^ \ '^Vn ^ \t> ^ / Vo \ Jf^ XCl\ LIBKAR.Y / j- J ^ r*"///' 7 ^ cells at all. Recently Renaut has noted the absence of leucocytes in the capillaries of origin of the loose connective tissue of the marmot. All authors find that the number of leucocytes are considerably increased after their pas- sage through the gland. Judging from the somewhat numerous ideas ex- pressed in the older writings, the number of leucocytes in the lymph is very variable, not only in different animals, but also in different animals of the same species : thus Malassez counts only 180 in a cubic millimetre of frog's lymph, Ranvier counts 11,300 in the same quantity of rabbit's lymph, 4,800- and 7,500 in the lymph of the dog, and 8,200 in that of man. 6 THE LYMPHATICS Again one finds some red blood corpuscles in the lymph, but always in small quantities. They are, however, sometimes so numerous as to impart a rosy tint : this rose colouration was specially observed in the lymph coming from the spleen, or from lymphatic glands (Hewson, Gulliver, Lane and Ancel, Simon, Reuss and Emmert). It increases in the lymphatic A r essels which have been blocked by a ligature (Eisner, Retterer), and when the blood pressure rises (Strieker, Hering, Laulanie). Finally, it would appear as though the lymph becomes reddest in starving animals (Collard de Martigny, Nasse). In contradistinction to these last-mentioned authors, I have noted the perfect whiteness of both chyle and lymph in a rabbit and a dog which have died from starvation. Similarly, I have bled some animals without being able to observe the slightest red colour in their lymph an observation already made by Hayem. The presence of red blood cells is not perhaps absolutely constant, since Kolliker has not found them in human chyle, but unquestionably they are frequently present. One cannot agree with Krause, who asserts that lymph collected without accidental mixing with blood, is always destitute of red blood corpuscles. It seems that the presence of some of them may be explained by the reflux of venous blood into the thoracic duct (Colin). In the case of hyperdis tension, others come from blood vessels, either owing to rupture, or by diapedesis. However, it is not probable that such is their sole origin, and without affirming as the old authors have done, that the red blood corpuscles are always derived from the white corpuscles, we may ask if some of them do not come from lymphatic glands. We will study this question when dealing with the functions of these organs. Before undertaking the chemical study of the plasma of the lymph, it is advisable to recall its histological characters. On the one hand, Renaut considers that this plasma contains no albuminoid matter in the capillaries of origin. On the other hand, Ranvier has observed in the trunks, granules of a hyaline substance, myeloid in nature, which are stained yellow by picrocarmin ; these granules are manufactured by the endothelium. Retterer also found granules in the lymphatic plasma. I have observed the same thing in the contents of the lymphatic capillaries of the glands, and of that of the thoracic duct. These granules are more rare in the blood vessels, with the exception of those in the liver. The origin of these granular coagula seems complex : the granules are apparently derived as much from the endothelium as from the protoplasm of the white blood corpuscles. Admitting that secretion takes place to a con- siderable extent within the intraglandular passages, it is possible that the formation of these granules is also one of the products of the secretion of the lymphatic gland. All that we know of the lymph, its origin, and the alterations it most probably undergoes after traversing the gland, lead us to think that it pos- sesses a very variable chemical composition, which depends not only upon the condition of the animal, but also upon the particular vessel from which the lymph is drawn. This explains the discrepancies which have been ob- served in the different analyses published up to the present time, notably by Schmidt, Gubler and Quevenne, Hensen and Dahnhardt ; it also explains the difference which, it is now recognized, exists between the peripheral lymph and the mesenteric lymph or chyle. In reality, the difference simply amounts to this : that the chyle is loaded with fat derived from the lacteals of the intestine. The lymph is a slightly viscous liquid, with no colour, or with a colour GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 7 varying from a slight lemon or hardly recognizable opal, to a yellow tint that is, before its passage through the gland. The moment digestion com- mences it becomes milky. In the thoracic duct and in the efferent vessels of the spleen, we have seen that sometimes it is of a faint rosy tint. It is as a rule inodorous : but some observers detect a faint odour, which varies in different kinds of animal. Others maintain that when cold, the chyle smells like spermatic fluid, and when heated, like fat. It is faintly alkaline to the taste. Its specific gravity varies between 1,015 and 1,045 ; that of chyle between 1,012 and 1,022. It is less alkaline than blood-lymph, requiring 0'35 gr. lactic acid to neutralize 100 grs., whereas blood, requires 0'50 gr. to neutralize the same quantity. According to Krause, the total quantity of lymph equals one-third the weight of the body ; according to Ludwig and Majendie, one fourth ; Bidder says that in the cat and dog it is equivalent (approximately) to from \ to of the weight. In the case of the horse, Schmidt has obtained in twenty-four hours a quantity of lymph equal to the total quantity of blood. More recently Moussu has obtained in ten minutes, from different horses in a state of rest, quantities varying between 0'60 gr. and 6'50 gr. on an average a little more than two grammes. 'In the ox he has also obtained in the same time quantities varying from 2-26 gr. In an ox of average weight the amount is a little more than 10 gr. By making a fistula in the thoracic duct, Colin has obtained 95 kgs. 286 grammes in twenty-four hours. In the dog, Lesser has obtained 300 cubic centimetres in four hours ; in man, 5 litres and a half have been collected in the same time. The quantity depends, we know, not only upon mechanical influences such as pressure, etc., but especially upon cellular activity in all its conditions ; thus, Moussu has collected 5, 10, and even 20 times more lymph from an animal in a state of activity, than from the same animal in a state of rest. Lymph increases fairly quickly under the influence of pilocarpine, less quickly under that of ergotine ; it increases also after the injection of certain toxins (Charrin, Moussu) ; after a hypotensive dose of toxin, viz. diphtheria toxin, and also after a hypertensive dose of toxin, such as tuberculin. Though Beard and Wilcox, and Retterer, firmly believe they have seen the lymph increase after bleeding, Moussu, on the other hand, has stated that in the horse, bleeding to the extent of 4 litres has led to a marked diminution of this fluid. Ranvier has seen the lymph diminish considerably in frogs which have been placed in a vacuum, or kept in a dry place. In the case of the curarized frog, the lymph accumulates in the retrolingual space (Ranvier, Tarchanoff). Regarding the numerous lymphagogues we ought, as Heidenhain suggests, to classify them, and place in the first class such as are of an albuminoid nature, or of animal origin, such as the muscle extract of the crayfish, head and body of leeches, bodies of aiiodons, the intestine and liver of the dog, and the peptones. In the second class, crystalloids : the sugar, salts, and urea, should be included. Outside the vessels lymph coagulates more slowly than blood, taking from five to twenty minutes. 1,000 parts of lymph yield 44*8 parts of clot (Schmidt) ; the same quantity of chyle produces only 32' 6 of clot. The clot is soft, somewhat white, slightly retractile. The serum is colourless and transparent. Coagulation yields considerably less fibrin than that given by the same quantity of blood. In 1,000 parts of lymph taken from the inguinal glands of the bull and cow, Schmidt finds 1*2 gr., 2 gr., and 2'2 gr. of fibrin. In the same quantity of human lymph, Hensen and Dahnhardt find 1'07 gr. 8 THE LYMPHATICS According to others, the amount varies between 0*4 gr. and 0'8 gr. The tendency to fibrin formation and coagulation becomes more rapid, after the passage of lymph through the glands (Chaussier, Albertoni, Hofmeister), and after the action of curare. On the contrary, coagulation takes place more slowly after the action of certain toxins (Charrin). Chemically, lymph is an aqueous liquid which contains albuminoid matters (globulin, serin, fibrin), fat, sugar, urea, salines and gas. The proportion of water is here much greater than it is in blood (from 929' 7 to 987 '7 in 1,000 parts) ; the water diminishes after the passage of lymph from the gland. In chyle there is usually less water than there is in lymph at the periphery (from 904*8 to 964-4). On the contrary, the richness in albuminoid matter is less than that of blood. It ranges from 3' 37 gr. to 52' 9 gr. In the chyle it ranges from 22-25 gr. to 70- 1 gr. Some of the proteid substances of chyle are precipitated by acetic acid, others by alcohol ; their weight may be increased from 30 to 70 in every 1,000 during digestion. The albuminoids also increase in starvation. Fats are met with in variable proportions from a trace up to 30 for every 1,000; in the chyle, after a repast, up to 65 for every 1,000 parts: apart con- sists of neutral glycerides peculiar to the special animal under consideration, the other, of soaps of the fatty acid series, of lecithin (A. Gautier) ; in the chyle, cholesterine and amins are found (Dobroslavine). After passing from the gland, less fat is usually found. The proportion of sugar is low, much lower than that of the blood (Chau- veau). Wurtz only finds traces of it. Poiseulle and Lefort have obtained 0'016 gr. and 0'0098 gr. in 1,000 parts of lymph taken from the dog or cow. In 1,000 parts of human lymph Gubler and Quevenne have found 0*5 gr. There is O'l gr. of glycogen for every 1,000 parts. 100 parts of lymph contain from 0'012 to 0*021 part of urea. Saline matters (chloride of sodium, phosphates, sulphates and alkaline carbonates) are found in nearly the same proportions as in blood from 7 to 15 gr. ; on an average 8 gr. per litre in human lymph. There is some iron in lymph and chyle. According to Hammersten, 100 gr. of lymph contain 42-28 gr. of gas in the following proportions : Carbonic acid gas, 40*32 gr. (from 2840*32) ; nitrogen, 1-63 gr. ; oxygen, 0'43 gr. (from to 0'43). In the chyle, Hensen has precipitated a diastatic ferment by alcohol ; lymph also contains an amylase. Dastre has concluded that glycogen only exists in the plasma in the white corpuscles. Floresco has affirmed that after an injection of propep tones, or of extract of leeches' heads, the incoagulable lymph of the thoracic duct causes coagu- lation of the casein of milk. It contains some rennet, which diminishes during fasting. The lipase exists only in very small quantities (Duclaux). Lymph cannot be a reducing agent, seeing that Gautier (1881) and Ehrlich (1890) having injected coloured substances such as indigo, alizarin and cerulein blues, into a living animal, substances which become dis- coloured while absorbing hydrogen, have stated that it has a tint similar to blood and some of the other tissues. BIBLIOGBAPHY. Magendie. Precis elementaire de physiologic, 1825, II. Noll. Zeitschrift /. ration. Medicin, 1850, IX. Cl. Bernard. Lemons sur les anesthetiques et sur I 'asphyxie, 1875. Lesser. Eine Methode um grosse Lymphmengen vom lebenden Hunde zu bekommen. Arbeiten aus der phys. Anstalt zu Leipzig, mitgetheilt durch Ludwig, 1872. Hammarsten. Ueber GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 9 die Gase der Hundelymphe. Arbeiten aus der phys. Anstalt zu Leipzig, 1872. Robin. Lecons sur les humeurs, 1874. Frey. Eel. fran., 1877. Albertoni. Ueber die Peptone. Centralblatt fur die med. Wiss., 1880, no. 32. Hofmeister. U. das Schicksal des Peptons im Blut. Zeit. f. phys. Chemie, V. Tarchanoff. Do 1' influence du curare sur la quantite de la lymphe et 1' emigration cles globules blancs du sang. Arch. Physiologie, 1785. Krause. Zur Physiologie der Lymphe. Zeitschrift f. rat. Medicin, 1885, \ 7 1T. Colin, Phys. compares des animaux domestiques, 1888, II. Heidenhain. Verusche u. Fragen zur Lehre von des Lymphbildung. Pfliigcr's Archiv, 1 80 1,XLIX. Hamburger. Zeit. f. Biol., 1894. Charrin. C. 7?. Soc. Biol., 1800. Leathes. Journ. of Phys., 1806. Tscherewkow. Archiv. f. die gesam. Phys., LXIT. Fano et Bottazi. Arch. Hal. biol., 1896, XXVI. A. Gautier. Lemons de chimie biol. ct path., 1807. Asher et Barbera. Untersuchungen iiber die Eigenschaften u. die Enstehung der Lymphe. Zeitschr. f. BioL, 1808, XXXVT-XXXVIL Duclaux. Traite dc Microbiologic, 1800, II. Moussu. Recherches sur 1'origine de la lymphe de la circulation lymphatique peripherique. Journal de V anatomic ct de -la physiologic, 1001, nos. 4-5. Ranvier. Traite d'Histologie pathologique, 1001. Retterer. Journal de r Anatomic ct dc la Physiologie, 1001, no. 6. LEUCOCYTES Under the generic term leucocytes, or white blood corpuscles, are included a series of cells which are met with in the blood, the lymph, and connective tissue spaces. Ranvier has objected to this term (\evxos white ; KVTOS cell), which he says only causes confusion by leaving one to suppose that the white cor- puscles are utricular bodies : which is not correct ; others object to the term white blood corpuscle, observing that these bodies, colourless though they maybe, or containing yellow, orange or black particles, are never white. Whilst entirely recognizing the justness of these remarks, we will retain these terms, which have been sanctioned by use, as we cannot replace them by such terms as M migratory " or " amoebic " cells. The amoebic movement is not a feature which is peculiar to leucocytes only ; it is probably common to all cells at all times. We will study : 1. The structure, the physical, chemical and biological proper- ties, the evolution (degeneration and death) of the leucocyte. 2. The different kinds of leucocytes. 1. THE WHITE CORPUSCLE IN GENERAL. Structure. We will consider (1) the nucleus; (2) the proto- plasm . NUCLEUS. In the different kinds of leucocytes, the nucleus varies considerably, not only in its size, shape and situation, but also 10 THE LYMPHATICS in the arrangement and disposition of its chromatin. Large or small, placed in the centre or away from it, it is rounded, oval, elongated or polymorphous, and sometimes actually multiple. The polymorphism of these nuclei has actively engaged the attention of c}^tologists and given rise to many theories to account for it. Even if we admit that by being split up and by a degenerative vacuolization, leucocytes can present multiple perforated nuclei, Flemming, Heidenhain and Vander Stricht, have proved that the polymorphism is not, as Ziegler and Schultze believed, a sign of degeneration, or even of age. For even if we support this latter theory by supposing that the nuclei of certain epithelial cells, which are rounded in young animals, become irregular and twisted as they get older, we must also admit that the mere fact of leucoc} T tes possessing amoeboid properties, and being able to act as phagocytes to nuclei, does not fit in well with the theory that such cells are old or are about to die. We shall, when studying amoebic move- ments, meet with direct and indirect division of leucocytes, what- ever the generic bearings may be which appear to exist between these phenomena and the irregularity of the nucleus. These phenomena apparently are not able to explain all cases of poly- morphic nuclei. It is interesting to compare the budding nucleus of leucocytes the unicellular glands (Ranvier, Lowit) to the ramified nucleus of the immobile glandular cells of certain Invertebrates (forms observed by Mayer, Heider, Korschett, Klaatsch, Mont- gomery). It is worth remarking that these modifications of the nucleus are temporary, and probably coincide with' the secretory activity of the cell ; perhaps the polymorphism, that is to say, the increase of the nuclear surface of certain leucocytes, bears some re'ation to their secretory activity. Sometimes the chromatin is seen as a network of more or less close spaces, sometimes as rounded granules (pseudo-nucleoli) : these latter are as a rule more or less central, bound or not to other peripheral granules which adhere to the nuclear membrane. In the leucocytes of the salamander fixed by sublimate, M. Heidenhain has pointed out the existence of a coarse chromatin network, intimately bound up with a much more delicate network, formed by filaments of linin ; in the meshes of which he has found albuminoid granules, which are well coloured with acid fuchsin. He calls this substance lanthin. Henneguy thinks that it is an albuminous fluid which has been precipitated by the sublimate ; perhaps this fluid corresponds to paralinin. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 11 Lowit, while studying the leucocytes of the crayfish with the reagents of Schwarze and Zacharias, found that their nuclei con- tained much pyrenin. Such, he thought, ought to divide directly. We shall see later on, that leucocytes frequently reproduce them- selves by karyokinesis. Hayem, Ehrlich, and Lazarus note the almost constant presence of one or two nucleoli in small leucocytes (lymphocytes), without stating definitely if they are made up of pyrenosomes or of pseudo- chromatin nucleoli. In certain leucocytes (myelocytes, neutrophiles) Levaditi has coloured, without previous fixing with the brilliant Kresyl blue, forms which he considers resemble nucleoli ? PROTOPLASM. We will study (1) its composition ; (2) its different forms, such as centrosomes and spheres of attraction ; (3) its contents absorbed or manufactured by the cell. Composition. Sometimes simply an almost imperceptible stratum, sometimes well developed, it would appear that the protoplasm of the white blood corpuscles has the power of reacting in many different ways to stains ; at times it is neutral, and at others acidophile or basophile. Sometimes almost homogeneous, it almost always has, according to Flemming, Heidenhain, Schoefer, Arnold and Klemciewicz, a reticular or filamentous structure. In the meshes of the network one finds spaces filled with a homo- geneous and liquid substance ; the vacuoles are more or less abundant, according to the cells considered. Schoefer has stated that the leucocytes, which have been fixed on a slide by the rapid action of a jet of steam, present a reticular structure in the centre, whereas the pseudopods remain clear ; he therefore concludes that the latter are simply hyaloplasmic expansions ; Henneguy likewise, has found a structure purely vacuolar in the central part of the leucocytes of earthworms, in which the pseudopods are homogeneous. Arnold, after macera- tion in a solution of iodo-iodide. has seen corpuscles which are sometimes rounded, but which are more often elongated in the form of little rods (plasmosomes). These plasmosomes show filiform prolongations, which unite in a thousand ways so as to produce a filamentous, reticular or spongy appearance ; they traverse spaces filled with a hyaline paraplasm. Klemciewicz observes a filamentous structure composed of vacuoles in the centre and an ectoplasm at the periphery : it is perhaps due to this ectoplasm that the cellular juice, in spite of 12 THE LYMPHATICS the large amount of water it contains, does not continually mix with this surrounding liquid : at all events, this structure enables us to understand the frequency and ease with which changes can take place between the cellular contents and the surrounding medium. Centrosomes, ami Spheres of Attraction. The centrosomes of leucocytes have been studied by Flemming, Hansemann, M. Hei- denhain, and Henneguy. Hansemann has observed centrosomes with spheres of attraction and rays emanating from them in the leucocytes of young granulation tissue ; Heidenhain, in human leucocytes and in those of the salamander, by means of iron haemotoxylin ; after examining 1,000 cells in a state of rest, he found that 74'6 out of every FIG 2 centroso- 100, nac ^ ^ wo unec t ua l centrosomes, and 19'1 out mes of ceils from the o f every 100 two equal centrosomes. He admits lymphoid cortex of T the liver of the Saia- as a rule, there are two centrosomes. In a cer- mander (after Henne- tain num ber of cells, by the side of the t-WO guy). J centrosomes, he has seen one or two accessory corpuscles, very small, and almost colourless. The three or four elements are joined together by brownish or grayish filaments, and the whole (microcentre) resembles a triangular or tetrahedric figure. In the lymphoid cortex of the liver of urodelic amphibians, Henneguy has found in almost all the cells (leucocytes having a polymorphous nucleus or basophilic granules), a centrosome which appears like a coloured point, surrounded by an aster. The centrosome as a rule is situated in the concavity of the nucleus. In some cells in which the nucleus is about to divide, Henneguy has seen two centrosomes a little distance from each other. The Contents. The contents of the leucocytes, both naturally, and through production, are exceedingly variable and are numerous. We need only mention for the present the particles of exocellular origin, debris of microbes, and of red blood corpuscles, iron granules, which are digested by the white corpuscle, also the presence of chromatin granules, excreted by the nucleus and the protoplasm (Nebenkern of certain authors). In the migratory cells of the intestine of the salamander during chromolysis, Lukjanowhas seen juxtanuclear corpuscles coloured red-brown by the stain used by Biondi : but the most important contents are without doubt the cytoplasmic granules, recognized ever since Wharton Jones and Max GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 13 Schultze drew attention to them, and since studied by Semmer, Pouchet, Ranvier, Renaut and Hayem. The works of Ehrlich and his pupils have accurately determined their histochemical reactions and especially their affinity for aniline dyes, and in studying the behaviour of these granules towards stains, Ehrlich has recog- nized that they show a particular predilection for certain aniline colours. Admitting that the majority of these colouring matters are salts, he has for the sake of convenience called those in which the principal colouring is furnished by the base, basic ; those in which the mixed colour is due to the acid and the base, neutral. Granules are termed acidophiles, basophiles, or neutrophiles, accord- ing to their affinity, that is to say, according to how deeply or how exclusively they stain with one or other of these colours, described above as acid, basic, or neutral. Eosin, orange, acid fuchsin, are acid colours ; methylene blue, safranin, methyl green, are basic colours. Amphophiles are granules which, in a mixture of acid and basic colourings at the same time, retain the two colour- ing matters : the coarse refracting granules in the leucocytes of Semmer are eosinophiles, that is to say, acidophiles ; they are also called oxyphiles, but Ehrlich designates them by the Greek letter a ; Ehrlich has also found two sorts of basophilic granules : 7 and 3 ; the granule 7 is stained by basic colours without change of colour; the granule B shows the phenomenon called metachro- masis : it is coloured red by the polychromatic blue of Unna. In the leucocytes with a polymorphous nucleus, one finds a fine granule which in a mixture of methyl green, orange and acid fuchsin is stained violet : this is the neutrophile granule e of Ehrlich. The neutrophile of this granule has been discussed : Gulland, Kanthack, and Hardy, have asserted that Ehrlich's mixtures were not neutral, but acid, and that in reality the granule e was acidophile (fine oxyphile granule). Others, Maragliano, Zap- part, etc., think they have found all transitions in shape and in colour between a and e. Perhaps we may consider this granule e amphophile in nature ? This is the opinion of Dominici, who, recalling the fact that Kanthack, Hardy and sub-equently Jolly have stained it by eosine, adds that it is equally well stained by basic colours. There is still another granule whose significance has given rise to numerous controversies : it is a smaller and more refracting granule than a, which in leucocytes with polymorphous nuclei, in 14 THE LYMPHATICS the blood of the rabbit and of the guinea pig, has been described by Ehrlich and Kurlow under the name of pseudo- eosinophile, and designated by the letters j3 E. Is this acidophile or ampho- phile ? Should it be classed with a or 6 ? In favour of a should be mentioned not only its marked acido- phile nature, but also its insolubility in water, ammonia, ether, alcohol, chloroform, turpentine, formalin, sublimate, and the fact that it stains yellow by iodo-iodide solution. If differs from a by its solubility in acetic acid, by the fact that it is more eosinophile than orangeophile, more indulinophile than eosinophile. In favour of e must be noted its violet colouration by the triacid, 1 its basophilism which some consider just as well marked as its acidipholism. In a mixture of blue of toloidin and eosin, Dominici has stained it a violet red ; it differs from e in being larger, in its insolubility in water, and in its acidophile properties being more marked. (Its staining by eosin is not hindered by the haematoxy lin.) It differs therefore both from a and e. It is interesting also to notice its presence in the leucocytes of the guinea pig and the rabbit, which by their number, dimensions, the polymorphism of the nuclei, and especially by their physio- logical properties (amiboism, phagocytosis), appear to be the homologues of poly nuclear cells with neutrophile granules. Thus from one animal type to another, we find that the same cell manufactures products, which in appearance at any rate differ from each other. In birds, various crystalloids appear to correspond to the granule a. We may also observe that though the acidophile granules are very scattered in the animal series, and we find them not only in the vertebrates, but also in crustaceans, spiders, insects, oligochetae, sipunculae, the lamellibranchs, the psorobranchs, basophilic granules appear to be peculiar to the vertebrates and the sipun- culae (Cuenot). According to this author, the white corpuscles of the pulmonate gasteropods alone, seem to be destitute of granules. On the other hand, it is quite possible that the absence which he mentions is more apparent than real, for, following the same line of thought, Ehrlich notices the fact that, though Hirschfield did not find neutrophile granules in white mice, Miiller has done so by a special method. 1 However, if I may judge from some of my own personal observations, its amphophilism is not constant. In Biondi's mixture, after fixation with sublimate, it has appeared to me, to be stained by acid fuchsin only. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 15 The existence of these granules appears clearly proved, seeing that the largest of them are visible in the living cell, and nearly all may be made apparent by methods of fixation and' by many different stains. By the so-called vital stain, from neutral red, the majority of them become stained an orange red, a few red only : their reaction is then nearly always alkaline (Ehrlich). Though we know their morphology, their affinity for colours, and their solubilities, we are still very ignorant of their true nature : perhaps they are albumins (Weiss, Lowit, Sciawcillo). It is almost certain that they are not debris blood-cellular or microbic, or former phagocytes, as has been thought bySacharoff, Hardy, Lew Bonn Keng, Tettenhamer, Metchnikoff and Mensil. Are these bodies constituents or products of cytoplasm ? Some have wished to identify them with the bioblasts of Altmann ; Arnold, observing their arrangement (tendency to form little chains ?), and their relations with the stable cellular bodies, thinks they represent transformed plasmosomes : this opinion, adopted by Schultze and Gulland, is contested by Ehrlich, Renaut, Lowit, and Heideiihain : Ranvier thinks the question is one of cellular secretions. Some cells seem to owe their preservation to the reserve material they possess, as is the case with vitelline granules. Others are expelled with or without preliminary dissolution. In the same way, granules secreted by certain granular cells dissolve themselves. We may ask again whether these granules represent a particular elaboration, or whether they should be regarded as forming a substratum of soluble fer- ments, the presence of which in the protoplasm of leucocytes is demonstrated by chemistry. In this connection it is as well to remember that those white corpuscles, which have no granules, have the power of digestion, well marked : again the macroeytes (cells of Metchnikoff) which appear to possess a soluble ferment are capable of dissolving red blood corpuscles (macrocytase of Tarassewitch). On the other hand, there are ferments in the nucleus which has no granules. After all, what is the physiological value of distinctions established by the study of colour reactions ? Without attempting to settle this question off- hand, we must remark that differences in staining do not always imply im- portant differences in chemical constitution, seeing that a simple dehydra- tion is quite sufficient to alter the staining affinities of a granule : besides differences of chemical constitution do not always correspond to different physiological meanings : Haemoglobin of man does not crystallize like that of the guinea pig, yet both serve the same purposes. May not we sup- pose that the same is true for the granules /?E and e ? But the existence of granules in white corpuscles has raised other problems : It has been a moot point if cells with granules always come from granular cells, and if two kinds of granules, and 8 for example, can be met with in the same cell. If it is quite certain that the granular cells can again reproduce themselves, it seems almost proved that, originally these cells are derived from non-granular elements. The place of production of these granules has given rise to much discussion : it does not seem probable that it habitually takes place in the blood. It is in the marrow of bones, sometimes even in the glands, and in the spleen that these granules develop. Can two different granules, viz. e and 8, e and a coexist in the same cell ? At first sight it seems easy to reply in the affirmative, seeing that a number of authors (Ehrlich, Schwarze, Weiss, Schaffer, Fischl, Miiller, Hirschfield, Bettmann, Arnold, Engel, Levaditi, Jolly) have found in the 16 THE LYMPHATICS same cytoplasm two granules having inverse colouring affinities. In reality, however, the solution to this question is more complex, for the presence of basophile granules in an eosinophilo cell does not necessarily prove the co- existence of granules a and 8. To demonstrate this fact, it should be proved that the superadded basophilic granule is identical with the true 8, not only in its colouring properties, but also in its morphology, and especially in its chemical properties (solubility or insolubility). Thus, for example, Arnold finds basophile granules by the side of granules a or y3E, these not being metachromatic are not identical with 8. Engel finds in the same cell, granules 8, e, and a, but as the histochemical characters are not given, it is impossible to know if the superadded granules are the true e and a. More- over, it can be understood how complex the question becomes, when even the coexistence of a and e is in question. We know that c has in turn been regarded as neutrophile, acidophile, and amphophile. Though it has not been demonstrated that two granules distinct and classified (a, /?, etc.) can coexist in the same element, it is quite certain that the same element can contain granules which colour differently. What is the significance of superadded granules which are still called heterochromatic ? Ehrlich having found indulinophile granules in the young eosinophiles, and having shown that they had the chemical reactions of a, and that when dehydrated, the}' distinctly became eosinophiles, thought that they were young forms in process of development. We know that other elements, such as the red blood corpuscles, are polychromatophile before becoming acidophiles. Bettman thinks on the contrary, that the presence of basophile granules is a sign of degenerative process. Is this always so ? It would seem not to be the case. Quite recently Leva diti has observed Ehrlich's cells (Mastzellen) which contained granules, colour reddish-violet by the triacid, and violet-red by the eosin blue of methyl- methylene. They resemble t not only in their staining affinities, but also in their solubility in potash (2-100) and in acetic acid (3-100): they differ however in staining deeper red with the triacid, in their insolubility in distilled water, and in their larger size : they differ from 8 in their colour and their shape: they resemble 8 in their solubility in acetic acid. Levaditi thinks they are new granules, which bear no relation to those already known. While noting these mixed and complicated characteristics, we may perhaps ask whether forms intermediate between those of 8 and e cannot exist ? For will it not be granted, that it is a property of intermediate forms to present mixed characters, which are no longer entirely those of the primi- tive form, but which already bear some resemblance to those in a later stage of development ? Moreover, one can well understand how by their nature, such characteristics leave the field open to arbitrary interpretations, and the question of whether they are, or are not, transitional forms amongst the various kinds of granules pointed out by Ehrlich, will for some time remain a source of discussion. Physical Properties. Nearly always colourless but some- times tinted, of a variable refraction, opaque or clear, the leucocytes are soft, protoplasmic, extensible masses, with no covering. They are heavier than plasma but lighter than red blood cells : they are viscous and adhere to the smoothest surfaces. When the circulation GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 17 slackens, they accumulate against the vessel-wall, and resist the current which carries them along. Placed upon a glass slide, they adhere to it. and are not carried away by a drop of water, which by its capillary action drives away the red corpuscle. As the researches of Berthold seem to show, that a protoplasmic drop, denuded of membrane, possesses the physical characteristics of a liquid, it may be supposed that at rest, the leucocyte is rounded by the superficial tension being equal at all points on its surface ; this tension is similar to. but weaker, than that of globules of butter suspended in milk. Though this illustration is suggestive, it is not absolutely correct, for as we have seen, the protoplasm of the leucocyte is far from being homogeneous. Chemical Constitution. Though still far from perfect, our knowledge of the chemical constitution of leucocytes has in recent years been enriched, by interesting theories not only in cell, but also in general physiology. In 1871, Hoppe-Seyler analyzed globules of pus which he separated from the liquid which contained them. He found in 100 parts of leucocytes 13*762 undetermined albuminoids. 34-257 nuclein. 20*566 insoluble substances. 14-384 lecithin and fat, 7 '400 cholesterin. 5* 190 ccrcbrin. 4*433 extractives. The ash contains phosphoric acid, chlorine and numerous metals (sodium, potassium, calcium, magnesium, iron). Quite recently, Stassano and Bourcefc have found in the leucocytes of normal blood another metalloid, iodine. As regards iron, the researches of Arnold, Hayem, Quiucke, Barker, Hansermann, prove its presence in leucocytes, to be, if not constant, at least frequent. Arnold has seen leucocytes ingest exogenous iron, and Rouget has shewn that the same cells absorbed the old red corpuscles ; and all patho- logists after Vircho\v, know that residual pigments of old ha?morrhagic foci are carried away by leucocytes. According to Quincke, red blood corpus- cles after being eaten are transformed, some into yellow granules, others into colourless albuminate of iron, which can only be detected by histo- chemical analysis. Barker believes in the presence of iron in eosinophile granules. Hayem says that certain leucocytes are overcharged with haemoglobin, especially after bleeding. These last statements, and all those old, or new, which being founded on mere appearances, or colour reactions, allow us to infer the haemoglobic degeneration of leucocytes, should be received with the greatest caution. It is, however, fairly certain that the protoplasm of leucocytes may contain the most various kinds of metals, iron frequently, if not always. This statement is not without interest, now that we are aware that their protoplasm is rich in soluble ferments. Wo may in fact, suppose that there, the metal, as shewn in the experiments of Bertrancl, and Hanriot. plays a part in the action of the diastase. Before 18 THE LYMPHATICS studying these diastases, we ought to say a word about the ternaiy and qua- ternary substances of the leucocyte. As regards ternary substances, the white corpuscle may contain fats and glycogen. The leucocyte of invertebrates sometimes accumulates fat in reserve without undergoing degeneration, exactly as the adipose connective tissue cell of higher vertebrates does. Cuenot expressly mentions that this is the case with the leucocytes of Tuniciers. Nevertheless, the same author remarks that in some leeches, and in some of the molluscs (cloris tuberculata), ascidies, and batrachians, the fat is specially seen in old cells, or in cells of anaemic animals and in fact, among the higher vertebrates, fat is scarcely seen except in disease or in dying leucocytes ; it is not an addition, but obviously a fatty degeneration. In the same way, the dead leucocytes from pus are very rich in fat. Nevertheless, in mammals the white corpuscles, which, traversing the intestinal epithelium, absorb fat from the lacteals, are an exception to this rule. In the lymphatic cell of cold blooded animals, Ranvier has noticed that the glycogen which was sticky, was somewhat diffused. In mammals, glycogen does not exist constantly in the protoplasm of the leucocytes. After injection with chloride of sodium, staphylococcus, and streptococcus, Salmon has seen glycogen appear in the lymphocytes, and in the polynuclear cells, but never in the macrophages. This simple fact should suffice to show how wrong this author is in maintaining that the glycogen takes a part in the mechanism of the defence of the organism, by means of the white corpuscles. All facts point to the contrary. In pus, the quantitative varia- tions of glycogen are considerable (Kiihiie, Jaft'e, Kramer, Lilienfield). Huppert has seen variations between mere traces and T67 gr. The glycogen of the leucocytes appears under the most diverse morbid circumstances (nar- coses, diabetes, severe contusions, etc.). According to Salmon, this glycogen presents itself in various forms, viz. as crescents, concentric rings with a cellular outline, or even balls, or excrescences which remind us of amoebic prolongations. Sometimes these balls leave the leucocyte and fall into the plasma. The mahogany brown colour which iodine gives to glycogen becomes pale between 50 and 60 (Errera) ; and disappears between 65 and 73 (Can- trian). This glycogen appears to be very stable (Lepine), and it probably has several sources ; the leucocyte is in fact capable of absorbing either glucose, or starch. We shall see that it can convert the latter into sugar. We may then ask, can this white cell, like the liver cell, by hydrolysis, transform the sugars, ingested by it, into glycogen ? It can be clearly seen, that after the peritoneal injection of glucose, the Ieuc9cytes become charged with glycogen ; but, as the same thing happens after a simple injection of sodium chloride, we should be cautious in our interpretation of the fact. On the other hand, we may imagine that this glycogen is formed at the expense of some of the albumins in the leucocytes ; in fact, Kossel, has shown that nuclein and histon become decomposed in exonic bases, with which it is interesting to compare the products of the decomposition of polysaccharic bodies. We know that Hoppe-Seyler mentions the existence of an undetermined albuminoid and of a nuclein ; Gautier calls them nucleo-albumins (hyaline substance of Rovida, globulin of Halliburton). This study has been developed by Hofmeister, Lilienfeld and Kossel. Hofmeister has found abundant peptones in the leucocyte. Lilienfeld GENERAL ANATOMY OF THE LYMHPATIC SYSTEM 19 has obtained from the aqueous extract of leucocytes, after centrifugalizing and filtration, and then precipitating by acetic acid, a white powder insoluble in acids, but soluble in water and weak alkalies; this is the nucleohiston which, treated by alkalies, dilute acids, or boiling water, splits up into leuconuclein. (acid), and the liiston of Kossel (basic). There is in every 100 parts of leu- cocyte 68*8 of leuco-nuclein and 8'7 of histon. The iiuulein is capable of giving rise to uric acid. The elimination of this acid in the urine increases considerably in certain leuchaemias. Thus, we may imagine that the leucocyte plays a part in the process of the break- ing up of nitrogen within the organism. From another point of view, it is no less curious that nuclein and histon, two protamines, which come from the same cell, or at least from the same kind of cell, possess antagonistic physiological properties : the former favours coagulation, while the latter hinders the process. Normally, there are pigments in some of the leucocytes of cold blooded animals (Cuenot, Renaut), and, abnormally (foreign bodies, melanin), in those of warm blooded animals. It is now a well established fact that leucocytes produce, or at any rate contain, soluble ferments, and that consequently, they are capable not only of absorbing foreign bodies, but also of actually digesting some of them. Heckel, who has seen blue granules of litmus which have been digested by leucocytes become red, thinks that such digestion takes place in an acid medium. Metchnikoff thought at one time it took place in a neutral or alkaline medium ; but having since recognized that the vacuoles were coloured brick red by the neutral red, he too now thinks that it takes place in a slightly acid medium. Ever since 1888, Leber has affirmed that aseptic pus digested fibrin and liquefied gelatine; these properties he found were destroyed by heat. In the leucocytes of the tonsils, Kossbach has found an amylase ; and more recently Zobolotny has found the same in the peritoneal leucocytes of the guinea pig. It would seem that the effects of this ferment are sometimes somewhat slow in manifesting themselves ; but perhaps it does not exist in all leucocytes and in all animals. Such is doubtless the explanation of the negative results announced by Schoefer, Xetchaeff and Salmon : nevertheless Salmon has seen ingested starch become dextrin. According to Lepine, the glycoly tic diastase, manufactured by the pancreas is apparently fixed in a provisional manner by the white corpuscle. Portier, and later on Brandenburg, have studied the oxidizable ferments of leucocytes. Mantegazza and Schmidt those of the plasma. The plasmase has been found by Jacob, Lowit, and Schattenfroh in extracts of leucocytes ; it would seem to be very abundant in the nuclei. This fact proves that one must be slow in establishing a connexion between the presence of these ferments and those of cytoplasmic granules. Just as the holocrine glands, in order to set free the products of their elaboration, destroy themselves, so the leuco- cytes have to die, so that the plasmase may become diffused into the sur- rounding liquid. Also we have been enabled to state, that the coagulability of blood is more rapid, in proportion as the white corpuscles offer less re- sistance. In the macrocytes, Delezenne has found the enterokynase, and Tarassewitch, the macrocytase. In aseptic pus, obtained by injection of turpentine, Achalme has found the amylase, the oxydases, the ferment liquefying gelatine, and also a ferment allied to trypsin, a casein and a saponin. Cuenot and Cattaneo think that in the white corpuscles of crustacean decapods there is a ferment which forms haemocyaiiin. Thus, in spite of indi- 20 THE LYMPHATICS vidual variations, leucocytes can take on the many functions of hepatic, pancreatic and renal cells, functions which they exercise not only in definite places, but actually within the tissues themselves. In fact, like the hepatic cell, they are capable of manufacturing glycogen, of storing up fat; and like the pancreatic cell, they can produce anamylase and yield a glycolysin; like the renal cell, they can take part in the ultimate mutations of nitrogenous matter, inasmuch as they give rise to uric acid. These unicellular glands are then, not simply organs of assimilation and storehouses for the accu- mulation of nutritive stores, but they are also excretory organs. Biological Properties. The white cell possesses all the prim- ordial properties of living matter : sensibility, mobility, powers of absorption, of secretion, of reproduction. Mobility. This has been recognized for a long time, in fact, ever since Wharton Jones in 1846, observed the pseudopodic displace- ments and expansions of leucocytes in the blood of the ray-fish and of the frog. Some years later, in 1850, Davaine made the same observations in the white corpuscles of human blood. These changes of form were compared by Lieberkiihn to those of amoebae, and now. they are known by the term Amiboism, or amoebic movement. The leucocvte becomes spheroidal, throws out a prolongation or pseudopod, which ramifies : then the cellular body becomes displaced and blends with this expansion, and so on. At one time, the protoplasmic expansions are lobed, rounded and fairly large ; at another, they are broken up, or are filiform, like needles. The pseudopods of eosinophiles appear to be less slender than those of other leucocytes (Max Schultze, Jolly). According to Flemming and de Bruyne, there are no lobopods in circulating blood ; the fine pseudopods are produced in corpuscles which have left the vessels. Side by side with these movements, there appear to exist endo- plasmic movements which, without displacing the cell, displace the granule and perhaps the nucleus also. According to Ranvier, this nucleus exhibits, under the influence of these protoplasmic movements, passive changes ; the buds, the constrictions, and even the divisions which are seen, result from the activity of the protoplasm which constricts, by a kind of con- traction, portions of the nuclear mass just as a ring does a sac. Sherrington, Dekhuysen, Gulland and Korschelt think the same ; Jolly sees in the polymorphism of the nucleus a sign, and even in fact, a result of the amoebic activity of the cellular protoplasm. Metchnikoff , and Heidenhain find in the appearance of the multi- lobed nucleus one of the indications of the adaptation of leucoytes to diapedesis. Ehrlich long ago remarked that the poly nuclear GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 21 leucocytes shift their position more frequently and in greater num- bers than is the case with other leucocytes. Metchnikoff insists on the relative rarity of this nuclear type amongst a vascular inverte- brates, and thinks it evident that a nucleus, which is broken into several fragments, must traverse the vascular wall much more easily than a large entire nucleus. It is quite evident that neither the theory of Ranvier, nor that of Metchnikoff can explain the genesis of all the polymor- phous nuclei. Do they hold good for any of them ? The observations of Ranvier and Jolly show the concomitance of nuclear and protoplasmic modifications, without establishing any evidences of casual relationship. In fact, they take for granted, but do not prove the passivity and immobility of the nucleus ; they do not explain the polymorphism of the nucleus of certain immobile cells, and the almost absolute spheroidal shape of the nucleus of certain amoebic cells ; Demoor, however, after para- lyzing the protoplasm of the leucocyte by chloroform, has seen movements of the nucleus. While admitting with Jolly, that in the case of the leucocytes of the frog, these observations must be received with caution, it is none the less certain that; at certain periods of its life (direct and indirect division), the nucleus has the power of movement. Jolly attempts to explain the twisted shape of the nucleus of immobile cells by supposing that the nucleus has not had time to return to its rounded shape. It is quite possible that this expla- nation may be true in some particular cases, but no generaliza- tions should be made. Besides, this polymorphous nucleus is seen in cells which have never been mobile. When he discusses the rounded shape of the nucleus of amoebic cells, Jolly expresses the opinion that cells cannot exhibit exoplasmic movements without influencing the nucleus. Though doubtless such movements exist, the main point to be settled is. whether the mononuclear cells travel solely by means of similar movements. As so little is known about this question, we may conclude with Lavdovsky, Hardy and Wresbrock that, contrary to the opinion of Ranvier, it is not yet proved that abnormal nuclear shapes are purely passive formations, or are directly dependent on protoplasmic contractility. The theory of Metchnikoff is open to the same and other ob- jections besides. We will not return to the question of the dia- pedesis of mononuclear cells, or to the polymorphism of the .nucleus of certain immutably fixed cells, but will content ourselves c 22 THE LYMPHATICS with the remark that, though certain shapes of polynuclear cells appear well adapted for their passage across narrow intercellular spaces, there are others (shaped like an in rose work) which, are certainly not adapted for endothelial migrations. To change their position, the leucocytes make a considerable effort (Engelmann). To understand this, we must remember that they possess a superficial tension, feebler, but of the same kind as fat globules suspended in an aqueous liquid. In a damp chamber. Lavdovsky has seen leucocytes pass through and through a clot of blood. The white corpuscles of cold-blooded animals manifest their amoebic movements at the surrounding temperature ; those of warm-blooded animals only between 20 and 37. Heat excites this activity ; a temperature of 43 kills them, producing at the same time a round shape. Oxygen is necessary for their life, and especially for a manifestation of their motor powers ; thus if a small piece of phosphorus be introduced under the skin, absolutely no leucocytes will arrive on the spot, because phosphorus absorbs all the oxygen in the neighbourhood. Rollett, Goluber and Engelmann have stated that under the influence of inductive shocks, leucocytes withdraw their pseudopods and assume a spherical form : strong currents kill them : weaker ones momentarily paralyze them. Ranvier thinks it is difficult in such experiments to entirely eliminate causes of error of chemical origin (electrolytic action of the current, etc.). Carbonic acid, carbon monoxide, hydrogen, quinine, curare, and chloroform paralyse, and then kill the leucocytes. The aqueous humour of the frog is an unfavourable medium for these cells. Owing to their mobility, the leucocytes are well called migratorv cells ; they frequently leave the lymph and the blood to diffuse themselves into the neighbouring tissues (Recklinghausen, Waller, Cohnheim, Strieker and Sanderson, Metchnikoff, Sabatier, Pouchet, Kowalewsky, Durham, etc.). As is proved by a series of classical experiments, they can traverse porous bodies ; at one time, they move in intercellular spaces, (arai^aTa) : at another, they perforate cellular protoplasm (fenestrations of intestinal cells) : a certain number of them definitely leave the internal medium to lose them- selves for good and all one may say on the exterior, either on a cutaneous surface or within the intestinal canal. Thus we may conceive of the possibility of an elimination brought about by leuco- cytes. