/< fo.N.C. jHT3 \'L & < •%UL 1 XrP T f CT 1 Digitized by the Internet Archive in 2016 https://archive.org/details/specialanatomyhi21horn_1 SPECIAL ANATOMY HISTOLOGY. WILLIAM E. HORNER, M. D., PROFESSOR OF ANATOMY IN THE UNIVERSITY OF PENNSYLVANIA — MEMBER OF THE IMPERIAL MEDICO- CHIR UR GIGA L ACADEMY OF ST. PETERSBURG— OF THE AMERICAN PHILOSOPHICAL SOCIETY, &C. Multum adhuc restat operis, multumque restabit, nee ulli nato, post mille sscula praecluditur occasio aliquid adjieiendi. IN TWO VOLUMES. YOL. II. SEVENTH EDITION. WITH NUMEROUS ILLUSTRATIONS. PHILADELPHIA: LEA & BLANCHARD. AND BY 1846 , Entered, according to the Act of Congress, for the year 1846, by William E. Horner, in the Clerk’s Office for, the District Court of the Eastern Dis- trict of Pennsylvania. SPECIAL ANATOMY AND HISTOLOGY. BOOK IV. PART SI. GLANDS — AND THE ORGANS OF ASSIMILATION. CHAPTER I. Prolegomena on the Structure of Glauds. The intimate structure of glands was but imperfectly attended to previously to the celebrated Malpighi, who, in the year 1665, pre- sented to the world his work entitled Exercitationes de Structura Viscerum. Till his time the most minute inquiry had gone but little beyond the point of observation, that glands consisted, as an ultimate arrangement of their particles, in small granular bodies called Acini, from their being clustered like grapes or berries, growing very closely together around a common stem and its branches. The simple idea, propounded by Malpighi, is, that each acinus being a gland of itself, consists of minute spheroidal sacs, which re- ceive the secretion from the blood vessels. Darwin at a much later period modified this idea by advancing that the change occurred in the spheroidal sacs themselves. The celebrated Ruysch having im- proved much the art of injection, was enabled to show in his prepara- tions, that what Malpighi considered as sacs or follicles, were really formed of convoluted blood vessels. He hence adopted the opinion, false in itself, that the substance proper of glands, is formed wholly of blood vessels, and that the minute branches of the latter terminate Vol. II.— 2 6 ORGANS OF DIGESTION. by direct inosculation with the ducts of the glands. As another step in this inquiry, Mascagni and Cruikshank showed that the secreting canals in the mammary glands commence in the form of cells — and Professor Weber has discovered the same feature to exist in the structure of the salivary glands of birds and mammalia, and of the pancreas of birds. The existing state of opinions on this interesting subject, is de- rived from J. Muller, Professor of Anatomy, Berlin, who* has an- nounced as the result of his inquiries on the structure of the secreting canals in all kinds of secreting glands, that such canals are found every where to form an independent system of tubes. “ That whether they be convoluted, as in the kidney and testis, or ramified in an arborescent form, as in the liver and salivary glands — whether they terminate by twig-like cceca, as in the liver — or in grape-like clus- ters of cells, as in the salivary glands, pancreas and mammary glands — their only connexion with the blood vessels in all cases, consists in the latter ramifying and forming a capillary net-work on their walls and in their interstices: and that the finest secreting tubes, namely, those of the liver and kidneys, are always several times larger in diameter than the minute ramifications of the arteries and the veins.” This doctrine is, therefore, a modified resumption of the more ancient one of Malpighi, and claims merely for the entire surface of secreting tubes what Malpighi thought to belong exclusively to their incipient extremities. The leading argument in its favour being, that in every case there is a minute vascular net-work of capillaries discernible on the parietes of these canals, and whose capillaries are much smaller than the secreting tubes themselves. f Glands of the most simple shape are mere recesses or pouches in the thickness of the membrane or surface to which they belong. (. Folliculi .) In some instances they are very superficial and their bottom is reached through a wide orifice — in other instances their mouths are somewhat contracted like the neck of a bottle — in other cases they have a long and tortuous course ( Tubuli ) as the tubuli seminiferi of the testicle. In most of these modifications of a tubular arrangement, from the shortest to the most elongated, the walls of * De Gland. Struct. Penit. Leips. 1830. And Phj'siol. p. 485. London, 1840. j- See Capillaries. ^ GLANDS. 