex- 
 tending outwards from the anterior clinoid, are the 
 transverso-spinous processes (6, b) ; on each side of the 
 sella turcica, but below it, is a groove (8, 8) for the ca- 
 rotid artery, and the cavernous sinus, and below that a 
 shallow groove (9, 9) for the superior maxillary nerve ; 
 further out on each side, are the cavities (10, 10) to 
 
A DESCRIPTION OF THE BONES. 109 
 
 lodcre the middle lobes of the brain; behind, on the ante- 
 rior surfaces of the petrous portions of the ossa tem- 
 porum, are seen the juttings of the anterior legs of the 
 vertical semicircular canals (11, 11), the cSfnalis innomi- 
 natus for the nervits innominatus, (12, 12), and the com- 
 mencement of the superior petrosal sinuses (13, 13). 
 
 The Foramina in this division are 
 
 Foramina optica (14, 14), for the passage of the optic 
 nerves and ocular arteries into the orbits. 
 
 Foraminajacera orbitaria superiora (15, 15), for the 
 passage of the common oculo-muscular, inner oculo- 
 muscular, ophthalmic branch of the trigeminal, and outer 
 oculo-muscular nerves, out of the skull, and the return 
 of the ocular veins into it, to the cavernous sinus. 
 
 Foramina rotunda (16, 16), for the passage of the 
 superior maxillary branch of the trigeminal nerve to the 
 parts about the upper jaw. 
 
 Foramina ovalia (17, 17), for the passage of the in- 
 ferior maxillary branch of the trigeminal nerve to the 
 parts about the lower jaw. 
 
 Foramina carotica (18, 18), for the entrance of the 
 carotid arteries into the skull, and the passage of a branch 
 of the outer oculo-muscular nerve out of it. 
 
 Foramina spinosa (19, 19), for the entrance of the 
 middle artery of the dura mater. 
 
 Foramina lacera basis cranii anteriora (20, 20), filled 
 up by membrane, in the recent state, and giving passage 
 to the superficial branch of the pterygoid nerve. 
 
 Foramina innominata (21, 21), for the transmission of 
 the nervi innominati to the stylo-mastoid canals. 
 
110 
 
 A DESCRIPTION OF THE BONES. 
 
 3. Port'w occipitalis (iii), bounded before by the poste- 
 
 rior clinoid process of the sphenoid (f) and the superior 
 angles of the petrous portions of the ossa temporum (e, e), 
 and behind by the os occipitis (g, g). It has in the 
 middle, anteriorly, the basilar process (22), hollowed 
 out in the middle for the pons varolii, and medulla ob- 
 longata, and grooved at the edges (23, 23), where it joins 
 the petrous portions of the temporal bones for the in- 
 ferior petrosal sinuses : behind the basilar process is the 
 foramen magnum (24), extending up from the posterior 
 edge of which is the perpendicular ridge (25, 25), of the 
 OS occipitis crossed by the transverse ridge (26, 26), by 
 which the bone is divided into four cavities ; the two 
 upper (27, 27) for the posterior lobes of the cerebrum, 
 the two lower (28, 28) for those of the cerebellum ; the 
 superior angles of the petrous portions of the ossa tem- 
 porum and the transverse ridge of the os occipitis giving 
 attachment to the tentorium ; the former having each a 
 
A DESCRIPTION OF THE BONES. Ill 
 
 shallow groove (13, 13) for the superior petrosal sinuses, 
 and the latter a deep one for the lateral sinuses (29, 29), 
 which is continued dovvn into the temporal angles of the 
 OS occipitis ; the perpendicular ridge (25) giving attach- 
 ment above the transverse to the falx major, and grooved 
 for the longitudinal sinus (A), which terminates sometimes 
 in the left, and at other times in the right lateral sinus ; 
 the same ridge (25) below the transverse ridge giving 
 attachment to the falx minor, and shghtly grooved {i) 
 for the occipital sinuses. 
 
 The Foramina in this division are 
 
 Foramina auditiva interna (30, 30), for the passage 
 from the skull of the arteries of the labyrinth, the audi- 
 tory and facial nerves. 
 
 Aquceductus vestibulorum (31, 31), for the evacuation 
 of fluid from the vestibule. 
 
 Foramina lacera basis cranii posteriora (32, 32), for 
 the passage of the glosso-pharyngeal, pneumo-gastric, 
 and accessory nerves yVow the skull; and the junctions 
 of the lateral sinuses with the internal jugular veins. 
 
 Foramen magnum (24), for the passage of the medulla 
 oblongata and anterior arteries of the spinal marrowyVo?// 
 the skull, and the entrance of the vertebral arteries and 
 the accessory nerves into it. 
 
 Foramina condyloidea anteriora (33, 33), for the pas- 
 sage of the lingual nerves from the skull. 
 
 Foramina condijloidea posteriora (34, 34), for the en- 
 trance of veins into the occipital sinus, are seen in the 
 hinder edge of the foramina lacera posteriora (32, 32). 
 
 Foramina masioidea (35, 35), for the passage of a 
 vein into the lateral sinus : sometimes there is but one of 
 these. 
 
112 
 
 A DESCRIPTION OF THE BONES. 
 
 BASIS EXTERNA. 
 
 The external basis, like the internal, is also divided 
 into three portions, the anterior, or ethmoido-frontal (i) ; 
 
 the middle, or sphenoido-temporal (ii) ; and posterior, or 
 occipital (ill). 
 
 1. Portio ethmoido-frontalis (i), bounded before by the 
 superciliary ridges of the os frontis (rt, a), and behind 
 
A DESCRIPTION OF THE BONES. 113 
 
 by the roots of the pterygoid processes of the os sphe- 
 noides (6, b). It has anteriorly in the middle the nasal 
 spine (1), and process of the os frontis (2, 2), bounded 
 by the internal angular processes (3, 3) ; behind the spine 
 is the nasal plate of the os ethmoides (4) ; and behind it 
 the processus azygos of the sphenoid bone (5) : on each 
 side of the nasal plate of the ethmoid are the turbinated 
 plates (6, 6) and convolutions (7, 7) of the same bone, 
 bounded on the sides by its flat plates (8, 8) ; to their outer 
 side are the orbitar plates of the os frontis (9, 9) bounded 
 by its external angular processes before (10, 10), and by 
 the orbitar plates of the os sphenoides behind (11, 11); 
 and to their outer side the temporal plates of the same 
 bone (12, 12). 
 
 The Foramina in this division are ' 
 
 Foramina supra-orhitaria (13, 13), for the passage of 
 the supra-orbitary nerves and vessels to the forehead. 
 
 Foramina frontalia (21, 21), sometimes only one, for 
 the passage of a nerve into the frontal sinuses. 
 
 Foramina orbitaria interna, anteriora (22, 22), (^' pos- 
 teriora (23, 23), the former two, for the entrance of the 
 ethmoidal nerves into the skull ; the latter two, for the 
 passage of small arteries and nerves. 
 
 Foramina pterygoidea (25, 25), for the entrance of 
 the pterygoid nerves into the pterygoid canals. 
 