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 23 Durham stated that in this way leucocytes excreted foreign substances, which had been experimentally introduced in to the body of Asterias rubens. White corpuscles with similar functions have been noticed in the ovary of Lacerta agilis, and of mammals, by Strahl and Lowenthal. Now, is mobility a property common to all leucocytes without exception ? The problem is difficult, because it is always a difficult matter, without staining, to know with which variety of leucocyte one is dealing. Under these conditions, for example, it is impossible to know if one is observing an eosinophile or a leucocyte with basophilic granules, or even a small leucocyte with neutrophilic granules. The most amoebic of all are the corpuscles with neutrophile granules. Next come the large corpuscles without granules, and. the eosinophiles. In opposition to Renaut's views, the amoebic character of the latter has been shown by Max Schultze, Bizzozero, Mayer, Weiss, Miiller and Rieder, Lavdovsky, and Jolly. From his researches on leuchaemic blood, Jolly came to the con- clusion that as a general rule, the small corpuscles without granule, are not mobile ; sometimes, however, he has seen, as Rieder has, small mobile corpuscles. This fact has lately been confirmed by Hirschfield and Wolff. The amoebic character of leucocytes, which has been affirmed by great observers, is easy to verify, and is a positive fact, which the dissentient opinions of Semper, Griesbach and Retterer cannot shake. We may remember that, according to Griesbach, the migration observed in vitro, is only the result of adherence, and of the diffusion and absorption of gas, and that, according to Retterer, the pseudopodic expansions are only " the result of hydra- tion, and of the disintegration and exhaustion of the cellular body." Now. can we conceive the mechanism of this mobility to be an elementary manifestation of a contractile substance of the most primitive kind ? Engel- mann has attempted to apply to the movements of this protoplasm, deprived of double refraction, his thermodynamic theory of muscular contraction. He supposes that there exists in the protoplasm of the amoeboid cell, innumer- able contractile elements, too small to be visible even under the strongest magnifying powers ; these elements, are heaped up without order, and are elongated, and when they swell become spherical. From this swelling results the formation of pseudospores. It will be seen that these are pure hypotheses which, are rejected with reason, by Ver worn. To the latter author we are indebted for a theory which at least is very ingenious. He thinks that, the mobility of the leucocytes, like all the phenomena of contraction, results from the alternation of two opposite phases; one, that of contraction, in which the surface dimin- 24 THE LYMPHATICS ishes in relation to its mass (spherical form), the other, that of expansion in which the surface increases (pseudopodic formations). The leucocytes, having a superficial tension analogous to that of liquids, we may suppose that when they are spherical, they possess a superficial tension equal at all points of their surface. In the same way, when they throw out a pseuclopod, it is because their superficial tension diminishes at this point. What then are the causes of this augmentation or diminution of superficial tension ? Tf we grant that pseudopods form in presence of oxygen, and disappear in its absence, and taking this gas as an example, Yerworn supposes that it is the unilateral excitant capable of diminishing the superficial tension at any one point of the surface of the leucocyte, and consequently of producing pseu- dopods. It would diminish the superficial tension, and at the same time lessen the cohesion which exists between the different organic molecules. Under the influence of oxygen, or of excitants of de-assimilation, the organic molecules would decompose spontaneous!} 7 , the superficial tension increase, and the leucocyte again become spherical owing to the retraction of the pseu- clopod previously formed. Like all theories, that of Yerworn is open to certain objections ; in the first place, the protoplasm of the leucocyte is not homoge- neous ; and secondly, we do not know for certain in what manner the oxygen diminishes the superficial tension, etc. However, the theory has the merit of being suggestive, and of showing or, at least, attempting to explain the meaning of chemiotaxic phenomena, positive or negative. Chemiotaxis is not a mysterious attraction or repulsion ; it comes from the kind of movement peculiar to the cellular form considered. In the instance given above, the one sided excitant is oxygen which, by diminishing the superficial tension, brings about the appearance of a pseudopod on the excited side ; the leucocyte moves towards the oxygen, and then is said to have a positive chemiotaxis. Now, there are unilateral excitants which, on the contrary, increase the superficial tension at the excited point : the pseudopod forms on the opposite side, where the stimulus to contraction is small, and where the protoplasm can extend without hindrance; the leuco- cyte now moves away from the excitant, and there is negative chemiotaxis. Besides oxygen, albuminoid substances (casein of gluten, an emulsion of flour, peas and wheat) ; ferments (laccase) ; microbic toxines, and the greater number of pathogenic microbes or saphrophytes, produce positive chemio- taxis. Lubarsch has shown that living bacteria are productive of a posi- tive chemiotaxis ; more marked than that caused by the same bacteria previously heated. From the researches of Peckelharing, it follows that bacteria cause a more intense chemiotaxis than inert bodies such as fila- ments of cotton ; on the other hand, quinine, jeguirity, chloroform, alcohol, glycerine, lactic acid, solutions of salts of soda and potash up to 10 per cent., the microbe of chicken cholera induce a negative chemiotaxis. In the curarized frog, there is no leucolysis as Drozdoff imagined, but emigration en masse of white blood corpuscles into the lymphatic channels (Tarchanoff). Water, weak solutions of salt, of soda, and potash, peptone, phloridzin, krea- tin, kreatinin, and allantoin do not provoke chemiotaxis. The sensibility of leucocytes varies according to the species of the ani- mal, and the age of the individual. The leucocytes of mammals appear to be more sensitive than those of cold blooded animals (Gabritchevsky) ; and according to Borisoff, they are more sensitive in the young than the old. This author has stated that none of the substances used in his experiments attracted one variety of leucocyte rather than another. In the same subject I have seen the same microbe provoke leucocytic reactions, vanning in GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 25 kind according to the organ under observation. Sometimes, on the contrary, certain varieties of white cells are phagocytes to a certain microbe to the exclusion of all other kinds of microbe. Thus, Metchnikoff thinks that the polynuclear cells surround the streptocci of erysipelas and the gonococci, but this is not the case with the mononuclear cells ; the latter, however, surround the bacillus of Hensen, but this is not the case with the polynu- clear cells. Similarly, in the experiments of Besredka, it was the macrocy tes (large mononuclear cells) which were invariably and exclusively attracted by the tersulphide of arsenic. Nevertheless, it cannot be supposed that as a general rule each type of leucocyte possesses a special chemiotaxis. Granted this fact, and granted that the same leucocyte, whether neutrophile or eosinophile, is attracted by the most different kinds of microbes, it may be seen that even for pure infections, the qualitative study of leucocytosis is of little use in aiding us in our clinical diagnosis. Absorption of solid particles and typical elements (Phagocytosis). For a long time it has been known that leucocytes absorb the solid amorphous particles of cellular debris. So long ago as 1862, Heckel discovered that the leucocytes of Thetys devoured grains of indigo. Recklinghausen, Preyer, Schultze and Balbiani have made similar observations on different objects. Virchow, Koelliker, and Langhans have seen that blood debris from old haemorrhagic foci was carried away by white cells. Arnold discovered the presence of iron, not only in protoplasm, but sometimes also in the nucleus ; Jolly has seen grains of starch, depressing the nucleus, whilst others were found in its centre ; producing an appearance like that of two projections from the nucleus, joined together behind the foreign body which is thus incorporated. These facts ought to open new views in biology. Since leuco- cytes absorb solid particles of colouring matter, we may suppose that they do the same for insoluble chemical substances, whether useful or detrimental. As a matter of fact, Besredka has observed the phagocytosis of the tersulphide of arsenic ; Arnozan, and Montel, that of calomel, and of salicylate of soda ; Landerer, that of balsam of Peru. In the same way, contrary to the old dictum corpora non agunt nisi soluta, we may imagine that the organism utilizes in- soluble substances. We may and we must admit that assimilation takes place within the tissues themselves, and outside the digestive canal. In a word, since the leucocytes absorb cellular debris, we may suppose that they may also be capable of digesting animal or vegetable cells (microbian). Since 1874,Rouget has observed haematophagic leucocytes, which after destroying the red blood corpuscles ingested by them, changed into pigmentary cells. Metchnikoff has studied the hist oly sis of the Sponges, Echincderms, and Amphibians. In the 26 THE LYMPHATICS same way, the works of Kowalewsky, and van Rees, have endea- voured to show the importance of the role of myophagic leucocytes in the histolytic phenomena of nymphosis. Metchnikoff and his pupils have shown that the white cell can eat up the most diverse kinds of microbian cells : this phagocytosis does not seem, however, to be a special and exclusive property of the white cell ; for example, though the histolysis of the tail of batrachians is attributed to leu- cocytes by Bataillon, it is attributed to muscular phagocytes by Metchnikoff and Soudakewitch; similarly, though Kolesnikoff, Weller, Babes, Valenza, Pugnat, Franca and Athias think that neurono- phagacis is the work of leucocytes, it is according to the statements of Krauss, Marinesco, Nissl, Anglade, and Rispal, caused by a neurogliac cell. Moreover all leucocytes are not phagocytes ; the small corpuscles are not, and the eosinophiles only slightly so. Now, are the cells absorbed by the leucocytes normal, or have they been previously altered ? It would appear that the answer is not the same for the animal and the microbic cell. In the case of the microbic cell, it seems there is no doubt that it may be ingested while alive, because even when thus digested ^ it still sometimes retains its power of killing. In the case of the animal cell, the problem is more complex, and the answer less easy. As a matter of fact, we should a priori, expect this phenomenon to depend either upon an anomalous exaltation of cytophagic activity of the white corpuscle, or upon a previous enfeeblement of, or the death of the phagocytic cell. The evolution of the process is often so rapid that histologically it is very difficult to determine the part played by these two factors respectively. On the other hand, a cell may be functionally weakened, and diseased, without this state of diminished resistance necessarily producing any morphological change. These considerations enable us to understand all the discussions which have been raised by the role played by phagocytes in the nymphal histolysis of insects or in that of the tailless batrachians : some maintaining that the cell disappears under the repeated efforts of the leucocytes : others, in fact the majority, asserting that the white corpuscles confine themselves to removing the residue from an organ which has already been altered. Without now entering into this question, we will simply remark that after studying the works of Loos, Eberth, Noetzel, etc., works which tend to prove that the solvent action of tissue juices and of blood is sufficient for this destruction, all the evidence goes to show that functionally at least GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 27 the cells thus digested are clearly in a state of inferiority owing to an arrest of their development, a considerable diminution or suspension of their nutritive changes, etc. But what do we find is the case in mammals ? If we leave on one side those epithelial cells which are casually destroyed by the migration of white corpuscles, we find that the latter attack the muscular cells in the course of infectious or toxic processes, and the red corpuscles in the case of the leuchaemias. This liaema- tophagic action of leuchaemic leucocytes allows us logically to assume hyperactivity of the white corpuscles, as well as a diminu- tion in resistance of the red. On the other hand, the myophagic action of leucocytes is more suggestive ; it shows that the muscular fibres are not digested, unless their nutrition has pre- viously been impoverished owing to a nerve lesion or the presence of a toxic agent. Admitting these facts, and admitting those observed in the physiological atrophy of invertebrates and batrachians, we shall not be illogical in thinking that, if phago- cytes really do intervene in the processes of atrophy in general and of senile atrophy in particular, they only destroy cells which are already on the brink of ruin. Reproduction. Leucocytes reproduce themselves by direct divi- sion (amitosis) and by indirect division (karyokinesis). Arnold thinks he has found in the more or less filamentous arrangement of chromatin elements in certain leucocytes, a proof of the existence of a mode of division which is intermediate between direct and indirect division. But Flemming and Reinke are of opinion that it is a question either of indirect multipolar divisions, or else of figures altered by reagents. Leucocytes can divide in the blood, the lymph, the connective tissue, the haematopoietic organs, in the lymphatic glands, the spleen, and in the medulla of bones. As a general rule, and with exceptions, which generally are pathological, we may say that the more numerous, and the better developed the haematopoietic organs, the less numerous are the divi- sions of white corpuscles in the circulation. For example, in the case of invertebrates, Cuenot found few or no divisions in the leucocytes of cephalopods, or of crustacean decapods, which possess lymphatic glands ; divisions are, on the contrary, frequent in the circulating white corpuscles of the pulmonates, the gasteropods, the orthoptera, the araneids, the solifugae, the oligochetae, and leeches, which have or appear to have no lymphatic organs. There are exceptions : thus the lamellibranchs possess lymphatic 28 THE LYMPHATICS glands, and though Apathy, de Bruyne, and Cuenot have seen mitoses : Knoll, Owsjannikow and Carazzi have seen amitoses on their free corpuscles. Similarly, among the vertebrates, and even in the mammals, where however the haematopoietic centres take on at certain times such an extraordinary development, it is possible to observe the division of white corpuscles wandering in the blood, the lymph, the connective tissue, and foreign bodies (pith of elder). In the blood, we may find mitoses, or direct division. It was in the blood of the axolotl that Ranvier observed the direct division of leucocytes ; and in the blood of the same animal that Lavdovsky found mitoses. Hemming doubts the accuracy of the observations of this latter author. Klein and Lowit have observed divisions in the blood of the triton. Mitoses have been noticed in the blood of the dog, rabbit, human embryo, and infant by Kultchitsky, Spronck and Prins, Wertheim, Hock and Schlesinger. Roehmer also admits the possibility of the reproduction of leucocytes in the blood by one or other of the two modes of division ; again, this reproduction in the blood is admitted by MedwedeiT and Markewitsch : Wlaeff has observed it after splenectomy, and numerous authors have noticed it in leuchaemic blood. Gourevitch has seen karyokinesis in the blood after injection of abrin, and of ricin, substances which at first provoke hypoleuco- cytosis, and then hyperleucoc3 7 tosis. In the lymph of the thoracic duct, Lowit has observed mitosis ; I have observed numerous mitoses in leucocytes circulating in the cavernous spaces of the mesenteric gland of a rabbit into whose veins I had injected pilocarpin. The chromosomes of some of the white corpuscles were arranged in the shape of a crown ; which arrangement has also been observed by Kostanecki. Meves and Henneguy have shown that this arrangement was due to the per- sistence of the sphere of attraction at the centre of the figure, and that in the Salamander, it involved the formation of the annular or perforated nucleus of the spermatogens. We may suppose that certain annular nuclei of leucocytes have a similar origin. In the cerebrospinal fluid from a case of general paralysis, I have seen the direct division of the nucleus of some small white cor- puscles which possessed no granules. In the peritoneal serous fluid of Lacerta viridis, Jolly has noticed mitoses. Peremeschko, Kultchitsky, Muskabluth, Metchnikoff, Flemming, Giovannini, Dekhuysen, Van der Stricht, Denys, and GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 29 M. Heidenhain have described the mitoses of wandering cells of connective tissue ; Arnold and Marchand those of leucocytes which had migrated into a fragment of the pith of elder (?). The mitoses observed by Heidenhain and du Bruyne, in the white corpuscles which infiltrate the intestinal epithelium, are not ad- mitted by Nicolas. In the normal state, in mammals, the repro- duction of free white corpuscles appears then quite certain ; but as regards the blood it does not appear to be so frequent as certain writers would have us believe. As a matter of fact, Spronck and Prins counted 18 mitoses in 9653 leucocytes in sections of the vena cava of the rabbit, and 2 mitoses in 1901 leucocytes of human blood obtained by digital puncture. Now Lowit counted 5000 white corpuscles without rinding a single kinesis. This author maintained that leucoblasts always divided directly ; and the erytho- blasts indirectly ; but Denis and Van der Stricht have proved the reality of the mitosis of leucoblasts. It was also believed that the polynuclear cells divided directly ; and the mononuclears, indirectly. It is now, however, demonstrated that the polynuclears, like the eosinophiles, show karyokinesis. The one or the other mode of division should not therefore be regarded as the exclusive property of any particular variety of leucocyte. On the other hand, amitosis seems, if not to exist exclusively, at any rate to predominate largely in the pulmonates, oligochetae, and leeches ; while kinesis predominates in the orthopterae (Heidenhain), and in the solifugae. Again, amitosis seems to be more frequent in the axolotl than among mammals. There is no object in here describing the karyokinesis of leuco- cytes, which in general, presents no special features. Let us con- fine ourselves to remembering the possibility of anomalous kineses ; those in which the chromosomes are arranged in the form of a crown about the centrosome, and which produce certain perforated nuclei ; those with multiple poles which, unaccompanied by protoplasmic division, give rise to multinuclear cells. Van der Stricht, who like Heidenhain, does not admit any connexion between the polymorphism of the nucleus, and its direct division, thinks with van Bambeke and Kostanechi, that certain poly- morphous nuclei result from the fusion of several smaller nuclei. The amitosis of leucocytes, described by Ranvier, Bizzozero, and Arnold, will engage our attention longer. Ranvier has stated that at a temperature of 16 a white corpuscle of axolotl requires three hours 30 THE LYMPHATICS for its direct division. In ordinary direct division, the nucleus is seen to divide into two segments or buds, of nearly equal size, bound by a pedicle which, becoming thinner and thinner, finally breaks. The division of the protoplasm soon follows that of the nucleus. It is quite evident that if the division of the protoplasm does not take place, there results a multinuclear cell (Arnold). It also happens that the buds do not detach themselves or fuse again (Ranvier). When the nucleus divides directly into several unequal fragments, we can witness the process which has been described by Arnold under the name of fragmentation. Arnold thought that some relation might exist between this fragmentation and the production of certain perforated nuclei. Goeppert thought that the perforation of the nucleus was a secondary phenomenon, and resulted from an invagination of the wall which deepened until it reached the opposite surface of the nuclear membrane. The annular nuclei, he thought, divided directly by constriction into two half rings which afterwards separated into many fragments, again by constriction. We may inquire what becomes of the centrosomes in direct division ? Flemming, stating that in the leucocytes of the salamander, the centrosome does not divide into two, thinks that the attraction sphere exercises an influence upon this division, for it is always placed opposite to the line of separation of the two portions of the nucleus. What is the significance of the amitosis of Ieucoc3^tes ? Flemming thinks it is a phenomenon of degeneration which, most frequently, increases the surface of the nucleus while producing multinuclear cells. Zieyler and von Rath express an almost analogous opinion : namely, that when direct division takes place both in the nucleus and protoplasm, the daughter cells cannot subsequently divide. Lowit, on the contrary, is of opinion that by the side of this direct degenerative division, there is a direct regenerative division, follow- ing which cells may continue to multiply. This histologist is of opinion that the richness of the nucleus in pyrenin or chromatin is variable ; a nucleus rich in pyrenin divides directly, a nucleus rich in chromatin indirectly. Henneguy thinks that nuclei which divide directly are no richer in pyrenin than in chromatin. Evolution, Degeneration, and Death. Of the ancestral protoplasms with free and independent life, the leucocytes have preserved, in spite of adaptations necessary to new conditions of existence in cellular colonies, not only their sensitiveness, their motility, their powers of digestion and reproduction, but even their individuality, GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 31 and their remarkable resistance to destructive agencies. Twenty-four hours after the death of the human body, the greater number of leucocytes are still living and can, under favourable conditions, keep alive much longer (Verworn). Recklinghausen and Ranvier have shewn that they are capable of retaining their properties outside the organism, sometimes for a very long period, viz. 22 days. It is difficult to know, even approximately, the duration of the normal life of a leucocyte. Everard, Massart and Demoor suppose it to be very short. Yet it may be fairly long, at least in the case of the aged. As the white corpuscles in the case of the aged do not appear to divide in the blood, or in the atrophic haematopoietic organs, Ave may admit, if not their permanence, at least their power of living a more or less long life. Nevertheless, either spontaneously or u n d e r d i ff e r e n t physical or chemical influences, leucocytes may degenerate and - %\ /?) \&b} ( ( )1 die. The degenerative { ^ J changes are numerous. *" IG - 3. Degeneration of leucocytes : hyperchromasis T , and fragmentation of nucleus (chromolysis) ; vacuoliza- 111 SOme Ot the aiiae- t ion and hypochromasis of nucleus. mias, Hayem mentions the surcharge of haemoglobin from certain mononuclears ; other cells become infiltrated with fat, glycogen and pigments (see Chemical Constitution). Czerny and Grigorjeff think the leu- cocytes may become infiltrated with amyloid material ; but this fact is contradicted by Obrzut. Ziegler describes a mucoid degen- eration of these elements. Heidenhain, Arnold, and Gunprecht have studied the chromolytic degeneration of leucocytes. The chromatin network becomes con- densed, forming a compact and homogeneous mass which breaks into fragments : balls are thus formed which, after the rupture of the nuclear membrane are scattered throughout the protoplasm ; the latter after swelling up and becoming vacuolated finally dis- appears, dissolved in the surrounding liquids. The nucleus thus altered is at first more readily stained than in the normal state, elsewhere it is pale, and its contour ill-defined. This last form of degeneration, described by Klein under the name of " leucocyte shadow," is perhaps artificial. Ranvier questions if leucocytes 32 THE LYMPHATICS which are destroyed at the site of a lesion during the process of repair, do not thus furnish nutritive material to the tissues during the process of rebuilding. T. Botkine, Engel, Borissoff and Kheta- gouroff have studied the histolysis of the leucocytes in blood. Bot- kine has even supposed that many of the varieties of leucocytes met with are only different stages of their disintegration in the plasma. In addition to this total histolysis there is a partial destruction by means of which the white corpuscle causes the disintegration of some of its granules or a portion of its protoplasm : this physiolog- ical degeneration has been described by Ranvier under the name of clasmatosis, and is regarded by him as a kind of secretion. Other leucocytes perish in this manner owing to a kind of continual wear of parts of their protoplasm against each other. Jolly thinks that, fre- quently eosinophile granules which have been suddenly separated from each other, and scattered over a fairly large surface (Klein) can join together again ; in such cases there would be an appearance of, but not a true destruction of the leucocyte. In all protoplasmic elements, in the Rhizopods for example, white corpuscles always die when they contract, that is to say when they assume a nearly spherical form. During the process of decomposition of the protoplasm, pale expansions shoot out which festoon its borders : these excrescences become detached in the form of clear, homogeneous, smooth balls (balls or sarcodic excrescences of Dujardin) and disappear without ever again returning to the cellular body. This process must not be confused with the formation of pseudopods. Leucocytes, when destroyed by physical agents (electricity, heat) assume a round form. Amongst chemical substances, water and acetic acid attack their nucleus, then cause the protoplasm to swell, and eventually kills them. Carbonic acid gas makes them lose all their staining qualities ( Yegorovski). The bases (ammonia, soda, and potassium) cause the nucleus to disappear, and little protoplasmic vacuoles to appear. Iodine destroys them, and colours them a greenish yellow : it causes the appearance of colourless or slightly violet sarcodic excrescences. Peptone does not destroy (Tchistovitsch and Schultze), but dis- solves them (Botkine, Delezenne). II. THE DIFFERENT LEUCOCYTES There are numerous classifications of leucocytes. We will recog- nize the following varieties : GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 33 (1) Microcytes (lymphocytes of Einhorn, Ehrlich). (2) Macrocytes (large mononuclears). (3) Cells with neutrophile granules (neutrophile cells). (4) Cells with acidophile granules (eosinophile cells). (5) Cells with metachromatic basophile granules (cells of Ehrlich). Before approaching the study of each of these varieties it is essential to point out the different classifications which have been proposed. From their study and criticism, we shall justify the nomenclature Avhich we suggest. HISTORICAL SKETCH OF THE CLASSIFICATIONS. Leuwenhoek (1722), Delia Tore (1776), and Mascagni (1780), saw rounded corpuscles in the lymph. In 1770, Hewson discovered leucocytes in the blood, and some time afterwards Reeklinghausen, the migratory cells in the connective tissue. Several j-ears were to elapse before the attention of histologists was drawn to the different varieties of white corpuscles. It was in 1845 and 1846 that Virchow, when studying leuchaemic blood, distinguished two kinds of leucocytes ; one, the more numerous, were large ; others were small and almost with- out protoplasm. He inquired into the signification of these different cells : at first he thought that they were separate elements with different origins. Later on he came to the conclusion that they represented evolutionary and functional stages of the same element. Since then, experiments have multi- plied, methods have been perfected, and theories freely advanced, but the problem proposed long ago by the author of Cellular Pathology has not yet been definitely solved. In 1846 Wharton Jones recognized that amongst leucocytes, some were granular, and others were not. This observation has retained its importance in contemporary classifications, all of which under different titles, are based upon the very complete work of Max Schultze in 1865. In taking as a basis for classification their dimensions, the shape of their nucleus, the presence of granules, this histologist distinguished four kinds of leucocytes, which he called 1, 2, 3 and 4 varieties. The first variety comprises cells which are smaller than red blood corpuscles, and which are almost destitute of protoplasm; the second, larger cells, with more abundant protoplasm, and a rounded nucleus ; the third, more numerous cells, with very finely granular protoplasm, with a single or multiple nucleus; the fourth, cells with coarse refracting granules: thus with the exception of the cells of Ehrlich, Max Schultze recognized .all the varieties of leucocytes. Hayem's classification is very similar to that of Max Schultze, but a new observation was however made, for the French haematologist described two kinds of non-granular cells : one having clear protoplasm, the other, opaque coloured protoplasm. The old histologists, as may be seen, refrained from giving names to cells which they studied, but this reserve has not been observed by their successors. These names are either in accordance witli the dimensions of the cell, the form of the nucleus, the nature of the granules, or in accordance with the presumed origin, or probable age of the white cell ; sometimes again the names given suggest one of its physiological properties. Compromises have been established between terminologies founded on these different principles, and it may be said that the extreme difficulty of reading books of haematology is the least of the inconveniences caused by this system of nomenclature. 34 THE LYMPHATICS According to their dimensions and the shape of their nuclei, Lb'wit dis- tinguishes amongst the white corpuscles : 1. small mononuclears. 2. large mononuclears. 3. leucocytes with polymorphous nuclei. 4. polynuclears. This terminology, which is still largely used to-day, has been the subject of criticisms, both numerous and well founded. Ranvier, Flemming, and Heidenhain. having shown that the leucocyte called poly nuclear was almost always a cell with a polymorphous nucleus, it became necessary to proscribe the term as being inaccurate, though unfortunately it is still sanctioned by usage. Again, as Metclmikoff has observed, it is just those cells which are called large mononuclears which as a matter of fact sometimes have two or three perfectly distinct nuclei. This scientist has given the name of macro phages to these large mononuclears, a name which while it involves no theories as to their origin, or the necessarily variable appearance of their nuclei, has the advantage of reminding us of their size, and their re- markable phagocytic properties. The other leucocytes (eosinophiles, cells with neutrophile granules) are called micro phages. Such a terminology is not without inconvenience from the histological point of view ; for it in- cludes under the generic term of macrophage, elements of widely different origin and significance, viz., leucocj'tes, eiidothelial cells, neurogliac, and nervous cells. Neither does it do away with the necessity for using other terms to denote the different microphages, and for those white corpuscles which are not phagocytic. Ouskoff classifies leucocytes as young, mature, and old according to their age. The young are the small and large lymphocytes, and the small transparent corpuscles. The mature are the large and lobulated transparent corpuscles, and the transitional forms, small, large, and lobulated. The old the mononuclears, and the polynuclears. In this system the eosinophiles are not included in any of the divisions established by the Russian histologist. It is quite clear that the small mononuclears much resemble young cells and even embryonic cells. It is more difficult to admit the senility of the large mononuclears; and of the polynuclears ; their amoebic and their phagocytic properties afford too much evidence of their powerful vitality. Ehrlich describes six normal kinds of leucocytes ( 1 ) Lymphocytes. (2) Large mononuclears. (3) Transitional forms. (4) Polynuclears. (5) Eosinophiles. (6) " Crammed cells" (Metclmikoff thus translates the expression, " Mas- tzelleii"; they are also called "fattened cells." " Stuffed cells " is perhaps more accurate. In addition Ehrlich admits four anomalous forms. (1) Neutrophile mononuclears (neutrophile myelocytes). (2) Small neutrophile pseudo-lymphocytes. (3) Eosinophile mononuclears (eosinophile myelocytes). (4) Irritation form of Tiirck. It will be seen apart from the term lymphocyte (Einhorn), that Ehrlich, retains the terminology based on the appearance of the nucleus : but now that it is recognized that the lymphocyte is found not only in lymphoid organs (glands and spleen), but also in the marrow of bones (Dominici, Pap- GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 35 penheim) it seems that there is no advantage in substituting this term for that of small mononuclears. The transitional form may perhaps be described with the large mononuclear. And since the irritation form of Tiirck appears to represent a nucleated red blood corpuscle (Ehrlich, Engel), it is useless to retain the term here. The existence of this cell will suffice to prove how delicate is the distinction between a white and a red cell. Though the eosinophile mononuclears constitute abnormal elements in human blood, they are constant in the blood of the pig and in that of the horse. They cannot be called eosinophile myelocytes seeing that they are some- times formed in the lymphatic glands and in the thymus. Notwithstanding its clearness, there are a great many objections to Denys's classification. This author lays down that all non-granular leucocj^tes are derived from lymphoid tissue ; he mixes them up under the name of lymphocytes. All the granular leucocytes ccming from the marrow of bone, are called myelocytes. Whatever may be the dimensions and shape of their nuclei, these myelocytes are acidophile, basophile, neutro- phile, according to the nature of their granules. It is unfortunate that the brilliant simplicity of this conception accords so ill with the facts. First of all it takes for granted, what is far from being demonstrated, namely that leucocytes cannot originate except from bony marrow or lymphoid struc- tures, and it does not even refer to the possibility of their origin from connective tissue. Now the white corpuscles are very constant formations in the animal series, and in the aged, and we might almost say, commonly found in all many- celled beings. In phylogenesis as in ontogenesis, they exist before the appear- ance of the haematopoietic organs. Whether they are of mesoblastic or entodermic (vascular endothelium) origin, some of them bear a strange resemblance to the fixed elements in connective tissue. These resemblances are such that even now there is much discussion as to whether the plasmatic cell of Waldeyer, and Unna, arises from connective tissue or from leucocytes. Whilst Unna, Menahem and Hodara uphold the connective tissue origin ; Jados- sohn, Marshalko and Dominici support the leucocyte origin (lymphocyte). On the other hand, the cells of Ehrlich (the fattened cells), which have been separa- ted from the group of plasmatic cells on account of their metachromatic gran- ules, are often more numerous in the connective tissue of viscera than in bonv marrow. Moreover, in the fin of the tadpole, Metchnikoff has observed all transi- tions between the connective tissue cell and the white cell. Further, knowing that the fixed cells are not phagocytic and finding foreign substances within some of them, MetchnikofT concluded that the latter were old phagocytes which had become fixed. Finally, the splendid researches of Ranvier have shown that the clasmatocytes are fixed leucocytes, capable of movement. It is there- fore quite certain that there is an intimate analogy between the connective tissue cell and the white cell ; it is proved that a leucocyte can become a connective tissue cell, and it is at least very probable that a connective tissue cell can become a white cell. The majority of anatomo-pathologists admit that the embryonic connective tissue cell, which morphologically so resembles a young leucocyte is capable of movement, and therefore of physiologically resembling it. Numerous observers having seen wandering leucocytes divide in the con- nective tissue meshes, it is certain that these elements can reproduce them- selves elsewhere than in the large lympho-medullary centres. Leucopoiesis, like haematopoiesis, appears to be an elaboration of many stages, varying according to the zoological species, and probably according to the age of the individual. 36 THE LYMPHATICS If we admit the lympho-medullary centres to be the sole sources of origin, and yet reject as improbable, the permanence or the reproduction of free ele- ments in the blood plasma, the lymphatic, or the connective tissue systems ; then it is very difficult to understand how blood renovations take place in the aged. A definite though intermittent leucopoiesis of connective tissue origin would perhaps furnish a more satisfactory explanation of this phenomenon. We may now incjuire what objections can be raised to the theory which, while it distinguishes two kinds of leucocytes, places the origin of some in the marrow, of others in the gland. This theory takes for granted that the various leucocytes bear no relation to each other : a point on which there has been much controversy. Though it is not certain that transitional forms between the various granules exist ; and though in the blood and lymph forms of transition between the granular and non-granular cells are few in number, and not sharply marked, the case is other with the haematopoietic organs. Here it is both possible and easy to see the white cell acquire granules. Now while the bony marrow normally possesses non-granular cells which, whether small or large, are identical with those of the tymphatic gland, the latter can present in the normal state all the granular cells which are regarded as belonging exclusively to the bony marrow. But it has been argued, the presence of cells in the gland does not necessarily mean their production there : these wandering elements, which are produced else- where, become fixed there by unknown influences. It must be admitted that this objection may be raised against those authors who maintain that the marrow is the site for the formation of eosinophiles, and of the cells loaded with fat, cells which are far from presenting numerous mitoses in it. But eosinophiles exist in lymph ; and sometimes, even in the gland itself, they show indisputable signs of cytodieresis ; sometimes again they possess but one nucleus, and a few granules. Finally their numbers increase in pathological hypertrophies or diseases of the lymphatic gland, in lymphaclenoma, and after splenectomy. It is very possible that this last mentioned eosinophile springs not only from the gland, but also from the marrow. The latter is then hyperactive. The substitution of the spleen by an antagonistic organ, is not easily intelligible, but it becomes so, if we assume that the marrow, the spleen and the glands are structures which were originally identical, differing more in appearance than in reality, and always ready to manifest their former energies. We know that in certain animals a single organ is quite sufficient to perform the duties which normally fall upon the marrow, the spleen and glands. A long time ago, Renaut and Metchnikoff observed that cyclostomes removed from the marrow of bones possessed eosinophiles. On the other hand, the aged in spite of the func- tional disappearance of the marrow, which has long since been invaded by fat, possess both eosinophiles and neutrophiles. How can we term myelocytes, cells which pre-exist and survive the organ considered as their only source of origin ? How can we call lymphocytes, cells which exist in the marrow as well as in the spleen, or gland ? In reality, even in the higher vertebrates, both the marrow and the gland preserve the imprint of their original fusion : there is no cell called myeloid which cannot exist in lymphoid organs, and inversely ; on the contrary, many morbid influences can satisfactorily show this symbiosm of two lympho- medullary formations, a symbiosm which is also well proved by normal and comparative histology. Dominici has related many cases of this nature, and has grouped them under the name of myeloid transformation of the spleen. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 37 If for all these reasons we find we have to sacrifice the terms, lymphocytes and myelocytes, it is well to remember that Denys is quite right in not making the form of the nucleus the basis of his classification, but simply classifying the granular cells according to the nature of their granules. Without repeating all the drawbacks of L6 wit's terminology, we may remark again that the shape of the nucleus represents a functional state, which in the most various kinds of cells is sometimes identical, and in a differ- ent way represents the distinctive sign of a definite cell species. In other words, cells of the same species, the eosinophiles for example, present different nuclei (single or double) according to the animal considered, and according to the part from which they are taken, etc. ; inversely, cells which vary in size, physiological properties, such as the lymphocytes and the large mononuclears of Ehrlich, each have a single rounded nucleus. Microcytes Synonyms. First variety of Max Schultze, globulins, free nuclei of Robin ; nuclei of origin of Pouchet ; lymphocytes of Einhorn and of Ehrlich ; small clear and opaque mononuclears of Hayem ; young leucocytes of Ouskoff ; small lymphatic corpuscles of Engel : leucoblasts, primary leucocytes, small lymphocytes of Denys ; small hyaline cells of Gulland. These are cells whose dimensions are equal to, or smaller, or slightly larger than those of red blood corpuscles ; the diameter of the smallest is from 5' 5 /JL to 6 /z ; that of the largest (the medium- sized mononuclears of Malassez) varies between 7"5 ;/, and 8 JJL. It is al- most impossible to ac- curately fix the higher limit because, as regards size, we find all inter- mediate sizes exist be- tween the leucocytes and the macrocytes. Rounded, oval, and sometimes polygonous, these elements possess a relatively large central nucleus, partly surrounded by a fine protoplasmic border, which it is frequently very difficult to see ; this had escaped the observation of certain histologists who described these elements as free nuclei. The protoplasm is, proportion- ately to the nucleus, much more developed in the medium-sized elements (the medium-sized mononuclears of Malassez). This layer of protoplasm is somewhat irregular, and presents thickenings shaped like a cap ; its external surface often bristles with points, or with detachable buds. The protoplasm is more refracting than D FIG. 4. Microcytes and Macrocytes. 38 THE LYMPHATICS the nucleus. At one time it is like mother-of-pearl, colourless or light, at another opaque or coloured (Hayem). It may, on the other hand, appear homogeneous or very finely granular. (We are now dealing with cytoplasmic granules which have probably no con- nexion with the granules of leucocytes properly so called.) It has an alkaline reaction (Ehrlich). It maybe (1) faintly stained, or slightly basophile ; or, (2) strongly basophile, more so even than the nucleus. According to Hayem, the protoplasm of the small opaque mononuclears of human blood can be indiscriminately stained : it takes an intense stain with eosin or orange ; it turns a greenish tint with methylene blue, and purple with thionin. Elsewhere, the same author states that the opaque mononu- clears in horse's lymph are especially basophile. The nucleus is rounded ; and may present, especially in the largest forms, a lateral depression (Ehrlich) ; when this indentation increases, the nucleus becomes polymorphous. After fixation by heat, and staining with the triacid, the nucleus appears almost homogeneous, greenish or bluish black (Engel). By means of other fixing agents, we can distinguish the presence of granules, or masses of chromatin in the centre or in the periphery ; the central chromatin either appears elongated,or looks like a rounded corpuscle : the peripherally placed chromatin forms a nuclear mem- brane which is thick in some places, and thin in others. Sometimes, but not always, these cells possess one, or even two, true nucleoli, which are clearly brought out by fixation with chloride of platinum (Lowit). They may also be seen after fixing with sublimate, and staining with orange-haematoxylin. In fact, all these cells have sufficient common characteristics to constitute, in appearance at least, a natural family. But side by side with these resemblances (small size, scantiness of protoplasm, an almost identical arrangement of nuclear chromatin, etc.), there are differences in their optical properties, in the staining affinities of their protoplasm, and in the outline of their cells which is sometimes regular, sometimes irregular. These differences are, in Hayem's opinion, sufficiently important to justify a distinction into two classes of cells : viz. the clear and the opaque mononuclears ; the latter correspond to the lymphocytes of Ehrlich ; they are met with only in the lymph ; consequently this term, which indicates their origin, is very reasonable. Dominici makes further distinctions. He describes, by the side of the ordinary lymphocyte, with a deeply stained nucleus, dotted both centrally and peripherally with GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 39 granules of chromatin ; with slightly basophile or clear proto- plasm, identical elements, whose only special characteristic is their power of emitting protoplasmic buds which can detach themselves. He gives to this physiological stage the individuality of a cellular type which he defines as the mother cell of globulins. Then, under the name of small plasmacell, he describes a cell with a deeply stained nucleus, and extremely basophile protoplasm ; under the name of small basophile mononudear, he describes an element with homogeneous and extremely basophile protoplasm, but whose nucleus is clear, and almost destitute of chromatin. We know that even the same cell, according to the state of its nutrition, its repose, and the mitosic activity of its nucleus, shews considerable variations in its nuclear chromatin contents and in its staining properties ; and we also know that the staining reactions of protoplasm may vary in the same element, according to the phases of its evolution ; in short, the power of detaching small frag- ments of their protoplasm into the surrounding media is a very common property of leucocytes. We may therefore suppose that the mother cell of globulins, the little plasmacell, and the little nuclear basophile are not so much true cellular types, with special characteristics and individualities, as phases of the same element, which vary with the state of its evolution, nutrition or degeneration. The microcytes are not phagocytes (Metchnikoff) , Their amoebic properties, which are altogether denied by some authors, seem limited ; but they exist nevertheless (Laguesse Wolff, Hirschfeld) ; they are perhaps inconstant (Jolly). The microcytes are met with normally in the blood, the lymph, the serous fluid from the peritoneum, in diffuse or circumscribed lymphoid formations near the epithelium, especially that of the digestive tract, in lymphatic glands, in the spleen, and in the marrow of bones. In the blood, out of 100 white corpuscles, there are from 22 to 25 microcytes (Ehrlich and Lazarus) ; Ouskoif finds 20 to 25 ; Mathias Duval 23 ; and Dumont 28- 5 out of every 100. They are more numerous in young children (Voino-Oranski, Ehrlich, Engel), less so in old people, from 75 and upwards (especially rare in old people of 90) (Solovieff) : they increase during lactation (Ostro- gorsky), during digestion (Rieder), after injection of pilocarpin (Waldstein, etc.), after splenectomy (Uskow, Emilianoff, Hartmann and Vaquez). In the latter case, Koroboff has seen them dimin'sh. They increase under most varied morbid causes, viz. lymphade- 40 THE LYMPHATICS noma, malignant lymphomas (Ehrlich, Karewski), in the deteriora- tion of blood accompanying tuberculosis (Grawitz), in whooping cough (Meunier). They diminish after extirpation of the pancreas of Aselli (Rokitzky, TchigaiefT) ; after the extirpation of several important groups of glands, Ehrlich and Reinbach found 0'6 in every 100, instead of 25 for every 100. Koroboff observed their diminution after ligature of the thoracic duct ; Omelianski, after section of the vasomotors. These elements are most numerous in the lymph : Hayem found in the lymph taken from a lymphatic vessel running by the side of the carotid artery, only " opaque inononuclears." In the thoracic duct of the dog, out of 133 elements I found 128 micro- cytes. After fixation with sublimate, their protoplasm stained well with acid colours. They predominate also in the cavernous pas- sages of the lymphatic gland. Though they are usually regarded as very young elements by some authors, others look upon them as old and degenerate cells which have lost their protoplasm. When compared with other leucocytes, it is interesting to observe that in certain pathological circumstances, they may, without any increase in size, become charged with neutrophile granules (Rieder). They then become the "small pseudo-lymphocyte neutrophiles " of Ehrlich. In the same way, the eosinophile microcytes are sometimes found in the normal lymphatic gland. We must again insist on the fact that there are no precise limits, in regard to size, between these elements and those which we are about to study under the name of macrocytes. Macrocytes Synonyms. The second varietj' of Max Schultze, the large kinds of clear and opaque mononuclears of Hayem ; certain macrophages of Metclmikoff : certain vacuolated cells of Renaut and Lacroix ; megalocytes of Dumont ; polyeidocytes of Darier ; large mononuclears of Lowit, Ehrlich ; large lymphocytes of Denys, Engel ; mature and old leucocytes of Ouskoff ; large hyaline cells of Gulland. The Macrocytes are rounded or irregularly oval, and in the blood range from 15-17 p ; in the tissues from 30-40 /u,. They are the largest leucocytes. Their protoplasm is abundant and often presents vacuoles ; it stains more feebly than the nucleus and appears slightly basophile (Ehrlich). The protoplasm of macrocytes which has been studied in the tissues (lymphoid tissues) is either extremely basophile or acidophile. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 41 The nucleus is large, rounded, or nearly quadrangular ; it is also found to be reniform, cordiform, or shaped like a sac ; it is some- times double or even triple : thus these cells are genuinely poly- nuclear. The nucleus, which is nearly always eccentrically placed, is somewhat pale, and presents one or two true central nucleoli and some chromatin granules ; the chromatin network is very delicate and disappears readily in sections which are badly fixed. It is quite clear that we cannot agree with Botkine that the form and dimensions of these cells entirely depend upon artificial altera- tions taking place in a mononuclear medium. Ehrlich does not include in the large mononuclear class, those elements in which the nucleus is reniform ; and as he finds in their protoplasm some neutrophile granules, he describes them under the name of intermediate forms, i.e. intermediate between non-granular leucocytes with a rounded nucleus, and granular leucocytes with a polymorphous nucleus. It has been remarked that these inter- mediate cells are larger than the polynuclears, and that they are rare in the blood ; Ehrlich, however, does not admit the existence of intermediary forms between his lymphocytes and his large mono- nuclears. Here, we find again the large opaque and clear mononuclears of Hayem. The large opaque mononuclears are always smaller than the clear mononuclears. If, as Hayem thinks, there are no intermediate forms between the clear and the opaque, all the intermediate forms exist between the large and the small forms of each of these two series. The macrocytes are amoebic, and extremely phagocytic. They digest the bacillus of Hansen, red corpuscles, leucocytes, and par- ticles of the sulphate of arsenic (Besredka). They exist in the blood, the lymph, the peritoneal serous fluid, the connective tissue, lymphoid formations, lymphatic glands, the spleen and the bony marrow. In the blood, out of 100 leucocytes, Ehrlich counts 1 large mono- nuclear, 2 to 4 transitional forms ; Dumont finds 1*5, and Hayem 13. per cent. This difference is evidently accounted for by the fact that these authors have not adopted the same arbitrary line of demarcation between the micro- and the macrocytes. In the lymph, Hayem found only large opaque mononuclears. In that of the thoracic duct, Dominici found macrophages and basophilic myelocytes. In the thoracic duct of the dog, I have found some macrocytes with a reniform nucleus. I have also seen a fair number of vacuolated and non-vacuolated macrocytes. D * 42 THE LYMPHATICS whose protoplasm almost always proved to be acidophile in the lymph spaces of the normal gland of the rabbit. These elements increase in leuchaemia, mycosis fungoides (Bensaude, Leredde), malaria, and after section of the vasomotors (Omelianski). Cells with Neutrophile Granules Synonyms. Third variety-of Max Schultze and Hayem ; polynuclear, leucocyte, or rather leucocyte, with a polymorphous nucleus ; one of the micro- phases of Metclmikoff ; old leucocyte of Ouskoff ; cell of Kanthack and Hardy with fine oxyphile granules ; neutrophile myelocytes of Denys. These cells which range from 10 to 14 ^ in normal blood, are easily recognizable by the well marked poly- morphism of their nuclei. In the blood of certain leuchaemic cases and in the marrow of bones, there are larger cells with neutrophile FIG. 5. Cells with neutrophile granules. granules, and a round- ed nucleus ; it is for these only that Erh- lich has reserved the name of neutrophile myelocytes (neutrophile mononuclears). It is only in exceptional cases, that cells as small as microcytes possess neutrophile granules (dwarf corpuscles of Spilling, Rieder and Jolly ; small neutrophile pseudo-lymphocytes of Ehrlich). The polymorphous nucleus is con- stricted into two parts, and twisted in a variety of ways so that it more or less resembles the letters E S Y Z. It is often composed of 2, 3 or 4 rounded masses, or twined stalactiform figures, but more usually it is made up of chro- matiii filaments so fine as to be almost imperceptible. This nucleus is, in turn, moniliform, star-shaped, and bud-shaped. We have seen that many causes appear to take part in the genesis of these capri- cious forms. Without here re-enumera- ting them all, we will simply add that it very frequently happens, as has been shewn by Denys and Jolly that the annu- &&:& m & FIG. 6. Annular and semi- annular nuclei. Those in the first row may perhaps be ex- plained by supposing an anomaly of karyokinesis (crown-like ar- rangement of the chromosomes) ; an incomplete fragmentation may account for those in the second row. The others arise from the approximation of the two ends of the tube-shaped nucleus. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 43 lar form, whether complete or incomplete, arises not from a caryo- dieretic anomaly, but from the simple junction of the free extremities of the arciform nuclear mass. This nucleus possesses a network of strong dense chromatin ; it is coloured greenish or bluish black by the triacid. The single nucleus (myelocyte or neutrophile mononuclear of Ehrlich) is large and is perforated by holes through which the cytoplasmic granules may be seen. The protoplasm, which is very refracting, stains well with the acid stains (Ehrlich). It is dotted with fine granules, which are coloured violet by the triacid (mixture of methyl green, orange, and acid fuchsin). These are the granules which Ehrlich calls neutro- philes. We have already alluded to the discussions which the staining affinities of these granules have provoked. They are soluble in distilled water, potash, and in acetic acid (3 in 100). The cells with neutrophile granules are very amoebic, and very phagocytic. Like other leucocytes they can reproduce themselves by mitosis. They are found in the blood, but much more rarely in the lymph. They are rare in the glands and in the spleen, but in the marrow of bones they are again much more numerous. They form the majority of the white corpuscles of the blood : 70 to 72 in 100 (Einhorn) ; 70 to 80 in 100 (Ouskoff) ; 75 in 100 (Ehrlich and Lazarus) ; 60 in 100 (Jolly) ; 66 in 100 (Leredde and Bezanon) ; 67 in 100 (Dumont). They appear to be less numerous in very young infants ; viz. 28 to 4.0 in 100 (Goundobine) ; 40 in 100 (Jolly) ; 40 to 50 in 100 (Besredka). In old subjects Jolly finds 70 in 100. They increase during digestion (Ouskoff, Leredde, and Loeper). They increase after various kinds of injections, and in certain intoxi- cations (abrin, ricin) (Gourevitch). According to Yegorovski they are more numerous in arterial than in venous blood. The introduction of oxygen into an arterial segment causes them to increase (Yegorovski, Markevitsch) : but the introduction of the same gas into a venous segment causes them to diminish. Under the influence of chloroform they diminish (Popoff) ; and the same thing happens with pressure (Vinogradoff). Though Hayem did not find them in the lymph of the horse, Dominici has seen them in that of the thoracic duct, and out of 133 leucocytes counted in a dog's lymph (thoracic duct), I have observed 3 of these cells. 44 THE LYMPHATICS Cells with Acidophile Granules Synonyms. Fourth variety of Max Schultze and Hayem ; leucocytes of Semmer ; alexocytes of Hankin and Kanthack ; Eosiriophiles ; Myelocyte Eosinophiles of Denys. The eosinophiles are as a general rule slightly larger than the cells with neutrophile granules, and have a rounded or a polymor- phous nucleus. Though it is normal to find only the leucocytes of Semmer with a polymorphous nucleus in the blood of the healthy man, the variety with the rounded nucleus exists in the blood of the healthy pig and horse (Hirschfield, Hayem). It is for this mononuclear type that Ehrlich reserves the name of eosinophile myelocyte. w,. '"!; $ ^\ f) The nucleus of the eosi- ej- - ^ nophiles in man is, as a .;.>, rule, a little less stainable "*SP/- -" v-'. than that of the neutro- Fio. 7. Eosinophiles with a single nucleus, and philes. Sometimes formed a polymorphous or multiple nucleus. Collection of , . , .. . ,, , granules ; histoiysis. of three, it is usually made up of two nearly equal rounded or oval masses, joined or not by a fine chromatin filament. Jolly lays stress on this arrangement, which has been figured, but not described by Hayem, Renaut, Hardy, and Wesbrook, and Klein, etc. This nucleus may be formed by an arciform mass almost identical with that of the neutrophile potynuclears. As it is fre- quently perforated the cytoplasmic granules may be seen. In the protoplasm are found more or less numerous, somewhat coarse, spherical, or more rarely oval granules, which are very re- fracting and have a pale yellow tinge. These granules are deeply stained by the acid stains, eosin, and especially by orange ; the periphery stains more than the centre (Ehrlich). With thionin, the granules are stained a clear green (Dominici). They are not stainable with osmic acid. They are insoluble in alcohol, ether, chloroform, essence of turpentine, sulphide of carbon. Unlike haemoglobin, and in spite of the fact that it contains iron, this granule, according to Barker, Lowit, Sacharoff, Tettenhamer, is insoluble in water (Schwarze, Robin, Malassez) and in glycerine. It is insoluble in oil of cloves, liquor potassae (3 in 100), acetic acid (which, by the way, is prejudicial to its ultimate stain- GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 45 ing), the alkaline bichromates, sublimate, formol, and chromic acid. By reagents de Reichl and Mikosch, Renaut and Weiss have established that it is of an albuminoid nature (globulin) ; and Siawcillo also finds in it some of the properties of the albuminoids : he finds it is stained yellow b}' nitric acid, red by Millon's reagent, and brown by the iodo-iodide solution. It is generally agreed that it is coloured yellow by the latter reagent. Is this difference to be ex- plained by the fact that Siawcillo studied the eosinophiles of the ray fish, and other histologists that of mammals ? On the other hand, its insolubility in gastric juice renders it akin to the nucleins. If it has been clearly shown that the eosinophile granules represent neither remains of cells, as Tettenhamer and Sacharoff thought, nor phagocyted microbes, as Metchnikoff and Mesnil asserted ; if, contrary to the opinion of Pouchet and Hayem, it can be shown it is not a question of haemoglobin, it is more difficult to understand what ends these granules serve, which, after being manufactured and preserved like reserves of vitellin, are finally collected together in the tissues. Hankin and Kanthack regard their substratum as being composed of alexin, a mysterious bactericidal substance. Altmann imagines that they are ozonophores which play a role in the oxida- tions of the organism ; Cattaneo, that they carry a ferment which is necessary for the assimilation of certain albuminoid substances. Wagner thinks they are necessary for the nutrition and formation of different eels. In opposition to Renaut's views, several authors (Max Schultze, BizzozerO; Hayem, Tschlenoff, Miiller and Rieder, Jolly) have upheld the existence of amoebic movements in the leucocytes of Semmer. Their phagocytic properties, denied by Hankin and Kanthack, have been demonstrated by Dolega and Mesnil : they are, however, limited. The eosinophiles exist in the blood, lymph, peritoneal serous fluid, the connective tissue (in the neighbourhood of salivary, gas- tric, intestinal, mammary and bronchial glands), in the lymphatic glands, the spleen, and in the marrow of bones. Whereas Michaelis considers there is a relation between the abundance of eosinophile secretions and the suppression of an external secretion (viz. mammary), Bonne has more recently maintained that the bronchial and eosinophile secretions take place simultaneously. 46 THE LYMPHATICS In the blood, Ehrlich reckons 2 to 4 eosinophiles for every 100 white cells ; Dumont, 2- 5 ; Leredde and Loepei\ 1 to 2 ; Engel, 2 to 3 ; Canon, 2. The last mentioned author found in infants T06, and 2-31 per cent, and in old subjects, 2- 09 ; and 7 (in a man of 88 years of age) per cent. Eosinophiles increase under the influence of pilocarpin (Neusser), and iron preparations, after splenectomy and in the most varied morbid conditions, viz. leuchaemia, cutaneous affections (pemphigus, pellagra, eczema, psoriasis, prurigo scheroderma, syphilis), vaccinia, helminthiasis, scurvy, blennorrhagia, tuber- culosis, scarlet fever, intermittent fever, asthma, emphysema, psychosis, neurosis. They diminish or disappear at the crisis of pneumonia (Bettmann, Engel), of typhoid, of rheumatism, of ery- sipelas (Bettmann). I have found some eosinophiles in the lymph of the thoracic duct of the dog (1 in 133), as have also Hayem and Dominici. Cells with Basophile Granules, Metachromatic, or Cells of Ehrlich Synonyms. Mastzellen of Ehrlich; isoplastic cells of Audry ; basophile myelocyte of Denys. These cells vary very much in size in different animals. They range between 8 and 12 p, in the case of mammals; and in batrachians the} r vary from 30 to 40 p. They are rounded, polygonal, elon- gated or even ramified ; in the latter case, their nucleus is sometimes central, sometimes polar ; they much resemble clasmatocytes. The nucleus, which is often masked by granules, is sometimes rounded, or * **^ more or less ovoid, or sometimes FIG. 8. Ceils of Ehrlich. in some polymorphous (bi- or trilobed) In of them, the granules are dissolved. ' it should be noticed how owing to the cells ol JMirlicli, taken from Ivm- ' P hatic 8 lands > J have constatly found a rounded nucleus somewhat like that of microcytes. It differs from it in its lesser staining capacities (Pappenheim). This nucleus is coloured pale blue by the polychromatic blue of Unna ; it has a fine membranous capsule, and some fine chromatin GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 47 granules. In the protoplasm are found granules whose form, dimensions, and distribution are irregular. Rounded or cocciform, these granules are sometimes finer than the eosinophiles, sometimes as coarse, sometimes even they are of larger size (Engel). In some cells, they are closely packed ; in others, they are further apart. These granules are soluble in distilled water, in acetic acid (3 in 100), and in Adam's fluid ; they are insoluble in alcohol, and in alcoholic ether. They stain with Gram and Ziehl ; also with dahlia, but, treated with carbonate of potash they become dis- coloured ; this is not the case with microbes. By analogy, it may be asked if these granules do not owe their resistance to decolorization by strong acids, to the presence of a fatty covering. In any case, they do not stain black with osmic acid. FIG. 9. Clasmatocytes of the triton (after Ranvier). With thionin, and Unna's blue, they yield a red, that is to say metachromatic tint, analogous to that of mucus but, more intense. They stain almost pure brown with extra-kresyl violet. Nordmann and Raudnitz think these granules are neither composed of amyloid material nor of mucus. Besides, if the metachromatic red is obtained not only with the granules of Ehrlich's leucocytes, but also with mucus, and with the fundamental substance of hyaline cartilage and Wharton's Jelly, it also manifests itself with the most varied chemical substances, (nitric and sulphuric acids, potash, chloroform, acetone, anilin, oil of cedar). It is not unusual to see Ehrlich's cells shed their granules around them ; sometimes the granules are set at liberty after having been previously dissolved in the protoplasmic body. 48 THE LYMPHATICS By their form, their mode of secretion, the cells of Ehrlich are very similar to those of Ranvier (clasmatocytes). In the batra- chians, the analogy is complete ; in mammals, there is one difference, viz. metachromatism does not exist in the granules of the clasmatocytes (Jolly). Does this difference justify us in making a Avide distinction between two elements which are similar in so many respects ? In the first place, it has not yet been proved that met- achromatism is a chemical phenomenon ; and even if we admit there is a difference of chemical constitution between the meta- chromatic basophile granules and the non-metachromatic, this difference does not seem sufficient to justify us in making a com- plete distinction between two orders of elements whose comparative anatomy shows them to have such intimate affinities. Besides, are not the red blood corpuscles of different animals morphologically and functionally identical, in spite of a very real difference in their chemical constitution ? The cells of Ehrlich exist in the blood, in serous liquids. 1 in the perivascular connective tissues of the great omentum, in the dermal papillae, in the submucous coat of the intestines, often in the con- nective tissue spaces of the liver, also in the lymphatic glands, the spleen, and the marrow of bones. They are very rare in human blood ; Ehrlich and Lazarus finding only 0-5 in 100 as the maximum, Canon 0'28 in 100. According to Canon, they are apparently more abundant in the blood of infants (0'88 to 1-86 in 100). Zollikofer has found them in larger numbers in the blood of subjects afflicted with sciatica, hysteria, and acute rheumatism. After the injection of pyrodin, Schmauch has seen them increase, as has Levaditi, after the injection of the toxins of staphy ococc'. In the blood of the rabbit, Bauer finds 2 to 5 in 100 ; Levaditi, 4*3 in 100. Now, these cells are without doubt very rare in the connective tissue of this animal. It is interesting to remark that Ehrlich's cell is as scarce in the blood, as it is abundant in the connective tissue. This is a law common to almost all the leucocytes of the higher normal vertebrates : thus the macrocytes and eosinophiles, which are rare in the blood, abound in the connective tissue ; and the microcytes and neutrophiles, which are found in quantities in the blood, are rare or are absent in the connective tissues. 1 Milchner has found several in ascites in a leuchaemic case, Xeisser in the exudate of a blennorhagia. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 49 Ballowitz has stated that the cells of Ehrlich are scarce in the connective tissues of the rabbit, the hare, the guinea-pig, and birds ; but that he has observed many in the dog, the calf, the goat, the rat, and the bat. In the latter case, he has found them as numerous after, as before hibernation. On the contrary, in the case of a well nourished frog which has been kept warm, Korybutt, Daskiewicz, and subsequently Stassano and Hass, have seen both the cells of Ehrlich and the clasmatocytes increase. According to Unger, the suppression of the lacteal secretion determines the in- crease of these elements in the breast. On the other hand, West- phal has found numbers of them in the cachectic. As Rosenheim has remarked, their multiplication is quite independent of hypernutrition, and Friedlander, Gleumann, and Ballowitz have quite rightly found but little to justify the expression of Mastzelle which has been given them by Ehrlich. They are found in various pathological products, e.g. liponiata, cutaneous tubercles (Westphal, Bergonzini), urticaria pigmentosa (Unna), the peri-cancerous zone (Ballowitz), miliary epidermic vesicles, sarcomata (Ackermann), nodules of glanders, brown in- duration of the lung (Israel), acute neuritis (Rosenheim), foci of cerebral haemorrhage and multiple sclerosis (Neumann), in the skin of general paralytics (Franca and Athias), and in sleeping sick- ness (Athias). Even supposing that in some of these morbid cases there is really a local hypernutrition, it is quite evident that in certain others at least, there is on the contrary, a true diminu- tion of the local nutrition (lipoma, sleeping sickness, general paralysis). In speaking of each leucocyte, we have indicated the proportion in which it is found in the blood : this proportion is usually sufficiently variable to make it difficult to determine the normal and exact limits, of what has been called " leucocytary equilibrium" Besides, haematologists are hardly agreed in fixing the mean quantity of white corpuscles contained in a cubic millimetre of blood. Hayem fixes it at 6,000 ; Ranvier at 8,000 ; Dumont at 7,650. All numbers, therefore, above 7,500 cannot, as has been stated by Leredde and Loeper, be regarded as pathological. BIBLIOGRAPHY. Leuwenhcek. Opera omnia s. arcana natural detecta. Lugcl. Batav., 1722. Delia Tore. Nuove osservazzione microscopiche. Napoli, 1776. Wharton Jones. 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Journ., sept. 1901. Birri. Sulla nature e s. signif. delle granulazioni iodofile e di quelle eosinopile nei leucociti. II Policlinico, 1901, VIII, p. 299. Grunberg. Beitrage zur vergleichenden Morphologie der Leucocyten. Arch. /. Path. u. Phys.u. f. klin. M ed. , CLXIII (Folge 16, Bd III), 2, p. 303. Poijakoff, Zur Frage von der Enstehung, clem Bau u. der Lebensthatigkeit des Blutes. Arch. /. Anat. u. Phys., 1901 : Anat. Abth., 1. Wolff. Ueber die act. Beweglichkeit d. Lymphocyten. Berlin, klin. Woch., 30 dec. 1901. Dominici. Arch. Med. exp. etd' Anat. path. , 1901-1902. Levaditi. Contrib. a 1'etude des Mastzellen, etc. TheseParis, 1902. THE LYMPHATIC VESSELS. HISTORICAL. Aristotle (384-322 B.C.), as is evident from a phrase in the History of Animals, appears to have seen lymphatic vessels ; but it is to Herophilus (300 B.C.) and to Herasistratus (280 B.C.) to whom we ought, according to the Galenic writings, to attribute the discovery of the chyliferous vessels. Herasistratus saw their milky contents ; Herophilus their termination in the mesenteric glands. The former regarded them as arteries, the latter as veins. These observations, which were denied by Galen, were forgotten, and it was only in 1532, that Nicolas Massa apparently discovered some renal lymphatics. Then Fallopius discovered some white vessels which terminated in the peripancreatic glands. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 57 In 1563, Eustachius discovered the thoracic duct in the horse, and described it under the name of vena alba thoracis as follows: " From the trunk of the left subclavian vein stretches a prolongation which is full of aqueous humour and which divides near its origin into two branches, which soon reunite to constitute a single trunk ; the latter passes along the left side of the spinal column, traverses the diaphragm, arrives nearly to the centre of the lumbar region, where it enlarges, and surrounding the aorta becomes lost, presenting a mode of termination which hitherto has not been recognized." Eustachius therefore saw the inferior "enlargement" of the thoracic duct. Should this justify us in attributing to him, together with Winslow (The Anatomical Exposition of the Structure of the Human Body, MDCCLXI), the discovery of the cistern of Pecquet ? The right lymphatic duct was discovered by Stenon. In 1622, Aselli made a new discovery, viz., the existence of chyliferous vessels. Seeing them in the dog, the cat, the lamb, the cow, the pig, and the horse, he noticed that they joined the mesenteric glands, and he imagined that they terminated in the liver. It fell to Pecquet (1649) to demonstrate their confluence at the swollen commencement of the thoracic duct, to which he gave the name of cistern or reservoir of the chyle. But, as Galen had denied the existence of the canals of Herasistratus and Herophilus, so Riolan and Harvey denied the presence of the lacteal veins of Aselli. To definitely prove their existence, the works of Gassendi (1628), Vessling (1634), Folius and Tulpius (1639), Wallee (1641), and Pecquet (1649), were necessary. Vessling and Rudbeck then described the lymphatics of the liver, the pancreas, the lungs, and the pelvis. Rudbeck concluded from his researches that " the serous vessels " exist not only in the mesentery, but throughout the organism, or that they form a special system. Bartholin and Jolyff did not delay matters by confirming this attempt at generaliza- tion, and the serous system of Rudbeck soon became the lympJiatic system. This substitution of purely verbal terms, resulted in Bartholin being regarded as the author who first attempted to systematize the white vessels. As a result of this new and wider conception of the scope of general anatomy, works on the subject then began to increase, and became so numerous that it is impos- sible for us even to mention them all here. After Rudbeck, Bartholin, Swammerdam and Blasius, Ruysch in 1665, studied the valves, and compared their shape to that of the crescent of the moon. Afterwards, Nuck, R. Hale, Meckel, Haller and Cruickshanks dis- covered new lymphatics in regions which had hitherto not been examined. Hunter found white vessels in the intima, and laid great stress on the im- portant part played by the lymphatic system in the process of absorption. Hewson studied the lymphatics in fishes. In mammals he thought that some of the vessels entered the thoracic duct without traversing the glands. Mascagni, the author of an admirable ichnograph, demonstrated the incorrectness of this idea. With Haller and Cruickshanks, he rejected, in opposition to Stenon, Wepper, Schmiedel, Bcerhave, Bartholin, and Meckel, the view that there is any peripheral communication between the lymphatic and blood systems. According to him, communications with the white vessels take place in the connective tissue, for it is in their meshes that they originate. It so happened that Mascagni was singularly fortunate, for his views were adopted and generalized by Bichat, who admitted the presence of lymphatic openings, not only in the connective tissue, and in serous surfaces, but also in membranous coverings (pores of Haase). 58 THE LYMPHATICS This splendid anatomist remarked that "the lymphatic system essentially enters into the formation of the serous membranes".; he must regard the serous membranes " as large reservoirs intermediate between the exhalent and absorbent, where the lymph in going from one, remains some time before pass- ing into the other, and where it doubtless undergoes various preparations." Some years later, Lippi (1822) and Lauth (1824) discovered the existence of peripheral lymphatico-venous communications ; further, Lauth established the fact that each lymphatic had its origin in a network. Ever since 1832, important works in comparative anatomy by Muller, Panizza and Fohmann have appeared. Jean Muller discovered the posterior lymphatic heart of the frog. Panizza discovered the lymphatic hearts of the ringed adder and the frog. He considered them analogous to the supraval- vular enlargements of the lymphatic trunks of mammals. These organs have been described in some birds by Panizza, Fohmann, and subsequently by Stannius and Gadow. They think these hearts communicate with the veins. Fohmann, who, in opposition to Panizza, regarded the lymphatic hearts as rudimentary glands, admitted with Tiedmann and Louth the existence of lymphatico-venous communications in the interior of the gland. Rusconi described the peri vascular lymphatic sheaths of the frog as a simple " muff " in whose lymph, the blood-vessels are bathed. Later on, Milne-Edwards compared them to the visceral serous membranes of mammals, and Ranvier demonstrated their double endothelium. In 1847, Sappey commenced a long series of researches, which he continued until the publication of his large atlas in 1876. Though the descriptions con- tained therein, which have now become classical, only leave to modern in- vestigators a restricted field of inquiry, it cannot be said that his attempts at general anatomy were so successful. In opposition to Mascagni, he maintains that " a fair number of the constituent parts of the body, viz. the nervous system, the heart and vessels, the mucous surfaces of the bladder, the ureters, the serous surfaces, and the connective tissue elastic and bony, are absolutely and habitually destitute of lymphatic vessels." Further, he also considered that the white vessels take origin from a double network of capil- laries and lacunae which are absolutely closed. Hitherto, problems for dis- cussion had been solved almost entirely by the sole aid of micro- scopic anatomy. Virchow, in 1857, was the first to bring histological methods to bear on the long discussed question of the origin of lym- phatics. An optical error made him describe the connective tissue cell, the plasmatic cell, as star-shaped, hollow, and anastomosing by its prolonga- tions with neighbouring cells. He thought that in the plasmatic system, which is formed by a collection of such cells, circulated the plasma, which gave origin to the lymphatic system. Koelliker, who in 1846, had seen in the tail of the tadpole, lymphatics in process of development, thought that their hollow terminal point was continuous with the prolongations of neigh- bouring connective tissue-cells. He, as did Leydig, also regarded this as a new proof in support of Virchow's theory, which was opposed by Henle, and long since abandoned by Ludwig and Briicke, who were the first to revert to the opinions of Mascagni and Bichat. Recklinghausen, who discovered the lymphatic endothelium, believed also in the existence of plasmatic canals. These " canals of the juice " (Saftkanalchen), have a wall of their own ; they anastomose with each other ; they also form cross- junctions, in the interior of which is found a cell com- posed of a mass of protoplasm. The same scientist demonstrated by a well known experiment, the existence of communications between the lymphatic GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 59 system and the serous cavities, the existence of which had previously been admitted by Bichat. This experiment, repeated and varied by Ludwig, Schweigger-Seidel, Dogiel, Dybkowsky, Wagner, Oedmanson, compelled us to admit the existence of wide orifices, which are always open, and which are situated between the serous and the lymphatic cavities. This conclusicn was invalidated by the histological researches of Ranvier (1873), Hermann and of Tourneaux (1874). Ranvier believed in the existence of a kind of valve with mobile lips, which was capable of being widened by the lymphatic cells. Hermann and Tourneaux, whose views were confirmed by Bizzozero and Salvioli, denied the existence of these orifices, and thought that similar appearances were caused in places where the endothelium was in process of renewal. In 1874, Arnold, again upheld the existence of peripheral communications between the lymphatics, the blood-vessels, and the connective tissue-cells. Tarchanoff (1875) showed that simple appearances might be deceptive. Histological researches soon afforded valuable information regarding the structure of lymphatic channels of all kinds (Recklinghausen, Ranvier, Renaut, etc.), but it was long before they were the means of solving the much vexed question as to the real origin of the white vessels. It was only in 1893, and 1894, that Renaut, Regant and Ranvier definitely settled this question by showing, in accordance with the old opinions held by Belajeff, Dybrowsky, Cohnheim, Robin and Hoggari, that all lymphatics commence in a closed ampulla. Ranvier (1895), studied the development, the involution, and the con- fluence of the lymphatic vessels. He concluded that the lymphatic system resembled a large vascular gland which, originating from the veins, poured into these vessels the product of its secretion, the lymph. Sala, following Budge, traced the formation of the lymphatic hearts and of the thoracic duct in the fowl. The thoracic duct, he regards as a mesenchymatous formation, which is at first absolutely independent of the venous system. Kytmanoff (June 1901), applied Ehrlich's method to the discovery of the nerves of lymphatic vessels, a research which had already been undertaken by Timofejew, Dogiel, Smirnow, Weliki, Quenu and Darier. TECHNICAL METHODS. Though the thoracic duct and chyliferous vessels may be seen without previous preparation, the study of the other lym- phatics necessitates the employment of methods which render them distinct, either by distending their cavities, or shewing their endothelial outline. The methods of descriptive anatomy, were confined to causing dis- tension of the vascular wall, which was usually effected by placing an obstacle in the current of the lymph, together with the injection of some foreign sub- stance. To discover the white vessels of the lung, Willis stopped the flow of lymph, by placing a ligature on the superior extremity of the thoracic duct. With the same object, Ruysch and Cruikshanks ligatured the blood-vessels of the kidnej' in order to see its lymphatics. By this method, the injection was made either directly into an artery, or in a haphazard way into the cellular tissue. The injection of lymphatics by means of the blood-system which was known to Mascagni and Meckel, is less in vogue to-day than interstitial injection, on account of the substances which were used. It would be difficult to mention all the substances which have been tried, since the time of Swammerdann and Ruysch. To show their diversity we need only mention, water, gelatine, wax, oil, Chinese ink, Prussian blue, 60 THE LYMPHATICS carmine in solution or in suspension, mercury, and even microbic cultures. Though Sappey was able to see the deep lymphatics of the kidney by using water, this fluid is not much employed now. Chinese ink, microbes, and coloured gelatine, are especially adapted for histological work, though for macroscopical study mercury, used according to Meckel's method, and per- fected, by Sappey, or the colouring matters used in Gerota's and Boddaert's method are used in preference. SAPPEY'S METHOD. First of all an adult subject, and one as thin as possible, should be selected. If putrefaction is so advanced that the skin is green, and the epidermis raised in large flakes, the injection of the cutaneous lymphatics is favoured, but that of the collecting trunks is hindered, while the study of the submucous and subserous vessels becomes impossible. The apparatus required for the injection of more than 120 centimetres, consists essentially of two tubes. One of these is made of glass arid furnished at either extremity with a metal covering ; at its upper end is a movable eye, by which it is suspended from a smooth pulley, which is attached to a horizontal bar of iron. To its inferior extremity is fixed a flexible tube, which is made of vulcanized caoutchouc, with very thick walls, but with a very small calibre. To the free extremity of the flexible tube is fitted a stopcock and a hollow adjustment with a screw thread ; the glass tube, which has been drawn out in the flame to a fine point for puncturing the tissues, is introduced into the adjustment at its larger end, which has previously been wrapped round with waxed threads. The point of the glass tube must penetrate the superficial layer of the skin, and be worked under a thickness of 2-3 millimetres. The index finger of the right hand then turns the stopcock from right to left. If suc- cessful, the mercury fills the lymphatic network. After half a minute or at the most a minute, the tube is withdrawn, for, if it remains in longer, there is a risk of rupture. It often happens that though the lymphatic plexus is injected, the mercury does not penetrate into the trunks and reach the glands. In this case we must inject the vessel directly, after placing a ligature below the point at which it is proposed to penetrate it. To effect this, Sappey gently depressed the wall and quickly made a puncture into the concavity thus formed. It goes without saying that the injection, should always be made in the direction of the current of the lymph. After the completion of the injection, the connective tissue which surrounds the lymphatic vessels should be left undisturbed, for if a minute dissection is now attempted, there is a great risk that these vessels will be injured, whereas if allowed to dry the connective tissue will become transparent and enable us to see these vessels shining through. During the drying process the parts should be kept in the horizontal position. GEROTA'S METHOD. This author conceived the idea of using absolute black, extractum alkanae, cinnabar and Prussian blue. The extractum alkanae! whose colouring power is somewhat feeble, diffuses and stains the fat. The cinnabar, which is ground in linseed oil and chloroform, is only slightly penetrating. The Prussian blue succeeds the best. Its preparation is for the most part very simple, and is as follows; 2 grammes of Prussian blue kept in tin-foil tubes are taken, to which 3 grammes of pure spirit of tur- pentine are added ; after the whole has been well rubbed down in a china mortar, 15 grammes of sulphuric ether are added, and filtered through a double layer of linen. The solution must be used at once for injection. The injection is made with a syringe, which holds from 10-20 cubic centi- metres, at the end of which is fixed a small adjustment which receives the GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 61 glass needle for puncturing the tissues. To prevent leakage, the larger ex- tremity of the glass needle is wrapped round with a waxed thread. The point is drawn out in the flame. It must not be too fine nor too thick. Though Gerota's method may yield less beautiful preparations than those furnished by mercurial injections, it has a great many advantages from a re- search point of view. Without laying undue stress on the simplicity of the technique, and the cheapness of the preparation, we may observe that it defines lymphatic territories much better than does mercury. This difference between the two methods exists for the following reasons. Mercury often yields extended injections of networks, and always forcibly distends the vessels with very fine walls, of which the latter are composed, but the collecting trunks being more resistant, dilate less. The latter, therefore, are not easily to be distinguished from their plexus of origin. Now Gerota's mixture, which is always injected under low pressure, usually gives a limited injection of the plexus, and leaves to the collecting trunks their preponder- ance in volume ; the result is that the latter are always well seen, and the limits of their boundaries are clearly marked. The possibility of injecting different systems of collecting trunks with different colouring materials, almost enables us to reduce to a system the mapping out of the different territories. Another advantage this method possesses is, that it enables us to study histology. The fact is that microscopical anatomy utilizes methods, not only capable of shewing endothelium, but also methods whereby the vascular cavity is distended by coloured substances, or substances easily recognizable by their histo-chemical reactions. This result is obtained by injection, physiological absorption, or imbibition. The injection may be made either into the dead or the living subject. Coloured substances, injected into the cadaver, are used for the study of blood-vessels. They should have the following qualities: they should be of easy penetration, homogeneous, transparent, and indiffusible. The more satisfactory are carmine substances and the soluble Prussian blues recom- mended by Ranvier. As Prussian blue does not diffuse in aqueous solution, the employment of gelatine, which by its rapid solidification always com- plicates the operation, can be avoided. Other vehicles, such as collodion, albumin, and glycerine yield indifferent or bad results. Though it has been known for some time that the lymphatic vessels possess an absorbing power, it is only in recent years that a procedure known as vital injection, which is based on this fact, has been methodically practised. Whereas Boddaert injects fluorescine, and D'Abundo and Guillain, Chinese ink, Albarran and subsequently Homen and Laitinen inoculate microbes. Though it is well known that certain microbes under conditions as yet imperfectly understood, exercise a remarkable selective power in follow- ing their lymph channels, and thus yield marvellous injections, we cannot disguise from ourselves the fact that such cases are somewhat rare, and their explanation baffles us completely. It is difficult to make certain of obtaining a pure lymphatic injection, and to diminish the vitality and the natural mobility of microbes which, as Guillain has justly observed, can create lesions by themselves or by the toxins to which they give rise, or which may invade the circulatory system. There is another method, based on the physiological absorption of fats by the intestinal lymphatics, which enables us to trace the latter in sections previously treated with osmic acid. 62 THE LYMPHATICS Altmann observed that when any tissue whatsoever imbibes fat, the lympha- tics especially become impregnated with it. To bring into view the lymphatic network, he stains the fatty part of the body black with osmium, and destroys the other parts of the organism by corrosion. He immerses the fresh tissue in a mixture of oil and absolute alcohol, and keeps it in this liquid for five days ; the parts are then washed for three or four hours in distilled water ; this removes the superficial fat, and precipitates that which has penetrated into the lymphatic channels by imbibition ; it is then placed for twenty-four hours in a solution of osmic acid (1 in 100), then submitted to slow corro- sion in bleaching liquid diluted with three times its volume of water. We may actually dispense, as we have done, with the corrosion, and rapidly dehy- drate with absolute alcohol and xylol. By this method, the contents of the vessels alone are coloured black, and stand out clearly on the red-brown back - ground of the preparation. There are several methods used for demonstrating endothelium, but they all reduce themselves to impregjwtion, obtained by a metallic salt, or an anilin colour, such as methylene blue. The silver salts are more used than the salts of gold (Hoggan's method with chloride of gold). Of all the silver salts which have been suggested, viz. picrate, acetate, lactate, (Alferow), nitrate (Recklinghausen), the latter, which is the oldest, is most widely used. Aqueous solutions varying from 1 in 300 to 1 in 1,000 are sometimes used ; sometimes gelatin (Malassez or picric or osmic acid (Renaut) is added. The rectified methylene blue of Ehrlich (Griibler) and of Merck has yielded in the hands of Dogiel and Mayer exceedingly beautiful endothelial im- pregnations. THE ARRANGEMENT AND GENERAL CHARACTERISTICS OF LYMPHATIC VESSELS Originating in the meshes of the connective tissue, the white vessels, that is to say, the lymph passages, which are provided ivith a wall of their oivn, anastomose and form rich peripheral plexuses (the original capillary networks of Lauth, Fohmann, and Panizza). They then decrease in number and reach the glands, in which they again break up into capillaries. After traversing the glands, they pass into the large collecting trunks, viz. the thoracic duct and the right lymphatic duct, by means of which the lymph is conducted into the subclavian veins. Thus in each gland, a true portal lymphatic system exists, and, regarded as a whole, this vast system of branching lym- phatics constitutes a cone-shaped figure whose central apex rests on the venous system. CAPACITY. At their commencement, i.e. at the base of the cone, the lymphatics have a capacity equal to, and greater than, that of the veins. This diminishes the nearer we approach the thoracic duct, the calibre of which is much smaller than that of the vena-cava. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 63 In distinction to the veins, the lymphatics diminish in number without proportionately increasing in calibre. COLOUR. If observed intact in the cadaver, or better still in the living animal, the milky whiteness of the contained lymph can be seen through their fine fragile walls ; the name, lacteal veins, given by Aselli, exactly expresses this appearance. FORM. The lymphatics are sometimes cylindrical, sometimes moniliform, and again, may resemble sacs or crevices. The varia- tions in their structure, and the different texture of tissues traversed, explains this polymorphism. It is only when they possess valves that they present that series of alternate swellings and constrictions to which they owe their characteristic resemblance to chaplets. In their course through the viscera, they are cylindrical. To this rule, which was enunciated by Sappey, there are numerous exceptions. In reality, their form varies according to whether they are isolated in a closely set, dense, connective tissue, or whether they are numerous and situated close together, in a lax connective tissue. If constricted by fascial aponeuroses, such as those in the centre of the diaphragm for example, they are reduced to mere crevices, but in the meshes of a lax connective tissue they dilate to their maximum capacity, anastomose, and tend to run together. Sometimes they are sinuous or sacciform ; thus by their irregularity, they form typical plexuses. VALVES. These do not exist throughout the whole extent of the lymphatic vessels ; they are absent at their com- mencement, and in the capillaries, and are rare in the large collecting trunks (thoracic duct). Sappey has counted, from 60 to 80 in the vessels extending from the fingers to the axillary glands, and from 80 to 100 in the lower limb. At first the valves are only a few millimetres apart from each other, but in the thoracic duct they are separated, by intervals FIG. 10. Valves of the mesenteric chyliferous vessels of the new born cat (picro-osmic mixture, Verick oc. 2 obj. o). Xotice the fineness of some of the anastomotic branches. varying from 6 to 10 centimetres, 64 THE LYMPHATICS and sometimes more. They are arranged in pairs, and resemble the aortic semi-lunar valves, but do not always present at their free bor- der a nodule comparable to the corpora Aurantii. The position of these valves is variable, since even in the same vessel, at one time we see their face, at another, their profile ; and sometimes again we may see them occupying intermediate positions (Ranvier). Some- what resembling a crescent, their free border is turned towards the heart ; their adherent convex edge corresponds to the constriction in the vascular wall. Immediately above this, their vessel wall dilates. ANASTOMOSES. The anastomoses take place by convergence, or by longitudinal communication (Sappey). Frequently, the anasto- motic branches are much finer than the trunks which they unite. SITUATION, DIRECTION. The lymphatics are almost exclusively situated in structures of the connective tissue-type, for, with the exception of the perivascular sheaths of the nervous system, whose functions are under discussion, they never encroach upon the epithelial structures or their derivatives (Renaut). According to their situation, that is, above or below the fascia, on the surface of, or within the viscera, the white vessels are termed either superficial or deep. As a rule, there is a communication between the superficial and deep visceral lymphatics ; Mascagni thought that the same held good for the lymphatics of the limbs ; Sappey, on the contrary, upheld the absolute independence of the epi-and subfascial plexuses. According to Poirier. it can only be a question of relative independence, for such communications are fairly common, especi- ally in the articular regions. Rarely sinuous, the lymphatics are almost always grouped to- gether in the neighbourhood of blood-vessels, which they accompany in almost a straight line. Poirier observed that lymphatic vessels, which p ursue a straight course in the different segments of the limbs become sinuous in the articular regions ; similarly, in the case of the visceral lymphatics, the white vessels may be seen to describe many curves, varying with the displacements and changes in volume of the organ ; thus they become flexuous at the sides of the uterus and in the neck (Poirier), and under the frae- num of the glans (Marchand), they become knotty, etc., etc. Beaunis and Bouchard reject the opinion that the muco- cutaneous lymphatic networks lie above the blood-vessels ; they state that the lymphatic vessels are always and everywhere more deeply situated than the arteries and veins. Ranvier makes GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 65 the same statement, and remarks, that it constitutes a law the physiological significance of which we can understand, seeing that the lymphatics receive material which the blood capillaries have been unwilling or unable to take. Poirier says that though this is true for the networks of origin, it does not hold good for the largest vessels. There, on the contrary, lymphatic vessels may be seen superposed on the larger veins, which they accompany for choice ; in the popliteal space, in the inguinal region, in the iliac fossa, in the axilla, and in the neck, he affirms that the large lymphatic vessels and the glands which they unite in a chain, are placed immediately over the large veins of these regions ; it is only rarely that we see some of the trunks pass behind the veins. We know of hardly an exception to this law established by our master. Surgeons, who frequently have to dissect out diseased lymphatic chains, will con- firm the accuracy of this statement. Such an arrangement is for- tunate, as it makes the dissection easier than it otherwise would be, LYMPHATIC TERRITORIES. The networks of origin, of a given organ, or a given region, often give rise to collecting-trunks, which leave the network at different points, thus constituting several distinct pedicles. Granting the continuity of these trunks with the networks of origin, it would seem at first sight, that an injection made at any point into the latter would fill the network, and then penetrate into the collecting trunks ; and as a matter of fact, in certain organs where the network presents a particular kind of development, and where certain conditions pre- vail, which favour the passage of the mass, this total injection can be obtained ; but it is no less true, that normally, the puncture of a given point of the network injects by preference certain col- lecting-trunks-. We are led to believe that each group of pedicles more especially drains a definite portion of the organ punctured. It is therefore reasonable to assume that in this network, notwithstanding its continuity, there are really several territories, each of which corresponds to a given group of collecting- trunks. It is certain, however, and we cannot repeat it too often, that the independence of these territories is altogether relative, since we can, by a single puncture, and under favourable cir- cumstances, inject all the collecting- trunks ; similarly their limits are somewhat ill-defined. We can, however, at least in certain organs, define their respective limits with sufficient accuracy. We can gauge their extent and thus determine the principal lymphatic channel of a given organ. 