7 the tube are not absolutely uniform, but it will be found that there are either partial or cellular dilatations of it ; or coecal-like appenda- ges, in great numbers discharging into it, and placed in varied an- gular relations to the principal sinus or secreting tube. The stem of a thickly clustering bunch of grapes, the berries being removed, will represent sufficiently well the mere mechanism of this arrange- ment. A form of secreting canal a little more complex is where a large spheroidal dilated sinus exists with tubules, radiating from it [Folliculi aggregati) in lines more or less regular; the sinus itself having a large patulous orifice connecting it, with the surface upon which it discharges. One of the follicles of the tonsil glands may represent this arrangement. Also the glandular linguales on the root of the tongue, which seem to be a mere extension of the lower end of the tonsil gland in the form of an expanded flank, and are not unfre- quently, directly continuous with the tonsil gland. Another form of this composite canalicular arrangement is when the collection of tubules is more in a line, the branches diverging more slightly from each other ( Folliculi compositi ) and each of those branches again diverging into other branches, and so on successively to their last twigs. The Meibomian glands and the vesiculse seminales are in- stances of the linear composite follicle, or tube having but one set of branches. A lactiferous duct is an example of the composite secreting canal, or tube with a numerous and indefinite succession of finer and finer branches, and, -which end finally in club-like dila- tations. Some of these secreting canals end in a divarication of branches resembling the flowering ends of the umbelliferous plants. Some of the glands present a species of regularity in the order of division of their secretory canals. The principal trunk of the latter gives off at intervals nearly uniform lateral branches, these branches give off with regularity other branches, and the latter again observe the same disposition. This modification is preserved to a remarka- ble degree in the pancreas, and is also visible in the salivary glands, the lachrymal, and the mammary. In cases of this kind the lobu- lated condition is very clear, the lobules being rather feebly held in connexion with the contiguous ones by loose cellular substance, allowdng the lobules to be easily separated from each other by drawing at them. The lobules themselves are ultimately divisible into granules, [glomeruli or acini) which under the application of the microscope are found to be aggregated cells, surrounded by a fine s ORGANS OF DIGESTION. vascular net-work of capillaries, and making the peripheral end of the most minute secreting canals. The trachea with its division into bronchia, bronchioles, final air tubules, and air vesicles at the end of the latter, represents on a large scale the division which is seen in glands on a small one. An unsettled question is, whether these vesicular terminations are in all cases kept distinct, or whether from a defect in their parietes they do not communicate like the air vesicles of the lungs, and have in that way a tubule common to several. In some instances the ultimate secretory tubules of those ramified ducts are arranged like cosca around the branches of the latter. Another form of the ramified secreting tube is where there exists no division of the gland into lobules, but it is resolved at once into acini. These acini being formed upon the final divisions of the secretory tube, which rise up in fasciculi, giving a brush like or penicillous appearance. The liver is an example of the above, it being doubtful whether there is any spheroidal enlargement at the free end of the penicilli.* The glands with successively ramified secreting tubes are the Lachrymal gland, Mammary gland, Salivary glands as Parotid, Sublingual, and Submaxillary, Pancreas, Liver. The glands of an almost pure tubular structure and indisposed to ramify, except in a very limited manner, are the Kidneys, Testicles. The Meibomian glands and the Vesiculse seminales may oe con- sidered as a tendency to the same structure, but in a more abbre- viated and simple condition; by some they are considered merely as branched follicles. * From peniculus a painter’s pencil. GLANlDS. 