 Openings (26, 26) of the frontal and anterior eth- 
 moidal sinuses. 
 
 Openings (27, 27) of the posterior ethmoidal sinuses. 
 
 Openings (28, 28) of the sphenoidal sinuses. 
 
 The preceding are not seen in the internal basis ; the 
 following are, viz. : 
 
114 
 
 A DESCRIPTION OF THE BONES. 
 
 Foramina optica (14, 14). 
 
 Foramina laccra orbitaria snperiora{l5, 15). 
 
 Foramina rotunda (16, 16). 
 
 2. Portio sphenoido-temporalis (ii), bounded before by 
 
 s - 
 
 the roots of the pterygoid processes of the os sphenoides 
 (6, b), and the styloid processes of the ossa temporum 
 (c, c) behind. It has in the middle anteriorly, the body 
 of the OS splienoides (29); on either side of which, 
 are the pterygoid processes of the same bone (30, 30), 
 divided into two plates by the fossae pterygoideae (31, 31); 
 and to their outer side a flat space (36, 36) for the 
 origins of the M. pterygoidei externi ; behind the body 
 of the sphenoid is the basilar process (37), of the os occi- 
 pitis; on its sides, the anterior points of the petrous por- 
 tions (38, 38) of the ossa temporum ; further out the 
 spinous processes of the os sphenoides (39, 39), and to 
 their outside the glenoid cavities of the ossa temporum 
 (40, 40), bounded laterally, before by the roots of the 
 zygomatic processes (41, 41), and behind by the auditory 
 processes of the same bones (42, 42), 
 
 The Foramina in this division are 
 
 Foramina auditiva externa (43, 43), the beginning 
 of the external auditory passage. 
 
A DESCRIPTION OF THE BONES. 
 
 115 
 
 Foramina glenoidea (44, 44), for the passage of the 
 nervus chorda tympani and the tendon of the M. exter- 
 nus mallei. 
 
 Openings (45, 45) of the Eustachian tubes from the 
 tympanum to the throat. 
 
 Neither of the above are seen in the Internal Basis ; 
 but the following are, viz. 
 
 Foramina ovalia (17, 17). 
 
 Foramina carotica (18, 18). 
 
 Foramina spinosa (19, 19). 
 
 Foramina lacera basis cranii anteriora (20, 20). 
 
 3. Portio occipitalis (iii), bounded before by the sty- 
 loid processes of the ossa temporum (c, c), and behind by 
 
 the OS occipitis {d, d). It has in the middle, the foramen 
 magnum (24) ; to the fore part of which are the processus 
 condyloides (46, 46) ; on their outer side, a ridge for the 
 attachment of the M. recti laterales capitis (47, 47) : fur- 
 ther out, and rather before, the styloid processes (c, c) of 
 the ossa temporum, surrounded by their vaginal pro- 
 cesses (48, 48) : behind which, and rather more outward, 
 the^ mamillary processes (49, 49), having at their roots 
 
 I 2 
 
116 A DESCRIPTION OF THE BONES. 
 
 the digastric pits (50, 50) ; the os occipitis marked be- 
 hind the foramen magnum, by the inferior (51, 51) and 
 superior (52, 52) transverse arches, the spine, (53) pro- 
 tuberance (54), and pits (55, 55). 
 
 The Foramina in this division are 
 
 Foramina stylo-mastoidea (56, 56), for the passage 
 of the facial nerves from the stylo-mastoid canals. 
 
 The above are not seen on the inside ; but the fol- 
 lowing are. 
 
 Foramen magnum (24). 
 
 Foramina lacera basis cranii posteriora (32, 32). 
 
 Foramina condyloidea anteriora (33, 33). 
 
 Foramina condyloidea posteriora (34, 34). 
 
 Fora?nina mastoidea (35, 35). 
 
 CHAP. VII. 
 Of the Bones of the Face,^ 
 
 These consist of six pairs and two single bones. 
 
 CHEEK BONES. Ossa Malarum (1). 
 
 Situation. At the outer and under part of the orbit 
 and side of the face, forming tlie prominence of the 
 cheek. 
 
 Description. The os malae is of an irregular figure, 
 and divided into three faces and five processes. 
 
 * For their relative position, see page 71. 
 
A DESCRIPTION OF THE BONES. 
 
 117 
 
 1. Superficies malaris (1), in front and to the outer 
 side, irregularly convex from before to behind ; its ante- 
 rior inner edge bounded by the maxillary process, p. max- 
 illaris (2) ; its external posterior edge bounded by the 
 
 Anteiior surface. 
 
 Posterior surface. 
 
 zygomatic process, p. zygomaticus (3), and joining with 
 the malar process of the os temporis to form the zygoma, 
 under which the M. temporalis plays. 
 
 2. Superficies orbitaris (4), above forming the inter- 
 nal orbitar process, p. orbitaris internus (4), bounded 
 above and to the outer side by the p. orbitaris superior 
 (5), and below to the inside by the p. orbitaris inferior 
 (6) : on the internal orbitar process is seen a hole (7), 
 which is the commencement of the passage leading to the 
 malar hole. 
 
 3. Superjicies temporalis (8), situated behind, irre- 
 gularly concave, and completing the temporal pit, which 
 is therefore composed of five bones, viz. os temporis, 
 parietale, sphenoides, frontis, and malae. 
 
 There is but one Foramen in this bone : 
 Foramen malare (9), the beginning of which (7) is 
 seen in the orbitar surface (4), and its termination (9) on 
 the malar surface (1) : through it the malar nerve passes. 
 Junctions. The os malae is joined by its zygomatic 
 process to the malar process of the os temporis ; by its 
 superior orbitar process to the external angular process 
 
118 
 
 A DESCRIPTION OF THE BONES. 
 
 of the OS frontis ; by the posterior edge of its internal 
 orbitar process with the orbitar plate of the os sphe- 
 noides ; and by the inner edge of the same process and 
 the inferior orbitar process with the os maxillare superius. 
 The muscles attached to it are four ; viz., M. obliquiis 
 inferior oculi, zygomaticus major & minor, & masseter. 
 The M. orbicularis palpebrarum extends over it. 
 
 SUPERIOR MAXILLARY BONES, OR UPPER JAW. 
 
 Ossa Maxillaria Superiora (2). 
 
 Situation. In the front of the face, between the 
 cheek bones, forming a large part of the orbits, and the 
 fore part of the nostrils, face, and palate. 
 
 Description. The superior maxillary bone is divided 
 
 
 Internal Surface. 
 