66 THE LYMPHATICS Now this knowledge is of considerable practical importance, for neoplastic formations to some extent exaggerate this arrangement. UNEQUAL DISTRIBUTION. The lymphatics are unequally dis- tributed throughout the organism ; and we are almost entirely ignorant of the reason of this apparently capricious distribution. Sappey was astonished to find that the large intestine possessed more white vessels than the small intestine. This fact well shows that the richness in lymphatics of a given organ is not directly propor- tionate to its absorbent functions ; for the bladder, whose healthy mucous coat is impermeable, possesses lymphatics. The number of lymphatics, moreover, apparently bears no constant relation to the elaboration of products, secreted and excreted by the glands, for they are numerous in the mamma and liver, but more scanty in the kidney, pancreas, and thyroid body ; on the other hand, they are found in abundance in the centre of the diaphragm, It seems as though the texture of the surrounding connective tissue influences their number as well as their shape. If the connective tissue is lax, their habitual tendency to run together renders them sinuous or sacciform. They are rarely very large. If the connective tissue is sufficiently dense to resist their dilation and fusion, they become numerous but smaller in size. Thus, Regaud observes that, in the same organ in different species, the lymphatic radicles increase or diminish in pro- portion as the meshes of the connective tissue are dense or lax; in other words, as the drainage of the lymph is difficult or easy. Now do lymphatics exist in all parts of the organism ? Sappey, as we know, denied their existence in the connective tissues, in bone, in the visceral and articular serous membranes, in the arterial walls, in the utero-vesical mucous membranes, and in the nervous system. Though it has been satisfactorily proved that the connective tissue is almost the exclusive seat of the white vessels, their presence in ten- dons and aponeuroses, which was demonstrated by Ludwig and Schwe- igger-Seidel is also clearly proved. Budge, following Cruikshanks, Brugmanns, and Bonamy, has found lymphatics in bone. Tillmanns has described the lymphatics of the articular serous membranes : and we cannot, after the labours of Recklinghausen and Ranvier, deny their existence in the visceral and serous membranes. The researches of Hoggan, d'Albarran, Pasteau, and Gerota demon- strate the existence of vesical lymphatics ; but in spite of the assertions of Hunter, Cruikshanks, Mascagni, Lauth, and Breschet, GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 67 the existence of arterial lymphatics, however probable, is still a moot point. As regards the nervous system, the question is far from being definitely solved. In fact, ordinary white vessels, perivascular sheaths, neuroglia spaces, and even serous clefts, have been described as lymph-channels. Mascagni, Fohmann, Arnold, and Breschet figured lymphatics which they had injected on the sur- face of the brain. Sappey thought this was a matter of injections having been made into the veins or into the cellular tissue, and this opinion has been generally accepted. Notwithstanding this, Poirier maintains that he has seen indisputable lymphatic vessels on the ex- ternal surface of the brain in the arachnoid, and in the dura mater. As regards the perivascular spaces of Robin and His, though their existence may be undeniable, their function has been much discussed. Their lymphatic nature, which was at first almost universally ad- mitted, is now contested. Renaut does not admit the existence of the endothelium formerly described by His and Eberth ; in his opinion these spaces are merely emanations from the amorphous part of the membrana propria which has been compressed by the blood-vessels. Though the spaces studied by Obersteiner, Friedmann, Paladino, Klebs, Rossbach, Schrwald, Kadyi, d'Abundo and Guillain physio- logically appear to have the significance of lymphatic passages, their morphology does not permit of our grouping them with ordi- nary white blood-vessels. The same remark holds good for the canal of the ependyma, and for the serous cavities. Later on, how- ever, we shall have occasion to study the morphological affinities of the serous membranes and the lymphatics. STRUCTURE. According to their structure, lymphatic vessels be- long, some to the type of capillaries, others to that of the collecting -trunks. In the capillaries, the lymph trickles rather than circu- lates, but even in the smallest trunks, the circu- lation is very active. If Prussian blue is injected, it quickly disappears (Ran- vier). The capillaries which F IG . 11. Lymphatic trunk of the subserous layer of the stomach of man (removed by operation). The lymphatic endothelium is stained with silver nitrate. 68 THE LYMPHATICS have no valves are reduced to an endothelial layer. The endothe- lium of the collecting- trunks, which always possess valves, is surrounded by an elastic and muscular sheath of connective tissue. The development of this musculature is somewhat variable ; thus, certain trunks which run in the subcutaneous fibrocellular layer (panniculus acliposus) have no muscle (the lymphatic venules of Renaut) ; again, the thoracic duct of man, which is more muscular than that of the dog, is a lymph propeller of the same type as the smaller trunks for which Renaut reserves this term. Collecting-Trunks. With few exceptions, the lymphatic trunks, whatever their calibre, have the same fundamental structure. For the sake of convenience, we mav re g ar d the wall of the thoracic duct as being formed of three coats, namely an internal or en- dothelial, a middle or muscular, and an external or connective tissue coat. In reality, the internal or endothelial coat is covered by a diffuse connective tissue sheath in which the elastic and muscular elements are irregularly scattered. The endothelial cells which were discovered before those of the blood-vessels, are flat and elongated in the long axis of the ves- sel ; their edges are straight in the subclavian region, and are wavy lower down. This is, says Ranvier, the elementary form of an arrangement which is very well marked in the capillaries. It is nevertheless to be borne in mind that, neither in the thoracic duct, nor in the mesenteric vessels of the rabbit have the endothelial cells the characteristic resemblance to an oak leaf. The endothelium of the thoracic duct in the subclavian region is the same as it is in that of a collateral vein. Renaut has made the same observation in the horse ; this fact appears to him to militate in favour of the venous origin, and centri- fugal development of the thoracic duct. The valves are simple folds of endothelium ; on their internal surface, the cells resemble those which line the vessel wall ; on their external surface, they are polygonal and nearly equal in all their dimensions. In a transverse section, the cells by no means resemble each FIG. J.Lcula. \'2. A transverse section of the thoracic duct of the dog. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 69 other. Some have a moderate amount of homogeneous proto- plasm ; and an oval nucleus with one or two granules of chromatin ; others possess a fine proto- plasmic border from which escape small spherical granules which may be stained by certain colouring acids (eosin, lichtgriin). The nucleus of the latter cells is more elongated, and flatter than those of the former : it nearly always stains diffusely and deeply. It may perhaps be that these cells destroy themselves during the pro- cess of secretion ; in fact, the works of Heidenhain, and Hamburger lead us to think that the lymphatic endothelium, far from being a simple membrane endowed with physical properties, takes an active part in the elaboration of the lymph. Further, Ranvier has demonstrated the his- tological reality of this secretory function of the lymphatic endothelium, and has stated that the cells of the lymphatic vessels of the rabbit's ear, in the normal state, elabor- ate a hyaline substance, quite different from eleidin. This substance swells up as myelin does ; it is cast off from the endothelium in the shape of balls, which when small appear homogeneous ; but which, when larger, exhibit a clear centre and a refracting envelope. They finally fuse with each other and the figure formed resembles a network, with fibrillary arches. Picrocarmin does not stain them, or stains them only pale yellow, though it stains eleidin a vivid red. The connective tissue envelope is composed of lax tissue and of fairly strong longitudinal fibres. In the dog and ass, Renaut has seen the connective tissue cells, which were negatively stained by silver nitrate, shew beneath the endothelium, beautiful Langhans' bodies crossing each other in every direction. This sub-endothelial connective tissue layer is very scanty in the dog and in man. Externally, the connective tissue layer insensibly merges into that of the mediastinal cellulo-adipose tissue. Frequently, the lymphatic wall is penetrated by some fatty cells. This continuity with the surrounding tissue is one of the fundamental character- istics of the structure of white vessels. In the dog, some cells of F FIG. 13. Transverse section of the thoracic duct of the dog. The adventitia is continuous with the sur- rounding celluio - adipose tissue ; in the middle por- tion sections of two blood vessels are seen. 70 THE LYMPHATICS vein i Ehrlich are found, around and even in the wall of the thoracic duct. In the small trunks, the tissue is lax and does not contain longitudinal fibres (Renaut). By the side of the connective tissue fibres, are found very fine elastic fibres which constitute a delicate sub-endothelial network. In this elastic con- nective tissue layer, and especially in its middle portion, are scattered fine mus- iK'SS cular fibres. In the dog, they are, for the greater part, trans- verse ; but some are ...lymphatic obli > lift ?^>>*>---"-- ^J'.V. :\ *. -: *:^.,r~:-^i-^: f --3':-. : . plasm contains three or four gran- ules only. In the connective tissue arches, intheperi- f ollicular layer, and sometimes even, on the border of the follicle, Ehrlich's cells may be seen iso- lated or massed together : there they are small or large, rounded or elongated ; the nucleus, which is usually oval, is at times coloured pale blue, and at others, a violet rose by Unna's blue. I have examined six glands from the pig without being able to find the least trace of haematophagosis. Schumacher, contrary to Rawitz's experience, has proved that the monkey's gland, like that of other mammals, has germinatival centres. Evolutionary Variations. Insenescence. The gland, a highly- developed organ, disappears early, without ever possessing a per- manent structure to any great extent. These incessant variations result from the multiplicity of its functions, especially from its capa- bility of performing the functions of other organs. We know how close are the ties which unite it to the paradigestive lymphoid for- mations, the spleen and even to the bony marrow. The only differences are, that, while the tonsil and spleen consti- tute sites for the origin of the lymphatic vessels, the lymphatic glands, on the contrary, are placed in the course of the latter. The spleen is a gland interposed in the course of the blood stream. Under these circumstances, we can well understand how, in spite of a specialization more apparent than real, numerous vicarious functions are possible which render the study of this organ a very complex one : for instance, after splenectomy, the eosinophiles of the gland increase ; and haematophagosis, usually discreet or insignificant, now assumes larger proportions. Dominici says that GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 101 under these circumstances the gland undergoes splenoid trans- formation. The iron in the gland may increase : with Guillemonat I have found, in such cases 0'06 gr. 0'08 gr. and even O'll gr. of this metal in each 100 parts. Twice, on the contrary, I have only found traces of it. On the other hand, after bleeding and exhaustion it seems to diminish. We shall see, however, that some authors, on the con- trary maintain that under these conditions, glandular haemato- poiesis is more active. In an animal during gestation, it is not unusual to find a consider- able number of nucleated red blood cells (Masslow). Dominici describes the gland of a preg- nant female as a gland which is undergoing myeloid trans- formation. To glands which contain many Neumann's and Ehrlich's cells, eosinophiles, with a single nucleus, and polynuclears, Scott Warthin gives the name of myelolymphatic glands. Insenescence. Atrophy takes place prematurely, seeing that in the adult man, all mitoses may be observed to disappear, and sclerosis makes its appearance ; the latter process invades the whole of the organ in the aged. This sclerosis is peripheral and central. At the periphery, it is the capsule which thickens ; while at the centre, it is the excessive proliferation of the perivascular arches which transforms the medulla into a fibrous block ; but, surrounded in this concentric sclerotic band, there still remains a fine band of cortical substance which is, in its turn, eventually split up and invaded by the sclerosis which makes its appearance round the vessels (vide fig. 32). Demoor does not agree with Orth, His, and Billroth, who maintain that as age advances, the nuclei in the cells of the network eventually disappear completely. Contrary to Frey's experience, he did not observe the fatty degeneration or pigmentary infiltration of the cells of the network. I looked for one or the other of these changes in three or four very old dead subjects, but in vain. In FIG. 32. Mesenteric gland from an old man. 102 THE LYMPHATICS these fibrous glands there are no longer traces of macrocytes (macrophages) in the sinuses. FUNCTIONS. Leucocytocjenesis. Whether glandular cells are fixed leucocytes or autochtonous derivatives of mesodermic elements, at any rate they produce the white corpuscles. In fact, the latter are more numerous in the efferent than in the afferent vessels ; there is a close relation between blood leucocytosis, glandular hypertrophies, and the number of mitoses. Similarly, the experimental removal of certain important glandular groups produces hypoleucocytosis. The glandular cells are therefore clearly lymphogenous, and the gland is a cytogenous gland like the testicle. In this connexion, it is interesting to recall the fact that these two mesodermic organs which are so distinct in vertebrates, are blended in certain invertebrates, viz. the lympho-sexual glands of the Bryozoae, and of some of the Polychetae (Cuenot). The gland specially produces microcytes (lymphocytes), and very probably, macrocytes (large mononuclears) also. The microcytes, numerous in the gland and in the efferent channels, increase in pathological or experimental (splenectomy) glandular hypertro- phies. On the other hand, they diminish after extensive glandular ablations (Rokitzki, Tchigaieff, Ehrlich and Reinbach), and after ligature of the thoracic duct (Koroboff). There, eosinophiles are again formed and perhaps also, sometimes, cells with neutrophile granules. The eosinophiles, which are often numerous, rarely present mitoses : Jolly has seen one in the rabbit ; I have seen one in the hedgehog : it is the eosinophiles with a single round nucleus which are more frequently observed in the gland or in the lymphoid portion of the thymus; Labbe notes the existence of simi- lar cells in the guinea-pig, and I have found them in the rabbit, pig and hedgehog. Further, there are some eosinophiles with few granules, whose nucleus, in its shape, staining properties, and arrangement of its chromatin, resembles at times microcytes, and at others, ordinary macrocytes. It would seem as though we were witnessing the first appearance of granules and their progressive development in a cell which was at first destitute of them. We should also note the presence of the blood eosinophile which accompanies certain glandular hyper- trophies (lymphadenoma, splenectomy). It is therefore almost certain that, following the opinion of Hoyer, Schaffer, and more recently of Labbe, there is sometimes, if not always, a production of eosinophiles in the lymphoid tissues (gland and thymus). In the normal frog^ GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 103 eosinophiles are produced in the spleen. It has long been known that the gland encloses multinucleated cells, and cells with a polymorphous nucleus; but the polymorphism of the nuclsus does not necessarily imply the presence of neutrophile granules. Quite recently, Dominici has seen cells with neutrophile granules develop in lymphoid tissue. This is the natural and almost necessary consequence of the presence in the tissue of basophile macrocytes analogous to myelocytes. Haematopoiesis. Now to complete its resemblance to the bony marrow and the embryonic spleen, we may inquire if the gland is, or at any rate can under any circumstances become, a centre of haematopoiesis ? The possibility of its acting as a substitute in this way seems demonstrated by a very suggestive observation of Rindfleisch. This pathological anatomist found Neumann's cells in the hyper- trophied glands of a rachitic infant, in whom the bony marrow was absent. Saxer attributes this function to the embryonic gland, and Retterer regards it as a fundamental property of adult lymphoid tissue. According to this histologist, the glandular cells elaborate red b'ood cells, either by means of their nucleus, or of their protoplasm : the "haemoglobic degeneration" of the nucleus gives rise to red discoid blood globules, while that of the protoplasm, which is less common, produces red nucleated corpuscles. There are certain glandular cells, the nucleus of which when in a state of degeneration, stains with cosine or orange, and which in shape very closely resembles red corpuscles. Is this sufficient to prove that these elements are red corpuscles in process of formation ? We may at least have our doubts on this point. The lymphoid tissue and the sinus may, however, contain red blood cells, which are sometimes nucleated. As regards the pathological con- dition, when there are congestions, or visceral haemorrhages, when the blood carries away Neumann's cells, this state- ment furnishes no decisive argument in favour of glandular haematopoiesis. Under these circumstances, it is, in fact, impossible to prove that the red blood cells found in the gland have originated there, and have not arrived there through diapedesis (Schumacher), or through a vascular rupture (Saltikow). On the other hand, we cannot assume a similar origin for the cells of Neumann which, while absent in the normal blood of adults, are sometimes present in the cortical layer and in the cavernous passages 104 THE LYMPHATICS of the gland. I observed this fact in the grey rat and in the pig : in the rat, we have to deal with giant nucleated red blood cells almost entirely, whose protoplasm is unequally rich in haemoglobin. Some possess a nucleus, in which a reticulum and chromatin nucleoli can be distinguished ; others have a smaller nucleus deeply and diffusely stained ; finally there are some in which the nucleus is very pale, poor in chromatin, and seems to be in process of disappearing. In the pig, the nucleated red blood cells, which are usually small, are transformed into ordinary red blood corpuscles by nuclear excretion. Glandular haematopoiesis, though it sometimes undoubtedly takes place, seems very inconstant, or atany rate very intermittent : histolo- gical examination by no means always demonstrates the constant presence of Neumann's cells in glandular tissue : moreover, chemical analysis agrees with histology in proving this inconstancy. In glands taken from the slaughter house, Schmidt found no haemoglobin. In six out of fourteen examinations, we, agreeing with Guillemonat, found only inappreciable traces of iron (three times an infinitesimal amount, and three times larger traces). 1 Haematolysis and Phagocytosis. In the pathological state owing to the presence of its macrocytes (rnacrophages of Metch- nikoff), the gland may become an active centre of haematophagasis and consequently of haematolysis. In intoxications caused by phosphorus and arsenic, and in poisoning by toluilin-diamin, Hover observed numerous examples of glandular haematophagasis, and though Retterer denies this function, Gabbi, Schumacher, and Thome regard it as a constant function of the healthy gland. Scott Warthin localizes this function in certain glands, or rather in certain haemolymphatic or splenoidal glands, which have been studied by Leydig, Gibbes, Robertson, Clarkson, Sisto and Morandi, Morandi and Piato. It is quite clear that if haematophagasis were present to any great extent in all normal glands the latter would be red and would always contain iron in fairly large proportion ; we know, however, that such is not the case. Moreover, we do not always see the histological signs of an 1 The estimations were carried out by Lapicque's method. The animals (pig, dog, rabbit, rat) were killed by bleeding, and the glands washed in dis- tilled water. We have thus as far as possible avoided the cause of error due to the presence of blood; this cause of error is more easily elim- inated in the case of the gland than in that of the spleen. GENERAL ANATOMY OF THE LYMPHATIC SYSTEM 105 extensive glandular haemolysis in the normal state. This process, which is often absent or insignificant, has not appeared to me so marked as it is in the mesenteric glands of the rabbit after splenectomy, or after the injection of pilocarpine. Even after splenectomy, it is inconstant or transitory. At various times after this operation I have examined the mesenteric glands of eight rabbits, without ever observing (contrary to the experience of Lockart Gibson and Moses Griinberg), the slightest redness or the least macroscopic hypertrophy. The increase in the amount of iron is also inconstant. Though, on three occasions, 0*06 gr., 0'08 gr., and O'll in each 1000 parts were found, on two occasions, there were only traces. We can understand how the same organ exercises these two antagonistic functions of haematolysis and haematopoiesis simul- taneously or intermittently, seeing that the former furnishes the materials for the latter process. Owing to its slow circulation and to its innumerable phagocytes, the gland is also a place where inert or living particles brought to it by the afferents are arrested. We are acquainted with the carbon infiltration of bronchial glands, and the yellowish green pigmentation of the mesenteric glands of the rabbit. Schmorl found that glands draining a pigmented or tattoed cutaneous area were blackish in colour. The question of the presence of bacteria in the normal gland opens a wider field for discussion. Wissokowitch, Xeisser and Labbe found the glands sterile ; Loomis, Pizzini, and Kossel were able by inoculation to demonstrate the septic properties of some of them. Perey found in them both saprophytic and pathogenic agents ; while Desourbry and Porcher, and Josue found microbes in the thoracic duct. In the closed follicles of the appendix of the rabbit I have found, as Denys has, bacilli, even though the mucus membrane was his- tologically intact, and I have found the same thing in the pig's gland. The normal gland may then contain germs, and it is possible that these germs may not be entirely disconnected with the produc- tion of the numerous soluble ferments which are now being studied. Amorphous Secretions. Rossbach observed the presence of an amylase in the tonsil. Foa and Pellacani produced coagulation of the blood by the intravascular injection of glandular extracts ; the lymphatic glands apparently contain thrombase. The difference in the amount of fat contained in the afferent and efferent chyle H 106 THE LYMPHATICS had long been observed ; quite recently, Poulain found in the gland the lipase, the existence of which was known in the thymus. The recent researches of Arthus and Doyon however, take away all interest in this statement. Delezenne has discovered in the mesenteric glands of the dog, the pig, and the rabbit an " enterokynase " a ferment which aids the trypsin, and which exists also in Fever's patches. Metchnikoff notes the presence of a " fixer " in the mesenteric glands. Taressewitch states that, in a glandular extract, the red blood corpuscles are nearly always dissolved : this is not the case in the marrow of bone ; he attributes this action to the presence of a ferment (?) the macrocytase. Whatever the truth may be as to the real nature of this macrocytase, the gland contains ferments, the exact origin of which we have still to learn. On the other hand, the gland is an important centre for cytolysis : its cells degenerate, become vacuolated, and shed their nuclei ; the eosinophiles, the cells of Ehrlich, there heap up their granules : regarded from these two points of view, it behaves like a secreting gland, that is to say, like an organ which, by a partial or total destruction of some of its elements, sets free into the circulation a product which is useful for the needs of the organism. According to Asher, the products of katabolism provoke the glandular functions, and the result of this is the transformation of the waste products of cellular life. 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Arch, per le Scienze mediche, vol. XXV. Feb., 1902. SECOND PART Special Study of the Lymphatics of the Body BY P. POIRIER AND B. CUNfiO WE will study in succession : 1. The lymphatics of the lower limb (chap. i.). 2. pelvis and abdomen (chap. ii.). 3. ,, ,, ,, thorax (chap. iii.). * ,, upper limb (chap. iv.). 5- ,, ,, head and neck (chap. v.). In each chapter we will first consider the different glandular groups and the arrangement of their afferent and efferent vessels. We will then return to the arrangement of the lymphatics of the organs and the tributary regions of these glands. We will terminate this portion of the book by studying the two large collecting trunks into which almost all the lymphatic vessels of the human subject eventually pour their contents, viz. the thoracic duct and right lymphatic duct (chap. vi.). CHAPTER I THE LYMPHATICS OF THE LOWER LIMB THE lymphatic vessels of the lower limb are arranged in two groups ; one (the superficial lymphatics) run in the subcutaneous cellular tissue, the other (the deep lymphatics) run under the aponeurosis. All converge towards the inguinal region, where they terminate in the superficial or deep inguinal glands. These inguinal glands thus form the common meeting place of almost all the lymphatics of the lower limb. However, some of these vessels have already traversed certain glands of much less importance, it is true, namely the anterior tibial and the popliteal glands. We will first of all describe the arrangement of these different glandular groups. We will 112 SPECIAL STUDY OF THE LYMPHATICS Anterior tibiil gland then give a description of all the lymphatic vessels of the lower limb. 1. GLANDULAR GROUPS OF THE LOWER LIMB WE will study in turn the anterior tibial, the popliteal, and the inguinal glands. Anterior Tibial Gland. The anterior tibial gland, described and figured for the first time by Mascagni (loc. cit. p. 39, and plate vi. fig. 2), is always very small. It is placed in the course of the anterior tibial vessels at their upper part ; it rests on the interosseous ligament. It is generally ad- mitted that the anterior tibial gland receives an anterior tibial trunk, as an afferent, and gives off an efferent which ends in the popliteal glands. It would be perhaps more correct to say it is a simple nodule which in- terrupts the course of one of the anterior tibial trunks which end in the popliteal glands. VARIETIES. The existence of the anterior tibial gland is far from being constant. Cruikshank and Hunter make no mention of it. Bourgery and Leaf regard it as very inconstant. On the other hand it may be double (Mascagni, Hewson, FIG. 33. Anterior tibial lymphatics and anterior tibial Meckel), and descend as far gland (after Bonamy, Broca and Beau). ag the middle of the limb (Hewson). The inconstancy of this gland, its small size, its variations in number and situation, clearly prove that from the phylogenic point of view it is of Anterior libi'il trunk Anterior pcronenl'artery Internal plantar tributary Dorsalis pedis tributary External plantar tributary THE LYMPHATICS OF THE LOWER LIMB 113 recent formation. In fact, it is not so much a gland properly so called as a simple interrupting glandular nodule (Schaltdruse), which does not present the morphological fixity of the regional glands (vide, p. 86). But with our present knowledge of the general evolution of the glandular apparatus in the higher vertebrates, \ve are bound to admit that this nodule is in process of being raised to the dignity of a gland properly so called. In other words, its increase in size, and its division into two, should be regarded as progressive anomalies, its reduced size and its disappearance, as a return to the primitive state. Popliteal Glands. All the popliteal glands are sub-aponeurotic. As they are nearly always very small, and buried in the fatty tissue which fills the popliteal space, they are difficult to find unless their afferent vessels have been previously injected. They may be divided into three groups, which extend from the under surface of the aponeurosis to the posterior ligament of the knee joint. (a) A primary gland is generally found beneath the aponeurosis, external to the terminal portion of the external saphenous vein, and internal to the external popliteal nerve. This is the external saphenous gland. Sometimes this gland is placed at a higher level, on an anast omo tic branch be- tween the external and internal sa- phenous vein. (b) A se- cond group (the middle glands), which is of much more importance, comprises 2 to 4 glands more deeply situated on the lateral parts of the popliteal ves- sels ; these Internal popliteal nerve. Popliteal vein. Popliteal artery. External popliteal nerve. Supra condyloid gland. Inter tondyloid gland. Juxla-Saphenous gland. FIG. 34. Glands of the popliteal space. 11 114 SPECIAL STUDY OF THE LYMPHATICS glands are situated some external to, and some internal to the ves- sels, and often form two distinct masses ; one, the inferior, is placed at the level of the condyles, in the intercondyloid space (intercondy- loid glands, Leaf) ; the other, the superior, is situated above these bony prominences (supracondyloid glands, Leaf) (vide fig. 40). (c) Finally, a gland may be found attached to the posterior ligament of the knee joint, in front of the artery (juxta-articular gland). AFFERENT VESSELS. In each of these glandular groups, distinct afferents terminate. The external saphenous gland receives the vessels which accompany the external saphenous vein. These vessels come from the posterior third of the external border of the foot, from the outer part of the heel, and from the posterior surface of the limb. The middle glands receive (1) the afferent lymphatics of the anterior tibial gland ; (2) the deep lymphatics which accompany the posterior tibial and peroneal vessels. The juxta-articular gland receives the lymphatics which come from the knee joint and accompany the articular arteries (Bardeleben, Naeckel and Frohse). EFFERENT VESSELS. The efferent vessels of the popliteal glands may be divided into two groups. (a) A deep group which comprises 2 to 4 trunks which follow the popliteal vein, and then the femoral vein, and end in the deep inguinal glands. (b) A superficial group comprising 1 to 2 trunks which follow the anastomotic branches between the external and internal saphenous veins, and which all unite with the satellite trunks of this vessel and terminate in the infero-internal group of inguinal glands. This latter route is less important than the former and may be absent. Bardeleben, Naeckel and Frohse admit the further possibility of a third efferent route, winch if present accompanies the great sciatic nerve. VARIETIES. The popliteal glands present numerous variations. We have taken as the type of our description the arrangement which has appeared to us to be the most frequent. Of the three groups which we have described, the most constant is the middle group. The external saphenous gland and the juxta-articular gland are not infrequently absent. A gland is sometimes found abnormally placed on the fibrous arch of the soleus muscle (tibio- popliteal, Bougery, loc. cit. vol. iv., plate 82). Inguinal Glands. The inguinal glands are much more numer- ous than the preceding, and constitute one of the more important glandular centres of the body. They are distinguished as super- ficial and deep. THE LYMPHATICS OF THE LOWER LIMB 115 SUPERFICIAL INGUINAL GLANDS. The superficial inguinal glands occupy the whole of Scarpa's triangle. The space they occupy is limited above, by Poupart's ligament, externally by a vertical line passing through the anterior inferior iliac spine, internally, by a second vertical line drawn through the pubic spine, below, by a horizontal line placed six or seven centimetres below Poupart's ligament. They are placed in the deep layer of the superficial fascia, and are in relation with the following subcutaneous organs in this region : the subcutaneous abdominal arteries, viz. the super- ficial circumflex iliac, superficial external pudic ; the corresponding veins, the terminal portion of the internal saphenous vein, and the crural branch of the geni to-crural nerve. The number of these glands is somewhat variable. Moreover, to succeed in estimating them accurately it is essential that their afferent vessels should be injected ; for injections, and more particu- larly coloured injections, enable us to discover small glands Avhich in a simple dissection would certainly escape notice. It may then be seen that they vary in number from 10 to 20 ; their size is no less variable than their number. As a result of the constant infections to which they are exposed, they are not infrequently found hypertrophied. On account of their number, and the large space occupied by these glands, the majority of anatomists divide them into several groups. We must remark, however, that all these divisions are absolutely artificial. On the one hand, all of them as a matter of fact are scattered about \vithoutapparent order, so that it is impos- sible to group them into distinct masses, characterized by a constant topography. On the other hand, though each of the different regions whose lymphatics are tributaries of the inguinal glands send by preference their vessels to certain of these glands, there is no arrangement sufficiently constant to serve as a basis for a natural classification. We recognize, however, the necessity for dividing the superficial inguinal glands into several groups, though we would again insist on the purely conventional nature of any division. With these reservations, we will adopt the following classification, which is almost identical with that proposed by Quenu and since accepted by Gerota, Bardeleben, Naeckel, and Frohse, etc. A horizontal line passing through the saphenous opening, divides the superficial inguinal groups into two groups : a superior and an inferior. A vertical line passing through the saphenous opening, divides each of these groups into two secondary groups, one external 116 SPECIAL STUDY OF THE LYMPHATICS >upert ' Superior intermit (/land. Inferior intern-.il y'-ini'J. and the other internal. Finally, there is often a central group, formed by 1 to 3 small glands placed in the actual orifice of the internal saphenous opening. According to Leaf, it is not unusual to find one of these glands embedded in the fatty laj^er in the imme- diate vicinity of the saphenous opening, thus constituting a transition between the super- ficial and the deep glands. To sum up - - The superficial inguinal g 1 a n d s m ay be divided into five groups : ( 1 ) supero- ex ternal. (2) supero- internal, (3) infero- internal ( 4) infero-ex ternal. (5) central group (parasphenous glands of Quenu r ) The two superior groups are formed by a series of glands fairly regularly arranged below the crural arch, and having their long axis parallel to it. The arrangement of the lower groups is much more irregular. Though the lowest are usually elongated in the vertical direction, parallel to the axis of the limb, the majority of them are round or oval and irregularly scattered about. There are many other classifications of the superficial inguinal glands. We are aware of the classical division into a superior or horizontal group (in- guinal glands), and an inferior or vertical group (crural glands). The former would receive the genital, anal, abdominal, and gluteal lymphatics : the latter, the lymphatics of the lower limb* Though this classification may suffice from the clinical, it does not do from the anatomical point of view. There are numbers of round glands situated in the centre of this region, and one does not know in which group they should be included. Moreover, we shall shortly see that the termination of the afferent lymphatics is far from being as syste- matic as this classification would seem to indicate. Sappey gives a different classification which we think it advisable to mention here, because it has been adopted by a certain number of authors. He describes a superior group which occupies the inguinal region ; an inferior group, the glands of which Fro. 35. Superficial inguinal glands. The cribriform fascia Vicing removed, exposes the upper part of the femoral vessels. THE LYMPHATICS OF THE LOWER LIMB 117 are placed round the internal saphenous vein ; an internal group, placed within the saphenous opening ; an external group, situated external to the termination of this vessel ; and finally a central group, which has no fixed position or relation. Aberrant Glands. We may frequently come across aberrant superficial inguinal glands, situated external to the region which we have indicated above as being their more usual site. Thus Au spitz has observed the possible presence of little glands below the anterior superior iliac spine (extra-inguinal). Similarly, Lejars lias come across glands placed above the crural arch and beneath the abdominal skin (supra-inguinal). AFFERENT VESSELS. The superficial inguinal glands receive the cutaneous lymphatics of the lower limb, the perineum, the scrotum, the penis, the prepuce of the clitoris, the anus, and the sub-umbilical portion of the abdominal wall. According to Sappey, the lymphatics of the glans penis, and glans clitoridis both throw themselves into the superficial inguinal glands ; but we shall see further on that this termination is exceptional and that these vessels are normally tributaries of the deep inguinal glands (vide pp. 156 and 159). It was formerly an accepted fact that each of the lymphatic territories which we are to describe, corresponds to a definite glandular group ; and it was, and for good reason, still is the custom to teach that, in certain symptomatic adenopathies it is possible, from the form and situation of the infected glands, to diagnose with certainty the position of the lesion. We will not repeat the different classifications which have been proposed, as none of them sufficiently indicate the facts. Recent researches have in fact satisfactorily shewn that the division of the inguinal glands into several groups is only of value for the sake of convenience, and that the lymphatics which come even from the same region, may terminate in different groups ; thus the lymphatics of the lower limb terminate both in the infero-external and in the infero-internal group. Similarly, the lymphatics of the scrotum and the coverings of the penis usually end in the supero-internal group, but they may also end in the glands of the infero-internal group (vide p. 153). The same holds good for the lymphatics of the prepuce of the clitoris, the iabia majora and minora (Bruhns) (vide p. 158). The lymphatics of the perineum terminate in the supero-external and supero-internal groups. The lymphatics of the anus usually pass into the supero-internal, but may terminate in the infero-external glands, or again they may be tributaries to these two groups at the same time ; it is equally possible, though perhaps rather exceptional, to see one or several of them reach the central, or one of the external groups (Quenii, Gerota) (vide pp. 188 and 189). 118 SPECIAL STUDY OF THE LYMPHATICS The cutaneous lymphatics of the umbilicus and of the sub umbilical portion of the abdominal wall end in the supero-internal and supero- external glands (Bruhns, Cuneo and Mareille) (vide pp. 149 and 150). FIG 36. Glands of the inguinal region; afferent and efferent lymphatics (taken from Sappey's atlas). 1,1. The two lowest glands of the inguinal region both remarkable for their size. 2. Infero-external gland. 3,3. Internal inguinal glands to which pass the lymphatics of the scrotum, perineum, the anal region, and the supero-internal part of the integuments of the thigh. 4. Supero-internal inguinal gland ; it receives vessels coming from the urethra, and from the surface of the glans and coverings of the penis. 5,5. Supero-internal and external inguinal glands, into which three or four lymphatics from the sub-umbilical portion of the abdomen terminate. 6,6. Lymphatic vessels from the antero-internal portion of the thigh. 7,7. Vessels from the external portion of the thigh. 8,8. Vessels from the gluteal region. d,9. Vessels from the lumbar region. 10, 10, 10. Vessels from the sub-umbilical portion of the anterior wall of the abdomen. 11,11. Lymphatic vessels of the scrotum. 12. Lymphatic vessels of the prepuce. 13, 13. Lymphatic vessels of the coverings of the penis. 14. Lymphatic trunk which surrounds the corona of the glans. 15. Median trunk which continues the course of the preceding. 16. Umbilicus. The lymphatics of the buttock generally terminate in the supero- external group, but may also end in the infero-external glands. EFFERENT VESSELS. The efferent vessels of the superficial ingui- nal glands end in the deep inguinal, or in the external iliac glands. To THE LYMPHATICS OF THE LOWER LIMB 119 reach these glands they must pass through the femoral sheath : there are numerous orifices through which they pass, which give to the upper part of this sheath its characteristic stippled appearance. The efferents which terminate in the deep inguinal glands are the least numerous. They come especially from the glands of the two lower groups. The efferents which terminate in the pelvis are much more im- portant ; they vary in number from 8 to 12, and are always of considerable calibre. They pass into the pelvic cavity through the crural ring, and accompany the femoral vessels. Some of them pass in front of these vessels, but the majority run along the inner part of the ring, internal to the femoral vein. At this point, some of them may be interrupted by the gland of Cloquet; but the majority end in two glands, viz. the external and internal retro- crural (vide pp. 130 and 131, fig. 41). DEEP INGUINAL GLANDS. The deep inguinal or sub-aponeurotic glands are much less important than the superficial glands. They vary in number from 1 to 3, and are not usually of large size. In order to understand their precise arrangement and relations, their afferent vessels must be injected. It can then be seen that these glands are placed internal to the femoral vein. When there are three of them, the lowest is placed below the point where the external saphenous joins the femoral vein. The supra jacent gland is lodged in the crural canal. Finally, the superior gland occupies the external part of the crural canal, and protrudes through the septum crurale into the pelvic cavity. It is continuous in the pelvis with the internal chain of external iliac glands (vide p. 132). This gland of the crural ring, from the clinical point of view, has a certain amount of interest, for, on account of its situation, it may become inflamed, and may then simulate a strangulated femoral hernia. French authors generally call it the gland of Cloquet while the Germans call it the gland of Rosenmiiller. AFFERENT VESSELS. The deep inguinal glands receive : 1. Some of the afferents from the superficial inguinal glands. 2. The deep lymphatics which accompany the superficial femoral vessels. 3. The deep lymphatics which accompany the deep femoral vessels. 4. The lymphatics from the glands in the male, and the clitoris in the female. EFFERENT VESSELS. The efferent vessels penetrate into the pelvic cavity and almost all terminate in the retro-crural internal gland. 120 SPECIAL STUDY OF THE LYMPHATICS One or two may, however, end in the retro-crural external gland. The most inconstant of these glands is the middle gland. The gland of Cloquet is also not uncommonly absent. Moreover, the total absence of the deep inguinal glands is far from being rare, but this statement cannot be made unless the deep femoral lymphatics have previously been injected. Unless this precaution is taken, these glands, which are lost in the fat, may not be recognized. In our view, certain authors, such as Auspitz, are quite wrong in regarding their absence as the rule. Owing to the small size and inconstancy of the deep inguinal glands, Stahr regards them as simple nodules (Schaltdriise), interposed in the course of the deep lymphatics of the lower limb (Stahr). This way of regarding them, we think incorrect, for it is at variance with the fact that the deep inguinal glands have other afferents than the femoral trunks, seeing that they receive the deep lymphatics from the penis and clitoris (Marcille). They are therefore true regional glands. On the other hand, we must recognize that the number and size of these glands is by no means proportionate to the importance of the deep femoral lymphatics : and it is difficult to understand what error caused Bourgery to estimate these glands as six or eight in number. The gland figured by Bourgerj^ in the course of the internal circumflex vessels (Bourgery, loc. cit. vol. 4, plate 82), and one or two small glands which are sometimes met with in the course of the femoral vessels in the middle part of the thigh may be regarded as aberrant elements of this group. Upon the topography of the inguinal glands vide Mascagni, loc. cit. p. 37 et Tab., iv, viii, x. Sappey, loc. cit. p. G3 et pi. vii, viii et xi. Auspitz, die Bubonen der Leistengegend, Arch f. Dermat, u. Syphilis, 1873, Bd v, p. 443. Zeissl u. Horowitz, IKtener klin. Wochcnschr., 1890, p. 388, et Wiener medicin. Presse, Bd xxxviii, p. 761. Leaf, loc. cit., p. 67. Felizet, Note clinique sur les ganglions cVaboutissement des membres, Bull. Soc. Chir., 1893, p. 521. Quenu, Journal de I Anat. f 1893, 11. 4, p. 523. Bruhns. Ueber die Lymphgefasse der aiisserem mannlichen Genitalien. u. der Zuflusse der Leisteiidriisen, Arch. /. Anat. u. Phys., Anat. Abth., 1900. p. 281. 2. LYMPHATIC VESSELS OF THE LOWER LIMB. As we have seen above, we may divide the lymphatics of the lower limb into superficial lymphatics, which take origin in the integuments, the collecting trunks of which run in the subcutaneous cellular tissue, and into deep lymphatics which arise in the sub-aponeurotic organs, and end in trunks which closely accompany the vessels and nerves. Superficial Lymphatics. The superficial lymphatics emerge at all points from the cutaneous envelope of the limb ; but it is in the foot that the network of origin presents its maximum de- velopment. It is in this situation too, and particularly on the lateral surfaces of the toes and margins of the sole of the foot, that the attempt must be made to inject these vessels. On the other hand, in the rest of the limb, with the exception perhaps, of the prae-patellar region, the network of origin has extremely fine meshes, and its injection offers great difficulties. THE LYMPHATICS OF THE LOWER LIMB 121 The collecting trunks which come from this network may be divided into three groups: (1) the collectors which accompany the internal saphenous vein, which are tributaries of the inguinal glands and which drain almost the entire cutaneous sur- face of the lower limb ; (2) the collecting trunks which accom- pany the external saphenous and which end in the FIG. 37. The superficial lymphatic vessels of the foot (after Sappey), 1.1. Lymphatic network of the external border of the foot. 2,2. Lymphatic network of the toes. 3. Lymphatic network of the skin of the heel. 4, 4, 4, 4. Lymphatic vessels which accompany the external saphenous vein and terminate in the popliteal glands. 