9 The summary of the secretory glandular system then is, for it to present itself in the simple short tubular state of shallow depressions, or crypts of a mucous membrane as in the urethra and bladder; — in bottle-shape cavities; — in closed lenticular cavities, as Peyers’s Glands; — as the follicles of the alimentary canal which are either single or branched; — and as thin follicles with a glandular matter or parenchyma, principally vascular, forming a nidus around them, and which follicles may themselves be either simple or branched in some degree. The principal object of a secreting glandular structure would seem to be a development or augmentation of surface sufficient to the pur- pose of elaborating the quantity of the specific fluid called for ; in other words, for getting area for the requisite ends, like the display of surface in the interior of the lungs for air enough by respiration. The glands seem, therefore, as said by some, to be a sort of efflo- rescence from the surface, or cavity upon which they discharge ; being formed of canals with closed extremities as originally asserted by Malpighi. It is denied by Muller* that there are acini in any glands what- ever (the testes of some few fishes excepted) existing, as commonly understood, to wit ; as solid granules executing secretion, by means of their glomeruli of blood vessels having ducts arising from them, in an unexplained way. On the contrary, he asserts, that acini are merely bundles of fine tubes formed by the ends of secreting canals, or frequently by collections of the vesicular terminations of the latter. The term acinus in its qualified sense is sufficiently proper, but it should be remembered that in receiving it according to its meaning, which is a berry or grape, the skin of the grape and its pedicle are alone to be understood, the pulp being omitted. In regard to the connexion with the blood vesssels, their cavities are as stated according to Muller; not to be considered as continu- ous with the cavities of the secreting tubes, but merely ramified on them by countless capillaries, the arteries simply terminating in the veins as in the case of the lungs, or, I may say, of the intestinal canal. This theory is however, almost too exclusive ; there are most probably organized porosities in the capillary system, I am disposed to think, in the venous especially, forming a communica- tion between the vessels and the canals on which they ramify ; it is * Physiol, p. 501. 2 * 10 ORGANS OF DIGESTION. rather too easy to pass a minute injection from the capillary system into the canal upon which it ramifies, for us to suppose that every such case is one of rupture. We must, also, upon the ground of personal observation to the contrary, decline the opinion of Profes- sor Muller, that there is no communication between the secretory ducts and the lymphatics. The cause of the massive character of many glands and of their shape may now be understood. The shape of glands must depend measurably upon the space and circumstances in which they are ac- commodated; the diversity of shape in the three salivary glands shows that this is a point of merely local convenience, and is subordinate. Their size, however, is upon another ground: this is regulated by the amount of secretion to be done, and by the necessity of this se- cretion being collected at one or more points. The process of as- similation requires the bile in the duodenum, only, and that in large quantity ; hence the liver is both a very large organ and all its secre- tion, is concentrated in one focus. If the necessity for the latter had not existed, the liver like the muciparous glands might have been disposed in small granules all along the alimentary canal. This hypothesis, by the way, will show how the liver or any other gland may exist in the form of insulated acini without the function being altered ; and also show the reverse, how if all the muciparous glands were collected into one mass for the purpose of having a focal point of discharge; that this arrangement would require also a single large duct made by the successive junction of branches, just as in the liver. As the vascular capillaries ramify upon the parietes of the secre- tory tubes, so, their parent branches are found in company with the larger branches of the latter. The development of the tw’o systems is found to be simultaneous. The tubes are first of all planes, then simple canals or coeca, then primary branched canals or coeca, then undergoing an indefinite series of divisions. At first these canals are loose and unconnected, but as the evolution of the gland ad- vances they cohere and become consolidated; but at every period of development and of perfection, the capillaries form a net-W'ork around them smaller than the tubes themselves. There is no essential correspondence between the construction of a gland and its secretion. Very different glands have similar struc- ture, as the testes and the kidneys, and similar glands have a varied secretion in different animals. The liver in one animal is GLANDS. 