 External Surjace. 
 
 into body and processes. The body (1) is of an irregular 
 figure and hollowed to form the maxillary sinus, antrum 
 highmorianum vel sinus maxillaris (26) ; its anterior sur- 
 face hollowed from above downwards, and from side to 
 side, forming the infra-orbitar pit, fossa infra-orbitaris 
 (2), in the upper part of which is the infra-orbitar hole, 
 
A DESCRIPTION OF THE BONES. 119 
 
 foramen infra-orbitare (3) : the body is bounded above 
 and to the outer side, anteriorly, by an irregularly denti- 
 culated process, extending as far as opposite the infra- 
 orbitar hole, called malar process, processus malaris (4), 
 which projects most below, and is hollowed behind, for the 
 play of the M. temporalis ; to the inner side and above, 
 springing up from the body, is the nasal process, pro- 
 cessus 7iasalis (5), of a pyramidal form, having in its 
 fore part a hole for an artery ; it is rough (C) above to 
 join with the os frontis, becomes prominent as it de- 
 scends, and has its inner edge (7) grooved to receive the 
 OS nasi; below which is a notch (8) where the alar carti- 
 lages of the nose are attached ; behind, and to the outer 
 side above, the nasal process is concave, to form part of 
 the lacrymal pit, fossa lacrymalis (9), in which the 
 lacrymal sack is placed ; and before it the bone is pinched 
 up so as to form a sharp ridge (lO), behind which the 
 concavity of the pit descends, becomes wider, and forms 
 part of the nasal duct, ductus ad nasum (11); between 
 the malar and the nasal processes extending backwards 
 is the orbitar plate, lamella orbitaris (12), of a trian- 
 gular figure, the base of which facing inwards joins 
 with the flat plate of the os ethmoides ; and at its in- 
 ner part is the lacrymal notch, incisura lacrymalis (13), 
 in which the os lacrymale is received : its posterior 
 edge (14) forms the lower part of the spheno-maxillary 
 fissure, and has in it the beginning of the infra-orbitar 
 canal, canalis infra-orbitar is (15), which runs along the 
 orbitar plate forwards, and when about half an inch dis- 
 tant from the anterior edge of the orbit, dips down to ter- 
 minate in the infra-orbitar hole (3) : the posterior surface 
 of the bone is rounded, and named the tuberosity, tuber 
 
120 A DESCRIPTION OF THE BONES. 
 
 maxillare (IG), the inner edge of which (17) is rough to 
 join with the pterygoid process of the os palati, and os 
 sphenoides, forming with them the palato-maxillary 
 canal and hole : from the inner and under part of the 
 body, extends horizontally inwards, the palatine process 
 processus palatinus (18), thin, about a finger's breadth, 
 hollowed above from side to side, forming the greater 
 part of the floor of the nose, and hollowed below to 
 form as much of the roof of the mouth ; it becomes 
 much deeper at its inner edge, and rough, to join with 
 its fellow, and form above the nasal crest, crista na- 
 salis (19,) which is grooved to receive the vomer, and 
 extending beyond the bony part of the nostrils, gives^ 
 attachment to the cartilaginous septum of the nose ; 
 below the junction forms the palatine spine, spina pala- 
 tina (20.) ; at the anterior part of the floor of the nostril, 
 close to the nasal crest, is the foramen incisivum (21), 
 leading to the ductus incisivus (22) ; and at the back 
 part, the palatine process is deeply notched, to receive 
 the OS palati : around the inferior, anterior, and external 
 part of the body are sent down two alveolar processes, 
 processus alveolares (23, 23), divided by alveolar plates, 
 lamellcB alveolares, into alveolar cavities, cavitates alve- 
 olares, of which there are usually eight in each bone, to 
 receive as many teeth : in the alveolar cavity of the 
 second molar tooth, there is usually a hole of communi- 
 cation with the antrum ; between the root of the inner 
 alveolar process and the palatine plate, is a groove (24), 
 along which the palatine artery and nerve pass to the 
 ductus incisivus, which is formed by the junction of a 
 notch in the anterior part of the palatine spine : above 
 the floor of the nostril, and from its outer edge, rises up 
 
A DESCRIPTION OF THE BONES. 121 
 
 the side of the body (25), forming the inner boundary of 
 the antrum (26), and the nasal process (5) ; in the former is 
 the maxillary hole, foramen waxillare (27), by which 
 the antrum communicates with the middle chamber of 
 the nose : and upon the latter, just above and before the 
 termination of the nasal duct, is a horizontal ridge (28), 
 to which the anterior extremity of the os turbinatum is 
 attached. 
 
 The Foramina in the os maxillare superius are four, 
 and one is formed by the junction of both bones. 
 
 Foramen infra-orhitare (3), for the exit of the infra- 
 orbitar nerve and vessels from the canal. 
 
 Foramen maxillare (27), from the antrum into the 
 nose. 
 
 Foramen incisivum (21), from the nostril into the 
 ductus incisivus, for the anastomosis of the spheno-pala- 
 tine, and palatine nerves and vessels. 
 
 The opening from the alveolar cavity of the second 
 molar tooth into the antrum. 
 
 Ductus incisivus (22), formed by the junction of both 
 the superior maxillary bones. 
 
 Besides these are found part of the ductus ad nasum 
 (11), of the fissura spheno-maxillaris (14), and the ante- 
 rior opening of the nostril (8). 
 
 Junctions. The os maxillare superius is connected 
 by its malar process with the inferior orbitar process of 
 the OS malae ; by the anterior inner edge of its nasal pro- 
 cess with the OS nasi ; and by the ridge on the inside of 
 that process with the os turbinatum ; by the upper part 
 of the same process with the nasal process of the os 
 frontis ; by the posterior part of the same process, and 
 its lacrymal notch with the os lacrymale ; by the inner 
 
122 A DESCRIPTION OF THE BONES. 
 
 edge of its orbitar plate with the flat plate of the os eth- 
 moides ; by the posterior point of the same plate with 
 the OS palati ; and by its tuberosity, body, and palatine 
 process to the same bone ; by the inner edge of its pala- 
 tine process with that of its fellow ; and by the nasal 
 crest formed by the junction of both bones with the 
 vomer. 
 
 The muscles attached to it are ten ; viz. M. con- 
 strictor pharyngis superior, pterygoideus externus, buc- 
 cinator, masseter, levator anguli oris, levator, & de- 
 pressor labii superioris alseque nasi, orbicularis palpe- 
 brarum, obliquus oculi inferior, & compressor naris. 
 
 NASAL BONES. Ossa Nasi (3). 
 
 Situation. Immediately under the nasal process of 
 the OS frontis, and between the nasal processes of the ossa 
 maxillaria superiora : these bones are of a small size, 
 narrow and thick above, thin and expanded below ; they 
 form the bridge of the nose. 
 
 Descrijotioji. The external surface of the os nasi (a) 
 is slightly concave from above down- 
 wards, and convex from before to 
 behind; after it has began to expand, 
 the internal surface {b) is thick above, 
 and concave from before to behind ; it 
 has four edges, the superior, margo 
 frontalis (1), thick and deeply denticulated, to join with 
 the nasal process and spine of the os frontis, and the 
 nasal plate of the os ethmoides ; its external edge, margo 
 maxillaris (2), grooved, and received into the nasal pro- 
 cess of the OS maxillare superius ; its inner edge, margo 
 
 1 
 
A DESCRIPTION OF THE BONES. 123 
 
 nasalis (3), flat, to join with its fellow; and its lower 
 edge, margo alaris (4), thin and irregular, to join with 
 the alar cartilages of the nose. 
 