5, 5, 5. Lymphatic trunks on the dorsal surface of the foot. 6,6. Lymphatic trunks which run from the external towards the internal surface of the limb. 7, 7, 7, 7. Networks from each of which runs a little trunk, which terminates in one of the neighbouring trunks. popliteal glands ; (3) the collecting trunks of the gluteal region. (1) TlIE COLLECTING TRUNKS WHICH FOLLOW THE COURSE OF THE INTERNAL SAPHENOUS VEIN. These collecting trunks first appear in the toes. From the network which covers them, spring a considerable number of little trunks, some of which run towards the internal surface, and others towards the external surface of each toe, from both the dorsal and plantar aspect. ;; In joining together, the dorsal and palmar trunks constitute on each lateral surface two principal trunks, parallel to the corre- sponding collateral artery, above which they are situated. At the level of the metatarso-phalangeal articulations, these trunks communicate with each other in various ways ; sometimes, the external collaterals of one toe unite with the internal collaterals of a neighbouring toe ; and sometimes, the four trunks from the same 122 SPECIAL STUDY OF THE LYMPHATICS toe unite to form a single trunk which divides a little farther up into two trunks which blend with the trunks which are nearest to them. From these communications a large plexus results, the elongated meshes of which, from before backwards, are spread 14 out under the integuments on the dorsal surface of the foot" (Sappey). In each interdigital space, this dorsal plexus is augmented by the trunks coming from the plantar region. These trunks, three or four for each space, originate at the level of the heads of the metatarsal bones, the} r converge from behind for- wards towards the interdigital spaces, and then bend round to gain the dorsal surface of the foot. From this dorsal network, several col- lecting trunks arise which, with Sappey, we may divide into internal and external. The internal collecting trunks arise from the two inner toes and from the internal third of the dorsal network. Immediately after their origin, they are augmented by the internal plantar trunks which, as they turn round the internal border of the foot, number about twelve to fifteen, but become reduced to four or five after their arrival on the dorsal surface of the foot. The internal collecting 1, 1. Lymphatic network of the internal portion of the sole of the foot. 2, 2. Lymphatic vessels which run from it. 3. Other lymphatic trunks of the dorsal surface of the foot. 4. Large trunk which passes in front of the internal malleolus. 5, 5. Vessels situated in front of and behind this trunk. 6, 6. Vessels coming from the external surface of the limb. 7, 7. General view of lym- phatic vessels situated on the internal surface of the iimb. 8. Vessels bending round the postero-internal part of the knee. 9. Vessels which skirt the front of the articulation ; they differ from the preceding in their sinuosities. 10, 10. Vessels which take origin from the posterior portion of the thigh. 11, 11. Vessels which come from the an tero -external part. 12, 12. Group of trunks which correspond to the ant ero -internal part. 13. Large glands in which the majority of superficial lymphatics of the lower limb end. 14, 14. Superior inguinal glands. 15, 15. Inferior inguinal glands; their afferent and efferent vessels. FIG. 38. The superficial lymph- atics of the internal surface of the lower limb (after Sappey). THE LYMPHATICS OF THE LOWER LIMB 123 trunks then run upwards, being grouped round the internal saphenous vein to which they run parallel ; for the most part they are placed either in front of or behind this vein ; some of them may, however, cover it, or even be inserted between its deep surface and the aponeurosis. They thus pass as far as the inguinal glands. The external collecting trunks arise from the three outer toes, from the outer two- thirds of the dorsal surface, and from the anterior half of its exter- nal border. Their arrangement is very different to that of the internal trunks. Instead of passing up vertically as the latter do, and being arranged in parallel columns, the external collecting trunks divide into secondary trunks which run in succession upwards and inwards to end in the internal collecting trunks. A comparison of fig. 38 with fig. 39 well shows the difference between the collecting trunks on the external and internal surface of the limb. (2) COLLECTING TRUNKS WHICH FOLLOW THE COURSE OF THE EXTERNAL SAPH- ENOUS VEIN. These vessels take origin from the posterior half of the external 1,1. Lymphatic network of the external border of the foot. 2, 2. Two trunks springing from it ; they pass backwards, and end in the popliteal glands. 3, 3. Lymphatic vessels of the dorsal surface of the foot coming from the toes and from the anterior portion of the plantar region. 4, 4. Vessels which cross the crest of the tibia, almost all of which come from one and the same trunk, which divides and subdivides ; they are sinuous and frequently anasto- mose in their course. 5, 5. These are also very sinu- ous vessels which pass in front of the knee. 6, 6. Vessels which skirt the antero-external part of the knee joint, they are also remarkable for their sinuosities. 7, 7; Lymphatic vessels coming from the posterior portion Fio 39 Superficial lymphatics of of the thigh. 8, 8. Trunks which course along the the external surface of the lower antero-internal surface of the th.gh. 9, 9. Trunks limb (after Sappey). which correspond to its antero-external portion. 10, 10. Large glands in which the majority of superficial lymphatic vessels of the upper limb end. 11, 11. Superior inguinal glands ; they are generally four in number, and are arranged in linear series. 12, 12. Other inguinal glands with afferent vessels. 124 SPECIAL STUDY OF THE LYMPHATICS border of the foot, and from the corresponding portion of the heel. From two to three in number, they run at first like the external saphenous vein between the external malleolus and the tendo Achillis, which they more or less closely embrace. Here they receive the lymphatics from the inferior part of the posterior surface of the limb. Always in close contact with this vein they are placed, like it, in the space between the two gastrocnemii. In the upper part of their course, they become sub-aponeurotic, and receive no more cutaneous branches. They terminate in the juxta-saphenous gland which is the most superficial of all the popliteal glands (vide p. 113). (3) COLLECTING TRUNKS FROM THE GLUTEAL REGION. The collecting trunks from the gluteal region may be divided into two groups, external and internal. (a) The external are the most important. They arise from the outer two- thirds of this region. They run at first do Avn wards, outwards and forwards ; they then turn round the great trochanter and eventually terminate in the supero-external group of superficial inguinal glands. (b) The internal collecting trunks only drain the inner third of the buttock. They unite with the vessels coming from the integuments of the anal region (vide p. 187). Like the latter, they run downwards and forwards, and turning round the upper part of the thigh they end in the supero-internal, and infero-internal groups of superficial inguinal glands. Deep Lymphatics. The deep lymphatics of the lower limb may with sufficient accuracy be styled, " satellites " of the blood vessels. They comprise a principal channel which at first follows the different arterial trunks of the leg, and then keeps close to the popliteal and the femoral vessels, and accessory channels, which are satellites of the obturator, ischiatic and gluteal vessels. THE PRINCIPAL CHANNEL. In the foot and in the leg, the deep lymphatics may therefore be divided into three groups : the pedal and anterior tibial lymphatics, the plantar and posterior tibial lymphatics, and the peroneal lymphatics. The pedal and anterior tibial lymphatics arise from the sole of the foot. The small trunks from which they originate spring from the deep plantar muscles. They unite into one or two trunks which run towards the dorsal surface of the foot, keeping close to the communicating branch between the external plantar and dorsalis pedis arteries. They then embrace the latter vessel THE LYMPHATICS OF THE LOWER LIMB 125 Femoral trunks Popliteal gland Popliteal trunks closely, and afterwards the anterior tibial. After being interrupted in the anterior tibial gland, they continue their course and never leaving the anterior tibial artery, terminate in the middle group of popliteal glands. In their course, they collect all the deep lymphatics of the dorsal surface of the foot and anterior aspect of the leg. The plantar and posterior tibial lymphatics appear in the sole ; they follow the two plantar arteries, then the pos- terior tibial, and terminate in the same glands as the pre- ceding. It is in these glands that the peroneal lymphatics, satellites of the vessels of this name, terminate. After being interrupted in the popliteal glands, all these vessels pass upwards, embrac- ing the femoral vein. The latter is usually accompanied by four or five trunks, some of which are placed in front and some internal to it. Ac- cording to our own observa- tions, one or two small glands may be met with, in the course of these vessels in the region of the middle of the thigh. These vessels terminate in the deep inguinal glands. Accessory Channels. The obturator lymphatics which arise in the adductor muscles, are placed in the obturator foramen, and terminate in the obturator gland when this is present, or in the middle gland FlG . 40 ^lDeep lymphatics of of the internal chain of the ex- the posterior surface of the limb (after Bourgery). ternal iliac group (vide p. 132). The ischiatic lymphatics, satellites of the artery of this name, i Posterior' tibial trunks Peroneal trunks Posterior tibinl trunks 126 SPECIAL STUDY OF THE LYMPHATICS end in a hypogastric gland ; this terminal gland rests on the anterior trunk of the internal iliac artery (vide p. 135). During their extra-pelvic course, the ischiatic vessels traverse some small glands placed below the pyriformis muscle (vide Bourgery, loc. cit. plate 82). The lymphatics of the gluteal region come from the gluteal and the pelvi-trochanteric muscles ; they terminate in an intra-pelvic gland, placed on the actual trunk of the artery, at the upper border of the great sacrosciatic notch (vide p. 135 and fig. 43). Like the preceding, they present in their course six to ten small interrupting glandular nodules (Mascagni, Sappey). ANASTOMOSES. The superficial and deep lymphatics are clearly independent of each other. Mascagni, however, saw one of the superficial trunks, a satellite of the internal saphenous vein, pierce the fascia lata in the middle third of the thigh and anastomose with the deep lymphatics (Mascagni, loc cit. tab. iv. fig. 2). Bonamy, Broca, and Beau figure a similar arrangement (loc cit., t. 11, plate 45, fig. 2). Sappey on the other hand, declares that he was never able to prove the existence of an anastomosis between the superficial and the deep lymphatics. It is, however, important to notice that the efferent vessel which the popliteal glands send to the superficial inguinal glands (vide p. 114) constitutes a true anastomosis between the deep and the superficial lymphatics. This exception, however, does not invalidate the rule, and as a general proposition we may still maintain the independence of the superficial and deep lymphatic apparatus. Technique 1 We will now describe in detail the mode of injecting the lymphatics of the lower limb ; we will in fact indicate, in connection with this subject, the general rules which govern the injection of the superficial and deep lymphatics of the limbs, and the walls of the splanchnic cavities. Sappey laid down minute rules for the injection of the lymphatics of the lower limb with mercury. We will now merely reproduce his instructions, and then add a few words on the application of Gerota's method to the lower limb in particular. We will consider in turn the injection of the superficial and the deep lymphatics. The Superficial Lymphatics. To inject the superficial lymphatics, it is important to select a somewhat spare subject, aged from about fifteen to twenty. Wet compresses are first applied to the foot, to provoke a certain amount of maceration of the epidermis. The latter is then raised by scraping the skin with a convex scalpel. This removal of the softened epidermis by scraping is of the utmost importance; its object being to pre- 1 On General Technique, vide p. 1118. THE LYMPHATICS OF THE LOWER LIMB 127 vent the blocking of the mouth of the injection tube, which is bound to take place if the horny layer is left in place. A column of 30 to 40 centi- metres of mercury is used. The first punctures are made on the lateral aspects of each toe, at the junction of the second and third phalanges. The puncture should be entirely superficial, and should hardly reach the subpapillary layer of the skin. If the point has been well directed, we shall immediately see a small ash coloured spot appear round the punctured point, which shows that the mercury has penetrated the lymphatic network. If, at the end of a few moments, this characteristic spot does not make its appearance, it is useless to persist, and a fresh puncture must be made. It is important, however, not to make too many punctures, for each one opens up the network of origin, and thus causes a number of very small leakages, through which the mercury escapes. After the injection of the toes, the sole of the foot must be punctured at many points, and more especially in the neighbourhood of its external and internal borders. In this way the networks of origin and the trunklets which arise therefrom may be filled without much difficulty. Sometimes the mercury may actually be seen to pass into the large collecting trunks, and reach the inguinal glands; but it is usually impossible to succeed in injecting the entire lym- phatic system of the lower limb at the first attempt. In this case one of the trunks originating from the toe must be sought for by carefully removing the skin from the dorsal surface of the foot, and the collecting trunk thus found must then be injected. The same process may be repeated on one or several of the trunks which spring from the external and internal borders of the foot, and in this way almost all the collecting trunks of the lower limb may be filled. The skin is next carefully removed from the limb, working from below upwards, and the vessels now filled with mercury are dissected, the usual rules being followed (vide pages 59 and 60). The limb is then allowed to dry in the horizontal position ; but when the drying process is almost completed, the vertical position must be maintained. In order to inject the superficial lymphatics by Gerota's method, we pro- ceed in the same way as for the injection by mercury. The sudden appear- ance of a blue tinge round the puncture will shew that the injected material has passed into the networks. We should remark that in this particular case, the method of Gerota has no great advantages over mercury, except perhaps in newborn subjects, in which we can, in certain favom'able cases, obtain an injection of almost all the superficial lymphatics of the lower limb by making two or three punctures. Deep Lymphatics. The injection of the deep lymphatics is a much more delicate process, for with mercury, at any rate, it is practically impossible to fill them by direct puncture of their networks. To inject them we use Mascagni's method. A young and somewhat spare subject is selected for preference, into whose arteries and veins an injection of gelatine is made. The injected mass to some extent always transudes through the vascular walls and penetrates into the lymphatic vessels, which it renders more apparent ; one of the latter is then punctured directly, and very hot water run over the preparation to liquify the gelatine. The mercury then penetrates into the deep vessels without difficulty. With Gerota's mixture, we may sometimes fill the deep lymphatics by directly puncturing the fleshy portion of the different muscles, or by 128 SPECIAL STUDY OF THE LYMPHATICS superficially puncturing certain tendons, such as the tendo Achillis, for ex- ample; but we must recognize the fact that these injection trials made through the medium of the networks of origin, usually end in failure ; on the other hand, it is relatively easy to inject the satellite trunks of the femoral vessels by directly puncturing one of the popliteal glands. CHAPTER II LYMPHATICS OF THE PELVIS AND ABDOMEN WE will study (1) the glandular groups of the pelvis and abdomen ; (2) the lymphatic apparatus of the different organs, the vessels of which are the tributaries of these glands. 1. GLANDULAR GROUPS OF THE PELVIS AND ABDOMEN Though the lymphatic glands of the pelvis are continuous without line of demarcation with the abdominal glands, we will divide them, for convenience of our description, into two groups, separated by an imaginary horizontal line passing through the bifurcation of the aorta ; an inferior group (ilio-pelvic) ; and a superior group (abdomino-aortic). 1. ILIO-PELVIC GLANDS. Under the name of ilio-pelvic glands, we will describe the glands situated within the pelvic cavity or placed at the junction of the latter with the iliac fossae, at the level of the inlet of the true pelvis. Generally speaking, the ilio-pelvic glands are disposed fairiy regularly round the vessels. This paravascular arrangement enables us to divide them into three large groups : namely the external iliac glands, which run by the side of the vessels of this name ; the hypogastric glands, scattered along the trunk and branches of the internal iliac artery ; the common iliac glands placed round the vessels of the same name. The older writings only furnish us with very incomplete and often incorrect ideas on the topography of the glands of the pelvis. Quite recently, Marcille arid one of the authors have undertaken the study of these glands, and have given a new classification, which we here adopt. Vide : Cuneo and Marcille, Topographic des ganglions ilio-pelviens. Comrmmic Soc. anat., decembre, 1901. Marcille, Lymphatiques et gan- glions ilio-pelviens. Th. Paris, 1902. 130 SPECIAL STUDY OF THE LYMPHATICS 1. The External Iliac Glands. The glands grouped round the external iliac vessels usually present a constant arrangement. We may regard them as forming three chains which are more or ' less continuous, viz. an external, a middle, and an internal chain. 1 A. THE EXTERNAL CHAIN. The external chain comprises three hypogastric artery FIG. 41. Ileopclvic glands (Cuneo and Marcille). a. Right juxta-aortic gland. 6. Gland of the promontory. c. Common iliac gland, (middle group). d and e. External iliac glands (external chain). /. Hypogastric gland. g. External iliac gland (external chain). h. Left juxta-aortic gland. i, j. Common iliac glands. Jfc.External iliac gland (external chain). /, ra. External iliac glands (middle chain). n. Retro-crural external gland. o. Obturator gland. x To thoroughly grasp the topography of these glands we must recall the position of the external iliac vessels. The artery and vein do not lie, as is too often stated, on the psoas muscle ; they are clearly internal to it, and lie on its inner border, overhanging the pelvic cavity. LYMPHATICS OF THE PELVIS AND ABDOMEN 131 to four glands which shew a tendency to insinuate themselves between the internal border of the psoas, and the external iliac artery. The lower gland of this chain is placed immediately behind the crural arch. It lies on the terminal portion of the external iliac artery, and covers the origin of the deep circumflex iliac and the deep epigastric arteries. It is underneath this gland, that the genito-crural nerve divides into its two terminal branches. This gland may be called the external retro-crural gland. It is usually a fair size ; sometimes it is replaced by two smaller glands, the more internal of which then represents the commencement of the middle chain. The overlying glands are lodged in the interspace which separates the external iliac artery from the internal border of the psoas. B. MIDDLE CHAIN. The middle chain comprises two or three glands placed on the anterior surface of the external iliac vein. When there are three glands, the lowest is situated immediately behind the crural arch. We may term it the middle retro-crural gland. It is inconstant. It is in fact most usually fused with the adjacent gland of the preceding chain. The middle gland is usually situated midway between the crural arch and the bifurcation of the common iliac artery. As regards the superior gland, it is placed immediately in front of the origin of the internal iliac artery, and is often covered by the ureter. These two glands, i.e. the middle and superior of the middle chain, sometimes show a ten- dency to become situated on the internal surface of the vein, and are almost intrapelvic. C. INTERNAL CHAIN. The internal chain comprises three to four glands and is placed below the external iliac vein, against the lateral wall of the pelvic cavity, above the obturator nerve. The inferior gland of this chain is situated immediately behind the external or lymphatic portion of the crural ring, and lies upon the terminal por- tion of the ilio-pectineal line. It is placed next to the gland of Cloquet, or when this is absent, to the chain of deep inguinal glands. It may be styled the internal retro-crural gland. The suprajacent gland (the middle gland) is remarkable for its size and constancy ; it is elongated like a spindle, and situated on a slightly lower plane than the former, as though its weight were dragging it down into the pelvic cavity. It lies immediately above the obturator nerve. The third gland (superior gland) is usually smaller, and is placed behind those already mentioned, in front of the trunk of the internal iliac artery. 132 SPECIAL STUDY OF THE LYMPHATICS This chain may be reduced to two or even a single gland, by fusion of its constituent elements, in which case an enormous elongated gland may be found lying on the lateral wall of the pelvis; extending from Gimbernat's ligament to the hypogastric artery. Most authors regard this internal chain as belonging to the group of hypogastric glands, but we think this view has many inconveniences. Though prolapsed into the pelvis, this chain is obviously continuous with the deep inguinal glands, and remains a satellite of the external iliac vein. As figures 42 and 43 well show, it forms an integral part of the strong lym- phatic current which runs upwards from the lower limbs towards the lumbar region. Further, as we shall see later on (vide p. 133), its pelvic affluents are relatively few, and are much less impor- tant than its afferent femoral lymphatics. Obturator Gland. In the above-mentioned chain may be included a small inconstant gland placed beneath the obturator nerve, on the actual level of the internal surface of the obturator foramen. This gland, which receives the deep lymphatics, the satellites of the obturator vessels, is attached by its efferents to the lower bor- der of the large middle gland of the internal chain (vide Fig. 41). It is to this gland that the name of obturator should be confined. This question regarding the obturator gland has given rise to numerous discussions. It was Cruveilhier who first insisted on the existence of a gland at the level of the internal orifice of the obturator foramen. " I shall regard as constant a fair-sized gland which occupies the internal orifice of the oval canal and which I have frequently seen inflamed or indurated in maladies of the uterus. It may be styled the gland of the oval foramen." Bouilly, and A. Guerin admitted the existence of this gland, and described its afferents as coming from the uterus, and considered that it played an important part in the pathogeny of certain varieties of phlegmenous parametritis. Sappey, on the contrary, does not mention any gland at the entrance of the obturator foramen. As one of the present writers long since observed, it is certain that normally no gland exists at this spot. The existence of the little gland mentioned above must be regarded as an anomaly, the frequency of whose presence it is most difficult for us to estimate. When this little glandular nodule is absent, the gland nearest to the obturator foramen is our middle gland of the internal chain, which is situated about 15 to 20 millimetres behind and above the entrance to the canal. It is to this gland that Cruveilhier must have alluded. The " voluminous and constant " gland of which he speaks cannot be this minute and often absent gland which we have just noted. It is moreover important to add at once that the middle gland of the internal chain receives no lymphatics coming from the uterus (vide Uterine lymphatics pp. 163 and 164). BIBLIOGRAPHY. Cruveilhier, Anatomie descriptive, 3 e Edition, t. Ill, LYMPHATICS OF THE PELVIS AND ABDOMEN 133 p. 154. Guerhi, Bull, de V Ac. de med., 1887, p. 533. Cantin. Des lym- phangites periuterines non puerperales. Th. Paris, 1889. Poirier. Lym- phatiques des organes genitaux de la femine. Procjres medical, 1890. Poirier et Picque. Etude sur la hernie obtura trice. Revue de Chirurgie 1891 t. XI, p. 693. AFFERENT VESSELS. Each of the three chains receives distinct affe rents. 1. External Chain. The majority of lymphatics which eventually terminate in the external chain, end in the inferior gland of this chain (the retro-crural gland). The other glands of the external chain simply constitute a second relay interposed in the course of afferents of the preceding gland. This external retro-crural gland receives (a) Some of the efferents from the superficial and deep inguinal glands. (b) The lymphatics from the glans or clitoris, which come to this gland per the inguinal canal. (c) Some of the deep lymphatics from the sub-umbilical portion of the abdominal wall ; these are satellites of the deep epigastric and deep circumflex iliac arteries (vide p.^151 and Fig. 50). 2. Middle Chain. When the middle chain is reduced, as is usually the case, to two glands only, the inferior gland receives at first a double pedicle which comes to it from the external and internal retro-crural glands (vide Fig. 42). Vessels from the bladder, pros- tate, neck of the uterus, and from the upper portion of the vagina end in this chain. 3. Internal Chain. This chain receives numerous afferents, which may be divided in the following way (a) Efferent vessels from the superficial and deep inguinal glands. (b) Deep collecting trunks from the glans and clitoris, which pass via the crural canal. (c) Deep collecting trunks from the umbilicus and subumbilical portion of the abdominal wall. (d) Lymphatic satellites of the obturator vessels coming from the adductor muscles of the thigh. (e) Lymphatics from the neck of the bladder, the prostate, and membranous portion of the urethra. (/) Some efferents from the hypogastric glands, and more par- ticularly from the middle haemorrhoidal gland. As we have seen, the three external iliac chains receive lymphatics coming from the inguinal glands. The external and internal chains I** 134 SPECIAL STUDY OF THE LYMPHATICS receive these vessels directly ; the middle chain only receives them after they have been interrupted in the external and inter- nal retro-crural glands. It seems that the strong lymphatic current, which has its source in the lower limb, divides, in the region of the external iliac vessels into three secondary currents, corresponding to each of our three glandular chains. On the other hand, the middle and internal chains are the only ones to receive lymphatics coming from the true pelvis. We may be surprised at this arrangement, whereby the middle chain, placed at the level of the inlet, receives lymphatics from the pelvic cavity and also from the prostate or vagina. The fact is, that these vessels have a somewhat long course to pursue before arriving at the middle chain, and it may appear singular Miat they are not arrested in the internal chain, which they are compelled to cross. Their termination in the middle chain is ex- plained by their development. In the foetus, as is well known, the prostate and vagina occupy a much higher position than in the adult, and are placed at the actual level of the inlet. Their lymphatics have therefore only a very short course to pursue before reaching the middle chain. Later on. when these organs sink into the pelvic cavity, these vessels secondarilv acquire a longer and more complicated course. We shall see an analogous but much more striking phenomenon manifest itself in the lymphatics of the ovary and testicle. EFFERENT VESSELS. Each gland belonging to these different chains sends its efferents to the gland above it, so that the highest gland of the chain continues the lymphatic circulation of those placed below it. The efferents of the superior gland of the external chain terminate in the inferior gland of the external group of the common iliac glands. The efferents of the superior gland of the middle chain are divided into two groups: the external and the internal; the first, which is the most important, joins with the efferents of the external chain ; the second joins the efferents of the internal chain. The efferents of the internal chain are placed beneath the trunk of the internal iliac artery, and become united to the efferents of the hypogastric glands, and eventually terminate, like the latter, in the middle group of the common iliac glands (the group placed in the fossa for the lumbo-sacral nerve). Epigastric and Circumflex Iliac Chain. Two secondary chains should be included with the external iliac glands, viz. the deep epigastric and deep circumflex iliac chains. LYMPHATICS OF THE PELVIS AND ABDOMEN 135 The epigastric chain comprises three to six little glands placed over the course of the lower third of the deep epigastric artery. These glands, the size and number of which is very variable, may be wanting. The circumflex iliac chain comprises two to four little glands placed over the artery of this name. They are even smaller than those of the preceding group, and are very frequently absent. 2. The Internal Iliac or Hypogastric Glands. The hypogas- tric glands are connected to the branches of the artery of this name. Their number is somewhat variable. They are placed 12 FIG. 42. Scheme of the ileo-pelvic glands (Cunco and Mamllc). 1 and 1 bis. Inferior glands of right and left lateral-nortic groups. 2. Common iliac group (external group). 3. Middle band of external chain of external iliac glands. 4. Retn>- crural external glar.d.- 5. Gland of the middle chin of external iliac glands. C.~Glo,nd in fossa for the lumbo-sacral nerve. 7 and 7 bis. Group of the promontory; on th* right, the gland is beneath the left common iliac vein ; on the left, one of the glands is in front of the same vein. 8. Lateral sacral group. 9. Hypogastric group. 10. Gland of the internal chain of external iliac glands. 11. Retro-crural internal gland. 12. Deep inguinal gland. 13 and 14. Superficial inguinal glands. near the origin of the different branches of the internal iliac artery, in the angles formed by their separation. The most anterior of these glands is placed between the hypogastric (umbilical) and the subjacent artery, which is usually the obturator. The most posterior is placed on the trunk of the gluteal artery. The others are placed between the two preceding and unite them., describing a fairly regular curve, the concavity of which points upwards and forwards. The arrangement of these intermediary 136 SPECIAL STUDY OF THE LYMPHATICS glands is somewhat inconstant. However they are generally arranged as follows The first is placed in the neighbourhood of the uterine or pros- tatic artery ; the second, which is more posterior, rests on the common trunk of the sciatic and pudic ; a third, placed apart from the preceding, is situated oh the middle haemorrhoidal artery ; it usually corresponds to the point at which this artery breaks up into its terminal branches, and is nearly in contact with F IG . 43. Ileo-pelvic glands (lateral view) (Cuneo and Marcille). a and 6. External iliac glands (middle chain). c. External iliac gland (external chain). d. Retro-crural external gland. e. Retro-crural internal gland./, g. Lymphatics of the bladder. h. Collecting trunks from the mucus membrane of the glans passing through the inguinal canal. i. Praesymphysinl glandular nodule./. Gland of the promontory o T?" 1361 glutCal land ' L Latcral sa "'l gland. m, r.. Hypogastric glands. o. Satellite trunk of internal pudic vessels. p. Middle haemorrhoidal trunk. q, r. Prostatic collecting trunks. s. Urethral collecting trunks. the lateral wall of the rectum (middle haemorrhoidal gland). There is one more group, even more isolated, which is formed by two or three glands situated internal to the second or third sacral foramina, and on the course of the lateral sacral artery (lateral sacral gland).' LYMPHATICS OF THE PELVIS AND ABDOMEN 137 All these glands rest on the inner surface of the pelvic fascia, and to show them, we need merely raise the peritoneum. Sometimes they are placed on the external surface of this aponeurotic layer, as may be seen when the latter is dissected off from the lateral wall of the pelvis. All these glands are united to each other by numerous anastomoses. AFFERENT VESSELS. The hypogastric glands receive afferents from all the pelvic viscera. We may thus see, ending in this glandular group, lymphatics from the membranous and prostatic portions of the urethra, prostate, bladder, vesiculae seminales, vasa deferenti a, vagina, uterus, and rectum. All these vessels are more or less satellites of the branches to the different viscera, given off by the internal iliac artery. They also receive the collecting trunks of the sub-aponeurotic portions of the perineum, the lymphatics from the penile portion of the urethra, and, according to the researches of Marcille, even certain trunks from the anus. These vessels follow the course of the internal pudic artery and its branches. Finally, the deep lymphatics from the posterior surface of the thigh and gluteal region, satellites of the sciatic and gluten] vessels may be seen to terminate in these glands. EFFERENT VESSELS. The efferents of the hypogastric glands are directed upwards and outwards, and passing underneath the common iliac vein, terminate in the middle group of the common iliac glands. We shall see later on that this group, which is situ- ated underneath the vessels, in the fossa for the lumbo-sacral nerve, itself sends its efferents to the inferior part of the lateral aortic chain of the corresponding side. 3. The Common Iliac Glands. - The glands grouped around the common iliac artery may be divided into three groups, viz. an external, a middle, and an internal. The external group generally comprises two glands, which are placed external to the artery and which lie on the internal border of the psoas. This group is continuous with the external chain of the external iliac glands, and is continuous above without any line of demarcation with the juxta-aortic group of the corresponding side. The middle group (deep or retro- vascular) is made up of two to four glands, which are entirely hidden behind the vessels. These glands occupy a fossa which has recently been well described by Marcille, and which is constituted as follows : Internally, it is limited by the body of the 5th lumbar vertebra ; externally, by the internal border 138 SPECIAL STUDY OF THE LYMPHATICS of the psoas. Its base is formed by the upper border of the wing of the sacrum. This fossa is covered by the common iliac vessels, which tend to sink down within it. It is in the fat which fills this fossa, above the lumbo-sacral and obturator nerves which occupy its base, that we find the retro- vascular glands. The internal group, with that on the opposite side, constitutes an uneven and mesially placed group in front of the body of the 5th lumbar, or on the disc between this and the sacrum. We may call it the group of the promontory. It is sometimes formed of two fairly distinct masses : one, the inferior and on the right side, lies underneath the left common iliac vein (subvenous collec- tion) ; the other, the superior and on the left, lies on this vein (prae venous collection), vide Figs. 41 and 43. AFFERENT VESSELS. The external and the middle groups of the common iliac glands do not really receive any vessels ema- nating directly from the neighbouring organs. On the contrary, they form the terminus for the numerous and large efferents of the three external iliac chains and of the hypogastric glands. The internal group or group of the promontory, receives (1) certain efferents from the lumbo-sa'cral group ; (2) vessels coming from the majority of the pelvic organs ; in fact, the lymphatics from the prostate, neck of the bladder, neck of the uterus, vagina, and perhaps also from the rectum, terminate in this group. The collect- ing trunks of the right side end in the subvenous glands, those on the left in the praevenous glands. All these vessels clearlv take the same course (vide Figs. 55, 58, 68). At their commence- ment they are attached to the pelvic floor, they then ascend into the concavity of the sacrum, and passing slightly external to the middle line, reach the gland of the promontory, after pursuing a long course which on the whole describes a fairly regular curve. EFFERENT VESSELS. The efferents of the three common iliac groups converge towards the inferior part of the lateral aortic chain of the corresponding side. All the ilio-pelvic lymphatics finally end therefore in the two right and left juxta-aortic chains. The inferior gland of these two chains represents the point of convergence of all the efferents of the glandular groups which we have just been studying. On the one hand, it receives the efferents of the external group of the common iliac glands which itself comprises the internal and middle chains of the external iliac glands. On the other hand, it receives the efferents of the group of the promontory, and the glands in the LYMPHATICS OF THE PELVIS AND ABDOMEN 139 lumbo-sacral fossa; and, as we have already seen, the latter is the terminus of the afferent vessels of the hypogastric glands and of the internal chain of the external iliac glands. There is then, in the lower portion of the lumbar region, a simplification of the lymphatic channels ; they are reduced to two large lateral ascend- ing currents ; from this point it is true, we shall see a new current, uneven and median, making its appearance, the origin of which is entirely different, inasmuch as it conveys the lymph from the intestinal portion of the digestive canal. 2. ABDOMINO-AORTIC GLANDS The abdomino-aortic glands, which number from twenty to thirty, are grouped around the abdominal aorta. Basing our classification on their relations to this trunk, divide Intffititif Prce-aortic g land. ' Left juxta-aortic gland. Right ji'.rt'i-'">rfic praevenoits Renal gland. Retro-aortic gland. Right juxta-aoriic retrovenous gland. . Inf. cava. arterial we may them into four groups : (1) The left juxta- aortic glands; '(2) Aorla The right juxta- aortic glands ; (3) The prae - aortic glands; (4) The retro - aortic glands. Each of these groups possesses a special lymphatic territory." The juxta-aortic glands receive the efferents of the common iliac glands, as well as the parietal lymphatics, and the lymphatics of the kidneys and genital glands. In the prae-aortic glands, the lymphatics from the digestive canal and its accessories more especially terminate. As regards the retro-aortic glands, they receive but few vessels coming directly from the abdominal vis- cera they constitute a fresh relay interposed in the course of certain efferent vessels of the preceding groups, before vessels join the thoracic duct. 1 Left Juxta-aortic Glands. The left juxta-aortic glands form an almost continuous vertical chain, which runs along the left flank of the abdominal aorta. This chain reposes on the vertebral p IG . 44. Transverse section (diagrammatic) showing the general arrangement of the abdomino-aortic glands. 140 SPECIAL STUDY OF THE LYMPHATICS attachments of the psoas muscle and on the left pillar of the dia- phragm ; it is crossed on its anterior surface by the left renal artery and vein. Afferent Vessels. These glands receive : (1) the efferent lym- phatics of the common iliac glands ; (2) the satellite lymphatics of the lumbar arteries, which come from the large abdominal muscles ; 7 _. FIG. 45. Abdomino-aortic glands in the new-born infant (after Cuneo). 1. Left supra -renal capsule. 2. Left spermatic vein. 3. Left juxta-aortic gland. 4. Inferior mesenteric. 5. Hypogastric artery 6. Rectum. 7. Inferior phrenic artery. 8. Superior mesenteric artery. 9. Right juxta-aortic gland. 10. Ureter. 11. The posterior gland of the middle chain of the external iliac group. (3) the lymphatics from the left testicle in the male, from the left annexa and corresponding half of the body the uterus in the female ; (4) the lymphatics of the kidney and the left supra-renal capsule. LYMPHATICS OF THE PELVIS AND ABDOMEN 141 Efferent Vessels. The efferent vessels of the left juxta-aortic glands may be divided into four groups. Some of them empty their contents into the prae-aortic glands ; others end in the retro- aortic glands ; while others, more numerous, unite into a common trunk which ends in the receptaculum chyli ; others finally, traverse the left pillar of the diaphragm and empty their contents into the thoracic duct a little above its origin (vide fig. 114). Some of these vessels are sometimes interrupted by glands placed between the posterior surface of the pillar of the diaphragm and the vertebral column. 2. Right Juxta-aortic Glands. The right juxta-aortic glands are placed some in front of the inferior vena cava, others behind it. There is a sort of adjustment between these two groups, so that when one of them is well developed, the other is, generally, sensibly reduced. The prae-venous glands, from 3 to 6 in number, are usually found underneath the junction of the renal veins with the inferior vena cava. The retro-venous glands rest, as do the left juxta-aortic glands, on the origins of the psoas muscle and on the anterior surface of the corresponding pillar of the diaphragm. Afferent Vessels. The right juxta-aortic glands receive the same affluents as the homologous group of the other side. It is interesting to note that the genital lymphatics especially pass to the prae-venous glands, and the parietal lymphatics to the retro- venous glands. As regards the lymphatics of the kidney, they are divided between the two groups, as we shall see later on. Efferent Vessels. The efferents of the right juxta-aortic glands terminate in the same way as the juxta-aortic glands of the opposite side. 3. Prae-aortic Glands. These glands sometimes form, at least in the new-born infant, a continuous chain situated on the anterior surface of the aorta ; but most frequently they are grouped into three distinct masses, viz. an inferior, middle, and superior, placed on the origin of the three large trunks which the aorta sends to the abdominal portion of the digestive canal. (a) The inferior mass is usually formed by two glands, which are elongated vertically and symmetrically placed on either side of the origin of the inferior mesenteric artery. In these glands terminate the lymphatics from the rectum, ileo-pelvic colon, and the ascending colon. These vessels, as we shall see later on (p. 191) have moreover already traversed one or two glandular relays. 142 SPECIAL STUDY OF THE LYMPHATICS (b) The middle mass is made up of a large collection of glands sur- rounding the origin of the superior mesenteric artery, and con- tinuous without line of demarcation with the glands placed at the root of the mesentery. This mass receives the lymphatics coming from the small intestine, coecum, appendix, ascending colon, trans- verse colon, and pancreas. (c) The superior mass is formed by one to three glands placed above the coeliac trunk. It is continuous without line of demarca- tion with the three chains : hepatic, coronary, and splenic, which are, so to speak, outward prolongations from it. Afferent Vessels. The prae-aortic glands receive certain efferents from the juxta-aortic group ; but almost all their afferents are formed by vessels coming from the glandular groups, in connection with the mesenteric arteries or the coeliac trunk, and which receive the lymphatics of the intestine, the stomach, the liver, the pancreas, and the spleen. Efferent Vessels. The three prae-aortic glandular masses are joined together by numerous vessels. The efferent trunks to which these glands give origin turn round the lateral parts of the abdo- minal aorta. Their mode of termination varies at different levels. The inferior terminate in the retro-aortic glands subjacent to the receptaculum chyli. The superior end in this receptaculum. Though they sometimes terminate separately into the latter, they most commonly unite into a common trunk (truncus intestinalis), which runs side by side with the common trunk formed by the efferents of the left juxta-aortic group, and which simultaneously with the latter empties its contents into the receptaculum chyli. In the prae-aortic group may be included all the glands placed on the various branches given off by the abdominal aorta to the subdiaphragmatic portion of the digestive canal. We shall there- fore have to study (1) The glands situated in the course of the two mesenteric arteries. (2) The glands attached to the branches of the coeliac axis. (1) THE GLANDS ATTACHED TO THE MESENTERIC ARTERIES. The glands attached to the two mesenteric arteries seem at first sight to be irregularly scattered over the course of these arteries and their branches : their general arrangement however is sufficiently definite to enable us to attempt its classification. Some of these glands are placed beneath the last series of arches which the arterial branches destined for a given segment of intestine form by their anastomosis. These glands, thus attached to the LYMPHATICS OF THE PELVIS AND ABDOMEN 143 terminal arterioles, are very close to the intestinal insertion of the mesentery, and we may call them the juxta-intestinal glands. Nearly always of small size, they rarely retain artificial injections, and in the case of cancers only arrest the neoplasmic elements for a short time. They are therefore comparable to those small glands which we have already had occasion to notice on the course of the lymphatics of the various organs, which the Germans call " Schaltdriisen " (vide p. 86). These glands present no mor- phological fixity, and their number varies considerably in different subjects. Other glands, which are larger and more constant in their presence ffc:>,, -. itffSn.^ .-3 FIG. 46. Glands of the small curvature and the subpyloric glands in the new-born infant. 1. Praecardiac glands. 2. Glands of the small curvature. 3. Subpyloric glands. and situation, are placed in the course of the primary branches of the mesenteric arteries. They constitute the true regional glands of a definite segment of intestine. Others, finally, are placed round the principal trunks of these vessels. They represent the glandular centres, which are usually common to many segments of the intestine. They receive the efferents from the preceding glands. For the present we will rest content with these general data, and to avoid useless repetitions, we will study the exact topography of 144 SPECIAL STUDY OF THE LYMPHATICS these glands when we deal with the lymphatics of the different intestinal segments with which they are connected. (2) GLANDS CONNECTED WITH THE BRANCHES OF THE COELTAC Axis. The glands connected with the branches of the coeliac axis are arranged in three chains : viz. the coronary or gastric, the splenic, and the hepatic. In the latter we shall include the bile duct chain. (1) THE CORONARY OR GASTRIC. The glands of the coronary chain may be divided into two groups : the group of the falx of the coronary artery, and the group of the small curvature. (A) The group of the falx is formed by glands situated by the side of the artery as it runs in the gastro-pancreatic ligament. They vary from two to six in number. They are never entirely absent. (B) Under the term of group of the small curvature, we will in- clude all those glands which are placed either on the trunk of or on the branches of the coronary artery after the latter has reached the stomach. These glands form two principal masses. (a) Some accompany the left or ascending branches of the artery. They form a primary mass, which corresponds to the vertical portion of the small curvature, and to the gastric insertion of the thickened portion of the gastro-hepatic omentum. With these glands we may include two smaller masses, placed one on the anterior surface, and the other on the posterior surface of the cardia. These two masses the prae- and retro-cardiac are sometimes joined, accord- ing to Sappey, by a gland placed on the left of the cardia. This left juxta- cardiac gland is, however, generally absent. (6) The secondary mass is formed by glands placed on the course of the large right or descending branches of the gastric artery. These are usually grouped near the spot where the coronary ap- proaches the border of the stomach. It is very rare to meet any of them in that part of the small curvature which corresponds to the pylorus and the pyloric vestibule. All these glands are placed between the two layers of the small omentum, in the midst of the dense network formed by the interlacing of branches of the coronary artery and the left pneumogastric nerve. The coronary gastric glands receive as afferents the lymphatics coming from the stomach, As we shall see later on, their region is very extensive and constitutes the most important of the various lymphatic territories of the stomach. Their efferent vessels ter- minate in the prae-aortic glands which surround the coeliac axis. (2) SPLENIC CHAIN. The splenic chain comprises a very variable number of glands (four to ten), which accompany the artery of this LYMPHATICS OF THE PELVIS AND ABDOMEN 145 name. Like the artery, they are situated on the posterior surface, and near the superior border of the pancreas. The extremity of this glandular chain is contained in the pan- creatico-splenic omentum. The afferent vessels of these glands come from the spleen, FIG. 47. General view of the porastomachic glands in the- new-born infant. The stomach has been cut in the middle, and the two halves have been drawn aside one to the right, and the other to the left, to show the origin of the coeliac axis. The liver is raised, and the transverse colon drawn well downwards and forwards, 1. Glandular group of the coeliac axis. 2. Splenic chain. 3. Group of the falx of the coronary artery. 4. Retro-pyloric group. 5. Sub-epipyloric group. 6. Glands of small curvature. 7. Mesccoiic glands. 8. Glands at the root of the mesocolon, seen through the mesocolon. 9. Gland of the liiium of the iiver. 10. Middie colic artery. li. Umbiiicai vein. 12. Pyloric vessels. 