11 simply in the form of coeca, in another of tufts of cceca ; in others of branches of cells or of a spongy tissue, or as a branched duct having terminal twigs like a feather. The testes are indefinitely varied ; the kidneys alone maintain a constant character. The con- struction of a gland is always regulated by the special demand upon it by the condition of the animal in question; hence the salivary glands are exceedingly simple in birds and serpents ; the pancreas in fish; and the. liver in the lower animals. Where more surface is required, then new processes from the main line of the secreting tube spring up. Recent microscopic observations have ascertained other new points in glandular structure. Purkinje remarked, that the walls of all se- creting cavities or canals are formed by nucleated granules, of the diameter of ys.hav of aline, making, according to his phraseology, the glandular Enchyma , product , or fluid. With the aid of Schwann and Henle this arrangement has been found in all the glands and over the entire mucous surface, constituting in fact a cellular nucleated epithelium, which is now thought to execute the specific secretion of all glands. The determinate physiological doctrine of the day, may be then summed up, in the general declaration, that, whatever be the secre- tion in question, it is elaborated through the growth and nutrition of cells covering the free surface of excretory tubes, and their branches to their very end. So far as the microscope can avail, there appears to be no difference between the structure of the cells of one secre- tion and those of another. Their capacity to eliminate from the blood the specific secretion, is one of those abstruse acts of the sys- tem, depending upon an original endowment ; a dictum in other words, of that creative energy which spoke all things into existence, and still continues to retain them in it. In a case of this kind we may possibly rest contented with the wisdom of a former period. Omnino autem cum JDeus aliquid facit , nulla opus est ratione. Quo- modo nos ex nihilo fecit')* Biliary matter and oil are easily recognised in the above cells of the liver, by their difference of colour, and by their refracting powers: — milk is detected in a similar manner in the mammary gland; seba- ceous matter in the follicles of the skin, and so on of other glands. The above cells having reached a state of maturity, and accom- * St. Joannes Chrysostome. 12 ORGANS OF DIGESTION. plished a perfect secretion within their own cavity so as to fill it, this secretion is discharged by their dehiscence, or dissolution, and is then conveyed to the point where it is wanted. The generation of secreting cells, thus exhausted, is succeeded by another generation, and so the process goes on during the life of the individual. It is thought that in some glands this succession is diffused over the whole free surface of the excretory tubes, but in others that it is confined to the extreme end or terminus.* There are some other organs called glands, but they differ from the preceding in having no excretory ducts. They are supposed to be limited in their function to the modifying in some measure, the fluids going through them. One kind of them is formed essentially of blood vessels, and they are called Ganglia sanguineo-vasculosa ; of these we have the spleen for the chylopoietic system ; the cap- sulce renales for the kidneys ; the thymus and thyroid gland for the organs of respiration, and the placenta for fcetal life. The second kind, called lymphatic glands, (Ganglia lymp/iatico-vasculosa,) con- sist essentially of lymphatic vessels entering on one side and de- parting at the other, after having divided into branches and cells in the thickness of the gland. There are also other glands whose cha- racter and functions are still more doubtful, they being found in con- tiguity with the encephalon, as the Pituitary gland, the Pineal, and the glands of Pacchioni. The real glands on the contrary not only modify the blood which circulates through them, but give rise to a new fluid as a consequence of the transformation of the blood ; and this new fluid is discharged for a specific purpose by its efferent tubes into contiguous canals or places. CHAPTER II. Of the Abdomen Generally. The cavity of the abdomen occupies the space between the infe- rior surface of the diaphragm and the outlet of the pelvis ; a con- Goodsir, see Carpenter Elem. Physiol., p. 409. Phila. 1846. OF THE ABDOMEN. 