 The muscles attached to it are two ; viz. M. occipito- 
 frontalis, & compressor naris. 
 
 LACRYMAL BONES. Ossa Lacnjmalia (4). 
 
 Situation. The os lacrymale is placed at the fore 
 and inner part of the orbit behind the nasal process of 
 the OS maxillare superius ; and before the flat plate of 
 the OS ethmoides ; it is of an oblong square shape, and 
 very thin. 
 
 Description. Internally (a) it is hollow, and covers 
 a f, the anterior ethmoidal sinuses, forming the 
 
 ethmoidal plate, lamella ethmoidalis (1) ; 
 externally (6) it is divided by a perpendicu- 
 lar ridge (2), which terminates below in a 
 little hook-like process (3) into tw^o un- 
 equal plates, the posterior, of which the flattest, shortest, 
 and broadest, is called the orbitar plate, lamella orbi- 
 taris (4) ; and the anterior, the lacrymal plate, lamella 
 lacrymalis (5), is the most concave and narrow^ but the 
 longest. 
 
 Junctions. The os lacrymale is joined above to the 
 internal angular and orbitar plates of the os frontis ; 
 behind, to the flat plate of the os ethmoides ; below, to 
 the orbitar plate of the os maxillare superius ; before, to 
 the nasal process of the same bone; and before and 
 below, to the os turbinatum. 
 
124 
 
 A DESCRIPTION OF THE BONES. 
 
 Jnterior Surface. 
 
 PALATINE BONES. Ossa Palatina (5). 
 
 Situation. At the under, outer, and back part of the 
 nostrils, between the ossa maxillaria superiora before, 
 and the pterygoid processes of the os sphenoides behind : 
 they are of a very irregular figure. 
 
 Description. The os palati is divided into palatine, 
 nasal, pterygoid, orbitar, and sphenoidal processes : the 
 processus palaiinus (1), like that of the su- 
 perior maxillary bone, is deepest on its 
 inner edge, where it joins with its fellow, 
 to complete the back part of the nasal 
 crest above (a), and the palatine spine 
 below (h) ; it projects back, forming a 
 little spinous process (2), to which a muscle 
 is attached ; from the outer edge of the 
 palatine rises up the nasal process, p, na- 
 salis (3), forming part of the walls of the 
 sinus maxillaris, and marked internally by 
 a strong ridge (4), to which the os tur- 
 binatum is attached; behind the nasal 
 Posterior Surface, proccss, aud facing backwards, and 
 rather outwards, is the pterygoid process, 
 p. p>terygoideus (5), having two grooves 
 (6, 6) in it, to receive the pterygoid pro- 
 cesses of the OS sphenoides, and a middle 
 ridge (7) which enters into the fissura pte- 
 rygo-palatina of that bone ; anteriorly this 
 process is rough (8), where it joins with 
 the tuberosity of the os maxillare supe- 
 rius and grooved where forming with it 
 the palato-maxillary canal, canalis palato- 
 Inferior Surface, maxillaris (9), terminating below in the 
 
 Internal Surface. 
 
A DESCRIPTION OF THE BONES lg5 
 
 palato-maxillary hole, foramen palato-maxillare (10), 
 through which the palatine nerve and vessels pass to the 
 palate ; sometimes, indeed generally, there is another 
 small hole behind, which is then called palatine hole, 
 foramen palatinum (11), to transmit branches of the same 
 vessels and nerve to the soft palate ; above the nasal 
 process, the bone springs out into two processes, divided 
 by a notch (12), the anterior is the orbitar process, p. orhi- 
 taris (13), of a triangular shape, and received between 
 the flat plate of the os ethmoides, and the orbitar plate 
 of the OS maxillare superius, to the inner and fore part, 
 and the root of the pterygoid process of the os sphe- 
 noides behind, forming a covering to part of the ethmoidal 
 sinuses ; the posterior process is the sphenoidal process, 
 'processus sphenoidalis (14), which joins to the anterior 
 inferior part of the body of the os sphenoides : the notch 
 between the two processes forms the lower part of the 
 spheno-palatine hole, foramen spheno-palathmm (12), the 
 remainder of which is formed by the os sphenoides. 
 
 The Foramina in this bone are two perfect and 
 one imperfect. The two perfect are 
 
 Foramen p>alato-maxillare {\0), formed by the junc- 
 tion of the palatine with the pterygoid process for the 
 passage of the palatine vessels and nerves. 
 
 Foramen imlat'inum (11), for the passage of branches 
 of the same nerve and vessels. The imperfect one is 
 
 Foramen spheno-palatinum (12), formed in part by 
 the OS palati, and in part by the os sphenoides, for the 
 passage of the spheno-palatine nerve into the nose. 
 
 Junctions. The os palati joins to its fellow by the 
 palatine process ; and by their nasal crest to the vomer : 
 by the anterior part of the palatine process to the same 
 
126 A DESCRIPTION OF THE BONES. 
 
 process of the os maxillare superius ; by tlie ridge on the 
 inside of tlie nasal process to the os turbinatum ; by the 
 nasal and pterygoid processes to the body and tuberosity 
 of the OS maxillare superius ; by its pterygoid, sphenoi- 
 dal, and orbitar processes to the pterygoid processes and 
 body of the os sphenoides ; and by its orbitar process to 
 the same process of the os maxillare superius, and the 
 flat plate of the os ethmoides. 
 
 The muscles attached to and connected with the os pa- 
 lati, are five ; viz. M. buccinator, pterygoideus externus & 
 internus, constrictor pharyngis superior, & azygos uvulae. 
 
 TURBINATED BONES. Ossa Turhinata. 
 
 Situation. On the outer sides of the cavities of the 
 nostrils. 
 
 Description. The os turbinatum is composed of two 
 unequal concave plates, joined together above, with their 
 concavities facing towards each other ; the outer plate (1), 
 the narrowest, and joined to the body 
 of OS maxillare superius, forming part 
 of the inner wall of the maxillary sinus ; 
 the inner plate (2) the broadest, and 
 depending into the nose ; its anterior 
 edge (3) slightly concave, and attached 
 to the ridge on the nasal process of the 
 OS maxillare superius, just touching the 
 lacrymal plate of the os lacrymale, to complete the nasal 
 duct ; its posterior extremity (4) very acute, and attached 
 to the ridge on the nasal process of the os palati. 
 
 Junctions. Above and to the outer side, with the 
 body of the os maxillare superius ; anteriorly, to the 
 nasal process of the same bone, and to the os lacrymale ; 
 and posteriorly, to the nasal process of the os palati. 
 
A DESCRIPTION OF THE BONES. 
 
 IZ 
 
 PLOUGHSHARE BONE. Vomer. 
 
 Situation. Between the cavities of the nose. 
 Description. The vomer is said to resemble a 
 ploughshare. It is divided into fom' edges, the supe- 
 rior, or sj-jhenoidal (1), the broadest, 
 hollowed to receive the processus 
 azvgos of the os sphenoides ; the 
 anterior, or nasal (2), grooved to 
 receive the nasal plate of the os 
 ethmoides, and the cartilaginous 
 septmii of the nose ; the inferior, or crista! (3) thin, to 
 join with the nasal crest of the ossa maxillaria superiora 
 and palatina ; and the posterior, or jjIiarTjngeal (4), con- 
 cave, and facing towards the pharynx. 
 