13. Right gastro-epiploic vein passing into the middle colic vein. *, Point at which the gastroduoclenal artery should bo tied when the retropyloric glands are extirpated. the pancreas and fundus of the stomach. The efferent vessels terminate in the glands which are placed on the coeliac axis. (3) THE HEPATIC CHAIN. The hepatic chain comprises three to six glands which are situated in the course of the hepatic artery. Some of these glands are placed on the horizontal part of this vessel, and consequently correspond to the superior border of the pancreas and to the floor of the foramen of Winslow. Others are situated on the vertical portion of the artery, and correspond with the left side of the portal vein. These glands receive the lymphatics of the liver and K 146 SPECIAL STUDY OF THE LYMPHATICS send out efferents which terminate in the glands which surround the origin of the coronary trunk. The hepatic chain gives off a secondary chain which is a satellite of the right gastro-epiploic artery. This gastro-epiploic chain comprises two distinct glandular groups, viz., the subpyloric and retropyloric group. (A) The subpyloric group on an average comprises three to six glands, which are placed between the layers of the great omentum, beneath the pyloric zone of the stomach. It is rare to find glands in the middle portion of the great curvature, and quite exceptional to meet with them in the region of the fundus. The relation of these glands to the gastro-epiploic vessels is somewhat variable ; usually they are subjacent ; in some cases, however, they may be placed between the vessels and the stomach ; but it is exceptional to see them in close contact with the stomach, as is the case with the glands of the small curvature. Thus, in cases of cancer they are not blended with the growth in the pylorus until a well marked invasion of the great omen- tum has taken place. In the subpyloric group may be included some aberrant glands, which are placed between the layers of the great omentum, along the descending branches of the gastro-epiploic arch. These glands, which are as variable in number as in arrangement, may be more than 5 to 6 centimetres distant from the great curvature. We can well understand how they may escape notice and be left in situ, during a gastrectomy, unless their increase in size renders them apparent. The subpyloric glands receive as afferents the lymphatics coming from the inferior region of the stomach (vide pp. 197, 198 and Fig. 73), or the upper part of the great omentum. Their efferent vessels follow the course of the right gastro-epiploic artery and ter- minate in the retro-pyloric glands, but we may often see one or more of these efferents end in the glands which surround the superior mesenteric vessels, where the latter cross the third portion of the duodenum. These collecting trunks then follow the right gastro-epiploic vein, which, as we know, frequently joins the sub- pancreatic portion of the superior mesenteric, either directly, or by a trunk common to it and the middle colic vein (vide Fig. 47). (B) The retro-pyloric group usually comprise two to three glands which are continuous with the preceding, and are also continuous, with- out any line of demarcation, with the glands of the principal hepatic chain. These glands, placed round the trunk of the gastro-duodenal. are in relation in front with the posterior surface of the pylorus, and behind with the pancreas. When they are degenerated they may be LYMPHATICS OF THE PELVIS AND ABDOMEN 147 firmly adherent to this organ from which it is difficult to separate them. This glandular group in not uncommonly absent. The retro-pyloric glands receive as afferents the trunks coming from the sub-pyloric group, some of the lymphatics coining from the posterior surface and superior border of the pylorus, and also the trunks coming from the first portion of the duodenum. THE GLANDULAR CHAIN OF THE CYSTIC AND COMMON BILE DUCT. 111 the course of the extra hepatic biliary ducts, we find a series of glands which are arranged vertically and whose direction is parallel to Gland of the hepatic cl.ain. Hepatic artery. Splenic vein. Superior m'senteric glcnd. Glun'ljol common~b\le duct; Client r>f common bile d'tct. Gastro-duoien'd artery. Retro-pancreatic gland. Port it vein. _ . ftstro-pancreatic gland. . _ _ . R"tro-pancr2tic gland. Fio. 48. Posterior surface of duodenum and pancreas. In this figure may be seen the glands of the hepatic artery, the cystic and common bile duct chains, and those corresponding to the vascular arch behind the pancreas. that of these ducts. The highest of these is none other than the cystic gland ; it is found in the angle which is open on the left, and which in front is bounded by the neck and body of the gall bladder. This gland which was pointed out by Mascagni, and since found again by Broca, is inconstant. The subjacent glands are arranged below one another along the course of the cystic and common bile 148 SPECIAL STUDY OF THE LYMPHATICS ducts, and are placed along the right-hand border or posterior surface of these ducts. Their number and exact arrangement has appeared to us to be somewhat variable. There is, however, one gland which is fairly constant, namely, that placed at the junction of the cystic and hepatic duct (Quenu). Inferiorly, this chain blends with the satellite chain of the vascular arch behind the pancreas. It may be seen therefore that in the hepatic pedicle there are two chains relatively distinct, one of which is a satellite of the two large biliary collecting ducts, while the other follows the course of the hepatic artery. Though this arrangement is not always met with, we think nevertheless it should be regarded as the usual type. (4.) The Retro-aortic Glands. The arrangement of the retro- aortic glands is much more variable than that of the preceding groups. From four to five in number they are placed in front of the 3rd and 4th lumbar vertebrae, immediately underneath the recepta- culum chyli. Sometimes, (six out of sixteen times) some small glands placed between the aorta and vena cava unite the retro-aortic group to the glands placed in front of these vessels. The retro-aortic glands receive the lymphatics coming from three of the preceding groups, viz. the prae-aortic and the right and left juxta-aortic groups. Their efferent vessels pass into the recepta- culum chyli. To sum up, the afferent vessels of the retro-aortic glands are almost entirely made up of the efferents of the prae and juxta- aortic glands ; these retro-aortic glands are not therefore true regional glands (vide p. 86), but simply constitute a fresh relay interposed between the preceding groups and the receptaculum chyli. Moreover, we must recollect that certain efferents of the preceding groups end directly in the receptaculum, or even in a suprajacent segment of the thoracic duct, by passing through the pillars of the diaphragm (vide Fig. 114). 11. THE LYMPHATIC VESSELS OF THE PELVIS AND ABDOMEN. We will now study the lymphatics of the abdominal wall, the lymphatics of the male and female external and internal genital organs, the lymphatics of the urinary organs, and finally the lymphatics of the subdiaphragmatic portion of the digestive tube and its annexa. I. THE LYMPHATICS OF THE ABDOMINAL WALL. We may divide the lymphatics of the abdominal wall into the LYMPHATICS OP THE PELVIS AND ABDOMEN 149 superficial or cutaneous lymphatics, and deep, aponeurotic or mus- cular lymphatics. (1) THE SUPERFICIAL LYMPHATICS may themselves be divided into anterior and posterior. (a) The anterior as they descend, converge towards the inguinal region and terminate in the supero-external and supero-internal groups of the superficial inguinal glands. The vessels which arise near the costal margin have however an entirely different ter- mination, inasmuch as they are tributaries of the axillary glands. (b) The posterior arise from the integuments of the lumbar region. Anastomosing above with the lymphatics of the back, and below with the lymphatics of the gluteal region, they give origin to three or four collecting trunks, which run downwards and forwards, coursing a little above and parallel to the iliac crest ; they terminate in the supero-external group of the superficial inguinal glands. (2) THE DEEP LYMPHATICS arise either from the different aponeur- oses, or from the fleshy portions of the different muscles of the ab- dominal wall. They group themselves into four principal channels ; (a) A channel which is a satellite of the deep epigastric artery, the con- stituent vessels of which, after traversing the epigastric glands, ter- minate in the external and internal retro-crural glands, (b). A channel which accompanies the deep circumflex iliac artery and ends in the external retro-crural gland, (c) A lumbar channel comprising four to five trunks, which are satellites of the lumbar arteries and tributaries of the juxta-aortic glands, (d) An ascending channel, which is a satellite of the abdominal branch of the internal mammary artery, the constituent vessels of which terminate in the internal mammary chain. There is one region of the abdominal wall where the lymphatics from a practical point of view, have a particular interest : this is the umbilical region. We will therefore devote a few lines to the study of the lymphatics cf the umbilicus. LYMPHATICS OF THE UMBILICUS. We may divide the lymphatics of the umbilicus into three groups : (1) The cutaneous lymphatics ; (2) The lymphatics of the fibrous nucleus ; (3) The lymphatics of the aponeurotic edge of the ring. (1) The cutaneous lymphatics arise in the foetus and in the newborn infant from the umbilical scrotum, and in the adult from the skin which covers the fibrous nucleus of the umbilicus. Their network of origin, which is extremely close, is continuous with that of the surrounding skin. From this network four or five trunks on either K* 150 SPECIAL S1TDY (JF THE LYMPHATICS side run downwards and outwards towards the centre of the inguinal region ; these lymphatic trunks run immediately beneath the in- teguments in a more superficial plane than the subcutaneous ab- dominal lymphatics, whose course they follow. They terminate in the supero - internal and supero-external groups of superficial inguinal glands (vide p. 116). It is exceptional to see these descending trunks cross one another in the middle line. On the other hand, vessels of the same side often cross each other, and one of the most internal trunks ma}' be seen to termin- ate in one of the more external of the superior inguinal glands (vide Fig. 51). On puncturing at the actual level of the umbilicus, we never really inject any vessel terminating in the axillary glands. To inject the tributary trunks of these glands, the puncture must be made at some distance above the umbilicus (Cuneo and Marcille). (2) The lymphatics of the fibrous nucleus, which are much more difficult to inject than the preceding, have an entirely different ter- mination. On each side of the nucleus, three to four trunks may be seen to arise which at once penetrate the sheath of the recti, and embrace the deep epigastric artery, which at this level is intra- muscular. Lower down, they are situated over the artery itself, between the muscle and the posterior part of its sheath : they then appear under the fold of Douglas, where they unite with the lym- phatics which arise from the aponeuroses which form the posterior wall of the sheath of the recti muscles. (3) The lymphatics of the aponeurotic edge of the ring are divided into anterior and posterior. The anterior lymphatics (vide Fig. 49,a) FIG 49. Lymphatics of the umbilical coverings (Cuneo and Alarcille). a. Lymphatic tributary of the axillary glands. b. Prae-aponeurotic network, c. Tributary trunk of the inguinal glands. d. Supero-external inguinal gland. e. Supero-internal inguinal gland. /. Infero-external inguinal gland. LYMPHATICS OF THE PELVIS AND ABDOMEN 151 arise from an extremely loose network, attached all round the umbilicus on the anterior surface of the aponeurotic sheath of Fic. 50. Lymphatics of the umbilicus (posterior view), (Cuneo and Marcille). a. Retro-Rponeurotic network. 6. Satellite trunk of the lumbar artery. o. Gland of the epigastric chain. d, c. Retro-crural internal gland. /. Retro-crural external gland. g Satellite trunks of deep epigastric artery. h. Satellite trunk of the umbilical vein. i. Supra- umbilical glandular nodules. /. The infra-umbilical gland. the recti. They terminate in two systems of collecting trunks. Some (a) perforate the aponeurotic lamina of the umbilicus, gain the sheath of the recti, and unite with the lymphatics of the fibrous nucleus. Others (6) pass externally, perforate the internal and external oblique muscles and blend with homologous trunks coming from the posterior part of the aponeurosis. the termina- tion of which we will shortly indicate. The posterior lymphatics (Fig. 50) give rise to a peri-umbilical net- work placed on the posterior surface of the sheath of the recti. From this network run two systems of collecting trunks. Some (a) run externally, perforate the trans versalis, and run between this muscle and the internal oblique. Joining with homologous lymphatics coming from the anterior part of the aponeurosis they pass either to the external retro-crural gland (vide p. 130), following the course of the deep circumflex iliac artery, or accompanying a lumbar 152 SPECIAL STUDY OF THE LYMPHATICS artery, pass to a juxta-aortic gland. Others (b) run downwards, unite with the vessels coming from the fibrous nucleus, and keeping more or less in contact with the deep epigastric artery, terminate in the two external iliac glands which are placed immediately behind the crural ring, viz. the retro-crural external, and the retro-crural internal gland (/ and e), Fig. 5.0 (vide p. 139). In the lower third of the course of these lymphatic trunks, we meet with three to six glands, which are small but almost always present. These are the glands of the epigastric chain (the inferior epigastric glands of Gerota) which we have already had occasion to point out (vide pp. 134 and 135). In some cases, we may come across a little gland in the subperitoneal retro-umbilical cellular tissue. Gerota, who was the first to point out its existence, met with it twice in ten subjects. This gland is usually 2 to 4 centimetres from the umbilicus and is almost always placed a little laterally. It presents a certain interest from the pathological point of view, for it may be the point from which certain suppurative processes in this region may start, and which clinically corresponds to what has been described as the phlegmon of Heurtaux (Cuneo and Marcille). In the new-born infant Cuneo and Marcille have met with two small glands which are placed above the umbilicus in the subperitoneal cellular tissue (vide Fig. 50). These glands receive the lymphatics which come from the supra- umbilical portion of the network which is attached to the posterior portion of the sheath of the recti. Finally, we may add that the lymphatics of the umbilicus communicate with those of the bladder by means of networks which surround the urachus, and with those of the liver by very fine vessels which run the whole length of the umbilical artery. These communications enable us to under- stand the pathogeny of certain cases of secondary cancers of the umbilicus. BIBLIOGRAPHY. SAPPEY, loc. cit., p. 50. GEROTA. Ueber die Lymph- gefasse unci die Lymphdriisen der Harnblase. Anat. Anz., 1896,' XII, p. 89. CUXKO et MARCILLE. Note sur les lymphatiques de 1'ombilic. Soc. anat., nov. 1901. II. LYMPHATICS OF THE EXTERNAL GENITAL ORGANS. We will study (a) the lymphatics of the external genital organs in the male and (b) in the female. As we shall see, these vessels have an arrangement which is identical in the two sexes. (a) In the Male. LYMPHATICS OF THE SCROTUM. The lymphatics of the scrotum take origin from an extremely rich network ; so that the injection of these vessels is extremely easy, at least in the infant. In the adult, the fragility of the meshes of the network renders their injection LYMPHATICS OF THE PELVIS AND ABDOMEN 153 a more delicate operation, especially when mercury is used. This network covers the entire surface of the scrotum, but is especially lense about the raphe, and it is there that it can be most easily injected. It is near the raphe, too, that the large collecting trunks appear which, later on in their course, collect the small branches coming from the lateral parts of the scrotal network. These trunks number from ten to fifteen on each side. They may be dis- tinguished as superior and inferior. 10 FIG. 51. Glands of the inguinal region ; afferent and efferent vessels. (From Sappey's Atlas.) 1, 1. The two lowest glands of the inguinal region are remarkable for their size. 2. Infero-external gland. 3, 3. Internal inguinal glands, in which terminate the vessels of the scrotum, perineum, anal region, and the supero-internal portion of the integuments of the thigh. 4. Superior and internal inguinal gland ; it receives vessels coming from the urethral canal, from the surface of the glans, and from the integuments of the penis. 5, 5. Supero- internal and external inguinal glands ; in these glands, which are three or four in number, terminate the vessels coming from the sub-umbilical portion of the abdomen. 6, 6. Lym- phatic vessels from the antero-internal portion of the thigh. 7, 7. Vessels from the external portion of the thigh. 8, 8. Vessels from the gluteal region. 9, 9. Vessels from the lumbar region. 10, 10, 10. Vessels from the sub-umbilical portion of the anterior wall of the abdomen. 11, 11. Lymphatic vessels of the scrotum. 12. Lymphatic vessels of the pre- puce. 13, 13. Lymphatic vessels of the integuments of the penis. 14. Lymphatic trunk which surrounds the corona of the glans. 15. Median trunk, which is continuous with the preceding. 10. Umbilicus. 154 SPECIAL STUDY OF THE LYMPHATICS (a) The superior trunks (median trunks of Sappey), arise from that portion of the scrotal raphe which is immediately continuous with the raphe of the penis. They run at first vertically upwards, then having reached the root of the penis, curve sharply outwards. They then run parallel to the collecting trunks of the penis, cross the spermatic cord and terminate in the supero-internal group of super- ficial inguinal glands. (On the nomenclature of these glands, vide pp. 114 and 115). (I) The inferior trunks (lateral trunks of Sappey) arise from the raphe, below and behind the preceding. They run upwards and outwards towards the lateral parts of the scrotum ; they then follow the cruro-scrotal groove, which they quickly leave, and then pass directly outwards and terminate in the infero-external and in- fero-internal glandular groups. The collecting trunks of the scrotal network frequently anasto- mose with those from the penis, and perineum, and with the trunks coming from the supero-internal part of the, skin of the thigh. LYMPHATICS OF THE PENIS. The lymphatics of the penis comprise : (1) the lymphatics of the cutaneous coverings of the penis ; (2) the lymphatics of the glans ; (3) the lymphatics of the penile portion of the urethra ; (4) the lymphatics of the erectile structures. Our knowledge of the latter is still imperfect : moreover their collecting trunks are in all probability blended with those of the penile urethra, which we will study later on with the lymphatics of the other portions of the urethra (vide p. 175). We shall now only have to consider the cutaneous lymphatics and the lymphatics of the glans. (1) THE CUTANEOUS Li'MPHATics. The cutaneous lymphatics may be divided into two groups ; the lymphatics of the sheath of the penis and the lymphatics of the prepuce. (a) The lymphatics of the sheath of the penis are fairly numerous, but difficult to inject. They form a network with fairly regular meshes which is continuous in front with the network of the prepuce. At the raphe, the meshes become finer and closer. In this situation also the collecting trunks appear. These are four or five in number and the more anterior their origin the longer they are. They turn round the lateral surfaces of the penis, and then run on its dorsal surface; they then pass directly backwards to the root of the organ, where they make a sharp bend, and turn outwards towards the inguinal glands. LYMPHATICS OF THE PELVIS AND ABDOMEN 155 (b) The lymphatics of the prepuce arise from a very fine network which follows in its plicature the skin of the praeputial fold. The lymphatics of the superficial portion are more developed than those of its deep or reflected portion. In the balanitic portion of the prepuce, the network is continuous with the lymphatic network of the glans. The small trunks of this network end either in a single median collecting trunk, or in two juxta-median, or in multiple collect- ing trunks. Contrary to Sappey's views, Brulms regards this latter arrangement as the rule. In any case whatever their number, these vessels run in the middle of the dorsum of the penis by the side of the superficial dorsal vein, and anastomose with each other by branches which are more or less developed in different subjects. These vessels are however especially remarkable for their sinuosities, on which point Gerard Marchant has laid stress : they are caused by alterations in size of the penis. When several trunks are present, they divide into two groups at .the root of the organ ; when only one trunk exists, it usually divides into two secondary branches, which are frequently unequal in size. This trunk may even be seen to remain undivided and end in the inguinal glands of one side. Whether their point of exit be through the sheath of the penis or the prepuce, the cutaneous lymphatics pass towards the inguinal glands, running immediately underneath the integument. For the greater part, they terminate in the supero-internal group, but they may also end in the other glandular groups of this region (vide p. 119 and Fig. 51). In the case of a neoplasm of the integuments of the penis, we must regard all the superficial inguinal glands as liable to become infected. Further, by reason of the inter-crossing or the bifurcation of the collecting trunks, there is a strong probability that a lesion which is quite clearly unilateral will affect the glands of the opposite side. (2) LYMPHATICS OF THE CLANS. The lymphatics of the glans arise from a network with very fine meshes, which has been perfectly described by Sappey. This network is partly continuous with the network of the prepuce, and that of the balanitic portion of the urethra. From this network run a series of small collecting trunks. "The direction of the latter is remarkable: all run from before backwards towards the fraenum of the penis, which invariably represents their centre of convergence. On the 156 SPECIAL STUDY OF THE LYMPHATICS right and left of the fraenum they receive two or three trunks coming from the mucuous membrane of the urethra, they then FIG. 52. Lymphatics of the glans in the new-born infant (Cuneo and Marcille). a. Lateral aortic gland. b. Gland of the promontory. c. External iliac gland (internal chain). d. Retro-crural internal gland. e. Glandular nodule placed at the entrance of the inguinal canal. /. Praesymphysian glandular nodule. g. Collecting trunks of the network of the mucous membrane of the glans. h. Network of the mucous membrane cover- ing the glans. i. Gland of the promontory. /. External iliac gland (middle chain). k. Retro-crural external gland. /. Crural collecting trunks of the glans. bend backwards, and arrange themselves behind the corona of the glans round which they turn ; they then mount upwards as far as its median part, where those of one side unite with those of the opposite side " (Sappey). According to Sappey, they blend into a single trunk which ends in the superficial inguinal glands. The researches of Kiittner, Bruhns, Cuneo and Marcille have not confirmed the description given by Sappey. According to these authors, the lymphatics of the glans end in multiple collecting trunks, which vary from two to four in number. These vessels run parallel to the deep dorsal vein of the penis ; and so are sub-aponeurotic. They thus arrive at the root of the penis, in front of the symphysis, where they effect some anasto- moses and thus form a sort of praesymphysian plexus with very LYMPHATICS OF THE PELVIS AND ABDOMEN 157 large meshes. At this spot may be found some small glands which belong to the group of interrupting glandular nodules (vide p. 86) and which we will term praesymphysial glandular nodules (vide Fig. 52). From this praesymphysial plexus run several collecting trunks which follow a different course ; some run towards the crural canal (the crural route), others pass into the inguinal canal (the inguinal route). (a) The crural trunks, three to four in number, run trans- versely outwards, passing beneath the femoral aponeurosis, in front of the pectineus. At first grouped in a single bundle, they soon diverge in the vertical direction. The lowest of them terminates in a deep inguinal gland, which is lodged in the crural canal, internal to the femoral vein. The suprajacent trunk terminates in the gland of Cloquet ; the third crosses the crural canal, enters the pelvis, and ends in the internal retro-crural gland (vide TOPOGRAPHY OF THE PELVIC GLANDS, p. 129). In short, they all end in a series of glands vertically placed one above the other, and ranged along the femoral vein, and the external iliac vein. This route is therefore partly femoral, and partly pelvic. (b) The inguinal route usually only comprises a single trunk, which passes into the inguinal canal, and which runs underneath the sper- matic cord, which must be raised to see it. It may present in its course a small interrupting glandular nodule, which is usually placed at the entrance of the inguinal canal. This trunk terminates in the external retro-crural gland. Bruhns maintains that some of the collecting trunks which come from the glans end in the superficial inguinal glands. We only admit this termination, as an anomaly, and are of opinion that, when by puncturing, the gians, the superficial glands become injected, it is because the injection has penetrated into the plexus of the prepuce. Kiittner has seen a trunk embrace the large vessels, ascend beneath them to a gland placed on the spot where the ureter enters the pelvic cavity. This is a very rare arrangement. Kiittner also described a trunk which, coming from the praesymphysian network, passed between the recti, and terminated in a hypogastric gland (?) and in a gland placed a little internal to the epigastric vessels. We think this too is an anomaly. We should a priori expect to find the collecting trunks closely accompanying the dorsal artery of the penis, and then following the internal pudic. These vessels do exist, but do not come from the glaris. According toCuneo and Marcille, they come exclusively from the urethra. BIBLIOGRAPHY. -MASCAGNI, loc. cit., p. 38 et tab. XI. SAFPEY, loc. cit., p. 51 et pi. VII. KCTTNEJK. Zur Verbreitung und Prognose des Peniscar- 158 SPECIAL STUDY OF THE LYMPHATICS cinoms, Arch. /. klin. Chir., 1899, LIX, 1, p. 180. BRUHXS. Ueber die Lymphgefasse der ausseren mannlichen Geiiitalieii und die Zuflusse der Leistendriisen. Arch. /. Anat. u. Phys., An. Abth., 1900, p. 281. CUXEO et MARCILLE. Note sur les lymphatiques du gland. Bull. Soc. anat.. decembre 1901. (b) In the Female. LYMPHATICS OF THE VULVA. The lymphatics of the vulva arise from a network the extremely close meshes of which are superposed in several planes. " This network covers the fourchette, the meatus urinarius, the vestibule, the clitoris, the labia minora, and the internal surface of the labia majora ; it is so loose and FIG. 53. Lymphatics of the clitoris (Cuneo and Marcille). a. Right juxta-aortic gland. 6. Gland of Cloquet. r. Deep inguinal gland. -d. Common iliac gland (external gland). e. External iliac gland (external chain). g. Lymphatic vessel of the clitoris taking an inguinal course. close throughout that when it has been well injected, it presents at first sight merely an ashy grey appearance. To distinguish the in- numerable silvery filaments of which it is composed, we must use a magnifying glass. On the external surface of the labia majora, the network, composed of smaller and larger branches, becomes suffi- ciently distinct to be recognized by the naked eye." (Sappey.) From the periphery of this network of origin run the collecting trunks. The direction of these trunks varies according to their points of origin. Those which come from the anterior third of the vulva, run directly upwards, and forwards towards the rnons Veneris ; there, they turn sharply and run transversely towards LYMPHATICS OF THE PELVIS AND ABDOMEN 159 the superficial inguinal glands. The trunks which come from the posterior two-thirds are directed upwards and outwards, and directly reach their terminal glands. The majority of the lymphatics of the vulva terminate in the glands of the supero-internal group. Some of them may end in the infero-internal group. It is even possible, though much more rare, to see some of these vessels reach a gland belonging to one of the two external groups. As has been seen, the vulvar lymphatics are far from being confined to a perfectly definite glandular group. When injecting one half of the vulva, the mass may frequent- ly be seen to reach the glands of the opposite side. The injection of these glands may take place by a double process. Sometimes it is effected on account of the continuity of the network of origin of the two sides of the vulva in the middle line ; at others it is due to the fact that some of the collecting trunks cross the middle line, and end in the inguinal region of the opposite side. In all cases, when dealing with an epithelioma of the vulva, the inguinal glands of both sides should be regarded as liable to infection. LYMPHATICS OF THE CLITORIS. The lymphatics of the clitoris deserve special mention. In fact, though the lymphatics of the prepuce of the clitoris pass into the superficial inguinal glands, like the other lymphatics of the vulva, this is not. the case with the lymphatics of the glans of the clitoris. These latter, which were passed over in silence by the older writers, have recently been studied by Marcille and one of the present writers. As their general arrangement is identical with that of the lym- phatics of the glans in the male, we will content ourselves by indicating it briefly. As in the male, the network of origin gives rise to several collecting trunks which run on the dorsal surface of the clitoris, and reach the front of the symphysis ; they anastomose at this spot, and form a praesymphysial network in which some small glands may be seen (vide Fig. 53). From this plexus run two sets of collect- ing' trunks (a). One of these vessels runs in the inguinal canal, and ends in the external retro-crural gland. This vessel is usually placed beneath the round ligament, and may show in its course a small interrupting glandular nodule. (6.) Other trunks run towards the crural canal and end in a deep inguinal gland, in the gland of Cloquet, and in the internal retro-crural gland. BIBLTOGRAPHY.-SAPPEY, loc. cit., p. 54 et pi. VIII, Fig. 1, 2, S.-BBUHXS. 160 SPECIAL STUDY OF THE LYMPHATICS Ueber die Lymphgefasse cler weibl. Genitalien, etc. Arch. /. Anat. u. Pliys., Ariat. Abth., 1898, p. 59. CUNEO et MARCILLE. Note sur les lymphatiques du clitoris. Bull. Soc. anat., novembre 1901. III. LYMPHATICS OF THE INTERNAL GENITAL ORGANS. These we will study first in the male and then in the female. (a.) In the Male. LYMPHATICS OF THE TESTICLE. The lymphatics of the testicle, whose mode of origin we will study further on (vide Treatise of 11 - FIG. 54. Terminal glands of the lymphatics of the testicle in a new-born infant. 1. Left supra-renal capsule. Left spermatic vein. 3. Left juxta-aortio gland. 4. Inferior mesenteric artery. 5. Hype-gastric artery. 6. Rectum. 7. Right phrenic artery. 8. Superior mesenteric artery. 9. Right juxta-aortic gland. 10. Ureter. 1 1. Posterior, gland of the middle chain of the external iliac group. Human Anatomy. Poirer and Charpy, vol. v. p. 269), unite with the lymphatics of the epididymis, and the visceral layer of the tunica vaginalis, and run towards the lumbar region along the spermatic cord. LYMPHATICS OF THE PELVIS AND ABDOMEN 161 They are usually more superficial than the blood-vessels with which they are in immediate contact. In our preparations they varied from four to eight in number. Owing to the division of some of these vessels, it has appeared to me that this number, far from becoming reduced during their course, on the contrary increases. Having arrived in the lumbar region these trunks leave the sper- matic vessels and run towards their terminal glands, either describ- ing a fairly regular curve, or sharply bending at a right or even on acute angle. The trunks coming from the right testicle terminate in the right juxta-aortic glands. The lowest of these glands situated immedi- ately above the bifurcation of the inferior vena cava, alwa}^s receives one or two afferent trunks. In a third of the cases one or two of these lymphatics empty themselves into one of the prae-aortic glands. The trunks of the left side end in the three or four glands of the left juxta-aortic group, which are arranged in rows below the renal vessels, but here again, we may sometimes see that some lymphatics are not arrested in the glands of this group, but directly reach the prae-aortic glands. Most remarks that the glands which receive the lymphatics of the left testicle, are placed at a somewhat higher level than those which receive the trunks coming from the right testicle. In a third of the cases, however, these two glandular groups are clearly placed at the same level. Zeissl and Horowitz have described as constant, a vessel which they ob- served on puncturing the internal surface of the testicle: this vessel, at first a satellite of the vas deferens, leaves this duct and terminates in one of the elands of the external iliac chain. This vessel has not been noticed by the older writers. Most was unable to inject it in man, and was only successful in showing it in the rat and dog. One of the present writers has injected it in several subjects, and has seen it end in a gland placed on the external iliac vein immediately in front of the spot where this vein is crossed by the ureter. In all probability then, the arrangement is a constant one, but we must agree with Most that this vessel is somewhat difficult to inject. In a full-term foetus, one of the authors noted the existence of three little glands placed over the lymphatics of the testicle, in their course through the iliac fossa. This arrangement must be somewhat rare, seeing that it has not been, mentioned at all in anatomical literature, and that out of eighteen subjects examined by us we have only come across it once. BIBLIOGRAPHY. Pour les indications concernant 1'origine des vaisseaux, voy. t. V. p. 270 et REGAUD, Th. dp, Lyon, 1897. GERSTER. Ueber die Lyraphagefasse des Hodens. Zeitsch. f. Anat. u. Entwickelung., t. II, 1876. ZEISSL i HOROWITZ, Wiener klinische Wochenschr., 1890, p. 388 et Wiener 162 SPECIAL STUDY OF THE LYMPHATICS medicinische Presse, XXXVIII, p. 761. MOST. Ueber maligne Hodentumoren u. ihre Metastasen. Virchow's Arch., 1898, CLIV, p. 138. MOST. Ueber die Lymphgefasse n. Lymphdriisen des Hodens. Arch. /. Anat. n. Phys., Anat. Abth., 1899, p. 113, av. 1 fig. CUNEO. Note sur les lymphatiquea du testicule, Bull. Soc. anat., fevrier 1901. LYMPHATICS OF THE VAS DEFERENS. Though it may be taken for granted that the lymphatics of the vas deferens arise from two networks, one of which is in connection with the mucous, and the other with the muscular coat ; up to the present time no one has succeeded in injecting the mucous network. Moreover, the lymphatics of the vas deferens are remarkably thin, especially in its middle part (Sappey). The collecting trunks pass to the external retro-crural gland and to the posterior gland of the middle chain of the external iliac glands. LYMPHATICS OF THE VESICULAE SEMINALES. The lymphatics of the vesiculae seminales are much easier to inject, and much more is known about them. They arise from two networks, one mucous, and the other muscular. The trunks coming from this network anastomose one with another on the surface of the vesiculae, and thus constitute a third network, from which the collecting trunks originate. Though our researches have not been sufficiently numerous to enable us to determine with certainty the course of these collecting trunks, we would willingly regard as normal the existence of two vessels, one of which goes to the posterior gland of the middle chain of the external iliac glands, while the other terminates in a gland of the hypogastric group. The lymphatics of the vesiculae seminales anastomose to a large extent with those of the bladder and especially with those of the prostate. (b) In the Female. LYMPHATICS OF THE OVARY. The lymphatics of the ovary, whose mode of origin we shall study later on (vide vol. v. p. 370 '), are remarkable for their numbers. In well-injected preparations, they form, even at the hilum, a plexus of the greatest richness, the close-set meshes of which entirely prevent the subjacent venous plexus from being seen. Little by little the plexus diminishes in size : it finally resolves itself into four, five, or six lymphatic trunks, which immediately take an upward course ; these trunks, which accompany the ovarian vessels, run with them under the peritoneum, pass in front of the common iliac vessels, then cross the ureter, and terminate in the lumbo-aortic glands. Our injections with mercury 1 Treatise of Human Anatomy, Poirierand Charpy. LYMPHATICS OF THE PELVIS AND ABDOMEN 163 and with Gerota's solution have shown us that the arrangement of their terminal glands is precisely the same as that of the glands which receive the lymphatics of the testicle, that is to say, they terminate in the lateral-aortic glands of the corresponding side. In this ascending course, the lymphatics of the ovary unite with the lymphatics com- ing from the fundus of the uterus and from the Fallopian tube ; but at first they are simply placed next to these vessels, and it is only when they reach the level of the 5th lumbar vertebra, that they commence to exchange anastomoses with them (Poirier). In the course of the ovarian lym- phatics, small interrupt- ing glandular nodules may be found (Stahr, Marcille). From the ovary also a vessel may be seen, which runs downwards and slightly outwards, into the upper part of the broad ligament and ends in one of the glands of the middle chain of the internal iliac group (Marcille). In this connection we may recollect that Zeissl and Horowitz, and subsequently one of the authors, have seen one of the lymphatics of the testicle end in this same gland. LYMPHATICS OF THE FALLOPIAN TUBE. Arising from the three coats of this organ (vide vol. v. p. 393 *) the lymphatics of the tube unite with those of the uterus and ovary, and share with them their mode of termination in the two lateral chains of the abdomino-aortic group. LYMPHATICS OF THE UTERUS. As we shall see later on (vol. v. p. 481 1 ), the lymphatics of the uterus arise from three capillary 1 Treatise of Human Anatomy, Poirier and Charpy. -Scheme of the lymphatics of the uterus (Cuneo and Marcille). a. Lumbar pedicle of the body. 6. External iliac gland. c. External iliac pedicle of the body. d. Pedicle of the round ligament. e. Hypogasuic pedicle of the neck. /. Pedicle of the promontory. g. Gland of the promontory. h. Lateral sacral gland. i. Hypogastric gland. j. External iliac pedicle of the neck. 164 SPECIAL STUDY OF THE LYMPHATICS networks, viz. : a mucous, a muscular, and a peritoneal network. The trunks originating from these three networks of origin all assemble on the surface of the uterine muscle in the sub- peritoneal cellular tissue, where they form by their anastomosis, a fourth and final network from which the collecting trunks start. Though the networks of origin of the cervix and of the body are Fig. 50. Lymphatics of the uterus (Cuneo and Marcille). o. Lumbar pedicle of the body. b and c. External iliac pedicle of the neck. d. External iliac pedicle of the body. e. Juxta-cervical lymphatic knot. /. Gland of the promontory. g. Pedicle of the promontory of the neck. /<. Intrapelvicgluteal gland. {. Lateral sacral glands. /. Hypogastric pedicle of the neck. k. Lateral sacral pedicle of the neck. continuous with each other without any line of demarcation, we will study the collecting trunks of these two portions of the uterus quite separately. (1) COLLECTING TRUNKS OF THE NECK OF THE UTERUS. The cervical collecting trunks converge towards the lateral portions of the body of the uterus. They vary in number from five to eight, and not from LYMPHATICS OF THE PELVIS AND ABDOMEN 165 two to four as the older writers stated. After leaving the cervix, these trunks, which are twisted and dilated, form a large lymphatic knot, which was well described by one of the present writers in 1890, and which we must avoid mistaking for a gland. This juxta-cervical knot, which is always well developed in the pregnant female, is, on the contrary, often absent in the new-born. The cervical collecting trunks may be subdivided into three ;: pedicles." (a) A primary pedicle (external iliac pedicle, transverse or prae-ureteric pedicle) comprises two to three trunks which run at first directly outwards, passing in front of and above the ureter. Excep- tionally, one of them may pass behind and beneath this duct. At first satellites of the uterine artery, they soon leave this vessel. They then run up the lateral Avail of the pelvic cavity, passing internal to the hypogastric artery, which they are obliged to cross in the foetus. They terminate in the middle and superior glands of the middle chain of the external iliac group (vide Fig. 56). At the level where these vessels cross the ureter, we may find as an abnormality, an interrupting glandular nodule, which, when of fair size, constitutes a true juxta-cervical gland. Juxta-cervical gland. The existence of this gland has been much dis- cussed. Cruikshank, Mascagni, and nearer our own time, Henle, Luschka, and Cruveilhier do not mention it. M. Lucas Championniere was the first to notice the presence of a gland in the neighbourhood of the cervix of the uterus. " I have often seen, and have had a drawing made of a gland situated at the side and back of the cervix of the uterus." In his work on the lymphatic system, Sappey denies the existence of this gland, yet in one of his plates (plate xlvi., Fig. 9) he represents a gland over the cervical col- lecting trunks, and situated nearly midway between the cervix and pelvic wall. One of the authors of this work has searched for this gland in more than 300 subjects without succeeding in discovering it ; Bruhns on the contrary, declares he has met with it twice in eleven subjects, and more recently, Marcille and one of the present writers have found it five times in thirty subjects injected by Gerota's method. We shall shortly see that we may meet with analogous glandular nodules in the course of other trunks coming from the cervix of the uterus. Therefore one or several juxta-cervical glandular nodules may all exist. In normal subjects these nodules are always small, and exhibit the characteristics belonging to the Schaltdriise. In mercury injected preparations, they easily escape detection ; injection by Gerota's method shows them best. If any one of these nodules hypertrophies as the result of a pathological process, the operator will find a* true gland lying by the side of the cervix of the uterus. This fact has been noticed several times during the course of an hysterectomy (Reynier). (b) A second pedicle (hypogastric pedicle) arises from the same level as the preceding, but passes behind and below the ureter. It is formed by one or two vessels, which are directed obliquely 166 SPECIAL STUDY OF THE LYMPHATICS upwards, backwards, and outwards, and terminate in a gland of the hypogastric group. This gland is usually placed on the an- terior terminal trunk of the hypogastric artery, at the level of origin of the uterine or vaginal arteries. (c.) A third pedicle (pedicle of the promontory and lateral sacral ped- icle) comprises two to three collecting trunks, which spring from the posterior surface of the cervix, and at first descend upon the vagina, then run backwards, crossing the lateral surfaces of the rectum, and passing within the sacro-rectal or utero-sacral ligaments ; they then mount upwards into the concavity of the sacrum. The external, the shorter, are arrested in the lateral sacral glands ; the internal, the longer, pass to the glands of the promontory. As has been seen in Fig. 56, and especially in Fig. 55, all the lymphatics coming from the neck describe a series of con- centric curves, arranged in different planes. The external iliac pedicle, the shortest, is almost transverse ; the hypogastric pedicle which is longer, lies in an oblique plane which points backward, and outwards ; the pedicles of the lateral sacral and promontory, still longer, are entirely sagittal. In some cases, the lymphatics which end in the lateral sacral glands do not pursue sucli a long course as that we have just indicated. They are arrested as they pass under the peritoneum, either at the level of the free border of the utero-sacral ligaments or external to them. A lymphatic of the cervix may pass through the broad ligament obliquely and join the vessels which constitute the lumbar pedicle of the body of the uterus (this was found three times in thirty subjects, Cuneo and Marcille). This trunk must not be confounded with the vertical juxta-uterine anastomosis which we shall describe further on. (2) COLLECTING TRUNKS OF THE BODY OF THE UTERUS. The collecting trunks of the body of the uterus may be divided into three groups, viz. : a principal and two accessory groups. (a). The principal pedicle comprises four to five trunks, which appear beneath the cornu of the uterus. These vessels at first follow the terminal segment of the uterine artery, then pass beneath the ovary, where they are joined by the vessels coming from this gland. They then run in the suspensory ligament of the ovary with the ovarian vessels, and ascend towards the lumbar region, running round the blood vessels. Like the latter, they cross the ureter on its anterior surface. Having arrived at a spot slightly below the hilum of the kidney, they curve sharply, and " descend in showers " upon the juxta-aortic glands of the corresponding side. Some of them may, however, end in the prae-aortic group. LYMPHATICS OF THE PELVIS AND ABDOMEN 167 \Ve may find in the course of these vessels, one or several small interrupting glandular nodules (Stahr, Marcille). They are comparable to those de- scribed by one of the authors as lying in the course of the lymphatics of the testicle. (b) The two accessor}/ pedicles pass, one, to the external iliac glands, the other, to the inguinal glands. Vena cava .__ Eight kidney Eight venal vein __--- Right spermatic artery Superior lumbar _ gland Inferior lumbar gland Lymphatics from body of uterus Anterior crural nerve Peritoneum Lymphatics in utero-sacral lignt. Lymphatics of cervix Lymphfitic-s of round lignt. Aorta Left kidney Left renal vein Reno-asygo-lumb'ir vein Spermatic artery i'reter Inferior metenteric artery Middle lumbar gland Middle sacral artery Ovarian lymphatics Pelvic colon Lymphatics of Fal- lopian tube i'nl'f>r>ian tube Uteru$ Bladder Fig. 57. General view showing the lymphatics of the internal genital organs of the female (Poirier). The primary, which was observed by Sappey (loc. cit. p. 129 and plate xlvi. Fig. 9 and 10), and by Bruhns, is formed by one to two trunks, which take origin a little below the cornu of the uterus. They run directly outwards, and end in the glands of the - . . 168 SPECIAL STUDY OF THE LYMPHATICS middle chain of the external iliac group. This chain therefore receives the lymphatics of the neck and body at the same time. The second accessory pedicle as a rule only comprises a single trunk, which terminates in a superficial inguinal gland of the supero-internal group. These lymphatics, which were observed by Mascagni (loc. cit., p. 44), are difficult to inject. Whether mercury or Gerota's solu- tion is used, it is rarely that we can trace them to their terminal glands ; most frequently the injection is arrested at the internal orifice of the inguinal canal. The lymphatics of the neck and body are not only united by Lymphatics from the body pass ing to lumbar glands. Lymphatics of body and fiindus. 