13 siderable part of it is, therefore, within the periphery of the lower libs above, and of the pelvis below. It is completely separated from the cavity of the thorax by the diaphragm, with the exception of the foramina in the latter, for transmitting the aorta, the ascending cava, and the oesophagus. It is bounded, below, by the iliaci interni, the psose, and the levatores ani muscles ; on the front and sides by the five pairs of muscles called abdominal ; and behind by the lesser muscle of the diaphragm, the quadrati lumborum, the lumbar verte- brae, and the sacrum. The figure of this cavity is, therefore, too ir- regular to admit of a very rigid comparison with any of the common objects of life ; but a little reflection, on the course of its parietes, will make it perfectly understood. It should be borne in mind, that the very great projection of the lumbar vertebrae forms for it a partial vertical septum behind ; which, in thin subjects, is almost in contact with the linea alba in front, and may be easily distin- guished through the parietes of the abdomen, when the intestines are empty. The abdominal cavity varies only, inconsiderably, in its vertical diameter, owing to the resistance of the diaphragm above, and of the pelvis below ; neither does it change behind, owing to the resis- tance of the spine, the ribs, and the muscles there. But as the in- troduction of food, the development of gaseous substances during digestion, the evolution of the foetus, and many other conditions, re- quire some provision for its undergoing an easy augmentation of volume ; the latter occurs principally forwards and laterally, by the yielding of the muscles and by the extension of their aponeuroses. The diaphragm and the abdominal muscles, for the most part, act alternately ; as the former descends in inspiration the latter relax and give way to the contents of the abdomen ; but in expira- tion, the abdominal muscles contract, and the diaphragm is pushed upwards by the viscera. In attempts at the expulsion of feces, and in parturition, these muscles contracting, aud the diaphragm being fixed all at the same moment, the cavity of the abdomen is actually much diminished. The viscera contained in the cavity of the abdomen are of three kinds. One kind is engaged in digestion and assimilation ; another in the secretion and excretion of urine ; and the third in generation. As these viscera are numerous, and it is of great importance to determine wfith precision their position and relative situation, ana- tomists are agreed to divide the cavity of the abdomen into several arbitrary regions. This is the more advantageous, as the bony 14 ORGANS OF DIGESTION. prominences bounding the abdomen are not sufficiently numerous and distinct, to afford those obvious points of relation to the vis- cera which are furnished in other sections of the body. To obtain these regions,* consider a line or plane as extending across the ab- domen, about two inches below the umbilicus, from the superior part of the crista of one ilium, as it appears through the skin, to the corresponding place of the other side. Strike on each side a line perpendicular to the preceding, by commencing at the lower end of the anterior inferior spinous process of the ilium, and car- rying it up to the diaphragm. Extend a fourth line across the ab- domen parallel with the first, and intersecting the last two where they come upon the cartilages of the false ribs. It is evident that these four lines or planes, tw r o horizontal and two vertical, will, with the assistance of the parietes of the abdomen, furnish nine re- gions: three above; three in the middle; and three below. The central region, above, is the Epigastric ; and on its sides are the right and the left Hypochondriac. The central region in the mid- dle, surrounding the navel, is the Umbilical ; and on its sides are the right and the left Lumbar. The central region below, is the Hypogastric ; and on its sides are the right and the left Iliac. There are also some subordinate divisions : for example, the hollow in the epigastric region, around the ensiform cartilage, is called the pit of the stomach, or Scrobiculus Cordis ; and for an inch or two around the symphysis pubis, is the region of the pubes, ( Regio Pubis.) Anatomists differ among themselves about the points of depar- ture and the position of the lines, or rather planes, separating the regions. Some fix them at definite distances from the umbilicus, and others resort to the points of the skeleton. The umbilicus is the most fallacious mark, because its elevation varies considera- bly, according to the state of distention of the abdomen, it being comparatively higher when the abdomen is tumid than when it is not. Neither does it answer to take the anterior ends of the last ribs as the points for the upper horizontal line to pass through ; as they, sometimes, are almost as low r down as the umbilicus itself. The superior anterior spinous processes are also objectionable as the points of departure for the vertical lines ; as they leave too much room for the central regions of the abdomen, and too little for the lateral : I have, therefore, after some hesitation, thought it proper to * Anat. Atlas, Fig-. 