 LOWER JAW. Os Maxillare Inferius. 
 
 Situation. Below all the other bones of the head, 
 and forming the lower boundary of the face. 
 
 Description. The lower jaw is of a semi-ellip- 
 tical form : it is divided into horizontal and ascending 
 
 branches. The ho- 
 rizontal branches, 
 rami horizontaIes{l), 
 form the lower part 
 of the bone, and to- 
 gether produce a 
 semi-ellipsis, which 
 is usually less than 
 
 External Surface. the UppCr jaW, SO 
 
 as to be received within it : when, however, the lower 
 jaw extends beyond the upper, the jaw is said to be under- 
 
128 
 
 A DESCRIPTION OF THE BONES. 
 
 Internal Surfnce. 
 
 hung : the diameter of the semi- ellipsis being behind, 
 
 its points form the 
 angles, anguVi (3) ; 
 extending forwards 
 from which are the 
 sides (4) of the jaw : 
 the front, instead of 
 being elliptical, is 
 flattened from side 
 to side, rather pro- 
 duced below, and 
 called the chin, sym- 
 physis (5) ; at the parts where the symphysis and rami 
 join, are seen the mental holes, foramina mentalia (G); 
 the sides and chin are about two fingers deep, and termi- 
 nated above by the jDrocessus alveolar es (7, 7), divided 
 by lamellce alveolares, into cavitates alveolares, of which 
 there are sixteen ; the under edges of the rami (8, 8) are 
 gibbous or thick, and rounded; within, the symphysis 
 and rami horizontals form a similar curve ; at the back 
 of the symphysis is seen the mental spine, sjmia mentalis 
 (9), which is sometimes bifid ; and extending along the 
 rami, is seen on either side, as far as the last dens mola- 
 ris, a sharp line (10, 10) for the attachment of the M. 
 mylo-hyoideus ; behind this the line becomes more 
 obtuse, and gives attachment to the M. buccinator. The 
 ascending branches, rami ascendentes (2), rise up from 
 the angles, and produce obtuse angles with the horizontal 
 branches ; they are broad from before to behind, pass 
 upwards, and terminate in a narrow neck, cervix (11); 
 on each side above which are tlie condyloid processes, 
 p. condyloides (12), convex and narrow from before to 
 
A DESCRIPTION OF THE BONES. 129 
 
 behind, broad and slig;htlv convex from side to side : 
 before the neck is a sharp concavity (13), into which the 
 M. pterygoideus externus is inserted ; this is bounded 
 anteriorly by the coronoid process, p. coronoides (14), 
 which is angidar, it passes down a little way sharp in 
 front, and then divides into two legs, which are lost, 
 one on the alveolar process, and the other on the side of 
 the jaw ; about an inch below the middle of the con- 
 cavity, between the condyloid and coronoid processes, 
 on the inside, are the inferior maxillary holes, foramina 
 maxillar'm inferiora (15), having a spinous process, p. 
 ■spinosus (IG), at the inner edge of each, for the attach- 
 ment of a ligament; and from below this a furrow (17), 
 runs downwards and forwards, in which a nerve rests. 
 Between the inferior maxillary and mental holes, a canal, 
 the infra-maxillary canal, canal'is infra-maxlllaris, runs 
 within the bone, under the alveolar cavities for the lodge- 
 ment of the dental nerve and vessels. 
 
 The Foramina in this bone are two pairs. 
 
 Foramina maxillaria inferiora (15), through which the 
 dental arteries and nerves enter the canal ; and the 
 
 Foramina mentalia (6), by which they pass out. 
 
 Junction. By capsular and lateral ligaments with the 
 glenoid cavities of the ossa temporum, having an inter- 
 articular cartilage between them. 
 
 The muscles attached to the os maxillare inferius are 
 thirteen pairs ; viz. externally M. masseteres, depressores 
 anguli oris, depressores & levatores labii inferioris ; in- 
 ternally M. temporales, pterygoidei externi 8c interni, 
 buccinatores, constrictores pharyngis medii, mylo-hj-oidei, 
 genio-hyoidei, digastrici, & genio-hyo-glassi. The M. 
 platysma myoides passes over it. 
 
 K 
 
130 
 
 A DESCRIPTION OF THE BONES. 
 
 CHAP VIII. 
 
 Of the Orbits f Nostrils, Palate, and Ears. 
 
 Besides the braincase and auditory passages, the bones 
 of the head form the cavities of the orbits, nostrils, palate, 
 and ears. 
 
 1. THE ORBITS, Orhitce, 
 
 Are two in number, and contain the organs of vision 
 with their appendages. 
 
 Situation. In the upper part of the face, above the 
 cheeks, on either side of the nostrils, and immediately 
 beneath the frontal bone. 
 
 They are irregularly conical cavities, having their 
 bases facing forwards and outwards, and their apices 
 inwards and backwards. 
 
 They are formed by three single bones, viz. 
 
 Os frontis (i), os ethmoides (ii), and os sphenoides 
 (III) ; and four pairs, viz. 
 
 Ossa maxillaria superiora (iv, iv), ossa palati (v, v), 
 ossa lacrymalia (vi, vi), and ossa malag (vii, vii). Each 
 orbit, therefore, is formed of seven bones, but both orbits 
 are composed of only eleven bones. 
 
 
 ri,iiiN>^v^^ 
 
 OulcT Side. 
 
 Iiintr Side. 
 
A DESCRIPTION OF THE BONES. 
 
 131 
 
 The processes of these several bones are thus 
 situated. The orbitar process (1) of the frontal bone is 
 placed above, and forms the entire vault of the orbit. 
 On the inner side anteriorly is the nasal process (2) of 
 the superior maxillary bone, behind which are the lacry- 
 mal and orbitar plates (3, 8) of the lacrymal bone, and 
 posterior to it the flat plate of the ethmoid (4). In the 
 back of the orbit is the outer part of the body of the 
 sphenoid bone (5). On the outer side at the fore part 
 is the orbitar plate (6) of the malar bone, and behind 
 it the orbitar plate (7) of the sphenoid. Below, in front, 
 is the inferior orbitar process (8') of the malar bone, and 
 behind it, forming the greater part of the floor of the 
 orbit, the orbitar plate (9) of the superior maxillary bone. 
 The Foramina in the orbits are ten pairs. 
 1. Tlie large openings of the orbits (10) to which the 
 eyelids are attached, composed of the superciliary ridge 
 
 {a) of the frontal bone above, 
 the margin of the malar bone 
 (6), from its superior to its inferior 
 orbitar process inclusive below, 
 and the nasal process (2) of the 
 superior maxillary bone. 
 
 2. The siq^erior orifices of 
 the nasal ducts (11) placed im- 
 mediately behind the nasal process (2) of the superior 
 maxillary bone, and formed by it and the lacrymal 
 plate (3) of the lacrymal bone. 
 