1 Lymphatics from the body passing to lumbar ijlunds. Lymi'hatic ring . Lymphatics of cervix. Fig. f>8. Lymphatic vessels of the uterus (Poiror). the continuity of their networks of origin, but also by a long ver- tical juxta-uterine anastomosis (vide Fig. 58). One of the present writers some while ago described this anastomosis, and Bruhns is quite wrong in denying its existence. In a fresh series of researches we have again almost invariably found it (Cuneo and Marcille). Uterine Lymphatics and the Obturator Gland. There has been much dis- cussion as to whether the lymphatics coming from the uterus end in the gland called " obturator." We have already explained our ideas on this gland (vido p. 132). We have seen that usually no gland exists at the actual level of the pelvic orifice of the obturator foramen, and that the small gland which may be found abnormally at this spot is simply an interrupting nodule placed over the lymphatics, the satellites of the obturator vessels. The gland to which authors alluded, when they spoke of the obturator gland does not at all correspond to this glandular nodule, but clearly does so to the middle gland of the internal chain of the external iliac group, a gland which is placed behind and below the obturator foramen, and at some distance from LYMPHATICS OF THE PELVIS AND ABDOMEN 169 the latter. Does this gland receive any lymphatics coming from the uterus ? Ouveilhier and Lucas-Championniere are of this opinion, and on this hypothe- sis. A. Guerin rested his theory of sub-pubic obturator aderio-phlegmon. Dur- ing the discussion at the Academy of Medicine originated by Guerin' s communication, Sappey felt bound to contradict the statement that this gland receive any lymphatic tributaries from the uterus. Later researches by Poirier, Bruhns, Peiser, Cun6o, and Marcille, etc., have confirmed Sappey' s opinion. The fact that this gland may perhaps be affected during the progress of cancer of the uterus (Malartic and Guillot) is no proof at all that it directly receives any uterine lymphatics. This inva- j-i'jn is in fact easily explained by the numerous anastomoses which this gland effects with the first glandular relay of uterine lymphatics. Technique. We will study in turn the injection of (a) the mucous mem- brane. (6) the muscle, (c) the uterine peritoneum. (a) Lymphatics of the Mucous Membrane. To see the lymphatics of the mucous membrane, a puncture must be made in the region of the cervix uteri. The procedure is as follows : The anterior wall of the cervix is incised, and after the two cut edges have been drawn well aside, the point of the tube is directed against the median column of the posterior wall. When the opera- tion is successful, the lymphatic network of the mucous membrane instant- ly appears over the entire length of the mucous membrane of the cervix , and we see it becoming continuous below with that of the mucous membrane of the external os. While injecting the lymphatics of the mucous membrane of the cervix by this method, it often happens that we distend those of the mucous membrane of the body. On the other hand, the direct puncture of this mucous membrane gives negative, or onlj* very incomplete results; though only three or four meshes have been in- jected, ruptures are produced at many points in the lymphatic network of this extremely friable mucous membrane. (b) The Lymphatics of the Muscular Coat. The injection of the lymphatics of the muscular coat is very easy. If the uterus has previously been placed for an hour in water at 40 so as to render its walls normally supple, it is very rarely that we fail after the first puncture to inject all or a part of the muscular lymphatic network. Moreover, as one of the present authors long since observed, of all selected spots it is here especially that punctures yield particularly good results ; in this respect, the cervix and the uterine cornua should be placed in the first rank. When mercury is used, the first puncture must be made under a pressure of from 20 to 30 centimetres. When once the mercury has appeared in the collecting trunks, the pressure must be considerably diminished ; unless this precaution is taken, the mercury bursts the vessels at their exit from the organ, and it is impossible to follow them to their terminal glands. (c) Lymphatics of the Serous Coat. The injection of these vessels is a much more delicate process. We have succeeded in filling them by very super- ficially puncturing the peritoneum which covers the uterus, and then intro- ducing the fine point of a canula, in such a manner that it penetrates the subendothelial layer, without reaching the cellular tissue which unites the peritoneum to the uterus. This very fine network is easily distinguished from the subserous network, which represents the network of origin of the uterine collecting trunks. We may remind ourselves that it was Mierzejewski, and subsequently one of the present authors, who placed the existence of this peritoneal network beyond a doubt. L 170 SPECIAL STUDY OF THE LYMPHATICS To inject the collecting trunks of the uterus, it suffices to press the injected material into the uterine muscle. The uterus must be injected in situ, especiallj' if Gerota's method is used. After the injected portions have by this method been fixed by formal, or Kaiserling's liquid, a section of one half of the pelvis may be made, which much facilitates the dissection of the uterine collecting trunks. BIBLIOGRAPHY. On account of their importance from a pathological point of view, the uterine lymphatics have been made the subject of numerous researches. Previously carried out with the object of determining, if possible, the pathogeny and the seat of peri-uterine suppurations, these researches have more recently been undertaken with the view of settling which glands are affected in cancer of the uterus. We will here confine ourselves to indicating the records of research dealing with the microscopic anatomy of the uterine lymphatics ; and for works on the histology of these vessels will refer the reader to the article Uterus (vide 1 vol. v, p. 481). MASCAGNI, loc. cit., p. 44 et pi. XIV. SAPPEY, loc. cit., pi. XLVI, Fig. 9 et 10. LUCAS-CHAMPIONNIERE. Les lymphatiques uterins et la lymphangite uterine. Th. Paris, 1870. FRIDOLIX. Des vaisseaux lymphatiques de 1' uterus gravide. Militdrdrtz Zeitschr., Petersbourg, 1872. LEOPOLD. Lymphgefasse des Uterus, Arch. /. Gyndkolocjie, 1789, VI, p. 1. FIOUPE. Lymphatiques uterins et parallele entre la lymphangite et la phlebite uterines. Th. Paris, 1876. MIERZEJEWSKI. Recherches sur les lymphatiques de la couclie sous-sereuse de 1' uterus. J. de V Anatomic, 1879, p. 201. CAXTIX. Th. Paris, 18S9. WALLTCH. Recherches sur les vaisseaux lymphatiques sous-sereux de 1'uterus gravide et 11011 gravide. Th. Paris, 1891. POIRIER. Lymphatiques des organes genitaux de la femme. Progres medical, 1890, II, p. 491. AIouAV. Kemarques sur les vaisseaux lymphatiques des organes genitaux de la femme et leurs anastomoses avec ceux tlu rectum, Comptes rendits Soc. BioL, 1894, 11 33, p. 812. BRUHNS. Ueber die Lymphgefasse der weiblichen Genitalien nebst einigeii Bermerkungen liber die Topographic der Leistendriisen. Arch. /. Anat. ^t. Phys., Anat. Abth., 1898, p. 57. PEISER. Zeitschr. /. Gcburt. 11. Gyndk., 1898, t. XXXIX, 2e fasc., p. 259. MALARTIC ET GUILLOT. Cancer uterin avec ganglion sous-pubien. Bull. Soc. Anat.. 1900, p. 123. LYMPHATICS OF THE VAGINA. The lymphatics of the vagina arise from two networks, which are attached, one to the mucous mem- brane, the other to the muscular coat. The network of the mucous membrane is extremely rich, and its meshes so fine that the mercury which runs into them appears, at first sight, to form a continuous layer on the surface of the mucous membrane under the epithelium. The meshes of the network of the muscular coat are much larger and formed by coarser lymphatics. These two communicate with each other, and finally end in a third peri-vaginal network from which the collecting trunks emanate. All these collecting trunks pass to the glands of the pelvis. This exclusively pelvic termination of the vaginal lymphatics is parti- cularly evident in the infant, where the hymen clearly indicates the limits of the vulva and vagina. " If a puncture is made internal to 1 Treatise of Human Anatomy. Poirer and Charpy. LYMPHATICS OF THE PELVIS AND ABDOMEN 171 the hymeneal septum, one of the present writers affirmed some time ago that the mercury passes into the vessels which end in the pelvic glands ; if the external or vulvar surface of the septum is punctured, the vessels which pass to the inguinal glands are injected.' In the adult female, it is possible, if the inferior part of the vagina is punctured, for the injected mass to pass to the inguinal glands, but it only does so through the numerous anastomoses which unite Utero->:aginal lymphatics (superior group) Vaginal lymphatics \ map M I a<,mal lymphatic, ' -s jmSSS^i^g^S / ' " \ V // Vaginal lymphatics - -\ 1\ ^Ki^^'-'k'}'--'.'-'':-''^ '''.-. ,-'^ Vf // '/ (middle group) \ i'i N *M^^^PM^V/ / \ immimmi \ wWA?^.' 5 -. 1 ; affig rSs!wS ;--- ; -- $> ^: /;l Vaginal lymphatics / '^ (inferior group) f Lymphatics of valva 'J&f*fK &i~zK,*:'i ^5] -^^ $& Fig. 59. Lymphatic network of the mucous membrane of the vagina with their efferent trunks (Poirier). the vaginal to the vulvar network, and not by direct collecting trunks. But, though all the vaginal collecting trunks pass to the pelvic glands, we may, by taking their origin, course, and termination, as the basis of our scheme divide them into three groups : superior, middle and inferior. (a) The Superior Group. The superior lymphatics arise from the vaginal culs de sac, and are responsible for the lymphatic circu- lation of the upper third of the vagina. There are usually two trunks 172 SPECIAL STUDY OF THE LYMPHATICS on either side. One which springs from the anterior cul desac, runs upwards and outwards, passes in front of the ureter, then, embracing several of the trunks corning from the cervix, terminates with the latter in the middle, gland of the middle chain of the external iliac group. The other which comes from the posterior cul de sac also runs upwards and outwards and terminates either in the preceding gland, or in the posterior gland of the same chain (a and b, Fig. 60). Fig. 60. The lymphatics of the vagina (semi-diagrammatic) (Cunco and Marcille). a, b. External iliac glands (middle chain), c. Transverse external iliac pedicle, d. Gland of the promontory, e. Lateral sacral gland. /. Hypogastric gland, g. Hypogastric 'pedicle. h. Retro-vaginal glandular nodules. (b) The Middle Group. The lymphatics of this group come from the middle third of the vagina. They are satellites of the vaginal artery, and like this vessel, run obliquely upwards, backwards and outwards, and end in a gland of the hypogastric group, placed at the actual origin of the vaginal artery. These lymphatics and the glands in which they end are contained in the hypogastric space. LYMPHATICS OF THE PELVIS AND ABDOMEN 173 (c) The Inferior Group. The collecting trunks of this group appear at the lower .third of the recto- vaginal septum. At first descending, they then run outwards, then directly backwards, passing between the rectum and the sacro-recto-genital aponeurosis. They then pass upwards into the concavity of the sacrum, internal to the anterior sacral foramina, and terminate in the glands of the group of the promontory, or more rarely in a lateral sacral gland. Ovary Fallopian tube Fig. 01. Lymphatic vessels of the middle third of the vagina and the glands in which they end (Poirier). We may find some small interrupting glandular nodules lying 011 these different collectors, and in the case of the middle and inferior collectors they are constant. Some of them are even placed between the layers of the recto ^agmal septum. One of the authors pointed them out a long time ago, and our recent researches with Marcille's assistance have shown us that we may regard them as constant. To sum up, the lymphatics of the vagina run to the pelvic glands in three groups of collecting trunks : (a) A superior transverse group, ending in the middle chain of the external iliac glands ; (b) a middle group. which passes obliquely upwards and backwards, and terminates 174 SPECIAL STUDY OF THE LYMPHATICS in the hypogastric glands ; (c) an inferior sagittal group, which runs in front of the sacrum and ends in the glands of the promontory. ANASTOMOSES. The lymphatics of the vagina anastomose above, with those of the cervix uteri, and below, with those of the vulva, owing to the continuity of their networks of origin. Behind, they communicate with the lymphatics of the rectum ; Morau affirms that certain vessels which come from the anterior wall of the rectum join the collecting trunks which run in curves over the posterior surface of the vagina ; but to us, on the contrary, it seems that there is an absolute independence between the lymphatics of the vagina and those of the bladder. Technique. One of the present writers has laid clown the following rules for the injection by mercury of the lymphatics of the vagina. " The organ must remain in situ and its normal relations preserved as far as possible. To effect this, after detaching all the soft parts which form the anterior wall of the hypogastric and pubic regions, we make four saw cuts, passing through the horizontal rami of the pubes, the ascending rami of the ischium. and all the anterior part of the pelvic girdle : then seizing the bladder with forceps, this organ together with the urethra is carefully separated from the anterior vaginal wall. The anterior wall of the vagina and uterus are thus preserved intact in front. By the aid of scissors with rounded extremities, we next incise the anterior wall of the vagina in the middle line, keeping to the antero- posterior axis, from the bulb of the vagina to its insertion into the cervix. To avoid the escape of mercury through the numerous lymphatics opened by this incision, I think it advisable to place oil the lips of the incision a red hot stylet or the blade of a thermo-cautery. It is advantageous also, before pro- ceeding with the injection, to thoroughly cleanse the mucous membrane of tho vagina with a somewhat coarse cloth, to remove the layers of epithelium which cover it. Without this precaution we run the risk of blocking the mouth of the injection tube by the first puncture. Should this occur, another attempt must be made higher up, or at the side. The pressure necessary to effect a successful injection varies in different subjects : in infants, unly a very low pressure (8 to 10 centimetres of mercury) is required, but in the adult, it often has to be raised. To inject the network of the mucous membrane, the puncture ought to be made very superficially, but more deeply for that of the muscular coat. Sometimes, especially in the infant, a single puncture is sufficient to inject all the vagina ; but to make a complete injection, two or three punctures at different points are usually necessary : In these cases, it is necessary to seal up the apertures made by the preceding punctures by lightly cauterizing with the red hot end of a stylet. If one or several punctures produce 110 result, the experiment must be repeated until the mer- cury is seen to spread into and invade the lymphatic network wit); its well known rapidity ; the pressure must now be diminished and, if the sides of ilie vagina are carefully watched, one or two strands of mercury will be seen to shoot over its lateral portions and pass to the glands. During the injection, two or three trunks opened by the scalpel while detaching the bladder, will cause some leakage, but this can easily be arrested by some light cauteri- zations." The injection of the lymphatics of the vagina by Gerota's method may be effected by a similar process. BIBLIOGRAPHY. Vide UTERUS, pp. 166, 167 and 168. LYMPHATICS OF THE PELVIS AND ABDOMEN 175 4. LYMPHATICS OF THE URINARY PASSAGES. LYMPHATICS OF THE URETHRA. We will now study the lym- phatics of the urethra in the male and in the female. I. IN THE MALE. The lymphatics of the urethra arise from, a net- work attached to the mucous membrane of the urethra. The arrange- ment of this network of origin has been perfectly described by Sappey. " The lymphatic vessels of the mucous membrane of the urethra cover all its free surface, from the prostatic utricle to the meatus urinarius. Posteriorly, the network formed by these vessels and by the anastomoses which unite them, is continued on to theejaculatory Fig 02. Lymphatics of the penile and membranous portion of the urethra (Cuneo and Marcille). abed. External iliac glands, e. Penile proe-symphysian collecting trunk. /, g. Satellite trunk of internal pudic vessels. *. Collecting trunk coming from the anterior surface of the nrostate. t. Penile retro-symphysian collecting trunk. 176 SPECIAL STUDY OF THE LYMPHATICS ducts, and is thus continuous with that of the vesiculae seminales and the vasa deferentia. In front, it is continuous with the tortuous branchlets on the surface of the gland. This network has an excep- tional arrangement ; the larger and smaller branches which form it, follow the direction of the urethral Avails. By many transverse and oblique anastomoses, they unite very frequently and are grouped in parallel and unequal bundles, separated by longitudinal ridges." (Sappey). From this network emanate several collecting trunks which may be divided into four groups : 1. The only collecting trunks which Sappey mentions are those ivliich come from the mucous membrane covering the glans. They tra- verse the inferior wall of the urethra at the level of the f raenum, unite with the lymphatic trunks coming from the glans, and terminate in the same manner as those vessels (vide Fig. 52 and p. 157). 2. The collecting trunks which come from the remainder of the penile portion vary in number. They emerge on the inferior surface of the penis, turn round the lateral surfaces of the corpora cavernosa and unite with the trunks coming from the glandular portion. The majority run and terminate in the same way as the latter, but some take an entirely different course ; for instance, one of these vessels passes over the symphysis, runs between the two recti muscles, then turns directly to the left and terminates in the internal retro- crural gland. More rarely, it may be found to terminate in the middle gland of the internal chain of the external iliac glands. Kiittner was the first to note the presence of this vessel, but he was wrong in believing that it came from the mucous membrane of the glans. A second collector passes underneath the symphysis and unites with the vessels coming from the bulbar and membranous portions of the urethra. 3. The lymphatics of the bulbar and membranous portions end in the following three systems of collecting trunks : (a) One of these vessels makes its appearance on the upper sur- face of the bulb in the angle formed by the divergence of the two corpora cavernosa. It embraces either the transverse artery of the bulb, or the artery to the corpus cavernosum, it then becomes a satellite of the trunk of the internal pudic artery and terminates in the gland attached to the intra-pelvic portion of the trunk of this artery. (b) A second vessel runs towards the posterior surface of the sym- physis, and then behind the pubes to terminate in the internal retro- crural gland. LYMPHATICS OF THE PELVIS AND ABDOMEN 177 (c) A third trunk ascends on the anterior surface of the bladder, and unites with the trunks coming from the inferior segment of this surface, and terminates with the latter in the middle gland of the internal chain of the external iliac glands. 4. The lymphatics of the proslatic portion pass into the collecting trunks which emerge from the glandular parenchyma. The injection of the lymphatics of the urethra is a delicate process, and it is rather difficult to follow the somewhat complicated course of their collecting trunks. Sappey only mentions the vessels coming from the glandular portion of the urethra. More recently, Kiittner incidentally mentions several other collect- ing trunks. The description we have just given is founded on the researches carried out by one of the present writers with the assistance of Marcille. It makes no pretence at being final. We ought to remark that some of the collecting trunks whose course we have described have only been met with in certain subjects, in spite of the considerable number of specimens we have injected. It is therefore difficult to say whether this inconstancy is real, or whether it is caused by the difficulties of injecting these vessels. SAPPEY, loc. cit., p. 53 et pi. VII, Fig. 7. KCTTNER, Zur Verbreitung und Prognose des Penis-carcinoms. Arch. /. klin Chir., 1899, LIX, 1, p. 180. II. Ix THE FEMALE. The lymphatics of the urethra of the female have a precisely similar arrangement to that of the lymphatics of the membranous and prostatic portions in the male. They therefore end in the middle and internal chains of the external iliac glands, in the hypogastric glands, and in the glands of the promontory. LYMPHATICS OF THE PROSTATE. The lymphatics of the pros- tate arise by fine capillaries arranged in the form of a network round each glandular acinus. From these periacinous networks, run larger vessels which pass towards the periphery of the gland, and form at its surface a second network the periprostatic network, from which the collectors start. The latter, which are symmetrically arranged on each side of the gland may run in four different directions : 1. A primary trunk (a, Fig. 63) starts from the posterior surface of the prostate, and runs on to the bladder in the triangle between the vasa deferentia. It ascends as far as the middle part of the postero-superior surface of the bladder, where it curves sharply out- wards, crosses the hypogastric artery, and terminates in the middle gland of the middle chain of the external iliac group (vide p. 131). In its retro-vesical course, this trunk describes numerous curves ; it may pass through some small interrupting glandular nodules (Schaltdriisen), close to the spot where it crosses the hypogastric artery. This ascending channel frequently consists of two trunks which then terminate in the middle and superior glands of the middle chain. 178 SPECIAL STUDY OF THE LYMPHATICS 2. A second collector, arising like the preceding from the posterior surface of the prostate, accompanies the prostatic artery. Like the latter, it runs upwards, outwards and backwards, and terminates in one of the middle glands of the hypogastric group. In the neighbour- FIG. 63. Lymphatics of the prostate (Cuneo and Maicille). a, 6. External iliac glands, c. External iliac prostatic pedicle, d. Retro-prostatic glan- dular nodules, e. Prostatic pedicle of the promontory. /. Gland of the promontory. g. Latero-sacral gland, h. Middle haemorrhoidal gland, t. Middle haemorrhoidal trunks. hood of the prostatic origin of this trunk, two or three small glandular nodules are almost constantly found. 3. Two or three other collecting trunks also start from the pos- terior surface of the gland, and run at first downwards, and then backwards. Tboy enter the sacro-recto-genital aponeurosis, cross LYMPHATICS OF THE PELVIS AND ABDOMEN 179 the lateral surfaces of the rectum, and then ascend on the anterior surface of the sacrum. They do not all terminate in the same manner. The shorter and more external (b, Fig. 63) end in the lateral sacral glands which, as we have already seen, are usually situated internal to the second sacral foramina. The longer and more internal (e, Fig. 63) pass as far as the promontory to terminate in the glands situated there. 4. Finally, from the anterior surface of the prostate may be seen a descending trunk which runs towards the pelvic floor, where it unites with the vessels coming from the membranous portion of the urethra. In company with the latter, it embraces the artery of the corpus spongiosum, and then runs with the internal pudic ; it finally terminates in a gland of the hypogastric group, situated on the intra-pelvic portion of the trunk of the internal pudic artery. This descending prostatic channel, which was observed in the dog by Walker, has also been found in man by Marcille (three times in fifteen subjects). The lymphatics of the prostate to which little attention was given by Mascagni, were for the first time described in some detail by Sappey in 1854 ; but this author hardly described in sufficient detail the course and termina- tion of the prostatic collecting trunks. In 1899, Walker undertook the study of these vessels in the dog and in the monkey ; and quite recently, Cuiieo and Marcille have systematized the arrangement of the prostatic lymphatics in man. BIBLIOGRAPHY. MASCAGNI, loc. cit., p. 44 et tab. XII, Fig. 2. SAPPEY, loc. cit., p. 134, pi. XL VIII, Fig. 4, et Recherches sur la conformation de Vuretre. Paris, 1854, p. 84. WALKER. Ueber die Lymphgefasse der Prostata beim Hunde, Arch, jur Anat. u. Physiol, Annt. Abth., 1899, 1 et 2, p. 1 a 10. STAHR. Bemerkungen liber die Verbindungen der Lymphgefasse der Prostata mit denen der Blase. An. Anz., 1899, 11 1, p. 27-29. CUN o et MARCILLE. Note sur les collecteurs lymphatiques de la prostate. Communication a la Soc. anat.j 31 Janvier 1902. THE LYMPHATICS OF THE BLADDER. The origin of the vesical lymphatics will be studied further on (vide vol. v. p. 123 l ). Here we need only observe that the trend of modern scientists is to deny the existence of absorbent vessels in the vesical mucous membrane, and to maintain that the only network of origin which exists in the blad- der is an intramuscular one. The emergent vessels of this network end in a second network placed on the outer surface of the vesical muscle, under the peritoneum or the umbilico-praevesical fascia. The course and termination of the collectors of this network vary according to their situation on the anterior or posterior surface of the bladder. 1 Treatise of Human Ana'omy. Poirier and Charpy. 180 SPECIAL STUDY OF THE LYMPHATICS FIG. 64. Lymphatics of the bladder in the new-born infant (Cuneo and Marcille). a. External iliac gland (external chain). 6. External iliac gland (middle chain), c. Ex- ternal iliac gland (internal chain), d. Deep inguinal glands, c. Left juxta-aortie gland. /. Gland of the promontory, g. Lateral vesical glands, h. Praevesical glands. 1. Anterior Surface. The collecting trunks coming from the an- terior surface form two groups. The trunks coming from the inferior segment of this surface run almost transversely outwards; and pass into a gland placed on the lateral surface of the pelvic cavity, between the external iliac vein and the obturator nerve, a few millimetres behind the crural ring. The trunks which come from the superior part of the anterior surface are remarkable for their sinuosities. They run upwards and outwards, cross the hypo- gastric artery, passing either above, or more frequently below it, and eventually terminate in the middle gland of the middle chain of the external iliac group. In the course of these lymphatic trunks are placed small glands, which are only visible after injection : they belong to the group of interrupting glandular nodules (vide p. 86). Some of these glands are placed in front of the bladder (praevesical glands) ; they may become hypertrophied in certain pathological con- ditions (Bazy), and may form the starting point of certain prae- vesical phlegmons. Others are placed at the spot where the lym- phatic vessels cross the hypogastric artery (latero-vesical glands. Waldeyer, Gerota). 2. Posterior Surface. The trunks which come from the posterior LYMPHATICS OF THE PELVIS AND ABDOMEN 181 surface also form several groups, (a) The trunks which come from the superior portion of this surface, run outwards describing several curves. They cross the hypogastric artery, where they traverse some small lateral-vesical glands, and terminate in the external iliac gland in which, as we have seen, the superior lymphatics of the anterior Fia. 65.- Lymphatics of the bladder (Cuneo and Marcille). a. Gland of the external chain of the external iliac group, b, b. Collecting trunk of the upper portion of the posterior surface, c. Collecting trunk of the inferior portion of the anterior surface, d. Gland of the promontory, e. Hypogastric gland, situated on the gluteal artery. /. The hypogastric gland, g. Satellite collecting trunks of the inferior vesical artery. h. Collecting trunks about to end in the glands of the promontory. surface also end. (b, Fig. 65). (b) Other trunks pass backwards following the course of the hypogastric artery, and end in a gland which is situated, like the preceding, on the external iliac vein, but more posterior to it, immediately in front of the bifurcation of the common iliac artery, (c) Other trunks which come from the middle M * 182 SPECIAL STUDY OF THE LYMPHATICS segment of the posterior surface, end in the hypogastric glands (<7, Fig. 65). (d) Others finally arising from near the neck of the bladder run directly backwards, and crossing the lateral surfaces of the rectum, ascend on to the anterior surface of the sacrum and ter- minate in the glands situated in the angle of bifurcation of the abdominal aorta, in front of the promontory (7i, Fig. 65). To sum up, the vesical lymphatics end in the external iliac glands, in the hypogastric glands, and in the glands of the bifurcation of the aorta. We may add that the praevesical network is continuous with the network which surrounds the prostate, the vesiculae sem- inales, the vasa deferentia, and the terminal parts of the ureters. Historical and Technical. The lymphatics of the bladder have given rise to numerous researches. We will not here recall the discussions to which the question of the existence of these lymphatics has given rise ; they will be found summarized in the excellent monograph of Pasteau. As regards the arrangement of the collecting trunks and the situation of their terminal glands, we find but very incomplete descriptions given in the classical works. Mas- cagni and Cruikshank, however, appear to have observed the lateral vesical glands. Sappey does not mention them, and wrongly concluded that the lymphatics of the bladder terminate exclusively in the external iliac glands. Pasteau publishes no original work, and confines himself to summarising previous researches. It is only in recent times, that Gerota, and more re- cently, Marcille and one of the present authors demonstrated the topography of the lymphatic glandular apparatus connected with the bladder. The reason why anatomical literature only furnishes us with such vague information on this point is that, the injection of the vesical lymphatics is a somewhat difficult process. With mercury, we have only exceptionally suc- ceeded in injecting them, but with Gerota's method they are shown much more readily. Again, certain rules must be carefully observed. It is useless to try and inject the perimuscular network, for this almost invariably results in the production of an extensive extravasation. The canula must be inserted into the actual thickness of the vesical muscle, and the injected mass must be pressed if possible into the intramuscular network (Cuneo and Marcille). BIBLIOGRAPHY. CRUIKSHANK, loc. cit., p. 304. MASCAGNI, loc. cit., p. 44 et tabl. XII, Fig. 11. SAPPEY, loc. cit., p. 304. GEROTA. Ueber Anatomie und Physiologie der Harnblase. Arch. f. Anat. u. Phijsiol., Phys. Abth., 1897, p. 428. GEROTA. Ueber die Lymphgefasse und die Lymph- drusen der Nabelgegend und der Harnblase, An. Anz., XII, 4 et 5, p. 89. PASTEAU. Etat du systeme lymphatique dans les maladies de la vessie et de la prostate. Th. Paris, 1878 (contient une bibliographic tres complete). WALKER. Ueber die Lymphgefasse der Prostata beim Hunde. Arch. /. Anat. u. Physiol., Anat. Abth., 1899, 1 et 2, p. 1 a 10. CUNEO et MARCILLE. Lymphatiques de la vessie. Communic. Soc. anat., 29 novembre 1901. BAZY, Rapport sur une note de Gerota. Soc. Chirurgie, 7 mai 1902. LYMPHATICS OF THE URETER. Our knowledge of the lymphatics of the ureter is still imperfect. Sappey was only able to inject them in the horse, and only met with them in the muscular coat. In the course of our injections of the vesical lymphatics, we have several LYMPHATICS OF THE PELVIS AND ABDOMEN 183 times seen the subserous network of the bladder extend itself a few millimetres round the ureter. The lymphatics of the ureter end in multiple collecting trunks which pass to the neighbouring glands. LYMPHATICS OF THE KIDNEYS. The lymphatics of the kidneys arise from two networks, one superficial, and the other deep. The superficial network, which was observed by Mascagni, has not been seen by Ludwig and Kolliker. The now classical Capsular artery a Renal artery Spermatic artery nal vein Left spermatic vein FIG. 66. Lymphatics of the kidneys. a/ Right juxta-aortic gland (retro -venous). 6. Prae-aortic gland, c. Right juxta-aortic gland (praevenous). d. Left juxta-aortic gland. researches of Teichmann and Sappey, and the more recent works of Renaut and Stahr, however, leave no doubt as to its existence ; but it is extremely difficult to inject. Immediately underneath the capsule, it is remarkable for the tenuity of its meshes. From this network, two systems of collecting trunks arise which, following Sappey, we may divide into convergent and divergent. The con- vergent empty themselves into the collecting trunks of the deep network, either by immediately sinking into the depth of the kidney, or by running under the capsule only, to join the deep collecting 184 SPECIAL STUDY OF THE LYMPHATICS trunks near the hilum. The divergent trunks perforate the fibrous capsule, and pass into the network which we shall describe further on when dealing with the fatty capsule of the kidney. The arrangement of the deep network has given rise to several discussions into which we need not enter here (vide 1 vol. v. pp. 49, 50). It eventually gives origin to large collecting trunks, varying in number from four to seven, which leave the kidney at the hilum. These trunks course round the artery and the renal vein. They are usually satellites of the vein, some running on its anterior, and some on its posterior surface. The classical authors have only given us somewhat vague informa- tion as to the mode of termination of these vessels, simply stating that these lymphatics terminate in the glands of the hilum, which moreover is incorrect. In his recent monograph on the lymphatics of the kidney, Stahr, who was much struck by the variations shown in different subjects, declares that he finds it impossible to formulate a general scheme for their mode of termination. After examining sixteen kidneys injected by Gerota's method, we have arrived at the following conclusions : The mode of termination of the renal lymphatics varies on the two sides. On ike right, we may divide the vessels into anterior and posterior. The anterior trunks run in front of the renal vein, and pass downwards and inwards and terminate in the prae- venous mass of right j uxta-aortic glands (vide p. 139). They usually terminate in the group of the above-mentioned glands, which is situated on the anterior surface of the vena cava, immediately below the opening of the renal veins into the inferior cava, but one of them may often be seen to end in a gland belonging to the same group, placed much lower down, close to the bifurcation of the aorta. It is equally common to see one of these trunks end in a gland of the prae- aortic group. The posterior trunks are shorter than the preceding, and are placed behind the vein and renal arteries. They terminate in two or three large glands situated behind the inferior vena cava, in front of the right pillar of the diaphragm. These glands belong to the retro- venous group of the right j uxta-aortic glands. Their efferent vessels pass through the right pillar of the diaphragm, traversing it through the same orifice as the great splanchnic nerve, and terminate in the thoracic duct. On the left, the collecting trunks, which leave the kidney at the hilum, terminate in four or five glands which belong to the j uxta-aortic group of the correspond- 1 Treatise of Human Anatomy. Poirier and Charpy. LYMPHATICS OF THE PELVIS AND ABDOMEN 185 ing side, which are thus ranged on the left side of the abdominal aorta. The highest of these glands are situated in front of the left pillar of the diaphragm, through which their efferent vessels pass on their way to join the thoracic duct (vide Fig. 66). To sum up, the lymphatics of the kidneys end principally in the juxta-aortic glands of the corresponding side, and accessorily in the prae-aortic glands. In any case, it is, if not absolutely incorrect, at least insufficient, to state that the lymphatics of the kidney terminate in the glands placed at the level of the hilum of these organs. At the level of the hilum, however, we may meet with some small glandular nodules, but by reason of their contiguity and their small size, they should be regarded as belonging to that variety of gland which we have described above as the interrupting glandular nodule (Schaltdriisen), and which it is important to distinguish from the regional glands which are much more constant in their presence and situation (Stahr). One of these nodules is, however, distinguish- able by its relative frequency and by its fairly constant situation beneath the right renal vein, in the angle which this vessel forms with the inferior vena cava. The fatty capsule of the, kidney possesses a rich lymphatic network, which has recently been well described by Stahr. The efferents of this network end in the same glands as the collectors from the kidney itself. The network of the fatty capsule communicates, as we have seen, with the lymphatics of the kidney : and it is not rare to find, during the progress of epithelial cancers of this organ, lines of new growth in the fatty capsule. Technique. The injection of the superficial lymphatics of the kidney is extremely difficult, whatever method is employed. To show the deep lym- phatics, Sappey advises that a current of water be passed through the renal artery. The water returns at once by the vein and by the lymphatics which are then rendered very apparent. We have always injected these vessels with the greatest ease by Gerota's method. All that is required is; to press the injected mass well into the parenchyma, and preferably into the medullary substance, where the vessels are more numerous and larger. The previous flushing of the kidney with water moreover much facilitates this injection. To distend the network of the fatty capsule, Stahr advises us to use subjects who have emphysema of the perirenal cellular tissue. BIBLIOGRAPHY. MASCAGNI, loc. cit., p. 44 et tab. XIV. SAPPEY, loc. cit., p. 123 et pi. XLVT, Fig. 9. TEICHMANX, loc. cit., p, 8. RINDOWSKY. Die Lymphgefasse der Niere. Verh. d. 3. Vers. ntss. Naturf. zu Kiew, 1871. DISSE. Zur Anatomie der Niere, Sitzungsber. der Gesellsch. zur Beforderung der gesammten Naturwissensch. zu Marburg, 1898, 11 8. HERMANN STAHR. Der Lymphapparat der Niere, Arch. /. Anat. u. Phys., Anat. Abth., 1900, p. 40. CUNEO. Note sur les lymphatiques du rein, Bull. Soc. anat., Paris, 28 fevrier 1902. 186 SPECIAL STUDY OF THE LYMPHATICS LYMPHATICS OF THE SUPRARENAL CAPSULES. The lymphatics of the suprarenal capsules, whose mode of origin will be studied together with the structure of these organs, end in four or five collecting trunks, which emerge at the same point as the large central vein. These trunks terminate in the juxta-aortic glands of the corresponding side. In several subjects, we have seen some of these collecting trunks perforate the pillars of the diaphragm, and end in the glands placed between the posterior surface of these pillars and the vertebral column. 5. LYMPHATICS OF THE SUB-DIAPHRAGMATIC PORTION OF THE DIGESTIVE TUBE. The lymphatics of the sub-diaphragmatic portion of the digestive tube are considerably developed, in proportion to the important part they have to play in the absorption of food which has already been altered by the digestive juices. We will not here consider the histo- logical origin of these vessels within the intestinal coats ; this will be described together with the structure of the different segments of the sub-diaphragmatic portion of the intestinal tube. We will now study more especially the macroscopic arrangement of the networks of origin, and the course and termination of the collecting trunks. LYMPHATICS OF THE ANUS AND RECTUM. (1) NETWORKS OF ORIGIN. The lymphatic vessels of the anus and rectum arise from two networks ; one is attached to the muco-cutaneous lining of the ano-rectal region ; the other belongs to the muscular coat. (A) The muco-cutaneous network may be divided into three regions : inferior, middle and superior. (a) The inferior region corresponds to the skin at the margin of the anus. Here, there are two superposed networks, one is superficial or cutaneous, and is enclosed within the actual thickness of the skin, while the other is deep or subcutaneous. The injection of these networks is easy, and it generally suffices to make two or three punctures to fill them entirely. Their meshes are extremely close, and when the injection is made with mercury, the cutaneous network appears as a continuous layer, so that a lens is necessary to show the details (vide Fig. 67). (b) The middle region corresponds to the skin bordered area of the anus ; its upper limit is therefore formed by the ano-cutaneous line (white line). The meshes of this network, which are much coarser than those of the preceding region, have a vertical direction. (c) The upper region corresponds to the anal mucous membrane LYMPHATICS OF THE PELVIS AND ABDOMEN 187 properly so called, and to the rectal mucous membrane. In the former, the lymphatic network is little developed. In the latter, on the contrary, it is extremely rich, but the fragility of its meshes Superior region Superior hcemor- rhoidal artery Superior hcemor- rhoidal gland Paracentral gland Muscular coat Mucous coat Middle region Inferior region FIG. 67. Lymphatics of the rectum (after Gerota). The posterior wall of the rectum is cut to show the mucous membrane ; through a large window made in the upper part through the fibrous coat, the blood vessels may be seen. render its injection difficult. As is the case in the rest of the large intestine, there are two superposed networks, one mucous and the other sub-mucous. 188 SPECIAL STUDY OF THE LYMPHATICS (B) The network of the muscular coat is very difficult to inject. The trunks coming from this network unite with the collecting trunks from the nmco-cutaneous networks. (2) COLLECTING TRUNKS. Each of the muco-cutaneous linings possesses distinct efferents. (A) The inferior region gives rise to from three to five trunks on each side. These run towards the inguinal region, some coursing on the internal aspect of the thigh, others over the perineum, or at the level of the perineo-crural. f old. haemorrhoidal channel (Cuneo and a. Gland of the external chain of the external iliac glands. 6. Gland of the middle chain of the external iliac glands, c. Transverse lymphatic pedicle of the prostate, d. Retro- prostatic glands, e. Posterior lymphatic pedicle of the prostate. /. Glands of the pro- montory, g. Lateral sacral glands, h. Middle haemorrhoidal gland, t. Rectal afferent of this gland. LYMPHATICS OF THE PELVIS AND ABDOMEN 189 Their course is very irregular. They describe numerous bends, and often bifurcate en route. They end in the superficial inguinal glands ; but their mode of termination obeys no absolutely fixed rules. They are usually tributaries of the supero-internal group ; but they may frequently be seen to terminate in the infero-internal group, or to empty themselves into both these two groups at the same time. It is much more rare to see them terminate in a gland belonging to one of the external groups. In. twenty-eight cases, Gerota has seen the cutaneous lymphatics of the anus end, fifteen times in the supero-internal group, eight times in the infero-internal group, four times in these two groups at the same time, and once in the supero-internal, infero-internal and infero-external groups. (B) The middle region possesses numerous efferents which we may divide into indirect and direct. The former ascend in the columns of Morgagni. and terminate in the network of the rectal mucous membrane (vide Fig. 87). The direct efferents perforate the rectal Avail and gain the neighbouring glands. Taking their course and termination as the basis for our classification we may divide them into three groups : (a) Some of them perforate the rectal wail slightly above the levator ani, then ascend on the lateral walls of the rectum, traverse the para-rectal glands which will be described further on, join the collectors coming from the superior region and terminate, as the latter do, in the glands of the meso-rectum. (6) Others, coming from the muscular walls of the rectum at the same level as the preceding, are satellites of the middle haemorrhoidal vessels : they constitute the middle haemorrhoidal channel. They usually terminate in a gland placed in the course of the middle haemorrhoidal artery at some distance from the lateral wall of the pelvis, (c) The collecting trunks of the third group (inferior haemorrhoidal channel), emerge beneath the insertion of the levator ani, and may be regarded as corresponding to the system of the inferior haemorrhoidal vessels. As a matter of fact, however, it is rarely that they follow these vessels closely. Most frequently they have a much more simple course ; for, after running a very short distance in the adipose tissue of the ischio-rectal fossa, they perforate the levator ani and terminate in a gland situated at the commencement of the internal pudic artery, within the pelvis. The satellite trunks of the middle haemorrhoidal vessels are somewhat difficult to inject, especially when mercury is used. The old authors made no mention of them. Quenu and Gerota observed them, but were only able to 190 SPECIAL STUDY OF THE LYMPHATICS inject them in a small number of cases. Marcille, on the contrary, employ- ing Gerota's method was able to demonstrate these vessels in nearly every case. We therefore regard this middle haemorrhoidal channel as constant ; but it does not always present the very simple arrangement which we have just in- dicated ; in fact, one of the satellites of the middle haemorrhoidal artery may be seen to end in the middle gland of the internal chain of the external iliac group, or in the lateral sacral glands : Now it is important to notice that the glands into which these aberrant vessels empty themselves, are precisely those in which the normal efferents of the middle haemorrhoidal gland end (vide Fig. 68). We may therefore regard these lymphatic trunks as afferents of the middle haemorrhoidal gland which, having passed by their first glandular relay have directly reached their second. The trunks which correspond to the system of the inferior haemorrhoidal vessels are passed over in silence by the majority of authors. Marcille and one of the present authors have injected them several times ; but the number of our observations has been insufficient to enable us to affirm the constancy of this inferior haemorrhoidal route. (C) The collecting trunks of the superior region pass through the muscular coat of the rectum at different levels. They are most frequently satellites of the vessels, and there are usually two for each artery. After perforating the muscular coat of the rectum, they run obliquely upwards and backwards, and reach the glands contained in the meso-rectum. In their perirectal course, they traverse some small glands which have been well described by Gerota and which we will call para-rectal glands (ano-rectal glands of Gerota). These glands vary in number from four to seven, and are placed on the muscular layer, and covered by the fibro- serous coat of the rectum. They are met with especiallv in the region of the ampulla. The lowest of them is situated imme- diately above the levator ani. The superior glands on the contrary, may be found projecting underneath the serous layer. We regard these glands as simple interrupting glandular nodules placed in the course of the juxta-rectal collecting trunks. Apart from pathological cases they are always very minute. As regards the glands placed in the meso-rectum, or, if we prefer to call it so, the terminal portion of the pelvic meso-colon, they are grouped round the trunk of the superior haemorrhoidal artery. They are always of considerable size : they are the true regional glands of the vessels which spring from the superior lymphatic region of the rectum. The arrangement of the ano-rectal collecting trunks may be thus summarized : These vessels may be divided into three groups : an inferior group, which comes from the skin of the margin of the anus, and is a tributary of the superficial inguinal glands ; a middle group, which comes from the region of the white line and ends in LYMPHATICS OF THE PELVIS AND ABDOMEN 191 the hypogastric glands ; a superior group, which springs from the mucous membrane of the anus and rectum, and terminates in the glands of the meso-rectum, after traversing the para-rectal glandular nodules. The superior group corresponds to the superior haemor- rhoidal vessels. The middle group corresponds to the middle and inferior haemorrhoidal vessels. The inferior group has no homo- logue in the arterial system. LYMPHATICS OF THE ILIO-PELVIC COLON. The lymphatics of the ilio-pelvic colon at first traverse some small glands which are attached to the terminal branches given off by the para-intestinal arch and formed by the anastomosis of the three sigmoid arteries. They then terminate in glands placed over the inferior mesenteric artery. LYMPHATICS OF THE DESCENDING COLON. The lymphatic vessels of the descending colon present a somewhat similar arrangement to that of the ilio-pelvic colon. We need only note the poorly developed glandular apparatus attached to this part of the large intestine. LYMPHATICS OF THE TRANSVERSE COLON. The lymphatic apparatus of the transverse colon is much more developed. The juxta-intestinal glands (vide p. 142) are here numerous, especially in the neighbourhood of the two extremities of the transverse colon. Further, one almost constantly finds one or two large glands situated in the angle of the bifurcation of the middle colic, as well as two or three others placed along the trunk of this artery. The trunks coming from the latter pass into the glands of the superior mesenteric chain. The lymphatics of the transverse colon communicate to a large ex- tent with those of the great omentum, so that they are brought into relation with the lymphatics of the inferior border of the stomach. LYMPHATICS OF THE ASCENDING COLON. The collecting trunks emanating from the ascending colon at first traverse some few juxta-intestinal glands : they then meet a gland, which is however inconstant, placed on the course of the ascending colic artery, and finally terminate in the glands of the superior mesenteric chain. LYMPHATICS OF THE COECUM AND APPENDIX. The lymphatics of the coecum and appendix are much more developed than those of the other segments of the large intestine. This is especially true in the case of the appendix, the lymphoid tissue of which is known to be abundant. The mode of origin of these vessels, and the arrangement of the appendicular lymphoid apparatus will be studied 192 SPECIAL STUDY OF THE LYMPHATICS further on (vide vol. iv. p. 334, Fig. 178 1 ). We will therefore confine ourselves here to indicating the arrangement of the collecting trunks of the coecum and the appendix, and the topography of their terminal glands. The coeco-appendicular collecting trunks follow pretty closely the course of the blood vessels. This fact will enable us to divide them into three groups : the anterior coecal, the posterior coecal and the appendicular trunks, which respectively accompany the vessels of this name. (a) The anterior co zeal collecting trunks appear on the anterior surface of the coecum. They run upwards and in- wards, traversing one or tw r o small glands situated in the thick- ness of the anterior ileo-coecai fold, and then terminate in a glandular mass placed on the ter- minal segment of the ileo-coecal artery (vide Fig. 69). (b) The posterior FIG. GO.-Lymphatics of the coecum and appendix (anterior COeCCtl Collecting trunks view), follow the course of a. Ileo-coecal glands. b. Anterior coecal lymphatics. , i f f i_ c. Anterior coecal glands, d. Gland of the appendix (sub- tlie arter y ileal group), e. Appendicular afferents of this gland. name. Like the pre- ceding, they traverse some small glands the posterior coecal. The latter, from three to six in number, are situated on the posterior aspect of the coecum, at the junction of this surface with the internal surface. Except in those rare cases where the coalescence of the posterior surface of the coecum and the parietal peritoneum is complete, these glands are covered by the visceral layer of peritoneum which binds them to the posterior surface of the coecum. The posterior coecal lymphatics terminate in the ileo-coecal glandular group (vide Fig. 70). 