297. OF THE ABDOMEN. 15 substitute the anterior inferior spinous processes ; and, especially, as the position of the viscera, according to almost universal descrip- tion, is more in accordance with this rule. General Situation of the Viscera of the Abdomen.* When the abdomen is so opened as to leave its viscera in their natural position, they will be found as follows : — 1. The Liver, the largest gland of the body, is in the right up- per part of the abdomen, immediately below the diaphragm. It occupies nearly the whole of the right hypochondriac region ; the upper half of the epigastric ; and the right superior part of the left hypochondriac. The anterior extremity of the gall-bladder pro- jects beyond its anterior margin. 2. The Spleen is situated in the posterior part of the left hypo- chondriac region. 3. The Stomach, in a moderate condition of distention, occupies the lower half of the epigastric region, and the right inferior portion of the left hypochondriac. 4. The Small Intestine, when moderately distended by flatus, occupies the umbilical region, the hypogastric, portions of the iliac on each side, and also the upper part of the cavity of the pelvis, when the viscera of the latter are empty. 5. The Large Intestine traverses the cavity of the abdomen in such a manner as to perform almost the entire circuit of it. It be- gins in the right iliac region by receiving the lower extremity of the small intestine ; it then ascends through the right lumbar and the right hypochondriac, passes into the lower part of the epigastric, or into the upper of the umbilical, according to the state of distention of the stomach; thence it gets into the left hypochondriac, being fixed higher up there than in the corresponding region of the other side ; afterwards it goes down into the left lumbar and into the left * Anat. Atlas, Figs. 299, 300, 301, 302. 16 ORGANS OF DIGESTION. iliac, where it makes a large long loop, called its sigmoid flexure ; thence it passes into the pelvis, in front of the leftsacro-iliac junction and inclining afterwards to the central point of the sacrum, it sub- sequently descends in front of the sacrum, and coccyx to terminate in the orifice called anus. 6. The Caul, or Omentum, is a membrane, of various densities, in different individuals, and lies in front of the intestines. Some- times it is found spread over the latter like an apron, but on other occasions is drawn up into the umbilical region, forming a ridge across it. It is attached to the stomach and large intestine. 7. The Pancreas lies transversely in the lower back part of the epigastric region. It extends from the left hypochondriac region to the right side of the spine, and is placed behind the stomach, so as to be covered by it. 8. The Kidneys and the Capsulse Renales, each two in number, are placed in the posterior part of the lumbar region on the side of the spine. 9. The Urinary Bladder and the Rectum, in the male occupy th e cavity of the pelvis, and in the female between them are placed the uterus, the ovaries, and the vagina. As, in the dissection of the abdominal viscera, the subject is com- monly placed on its back, so the preceding description is made out with a strict reference to that position. Some modification in the shape of the abdomen, as well as in the situation of its contents, occurs in standing upright. The front of the abdomen becomes then more protuberant, the lumbar vertebrae make a greater projection forwards. The pelvis is also so adjusted, in order to bring the ace- tabula directly in the line of support to the spine, that the convexity of the sacrum presents almost upwards, and the superior strait looks forwards and upwards towards the navel, so that much of the weight of the viscera is thrown upon the pubes. In this attitude most of the viscera descend, but more obviously the liver, from its weight, size, and solidity. Portal has verified this descent by comparing the thrusts of poignards into the liver in the erect, with those inflicted in the horizontal position. He also asserts that the same may be ORGANS OF DIGESTION. 