 3. Foramina frontalia (12). 
 
 4. ethmoidea interna anteriora (13). 
 
 5. ethmoidea interna posteriora (14). 
 
 6. 
 
 lacera orbitaria superiora (15). 
 K 2 
 
1 'lO 
 
 A DESCRIPTION OF THE BONES. 
 
 7. Foramina laccra orb'itar'ia inferiora (16), sen 
 
 Jissura' sphcno-maxillares. 
 
 8. ojjtica (17). 
 
 9. supra-orhitaria (1 8). 
 
 1 0. The posterior openings of the infra-orhitar canals 
 (19), whicli commencing opposite the middle of the in- 
 ferior lacerated holes, rmi forwards beneath the orbitar 
 plate of the superior maxillary bone, to terminate at the 
 infra-orbitar hole on the cheek. 
 
 2. THE NOSTRILS, Cava Nasalia, 
 Are double, consisting of fourteen bones, viz. four 
 single, viz. 
 
 Os frontis (i) ; os ethmoides (ii); os sphenoides (iii) ; 
 and vomer (iv) ; and Jive pairs, viz. 
 
 Ossa nasi (v v) ; ossa lacrymalia (vi vi) ; ossa max- 
 illaria superiora (vii vii) ; ossa palatina (viii viii) ; and 
 ossa turbinata (ix).* 
 
 The anterior boundary of the nostrils is formed 
 
 Antcrxor bunndarv. Posterior boundary. 
 
 * It is well to observe that in order to save the multiplication of cuts, 
 reference to several of the engravings not in the immediate neighbourhood 
 of the descriptive part is necessary. 
 
A DESCRIPTION OF THE BONES. 
 
 133 
 
 above by the nasal (1) and inner angular processes (2, 2) 
 of the frontal bone, the nasal processes (3, 3) of the 
 superior maxillary bones, and the nasal bones (v v) ; and 
 on the sides by the notches (4, 4), and below by the 
 palatine processes (5, o) of the superior maxillary bones. 
 The iiosterwr boundary is formed above by the body 
 (6) of the sphenoid bone, on the sides by the nasal plates 
 (7, 7) of the same bone, and below by the palatine pro- 
 cesses (8, 8) of the palate bone. 
 
 The lateral boundaries consist below, of the bodies 
 
 (9, 9) of the superior maxil- 
 lary bones in front, and the 
 nasal processes (10, 10) of the 
 palate bones and the nasal 
 plates (7, 7) of the sphenoid 
 bone behind, and the insides of 
 .26 the orbits (11, 11) above. 
 
 The superior boundary, 
 _ or roof, is formed by the 
 
 LaJl^^ou^XT^^ n-'^sal (1) and inner angular 
 (2, 2) processes of the frontal bone, and the cribriform 
 plates (12, 12) of the ethmoid before, and by the body 
 (6) of the sphenoid bone behind. 
 
 The inferior boundary, or floor, consists of the pala- 
 tine processes (5, 5) of the superior maxillary bonel^in 
 front, and the palatine processes (8, 8) of the palate 
 bones behind. 
 
 The two nostrils are separated by an imperfect parti- 
 tion, septum, which, in the recent state, is completed by 
 cartilage. It consists of the nasal plate (13) of the eth- 
 moid bone, which joins above and before with the nasal 
 process (1) of the frontal bone, and behind with the body 
 
134 
 
 A DESCRIPTION OF THE BONES. 
 
 (6) of the sphenoid bone; both these bones join be- 
 hind and below with the 
 vomer (iv), which is 
 connected by its lower 
 edge with nearly the 
 whole length of the nasal 
 crest (15, 15) of the su- 
 perior maxillary and 
 palate bones. 
 
 Into the cavities of 
 the nostrils depend, at 
 ^pa,tiiionof\ostriis. the Upper part the con- 
 
 volutions (16, 16) of the ethmoid bone, including its 
 19 10 turbinated plates (17, 
 
 17), and towards the 
 lower parts of the side 
 walls the turbinated 
 bones, (ix, ix) are at- 
 tached from the hook- 
 like process (18) of the 
 lacrymal bone, along the 
 superior maxillary and 
 palate bones as far back 
 as the nasal plates (7, 7) 
 ■"of the sphenoid. By the jutting of the turbinated plates 
 of the ethmoid, and turbinated bones, each nostril is sub- 
 divided into three irregular cavities or chambers, meatus. 
 The superior chamber, meatus superior (a), includes 
 the space between the cribriform plate (12) of the eth- 
 moid above, and the lower edge of its turbinated plate 
 (17) below. In it are 
 
 The openings of the cribrous holes (19, 19), of the 
 
 "Vransverse vertical section of Orbits, 
 Nostrils, and Palate. 
 
A DESCRIPTION OF THE BONES. 135 
 
 posterior ethmoidal (20), and of the sphenoidal sinus 
 (21), divided from its fellow by a bony plate (14). 
 
 The middle chamber, meatus med'ius (b), is the space 
 contained between the turbinated plate (17) of the eth- 
 moid above, and the turbinated bone (ix) below. In it are 
 
 The openings of the frontal (22), anterior ethmoidal 
 (23), and maxillary sinus (24), and the spheno-palatine 
 hole (25). 
 
 The inferior chamber, meatus inferior (c), is bounded 
 above by the turbinated bone (ix), and below by the 
 floor (5, 8) of the nostrils. In it, immediately below the 
 junction of the turbinated with the lacrymal bones, is 
 
 The opening of the nasal duct (26'), and that of the 
 ductus incisivus (27). 
 
 With all three chambers are connected 
 
 The anterior (28, 28) and posterior (29, 29) openings 
 of the nostrils. 
 
 3. THE PALATE. Fornix Palat 
 
 inus. 
 
 The bony structure of the palate consists of t7vo pairs 
 of bones and a single one, viz. 
 
 Ossa maxillaria superiora (i, i) ; ossa palatina (ii, ii) ; 
 
 and ossa sphenoides (iii). 
 
 The margin is formed by 
 (' the alveolar processes (1, 1) of 
 ^ the superior maxillary bones, 
 before and on the sides, and by 
 the tips of the nasal plates (iii, 
 III) of the sphenoid behind ; 
 the arch of the palate by the palatine processes (2, 2) of 
 the superior maxillary bones, and by the palatine pro- 
 
1.56 
 
 A DESCRIPTION OF THE BONES. 
 
 cesses (3, 3) of the palate bones. In it are seen five 
 holes, viz. one single and two pairs. 
 
 The opening of the ductus incislvus (5), at the fore 
 part. And behind, close to the alveolar processes, the 
 
 2. Foramina palato-maxillaria (6, 6), and 
 
 3. palatina (7, 7). 
 
 4. THE EAR, Aims Interna. 
 
 The bony part of the organ of hearing is principally- 
 contained in the petrous portion of the temporal bone, 
 which is more fully developed at a very early period than 
 either of the other portions ; the evolution of which does 
 not seem actually necessary, as not being perfected till 
 the approach of manhood, and, even then, their existence 
 seems to be rather supplementary than absolutely ne- 
 cessary. 
 