1 Treatise of Human Anatomy. Poirier and Charpy; LYMPHATICS OF THE PELVIS AND ABDOMEN 193 (c) The collecting trunks of the appendix, four or five in number, run up between the layers of the meso-appendix, accompanying the appendicular artery. Like this artery, they cross the posterior surface of the terminal segment of the ileum, then penetrate into the mesentery, and terminate in the ileo-coecal glandular group (vide Fig. 70). In their course, these lymphatics traverse some small glands which we class under the generic term of appendicular glands. In the large majority of cases, these glands from one to three in number, are placed in the retro-ileal segment of the meso- ; Vr Ifeo-ca'cal artery ~r Potterior crccnl artery Fig. TO. Lymphatics of the coccum and appendix (posterior view), a. Ileo-coecal glands, fc. Appendicular glands (retro-ileal group), c. Retro-coecal glands. appendix ; they may then be styled the retro-ileal appendicular glands. More rarely we find one or several glands in the sub-ileal portion of the meso-appendix ; these are the sub-ileal appendicular glands. Finally, some of the glands of the meso-appendix may be placed immediately against the coecum, above the origin of the appendix ; these are the juxta-coecal appendicular glands. Tixier and Viannay, who have recently undertaken the study of the topo- graphy of the appendicular glands, have well described the arrangement of these three groups which we have styled the ileo-appendicular, appendicular and coeco-appenclicular. The ileo-appendicular group (appendicular, retro- ileal group) is the most constant. It was present in 36 out of 100 cases. In 22 of these 100 cases, it was formed by only a single gland ; in 10 of these 100 cases, 2 glands were present ; in 4 of these 100 cases, there were more than 2 glands. The appendicular group (appendicular, sub-ileal group) was found in 12 out of 100 cases. In 14 of these, Tixier and Viannay proved the 194 SPECIAL STUDY OF THE LYMPHATICS presence of the coeco-appendicular group (appendicular juxta-coecal group). Finally in 6 per cent, there was no trace of glands in any part of the meso- appendix. This possible absence of appendicular glands well shows that these glands, like the prae- and retro-coecal glands, are simple interrupting glandular nodules (Schaltdruse) interposed in the course of the coeco- appendicular lymphatics. The true regional glands of these vessels are the glands placed in the mesentery round the ileo-coecal artery. The appendicular lymphatics are therefore, eventually, tributaries of the glands which form the terminal segment of the superior mesenteric chain. Some authors are of opinion that the appendicular tymphatics have a much more complicated mode of termination. " I have so often found," says Lock- wood, " a chain of inflamed lymphatic glands along the internal border of the colon, behind the ascending meso-colon, that I have arrived at the conclusion that this is the chief route followed by the lymphatics of the appendix. Other lymphatics without doubt pass into the mesenteric glands. The lymphatics of the appendix also empty themselves into the glands of the iliac fossa, lying one behind the other along the length of the external iliac artery. Some also run along the appendiculo-ovarian ligament which pass into the right broad ligament, and into the glands of the right lateral wall of the pelvis, close to the internal iliac artery/' This classification, which is accepted by Tixier and Viannay, appears to us absolutely visionary. The only normal terminations of the coeco-appenclicular lymphatics are the glands of the ileo-coecal group. However, the subserous network of the coecum anas- tomoses with that of the adjacent parietal peritoneum, and it is through this network that the coeco-appendicular lymphatics may communicate with some of the neighbouring glandular groups. Clado has described an anastomosis between the lymphatics of the appendix and those of the right ovary ; this anastomosis runs in the appendiculo-ovarian ligament. Tixier and Viannay have found a small lymphatic gland in this fold. We have never proved the existence of the anastomosis described by Clado, and we formally deny its presence. BIBLIOGRAPHY. TUFFIER. Btude sur le coecum et ses hernies. Archives yenerales de medecine, 1887, p. 641. CLADO. Appendice ca?cal. Mem. de la Soc. de biol., 1892. LAFFORGUE. Recherchcs anatomiques sur 1'appendice vermiculaire du caecum. Journ. de VAnat. et de la PhysioL, 1893. LOCK- WOOD. Note upon the lymphatics of the vermiform appendix, Journ. of Anat. and Physiol., 1900, t. XXXIV, p. xni. TIXIER et VIANNAY. Xote sur les lymphatiques de 1'appendice ileocaccal. Lyon medical, 1901. AUGUY. De I'adenopathie appendiculaire. These Lyon, 1901. BONJOUR. Des adenopathies peri-appendiculaires. These Paris, 1901. QUENU. Communic. Soc. Chirurgie, 1 mai 1902. LYMPHATICS OF THE SMALL INTESTINE. Like the lymphatics of the large intestine, the lymphatics of the small intestine form two systems relatively independent of each other, one of which is attached to the mucous layer, and the other to the muscular coat. Details of the origin of these vessels and their relations with the rich lymphoid tissue which is connected to them will be studied further on (vide vol. iv. p. 300 1 ). The mode of termination of the collecting trunks of the small intestine is not the same in the region of the jejuno-ileum as in that of the duodenum. 1 Treatise of Human Anatomy. Poiricr and Charpy, LYMPHATICS OF THE PELVIS AND ABDOMEN 195 LYMPHATICS OF THE JEJUNO-ILEUM. The collecting trunks, which are extremely numerous, make their appearance in the neighbourhood of the mesenteric border of the intestine. If examined in the living subject, during intestinal digestion they appear as slightly bossed channels of varying calibre, especially noticeable on account of their milky appearance. They terminate in the glands contained in the mesentery. Though these glands appear, at first sight, to be indiscriminately scattered between the two folds of the mesentery, if observed more attentively, we may convince ourselves that they are arranged on some fairly definite plan. It is also possible to divide them into three groups which vary in importance and signification. (a) A primary group comprises some small glands placed on the course of the terminal arterioles springing from the last an- astomotic arch, or actually over the arch itself. Some- times, especially at the commencement of the jejunum, these glands are immedi- ately contiguous to the intestine and may even lie on the intestine itself. As we have seen, they are simple interrupt- ing glandular nodules (Schaltdriise) which have no morphological fixity. (6) A second group comprises some glands placed in the course of the primary branches of the superior mesenteric artery and at the level of the first anastomotic arch formed by these vessels. These glands, which are much larger than the preceding, are the true regional glands of the jejuno-ileum. (c) Finally, a third group of glands is found round the trunk of the superior mesenteric artery and more particularly round the commencement of this vessel. This group does not properly belong to the jejuno-ileum, nevertheless it receives the efferents of Fig. 71. Lymphatics of the small intestines (after Sappey) 1. Loop of small intestine. 2, 3, 5, 7. Lymphatic col- lectors. 4. Juxta-intestinal gland. 6. Mesenteric vein. Mesenteric artery. 8. 196 SPECIAL STUDY OF THE LYMPHATICS the regional glands of the coecum, the ascending and transverse colon, the duodenum and even the afferents of certain glands connected with the stomach (vide p. 146). The glands are especially numerous in that portion of the mesen- tery which corresponds to the jejunum. There is a progressive diminution in the number of glands in each given segment of the mesentery until the terminal segment of the ileum is reached. Gland of the hepatic chain. Hepatic artery. Splenic vein. Superior mesenteric gland. Gland of common bile duct* Gland of common bile duct. Gastro-duodenil artery. Retro-pincreatiz gland. Portal vein. Ketro-pincre'.itic gland. Helro-pancrsatic gland. Fig. 72. Retro-pancreatic glands. We must, however, always remember that in the ileo-coecal region the glands again reappear in numbers and form an important mass round the ileo-coecal artery. The mesenteric glands constitute one of the most important glandular centres in the human system. They vary in number from 130 to 150 (Quain), and their size varies greatly in different subjects. In certain pathological conditions they may form very large tumours which cause serious trouble in the abdominal cir- culation. In certain animals, they are grouped into a compact LYMPHATICS OF THE PELVIS AND ABDOMEN 197 mass which the old anatomists described under the name of pancreas of Aselli. LYMPHATICS OF THE DUODENUM. The lymphatics of the duo- denum end in numerous collecting trunks which are arranged on the same plan as those of the jejuno-ileum, but the pancreas divides these vessels, like the corresponding blood vessels, into two groups : an anterior group, the vessels of which end in glands placed on the prae-pancreatic vascular arch ; a posterior group, the lymphatics of which terminate in the satellite glands of the retro-pancreatic arch. From these glands, namely the prae- and retro-pancreatic, run two systems of efferents. Some, ascending, terminate in the glands of the hepatic chain. Others, descending, are grouped round the superior mesenteric artery, at the spot where this vessel crosses the third part of the duodenum. The close relations which exist between the lymphatics of the duodenum on the one hand and those of the common bile-duct and pancreas on the other, should be noticed. We shall see later on that anastomoses are also present between the lymphatics of the duodenum and those of the pyloric portion of the stomach (vide p. 201). LYMPHATICS OF THE STOMACH. The origin of the lymphatics of the stomach will be studied together with the structure of that organ (vide vol. iv. p. 241). Here we need only call to mind the fact that the lymphatics of the stomach, like those of the intestine, ought to be divided into mucous and sero-muscular. The lymphatics which arise in the mucous membrane finally end in a submucous network ; from this, collecting trunks arise which, in the neigh- bourhood of the curvatures, perforate the muscular coat and finally terminate in the sero-muscular collecting trunks. The latter spring from a sub-peritoneal network in which all the lymphatics which come from the muscular coat and serous layer end. These musculo-serous collecting trunks may be divided into three groups : some of which are directed towards the small, others towards the large curvature ; while a third group runs towards the great tuberosity. 1 . The collecting trunks of the first group (superior or converging trunks of Sappey) are the most important and the largest. Ac- cording to Sappey, they may usually be reckoned as from six to eight. In different subjects they run either singly or in triplets. The majority of these trunks converge towards the glands of the small curvature, which are, as we have already seen (p. 143), N 198 SPECIAL STUDY OF THE LYMPHATICS situated around the spot where the coronary artery approaches the small curvature. Their direction varies according to their origin ; thus, the collecting trunks which spring from the body of the stomach are quite vertical, those which arise from the pyloric vestibule point obliquely upwards and to the left ; and the trunks issuing from the pylorus run parallel to the small curvature. On FIG. 73. General view of the subperitoneal network of the stomach, injected by Gerota's method (Cuneo). 1. Left pneumogastric. 2. Praecardiac glands. 3. Right pneumogastric. 4. Coronary artery, o. Coronary vein. 6. Gland of the small curvature. 7. Hepatic artery. 8. Right gastro-epiploic artery. 9. Sub-pyloric gland. 10. Right gastro-epiploic vein ending in the middle colic vein. the contrary, the lymphatics which come from the cardia or the sub-cardiac zone, descend obliquely downwards and to the right towards the point of common convergence. In a general way then, all these trunks have a direction parallel to that of the coronary vessels. However, one or two very fine vessels, which come from the upper LYMPHATICS OF THE PELVIS AND ABDOMEN 199 part of the pylorus, run from left to right towards the pyloric artery and join the efferent trunks of the retro-pyloric glands. 2. The collecting trunks of the second group, or collecting trunks of the large curvature, are more numerous but smaller than the preceding. They vary in number from twelve to eighteen. They usually, but not necessarily, accompany the branches sent by the gastro-epiploic vessels to the stomach. All these collecting trunks end in the sub-pyloric glands (vide p. 146). The lymphatics coming from the pylorus or the pyloric vestibule soon join these glands by a vertical or slightly oblique course. As regards the other collecting trunks which come from the body of the stomach, instead of running directly downwards and to the left with an obliquity varying with their situation, they descend vertically as far as the vascular arch which runs along the great curvature ; there they quickly change their direction and run parallel to this arch. During their course, they blend together, forming two or three trunks which anastomose with one another and finally end in the sub-pyloric glands (vide Fig. 73). 3. The third group includes all the trunks coming from the great tuberosity. They vary in number from three to six. They run in the gastro-splenic omentum, but do not accurately follow the course of the vasa brevia and the left gastro-epiploic arteries. They then penetrate the splenico-pancreatic omentum, and terminate in the glands placed in this omentum, close to the hilum of the spleen. To sum up, we may say that, in a general way, the collecting trunks of the small curvature converge towards the point at which the coronary artery approaches the stomach, and pass into the glands of the coronary chain. The collecting trunks of the large curvature run from left to right towards the sub-pyloric glands. Finally, the trunks which spring from the great tuberosity are directed from left to right towards the hilum of the spleen, and end in the glands of the splenic chain. We have already described these glandular groups (vide prae-aortic glands, p. 141, and Figs. 46 and 47) and therefore will not return to this point, but we must here note the possible presence of little interrupting glandular nodules in the course of these different collecting trunks. In certain cases, these nodules may be placed within the actual thickness of the walls of the stomach at avariable distance from the curvatures. Letulle (Soc. Anat., Dec. 29, 1897) was the first to draw attention to this arrangement, of which one of the present authors has met with three examples. These parietal gastric glands usually occupy the subserous layer or the superficial portion of the muscular coat. Lymphatic Territories. As we have seen, in the stomach there are three 200 SPECIAL STUDY OF THE LYMPHATICS distinct lymphatic territories, to the arrangement of which one of .the present authors drew attention in his thesis. These territories correspond to the three groups of collecting trunks which we have described. The territory of the collectors of the small curvature is divided from the others by a line which commences a little to the left of the cardia, and runs on both surfaces of the stomach following a line nearly parallel to the large curvature. But this line which indicates the parting of the lymph, if one may so speak of it, is much nearer the large than the small curvature. We may reckon ap- proximately that it leaves below it, a third only of the surface of the organ. It is important, however, to remark that in the pyloric region, this line tends to become raised and to be placed at an equal distance from the large and the small curvature. The limit of the territories of the collectors of the second and third groups is more difficult to determine accurately ; it is, moreover, of no great practical interest. It usually corresponds to the junction of the horizontal with the 3 vertical portion of the large curvature. This classification is the same on the two surfaces of the organ and applies as well to the lymphatics of the mucous membrane as to those of the musculo- serous coat. From this description it follows that the largest and most im- portant of the three lymphatic territories of the stomach is that of the col- lectors of the small curvature ; these collectors taken together represent the 74 Lymphatic territories of the principal lymphatic channel, whereas the collecting trunks of the other two 1. The coronary or the principal current, groups are onlv accessory channels. 2. Right gastro-epiploic current. 3. Splenic Anastomoses. The lymphatic appara- tus of the stomach contracts im- portant relations with the lymphatics of neighbouring organs. These relations are of two kinds : some are effected by the anastomoses which exist between the different gastric networks with the two adjacent portions of the digestive tube, viz. the oesophagus and duodenum ; others are the result of the presence of glandular groups which are common to the gastric lymphatics and those of neighbouring organs, viz. the liver, pancreas, and spleen. We shall here only lay stress on the former. The two principal networks of the stomach, viz. the submucous and the subserous networks, communicate largely with the two homologous networks of the abdominal portion of the oesophagus. As is shown in Sappey's fine plates, there is even a true continuity between the gastric and oesophageal networks. This anatomical arrangement is thoroughly in accord with known facts of pathological anatomy, which teaches us that neoplasms of the cardia easily infect the inferior portion of the oesophagus and inversely. Does the same hold good in the case of the duodenum ? This question must be discussed separately for the subserous and for the submucous network. Sappey's plate shows an absolute continuity between the subserous net- work of the stomach and that of the duodenum. According to Most, on the contrary, there is no communication between these two networks, and in the Fig. LYMPHATICS OF THE PELVIS AND ABDOMEN 201 pyloric region a trunk having more or less annular direction forms a very clear limit to the subperitoneal gastric network. Our researches have led us to the same conclusions as Mnst's, that is. so far as the absence of communication between the subserous network of the stom- ach and the corresponding part of the duodenum is concerned, but we have never been able to inject the annular vessel to which he alludes. In one case, we saw a collecting trunk of the pylorus break through the gastro-duodenal limit, and run a few millimetres on to the commencing portion of the duodenum, and reach a gland belonging to the sub-pyloric group, which was much drawn to the right side. Nevertheless, we do not wish to raise the slightest doubt as to the existence of communications between thesubmucous networks of the stomach and duo- denum. One of the present writers has several times shown the existence of these communications, and Most has even succeeded in filling the collecting trunks of the initial portion of the duodenum and their glands, by injecting the mucous membrane of the pylorus. We must, however, recognize the fact, that these anastomoses between the lymphatics of the gastric mucous mem- brane and those of the duodenal mucous membrane do not show a high grade of development ; but none the less they play a very important part in those cases where the duodenum is invaded by cancer of the pj'lorus. BIBLIOGRAPHY. MASCAGNI, loc. cit., p. 49 et tab. XVIII. SAPPEY, loc. cit., p. 76 et suiv.,pl. XXV, Fig. 1. MOST. Ueber die Lymphgefasse und die regionare Lymphdriisen des Magens, etc. Arch. /. klin. Chir., LIX, 1, p. 175. CUXEO. De 1'envahissement du systeme lymphatique dans le cancer de 1'estomac et de ses consequences chirurgicales. These Paris, 1900. CUNEO et DELAWARE. Anatomie et Histologie des lymphatiques de 1'estornac. Journ. de VAnat. et de la PhysioL, 1900. LYMPHATICS or THE LIVER. As we shall see further on (vide 1 vol. iv. p. 766), we have not yet any perfectly definite knowledge as to th arrangement of the lymphatic channels within the hepatic lobules. On the other hand, it is easy to demonstrate the lymphatic networks in the interlobular connective tissue. From this network numerous collecting trunks start, and these may be divided into two chief groups. Some, springing from the peripheral lobules, run towards the surface of the hepatic gland passing underneath the peritoneum : these are the superficial collectors. Others, coming from lobules more deeply situated, accompany the branches of the portal vein or the hepatic veins and emerge at the point of entrance or exit of these vessels. These are the deep collectors. 1. The Superficial Collecting Trunks. We will study first the collecting trunks on the superior and then those on the inferior surface. 1. THE COLLECTING TRUNKS ON THE SUPERIOR SURFACE. These may be divided into three groups : posterior, anterior and superior. (a) The posterior collecting trunks run towards the posterior surface of the liver. They may be divided into right, middle and 1 Treatise of Human Anatomy. Poirier and Charpy. 202 SPECIAL STUDY OF THE LYMPHATICS left. The right trunk, which is usually single, appears near the 2 2 D 5 6 7 989 D 12 13 - E II Fig. 75. lymphatics on the superior surface of the liver (Sappey). A, A. Right lobe of liver. B, 13. The left lobe. C, C. The suspensory ligament which partly hides the superior surface of the left lobe. D, D. A triangular segment of the dia- phragm which has been incised at the level of the attachment of the suspensory ligament. E. Left triangular ligament of the liver. F. Inferior extremity or base of the gall bladder. 1,1. Large lymphatic trunk situated on the right border of the right lobe ; this trunk descends on to the concavity of the diaphragm and passes into one of the glands which lie on the head of the pancreas. 2, 2, 2, 2, 2. Smaller and shorter trunks which turn round the upper border of the liver ; all terminate in the small glands situated round the inferior vena cava, immediately above the diaphragm. 3. Another trunk, which takes an opposite direc- tion to the preceding, and which turns round the inferior border or edge of the gland, and then runs on to the opposite surface towards the glands of the hilum. 4, 4, 4, 4. Trunldets which spring from a small group of convergent branches on the surface of the liver, and which plunge almost at once into the hepatic tissue and then rim in the channels of Glisson's capsule. 5, 5. A very beautiful network which corresponds to the adherent border of the suspensory ligament. 6, 6. Trunks in which all the little branches of this network end. 7. A group of convergent trunks which start from the same vessels and which run obliquely between the two layers of the suspensory ligament. 8. A very large trunk formed by the fusion of the preceding trunks ; it also passes obliquely through the diaphragm, and then creeps along the anterior portion of its convex surface. 9, 9. Glands in which its branches end. 10. Another trunk also situated in the suspensory ligament ; it arises from the network which corresponds to the base of this fold, is directed downwards, and then passes into the longi- tudinal fissure of the liver and ramifies in one of the glands of the hilum. 11, 11. Network resting on the left lobe of the liver ; this is only seen owing to the transparency of the liver substance. 12. A group of trunks which ascend towards the superior border of the left lobe where they bend, and then run towards the glands situated round the inferior vena cava. 13. Another more important group which at first follows the same course, but, after traversing the left triangular ligament, is inclined downwards and inwards, towards the glands of the terminal part of the oesophagus, in which it is lost. 14, 14, 14. Trunks which disappear almost immediately, penetrating into Glisson's capsule. right extremity of the liver. It runs downwards and backwards and penetrates into the right triangular ligament. It then attaches LYMPHATICS OF THE PELVIS AND ABDOMEN 203 itself to the concave surface of the diaphragm, then crosses the / 11 12 13 13 6D 6 6 6 A* 1 Fig. 76. Lymphatics of the inferior surface of the liver (Sappey). A, A. Large or right lobe of the liver. B, B. Small or left lobe. C. Quadrate lobe. D. Spigelian lobe. E. Cord resulting from the obliteration of the umbilical vein. F. Gall bladder. H. Left triangular ligament of the liver. /. Corresponding part of the diaphragm. A'. The most projecting part of the superior or convex border of the liver. 1, 1. Two large lymphatic trunks which arise in the neighbourhood of the right border of the liver, and run along the superior border, terminating in one of the glands which sur- round the inferior vena cava at its entrance into the thorax. 2. Large lymphatic trunk coming from the central portion of the inferior surface of the right lobe, which runs towai'ds the hilum of the liver and passes into the gland corresponding to the neck of the gall bladder. 3, 3. Other important trunks which also arise round the gall bladder, and anastomose on the interior surface of the latter, and then pass to the glands situated on the inferior border of the hilum of the liver. 4. Two trunks which have the same origin as the preceding ; but, instead of running on the free surface of the gall gladder, they pass in front of its attached surface, and end in the same glands ; their course is indicated by dotted lines, and they ar only ^isible when the gall bladder has been previously detached. 5, 5. Trunks which also arise from the inferior surface of the right lobe, in a lymphatic network, but which dis- appear almost at once and follow the course of the divisions of the portal vein, and are directed towards the hilum. 6, 6, 0. Small trunks which come from the Spigelian lobe, and the glands in which they terminate. 7, 7. Vessels springing from the quadrate lobe. 8, 8. Principal lymphatic trunks of the left lobe. 9, 9. Other trunks which arise from the surface of the same lobe, but which, immediately after their origin, plunge into the liver substance, to run with the vessels of Glisson's capsule. 10. Trunk which we have seen, arises from the superior surface of the left lobe ; it accompanies the umbilical cord and terminates in one of the glands of the hilum. 11, 11. Two trunks, visually large, which also arise from the superior surface of the left lobe, and which traverse the corresponding triangular ligament and end in a gland situated at the posterior extremity of the longitudinal fissure ; from this gland run vessels which end in the glands of the hilum. 12. Other trunks which also come from the superior surface of the left lobe and end in the same glands as the preceding. 13, 13. Glands in which the vessels coming from the superior surface of the liver, terminate. 14. Glands which correspond to the terminal portion of the oesophagus. 15, 15, 15, 15. Glands which receive all the satellite vessels of the portal vein, and the majority of those which run down from the inferior surface of the liver. anterior surface of the right pillar of the diaphragm to terminate 204 SPECIAL STUDY OF THE LYMPHATICS in one of the glands placed round the origin of the coeliac axis (vide p. 141). The middle trunks, five to seven in number, run towards the inferior vena cava, in company with which they traverse the caval opening in the diaphragm and terminate in the glands situated in the thorax round the terminal segment of this venous trunk (middle and right groups of the diaphragmatic glands) (vide p. 209). The left trunks, which spring from the left extremity of the superior surface, penetrate into the thickness of the left triangular ligament, and are directed towards the oesophagus and terminate in the glands placed round the abdominal segment of this tube ; these glands we have already described with the coronary chain, with which they are continuous. (6) The anterior collecting trunks follow a course diametrically opposite to that of the preceding. They are much less important and rarely exist except in the right lobe. They are directed towards the anterior border of the liver, round which they turn, course along the quadrate lobe and terminate in the superior glands of the hepatic chain (glands of the hilum). (c) The superior or ascending collecting trunks arise from that portion of the superior surface which is near to the insertion of the suspensory ligament. They are the most important of the three groups of the collectors of the superior surface. Within the sus- pensory ligament they exchange numerous anastomoses and ter- minate, according to Sappey, in the following manner : A posterior trunk turns round the posterior border of the liver, and embraces the inferior vena cava, in company with which it enters the thorax and terminates in the glands placed round the intra-thoracic portion of this large venous trunk. An anterior trunk turns round the anterior border of the liver, and in company with the umbilical cord on the inferior surface of the liver, reaches one of the superior glands of the hepatic chain. Many middle trunks " run from below upwards in the suspensory ligament ; these, which may be eight or ten or only three or four in number, unite beneath the diaphragm, forming a very short enormous trunk which traverses the muscle, it then divides almost immediately into two or three branches which terminate in a small group of very small glands situated in front of the pericardium, behind the base of the xiphoid cartilage ; these are the supra-xiphoid glands " (Sappey). 2. COLLECTING TRUNKS OF THE INFERIOR SURFACE. We will study in turn the collecting trunks of the right, the left, the Spigelian and the quadrate lobes. LYMPHATICS OF THE PELVIS AND ABDOMEN 205 (a) The collecting trunks of the right lobe may be divided into posterior, middle and anterior. The posterior collecting trunks, usually two in number, run to the junction of the inferior and pos- terior surfaces ; they are directed transversely inwards, and embrace the inferior vena cava, and terminate in the glands placed round the intra-thoracic segment of this vessel. The middle collecting trunks, which spring from the middle portion of the lobe, run directly inwards towards the hilum and terminate in the superior glands of the satellite chain of the cystic duct and more particularly in the cystic gland. The anterior collecting trunks, smaller but more numerous, run backwards and inwards. Some pass above, and others beneath the gall bladder, and end in the same way as the former. (b) The collecting trunks of the left lobe all terminate in the glands of the hilum and more particularly in the glands of the satellite chain of the hepatic artery. The middle collectors run transversely. The anterior collectors closely accompany the cord of the umbilical vein, the posterior accompany the vein and join their respective terminal glands. (c) The collecting trunks of the Spigelian lobe terminate, some in the glands of the hilum, others in the glands placed round the thoracic segment of the inferior vena cava. (d) The collecting trunks of the quadrate lobe, which are very numerous, but very fine, terminate in the glands of the Mum. The trunks which we have just described on the superior and inferior surfaces of the liver do not collect all the lymphatics which come from the superficial lobules. Some of these lobules send their vessels into the deep collecting trunks. These superficial regions, tributaries of the deep vessels, appear as stellate figures, whose centre corresponds to the origin of the trunk which plunges into the depth of the organ. These figures are especially numerous in the neighbourhood of the two extremities of the liver (4, 4, Fig. 75). II. Deep Collecting Trunks. The deep collecting trunks form two absolutely distinct groups. Some, the descending, are satellites of the portal vein. Others, the ascending, accompany the hepatic veins. 1. The descending collecting trunks run in the thickness of the capsule of Glisson, and thus accompany the branches of the portal vein, the hepatic artery and the biliary passages. For each branch of the portal vein there are usually three or four lymphatic trunks which anastomose with each other. In their course, they unite 206 SPECIAL STUDY OF THE LYMPHATICS one with another and become progressively reduced in number : though their mode of branching does not approach in regularity that of the corresponding blood vessels. On emerging at the hilum, they number from fifteen to eighteen (Sappey). They are often grouped in two distinct bundles which are apparent at the two extremities of the transverse fissure. They terminate in the glands of the hilum. 2. The ascending collecting trunks which were discovered by Sappey in 1850, form round the branches of the hepatic veins a plexiform sheath which is easy to inject. " The larger and smaller trunks which contribute to the formation of this sheath creep along the adherent surface of the venous walls and, like the latter, are directed towards the inferior vena cava. The trunks are reduced to five or six in number on reaching the opening in the diaphragm, through which they pass to empty themselves into the glands situated immediately above " (Sappey). To sum up, the lymphatics of the liver terminate in the following glandular groups: (1) The glands of the hilum. (2) The intra- thoracic glands placed round the terminal segment of the inferior vena cava. (3) The supra-xiphoid glands. (4) The peri-oesophageal glands, which are continuous with the gastric coronary chain group. (5) The glands placed round the coeliac axis. The most important of these glandular groups, as far as the regional glands of the liver are concerned, are the glands of the hilum and the glands placed round the terminal segment of the inferior vena cava ; these latter will be studied later on (vide p. 209). As regards the glands of the hilum, we must be careful to remember that it is very rare to see them arranged in a single bundle, placed transversely, below the transverse fissure. The}* usually form two vertical chains which are more or less continuous, one of which is a satellite of the hepatic artery, and the other of the cystic and common bile-duct (vide Fig. 48 and p. 147). We should note the frequent but not constant presence of one or two glands sometimes of large size, in the depression for the inferior vena cava, in front of this vessel. BIBLIOGRAPHY. Sur les origines, voy. : T. IV, p. 766, et MALL. Proceed- ings of the Assoc. of American Anatomists, 1902. H < <] ' "''-) I Sur 1'anat. macr. : MASCAGNI, loc. cit., tab. XVII et XVIII, ~et~p. 45. SAPPEY, loc. cit., pi. XXXV et XXXVI, et p. 94. Lymphatics of the extra-hepatic biliary passages. The lymphatics of the extra-hepatic biliary passages arise from two networks, LYMPHATICS OF THE PELVIS AND ABDOMEN 207 one mucous, and the other muscular. The collecting trunks which arise from these networks end in the glandular satellite chain which is a satellite of the cystic and common bile-duct. Intimate rela- tions exist between the lymphatics of the terminal segment of the common bile-duct and the lymphatics of the duodenum and head of the pancreas. LYMPHATICS OF THE PANCREAS. The lymphatics of the pancreas arise from a perilobular capillary network which will be described further on (vide 1 vol. iv. p. 830). From this network run numerous collecting trunks which after anastomosing on the surface of the gland, terminate in the peri-pancreatic glandular groups. (1) The greater number of them reach the glands of the splenic chain (vide p. 144). (2) Others end in glands which are satellites of arches formed by the anterior and posterior pancreatico-duodenal arteries. (3) A third group empties itself into the glands placed round the commencement of the superior mesenteric artery. (4) Finally others, which spring from the posterior surface of the pan- creas, terminate, according to Sappey , in the left j uxta-aortic glands ( ? ) Technique. The injection of the lymphatics of the pancreas is very diffi- cult, and it is essential that perfectly fresh subjects should be used. On the other hand, when the injection succeeds, it is usually quite complete. Sappey recommends for choice the pancreas of old subjects. THE LYMPHATICS OF THE SPLEEN. The lymphatics of the spleen, whose mode of origin will be studied further on (vide L vol. iv. p. 867), give origin to two kinds of collecting trunks which are distinguished as superficial and deep. ^^superficial collecting trunks, which were observed by Mascagni, and then by Robin and Legros, are very difficult to inject in man. Sappey even denies their existence. They are, on the contrary, well developed in the ox and horse. In these animals they form a rich network, which is situated between the peritoneum and the fibrous capsule of the spleen. They then run towards the hilum of the spleen and terminate in the same way as the deep collecting trunks. The deep collecting trunks, which are connected to the preceding by numerous anastomoses, are satellites of the blood vessels. In the hilum they are reduced to from six to ten trunks which end in the external glands of the splenic chain ; these glands are placed above the tail of the pancreas in the splenico-pancreatic omen turn. There are usually no glands in the gastro-splenic omentum ; the glands which have been observed here by some authors are probably nothing but accessory spleens, winch are very common in this situation. 1 Treatise of Human Anatomy. Poirior and Charpy. CHAPTER III LYMPHATICS OF THE THORAX WE will study in succession : (1) the different glandular groups of the thorax, (2) the arrangement of the lymphatic vessels of the walls of the thorax, and of the intra-thoracic viscera. 1. GLANDULAR GROUPS OF THE THORAX. The glandular groups of the thorax may be divided into parietal and visceral glands. 1. PARIETAL GLANDS The parietal glands comprise : the diaphragmatic glands, the internal mammary or retro-sternal glands and the intercostal glands. Some of the glands of the axilla belong to the lymphatic apparatus of the thoracic walls, but as it is impossible to subdivide our study of the axillary glands, we will leave aside for the present this thoracic group of axillary glands. DIAPHRAGMATIC GLANDS. Under the name of diaphragmatic glands, we will describe all the glands which lie on the convexity of the diaphragm. They may be divided into three groups : an anterior, a middle and a posterior group. (a) The ANTERIOR GROUP rests upon the anterior fasciculi of the fleshy portion of the diaphragm, in front of the anterior leaflet ofjthe central portion of the diaphragm. It is formed by three distinct masses : viz. a median and two lateral, symmetrically arranged. The median mass comprises two or three glands, placed immedi- ately behind the base of the xiphoid cartilage. These are the supra-xiphoid glands of Sappey. These glands receive their afferents from the superior surface of the liver (vide p. 203 and Fig. 75) : on the other hand, they receive no vessels coming from the diaphragm (Sappey). Their efferents pass into the inferior glands of the internal mammary chain. The lateral masses are formed by two glands, often by a single one. This gland is placed opposite the anterior extremity of 208 L ~~ FIG. 77. Lymphatics of the superior surface of the diaphragm (Sappey). A. Xiphoid cartilage. B, B. Fifth rib. C, C. Sixth rib. D, D. Seventh rib. E. Eighth rib. F. Ninth rib. G. Tenth rib. H. Eleventh rib. K. Twelfth rib. L. L. L, L. Right and left halves of the muscular portion of the diaphragm. M, M. Pillars of the diaphragm. N. Central aponeurotic portion of the diaphragm with i;s three leaflets. 0. Oesophageal opening. P. Opening for inferior vena cava, round which may be seen three and sometimes four glands. Q. Aortic orifice : the aorta has been removed ; the glands which lie on its anterior portion only have been kept. 1. Lymphatic network of the right leaflet of the central portion of the diaphragm. 2. Network of the left leaflet. 3,3. Network situated on the edge of the anterior leaflet; this leaflet being hidden in man by the pericardium which is closely adherent to it, its lym- phatic network can only be injected from the opposite surface. In the human subject- it can only be shown with great difficulty, but in mammals it can be injected with ease. 4, 4, 4. Glands in which some of the small trunks coming from the central portion of the diaphragm end. 5, 5. Two glands situated over the course of the oesophagus, immediately above the oesophageal opening ; they receive the vessels which come from the inner por- tions of the right and left leaflets. 6. Lymphatic trunks which arise from the posterior portion of the right leaflet and right pillar of the diaphragm ; these trunks, three or four in number, terminate in the prae-aortic glands. 7, 7. Lymphatic trunks which come from the posterior portion of the left leaflet and left pillar ; they pass to the same glands as the preceding. 8, 8, 8. Lymphatic networks with close and superposed meshes, which cover the fleshy portion of the diaphragm. 9, 9, 9, 9, 9, 9, 9. Lymphatic trunks which arise from a network on the convex part of the fleshy portion of the muscle, and which then pass towards the lower intercostal spaces and end in the aortic glands. 10, 10, 10, 10. Other smaller networks which run parallel to the muscles which they sur- round ; all of them converge, some running from without inwards, others from within outwards, and terminate in. a small trunk which ends in the plexus of collecting trunks. 11, 11, 11, 11. Plexus of collecting trunks which extends from behind forwards and ter- minates in a large gland situated on the cartilages of the sixth and seventh ribs. 12. Gland in which the plexus of the collecting trunks terminates : this gland is single on the right and double on the left side. 13. Three small glands, situated in front of the pericardium, and to some extent hidden in the surrounding fat ; they receive some lymphatic trunks which traverse first, the suspensory ligament of the liver, and then the fleshy portion of the dia- phragm. From these glands run several trunks which pass into the gla'ids on the right and left of the xiphoid cartilage, over the course of the internal mammary vessels. 14, 14. Glands in which the preceding vessels terminate, and which are continuous with the plexus of the collecting trunks. 209 210 SPECIAL STUDY OF THE LYMPHATICS the osseous portion of the seventh rib. It receives as afferents the anterior lymphatic trunks of the convex surface of the dia- phragm (vide p. 209). Its effe rents, usually two in number, empty themselves into the inferior gland of the internal mammary chain. This gland is always fairly large and is rarely absent (Sappey). (6) The MIDDLE GROUP is formed by two glandular masses, one on the left and the other on the right. On the left, these glands, three to six in number, are always some- what small, and are grouped round the spot where the phrenic nerve approaches the diaphragm. They are placed on the left of the fibrous sac of the pericardium. On the right, their arrangement is slightly differ- ent. Here the glandular mass is of more impor- tance than that of the opposite side, and includes two groups of glands. Some, arranged like the preced- ing, are placed ex- ternal to the peri- cardium, to the right of the in- ferior vena cava, and round the terminal segment of the right phrenic. Others are intra-pericardiac, and correspond to the anterior surface of the inferior vena cava. The middle diaphragmatic glands receive their afferent vessels from the middle portion of the diaphragm. On the right side, they receive in addition numerous lymphatics coming from the liver (vide p. 202). Their efferent vessels pass into the posterior mediastinal glands. FIG. 78. Internal mammary glands, a. Efferent vessel of the internal mammary chain. I, c. Glands of this chain. d. Diaphragmatic gland (lateral mass of the anterior group). LYMPHATICS OF THE THORAX 211 (c) The POSTERIOR GROUP comprises four or five glands deeply situated between the posterior surface of the pillars of the dia- phragm and the anterior surface of the eleventh and twelfth ribs. These glands are usually small and are intermediate between the ab domino-aortic glands and the posterior mediastinal glands. THE INTERNAL MAMMARY GLANDS (Retro-sternal glands ; praesternal glands, Sappey ; sternal glands, Leaf). The internal mammary glands are satellites of the vessels of this name, and form two ascending chains, which run parallel to the lateral borders of the sternum. Their number is very variable. Four to six are usually present on each side. The chain usually commences at the level of the third space. At the level of the fourth or fifth space these glands are almost always absent. Above the fourth rib a single gland is usually found in each space, fairly often two, and much more rarely three. The glands lie upon the internal intercostal muscle in front ; the mammary vessels are usually posterior to them. Behind these vessels, a fine layer of cellular tissue separates the glands from the mediastinal pleura. We may add that the gland in the third space is sometimes hidden by the superior fasciculus of the triangularis sterni. Above the first space, the internal mammary chain, which is always a satellite of the artery, runs like the latter backwards and outwards, then becomes attached to the dome of the pleura arid terminates at the junction of the internal jugular and subclavian veins. Afferent Vessels. The internal mammary glands collect: (1) the efferents of the anterior diaphragmatic glands which themselves receive the lymphatics from the diaphragm and the liver ; (2) the lymphatics from the superior portion of the rectus abdominis muscle ; (3) the lymphatics from the anterior portion of the intercostal spaces ; (4) the lymphatics from the integuments of the praesternal region ; (5) the lymphatics from the mamma (vide pp. 221 and 222). Efferent Vessels. Their efferent vessels usually unite into a single trunk which empties itself into the anterior surface of the junction of the internal jugular and subclavian veins. On the left, this trunk may also terminate in the thoracic duct, and on the right, it frequently terminates in the subclavian trunk. It is more unusual to see it unite with the subclavian and the internal jugular and form a right lymphatic trunk such as our old authors have described (vide p. 291). 212 SPECIAL STUDY OF THE LYMPHATICS INTERCOSTAL GLANDS. These glands are placed in the course of the intercostal vessels, some of them occupy the middle part of the space (lateral glands), and others, the posterior portion (the pos- terior glands). The lateral glands are very inconstant. They are usually placed at the spot where the intercostal artery gives off its perforating lateral branch. They are always very small, and are really nothing but simple interrupting glandular nodules placed over the lymphatic trunks which come from the external intercostal muscles, and are satellites of the vessels and nerves of the intercostal space (vide further on. Lymphatics of the intercostal muscles, p. 224). The posterior glands are much more important than the preceding. They occupy the posterior extremity of the intercostal spaces. They usually correspond to the middle portion of the neck of the rib : more rarely, they are situated over the costo- vertebral articulation. Behind they rest upon the external intercostal muscle, while in front they are covered by the pleura. Their relations with the artery which at this level gives off its dorso- spinal branch are somewhat variable ; most frequently, they lie over it. They receive as afferenis the lymphatic trunks, satellites of the aortic intercostal arteries. The arrangement of their efferent vessels varies at different levels. The efferents of the glands of the four or five lower spaces unite to form a vertical trunk which as it descends increases in size and which terminates in the commence- ment of the thoracic duct. The efferents from the glands above have a transverse or ascending course and empty their contents into the upper portion of the duct. Sometimes several of these trunks unite to form a vertical ascending trunk which terminates in the thoracic duct at a point more or less close to its termination. 2. VISCERAL GLANDS. The visceral glands of the thorax which are very numerous and very important, may be divided into three groups : an anterior group, formed by the glands in the anterior mediastinum ; a middle group, comprising the peritraclieo-broncUal glands, situated at the borders of the anterior and posterior mediastina ; and a posterior group, formed by the glands in the posterior mediastinum. ANTERIOR MEDIASTINAL GLANDS. The glands placed in the anterior mediastinum occupy its upper portion. They are usually arranged in the following manner : They constitute a mass of LYMPHATICS OF THE THORAX 213 from four to six glands situated on the anterior surface of the convex surface of the transverse arch of the aorta. From this prae- and supra-aortic mass, glands detach themselves in chains which run towards the base of the neck. On the right, these glands are grouped, some in front of the right innominate vein, others between this vessel and the innominate artery, others again behind the latter. On the left, we see these glands surrounding the left common carotid, and the left subclavian vessels, some of them being placed in front of the carotid, others between it and the subclavian : finallv, we commonly meet with some of them both on the internal and external surfaces of this vessel. Some authors, agreeing with Barety. describe these glandular chains, which are satellites of the large vascular trunks, as an intra-thoracic prolongation of the deep cervical chains. This mode of description does not represent the real facts, for the chains we have just described are ascending chains which run upwards to- wards the junction of the internal jugular and subclavian, in the same way as the descending cervical chains run towards this same junction. PERITRACHEO-BROXCHIAL GLANDS. The topography of the peritracheo-bronchial glands was minutely studied in 1874 by Barety , whose description still remains classical. Agreeing with this author, we may divide the peritracheo-bronchial glands into four groups, viz. the right and left praetracheo-bronchial glands, and the inter - tracheo-bronchial, and the interbronchial glands. 1. The right praetracheo-bronchial glands are the most important of these groups on account of their number, the constancy of their arrangement and the frequency of the lesions to which they are subject. They are placed in the angle formed by the trachea and the right bronchus. This group usually comprises four or five glands, which normally, are about the size and shape of a large pea or haricot bean. These glands are in relation : in front, with the inferior vena cava ; internally, with the trachea ; externally, with the internal surface of the right lung ; beloiv, with the right bronchus, and the right branch of the pulmonary artery, and the terminal bend of the vena azygos major ; above, this group reaches the subclavian arch, where it enters into relation with the loop of the recurrent laryngeal nerve and the glandular chain which accom- panies it ; finally, behind, it corresponds to the right pneumogastric nerve. 2. The left praetracheo-bronchial glands, which vary from three o 214 SPECIAL STUDY OF THE LYMPHATICS to four in number, are usually smaller than the preceding. They are in relation, in front, with the as- cending portion of the aortic arch ; internally, with the trachea; &e/