 The internal ear, as it is commonly called, consists 
 of two parts : the drum, tympanum (i), with its canals, 
 by which it is connected with the auricle and throat ; and 
 
 liilative situation of Tympanum and Labyrinth. 
 
 The above engraving is copied from Soemmering. 
 
A DESCRIPTION OF THE BONES. 
 
 137 
 
 the labyrinth, labyrinthus (ii), in which the nervous 
 apparatus, in other words, the true auditory organ, is 
 expanded, and by which it is protected. 
 
 The Drum. Tympanum (I). 
 
 The drum of the ear is placed on the under part of 
 the petrous portion, at the bottom of a canal called the 
 external auditory passage, meatus auditorius externus (1), 
 commencing at the external auditory hole (2), and pass- 
 ing inwards and forwards about half an inch, till it meets 
 with a ridge of bone (3) containing a groove, where it 
 terminates. This ridge inclines outwards and backwards 
 at its upper and hinder part, so that the passage is of 
 greater length before and below, than behind and above. 
 The membrane of the drum, which is received within 
 the groove, consequently inclines downwards and inwards.^ 
 
 External section. 
 
 Internal section. 
 
 The drum is situated to the inner side of this ridge, 
 and opposite to it, nearly in a parallel plane ; is bounded 
 by an irregular plate of bone (6), which separates it from 
 the labyrinth : above it is protected by a thin plate of 
 bone (6'), part of the anterior surface of the petrous por- 
 tion, and below it is bounded by the top of the jugular 
 pit (4) and carotid canal (5) : it is of an oval form, and 
 
138 A DESCRIPTION OF THE BONES. 
 
 its greatest width, from within to without, is about 
 
 three lines. Three projec- 
 tions are seen in it : one 
 in the middle, upon the 
 inner plate, called the pro- 
 montory, i^^omontor'ium (6j, 
 which resembles a hillock, 
 surrounded by a deep ir- 
 regularly circular trench. 
 
 Internal section of liimpanam magnified. SlllUS tympani (7), aboVC the 
 
 upper part of which is seen the second, viz. the projection 
 of the commencement of the stylo-mastoid canal (8), here 
 distinctly exhibiting itself in the upper and back part of 
 the drum : the third is the pyramid, eminentia pyramida^ 
 lis (9), a minute eminence, standing forwards just below 
 the point where the stylo-mastoid canal begins to dis- 
 appear from the drum. 
 
 Nine principal apertures are found in the drum : 
 
 1. The large aperture (10) leading to the external 
 auditory passage. 
 
 2. The vestibular hole. Fenestra ovalis (11), above 
 the promontory, between it and the projection of the 
 stylo-mastoid canal, and leading into the vestibule. 
 
 3. The cochlear hole, Fenestra rotunda (12), below 
 the promontory, on its under part, and so overlapped by 
 it as to be easily overlooked ; this leads to the cochlea. 
 
 4. The aperture in the top of the pyramid (13), 
 through which the tendon of the M. stapedius passes. 
 
 5. A very small hole, apertura chordce (14), which 
 runs into the stylo-mastoid canal behind and opposite the 
 pyramid, and allows the passage of the Nervus chorda tym- 
 pani into the drum, having traversed which, it quits by 
 
A DESCRIPTION OF THE BONES. 139 
 
 6. The glenoid hole, foramen glenoideum (15), at the 
 fore and upper part. 
 
 7. The opening of the Eustachian tube, tuba Eusta- 
 chiana (16), large enough to admit the head of a probe, 
 is situated at the inner and under part of the drum, and 
 is the commencement of a canal, which gradually expands 
 as it passes inwards to terminate before the foramen 
 lacerum basis cranii anterius, in its cartilaginous part 
 which opens into the throat. 
 
 8. The opening by which the M, tensor tympani 
 enters the drum (17), is placed immediately before the 
 front end of the vestibular hole, and is the termination of 
 a bony canal running above the Eustachian tube, in 
 which the muscle just named is contained. 
 
 9. The large opening to the mastoidal cells (18), 
 above the pyramid, and passing over the projection of 
 the stylo-mastoid canal. 
 
 Contained in the cavity of the drum, are the four small 
 « Jl_ bones, ossicida auditus, viz. the 
 
 ^C ^ A hammer (a), anvil (ft), lenticular 
 (c), and stirrup (d) bones. 
 The hammer bone, malleus (a), has some resemblance 
 to the thigh bone deprived of its condyles ; 
 it has a rounded head (1), a smooth, arti- 
 cular surface, connected by a short neck 
 (2) to the shaft of the bone which, form- 
 ing the short process, j^rocessus brevis 
 (3), corresponds to the great trochanter : 
 passing down from this, and tapering towards its tip, 
 which curves slightly forwards, is the remainder of the 
 shaft, which is called the handle, manubrium (4), and, 
 from the front of the neck, curves forwards and down- 
 
140 
 
 A DESCRIPTION OF THE BONES. 
 
 wards, the longest but most delicate process, which is of 
 a flattened shape, and called the slender process, pro- 
 cessus gracilis (5) ; this is very commonly broken short 
 off at its root, and therefore not often seen. 
 
 The anvil bone, incus (h), has great similarity to a 
 double fanged grinding tooth; its head(l), 
 which faces outwards, is hollowed to receive 
 the head of the hammer bone ; it has two 
 processes : the short process, 2^rocessus brevis 
 (2), runs horizontally inwards from the head ; 
 and the long process, processus longus (3), descends 
 nearly vertically, is of lighter form than the former, and 
 its tip curves slightly inwards, receiving upon it. 
 
 The lenze bone, os lenticulare seu rotundum (c), which 
 is the smallest bone in the body, not exceeding the size of a 
 © f/ small pin's head, and often described as part of the 
 anvil bone, with which it becomes anchylosed at an early 
 period. Its shape resembles a lenze, whence its name. 
 The stirrup bone, stapes (d), rests on its side ; a little 
 projection on its outer end, hollowed to 
 receive the lenze bone, is called the 
 3 -g head (1), from which curve inwards 
 
 two slender processes (2, 2), connected at their points by 
 
 the base (3). 
 
 These four bones are con- 
 nected together, forming a chain, 
 which brinirs the membrane of the 
 drum into connection with that of 
 the vestibular hole, the hammer 
 bone being attached by its handle 
 to the tympanal, and the stapes 
 by its base to the vestibular 
 membrane. 
 
A DESCRIPTION OF THE BONES. 
 
 141 
 
 The Labyrinth. Labyrinthus. (II). 
 The labyrinth is placed behind and to the inner side 
 of the drum, in the most solid part of the petrous por- 
 
 VIEVVS OF LABYRINTH. 
 
 Posterior . 
 
 Anttrior. 
 
 Inferio y. 
 
 tion, and consists of three pieces : the vestibule (a), the 
 semi-circular canals (b), and the cochlea (c). 
 
 The vestibule, vestibulum (a), is placed posteriorly 
 and to the inner side of the drum, and immediately 
 behind the fenestra ovalis (11); within, before, and be- 
 low, it is bounded by the cochlea, and above and behind 
 by the semicircular canals : its size is about that of a 
 grain of wheat, and it has in it several apertures ; on 
 the fore and outer part is the vestibular hole (11), on the 
 outer and back part are the five openings of the semi- 
 vaticai Section. circular canals (19); on 
 
 the inner part, directly 
 opposite the fenestra, the 
 opening (20) by which the 
 auditory nerve enters the 
 vestibule ; on the fore and 
 under part is a hole lead- 
 
 Internal Surface. i^g tO tllC COChlca (21); 
 
 and at the posterior and inner part, near the common 
 orifice of the vertical and oblique semicircular canals, is 
 the orifice of the aqueduct, aquceductus vestibuli (22), 
 
 * All the succeeding Engravings, except the last, are copied from 
 Soemmering. 
 
 Posterior, 
 
142 
 
 A DESCRIPTION OF THE BONES. 
 
 which passes to terminate on the posterior surface of 
 the petrous portion. 
 
 The semicircular canals, canalcs semicircularcs (b), of 
 which there are three, are situated above and to the outer 
 side of the vestibule, and immedi- 
 ately behind tlie tympanum ; they 
 are three in number ; their name 
 V| implies their form, and their extre- 
 'i|' mities swelling out, each like a flask, 
 have been thence called ampidlce (d). 
 They are named from their position 
 vertical or superior (23), oblique or 
 
 Antei'ior J'ieu:. 
 
 Seition of Canals. 
 
 posterior (24), and horizontal or inferior (25) ; and each 
 leg opens by a distinct aperture into 
 the vestibule, except the posterior 
 leg of the vertical, and the superior 
 of the oblique, which terminate in a 
 common orifice, so that there are 
 but five apertures from them in the 
 
 Anteriov internal Surface. VeStlDUJC. 
 
 Tiie OS temporis consists only of two portions, which 
 are separate, viz. the squamous and petrous ; the mamil- 
 lary portion not being formed till some years after birth. 
 
 The cochlea (c) is placed immediately to the inner 
 
 fc^-^ 
 
 Base. 
 
 Apex. 
 
 side of the promontory and vestibule ; its form resembles 
 
A DESCRIPTION OF THE BONES. 
 
 143 
 
 Anterior interjinl surface 
 of spiral tube ; 
 
 that of a snail shell, its base (35) facing backwards and 
 upwards forms the bottom of the internal auditory passage, 
 its apex (24) depending forwards rests against the back 
 of the beginning of the Eustachian tube ; it is composed 
 of a central pillar of a conical form, 
 called the modiolus (26), and two and 
 a half turns of a spiral tube (27) 
 wound around it, the apex of which 
 forming the apex of the cochlea is 
 called the cupola (28). This spiral 
 
 the lamina spiralis removed. tubC Is ImpCrfcCtly divldcd iutO tWO 
 
 passages called scalce, by a thin plate of bone called Z«- 
 Lamina spiralis ; minu Spiralis (29), wliich, commcucing 
 
 from the promontory, makes two and a 
 half turns around the modiolus, and 
 terminates in a hook-like tip, called the 
 hook, hamulus (30), which is received 
 into a funnel-like process, called the 
 mfundihulum (31), projecting into 
 the cochlea from the inside of the cupola ; the upper of 
 these passages is called the scala 
 vestibuli (32), commencing from the 
 hole at the upper inner part of the 
 vestibule, and having made its turns, 
 reaches the hamulus and infundibu- 
 lum where it terminates in the lower 
 passage, the scala tympani (33), 
 which, in like manner, makes its turns 
 and terminates at the fenestra rotunda. The whole 
 of these passages are freely pierced by numerous holes 
 for nerves which have already perforated the cribri- 
 form base (35) of the modiolus. Besides these, close 
 
 the external shell of the 
 cochlea removed. 
 
 Horizontal section 
 
 thrnvzh tube, lamina, mnd'olus 
 and mtatus inttrnus. 
 
144 A DESCRIPTION OF THE BONES. 
 
 to the termination of the scala tympani, immediately 
 
 in front of the fenestra rotunda, is another opening, 
 
 that of the aqucuductus cochlecB (84), which terminates in 
 
 the jugular pit, on the under part of the petrous portion. 
 
 The base (35) of the modiolus faces backwards, and 
 
 forms the anterior boundary of the internal auditory 
 passage (3G). 
 
 CHAP. IX. 
 
 Of the peculiarities in the bony structure of the 
 
 Foetus, 
 
 All the long bones are composed of several parts, 
 viz. the body and the epiphyses; the latter really include 
 all the projections which in the adult state become pro- 
 cesses, but the term is more generally and especially 
 applied only to the ends of the long bones. These three 
 (as they are commonly enumerated) pieces, viz. the body 
 and the extremities of the long bones, are the parts in 
 which ossification commences in as many distinct points, 
 and it is only as the earthy deposit proceeds that the 
 several portions ultimately become connected. Indeed 
 the shaft and extremities of a long bone seldom form 
 one single mass till eighteen or twenty years of age ; 
 prior to that period the bone, if macerated, falls into 
 three pieces, more or less perfectly formed, according to 
 the age of the individual. 
 
 The bones of the skull are quite rudimental in the 
 fcetus, so as to enable the head to mould itself to the 
 pelvis, whilst passing through it during parturition. 
 
 The OS frontis is divided into two portions by the 
 
A DESCRIPTION OF THE BONES. 145 
 
 continuation of the sagittal suture into the ethmoidal 
 fissure. 
 
 The OS temporis consists only of two portions, which 
 are separate, viz. the squamous and petrous ; the mamil- 
 lary portion not being formed till some years after birth. 
 
 The OS occipitis is divided into four pieces, the crucial 
 ridge not having become ossified. 
 
 The ossa parietalia have neither their frontal nor 
 occipital angles formed ; and consequently two large 
 chasms exist, one in front with the frontal bone, which 
 is deficient at that spot; and the other behind with 
 the occipital bone, which is also deficient ; these two 
 openings are called the fontanels, hregmata vel fonta- 
 nellce^ of which the anterior is called the greater, and the 
 posterior the lesser fontanel. 
 
 THE END. 
 
 VIZBTELLV , BRANSTON AND CO. PKINTBKS iLKBT STU EK J , LONPON. 
 
JUST PUBLISHED. 
 
 Vol. I. OF 
 
 ST. THOMAS'S HOSPITAL REPORTS, 
 
 BY 
 
 DR. WILLIAMS, 
 DR. ROOTS, 
 DR. BURTON, 
 DR. LISTER, 
 
 MR. TR AVERS, 
 MR. GREEN, 
 MR. TYRRELL, 
 MR. SOUTH. 
 
 Edited by JOHN F. SOUTH, Assistant-Surgeon. 
 Price 12s. cloth. 
 
 This Volume contains an Account of the most interesting Cases 
 which have recently occurred in the Hospital, and includes the 
 Clinical Lectures delivered by the Medical Officers of the 
 Institution. 
 
 *** These Reports are published every alternate Month, 
 Price 'is. each Part. 
 
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