17 Ascertained in the living body by applying the fingers under the false ribs} and then directing the person to change from the recumbent into the vertical position. The spleen affords the same results when it is slightly enlarged, and the descent of the liver and spleen will of Course ensure that of the stomach and intestines. According to Winslow, the pain and faintness which are felt after a long absti- nence, come from the vacuity of the stomach and intestines, which thereby withdraw their support from the liver, and permit it to drag upon the diaphragm. The presence of flatus in the stomach and intestinal canal, seems to be entirely natural to them ; for it is comparatively rare to find them destitute of it, even when they contain no food or feces. The large intestine is, however, more frequently found contracted or empty than the small. Owing to the flexible character of a con- siderable portion of the abdominal parietes, the latter, by their own contraction, as well as by atmospheric pressure, are kept in close contact with the viscera; and the viscera again, by the same influ- ence, are kept in close contact with one another ; so that, notwith- standing the irregularity of their forms and the fluctuating size of the hollow ones, there is no unoccupied space in the cavity of the belly. Several instances are reported by anatomists, in which a total transposition of the abdominal viscera, has occurred, so that those which belonged to the right side were placed in the left.* They are, however, exceedingly rare. In the entire observation of my life, amounting to thirty-five years of anatomical study, and extending itself to many hundred bodies, I have not met with one instance of it. * Portal. Haller. Sandifort., &c. Vol. II.— 3 18 ORGANS OF DIGESTION, CHAPTER III. Of the Peritoneum, and Serous Membranes, Generally. SECT. I. — OF THE PERITONEUM.* The sides of the abdomen are lined, and its viscera are covered by a membrane called Peritoneum. As the reflections of this mem- brane, by being thrown over the periphery of almost every viscus of the abdomen, consequently, assume the same shape; and as it lines, without exception, the interior surface of every part of the abdomen, its form is extremely complicated, and can only be judged of accu- rately after the study of the viscera is completed. For the present it will only be necessary to give the outline of it, leaving the details to each appropriate occasion. In man, it is a complete sac, having no hole in it ; but in woman, its cavity communicates externally through the Fallopian tubes. It has a double use : In consequence of covering the viscera, it is so reflected from them to the sides of the abdomen, that its processes keep the viscera in their proper places, and, therefore, answer as ligaments: again, its internal surface being smooth, indeed, highly polished, and continually lubricated by a thin, albuminous fluid, cor- responding with the synovial membrane of the joints, the motions which the viscera have upon each other in exercise, and in the per- istaltic action of the bowels, are much facilitated. The manner in which a double night-cap is applied to the head, will afford the easiest conception of the reflections of the peritoneum. If there were only one viscus in the belly, and that of a somewhat regular outline, as the spleen, the comparison would be rigid, and perfectly appreciable. One part of the cap is close to the head, and compares with the peritoneal coat of the spleen ; the other is loose, and is equivalent to the peritoneum, where it is in contact with the parietes of the belly. It is also evident from this, that none of the viscera can be said to be within the cavity of the peritoneum ; that they are all on its outside ; and that a viscus, in getting a coat from * Anat. Atlas, Fig. 298. OF THE PERITONEUM. 19 the peritoneum, merely makes a protrusion into its cavity. Start- ing with this simple proposition, it is easy to conceive of a second, a third body, and so on, deriving an external coat from a protrusion into the same sac. Admitting these bodies to be spheres, the pro- position is immediately intelligible ; and, as a last step from it, the idea is not rendered much more complex by substituting any bodies even the most irregular in form, for these spheres. Such, then, is the fact in regard to the stomach, intestines, &c. ; they all, with the exceptions to be stated, derive an external coat from the peritoneum. The Peritoneum is, for the most part, smoothly spread upon the interior surface of the abdominal muscles. It adheres to them with considerable firmness by means of intervening cellular substance: this adhesion, where it closes the posterior opening of the umbilicus, is unusually strong. Below, the uniformity of the membrane as it descends from the navel to the pelvis is interrupted by its being re-^ fleeted over the urachus, and over the remains of the umbilical artery on each side. Where the urachus is, it forms an oblong prominent ridge, reaching to the upper extremity of the bladder ; and, as re- gards each umbilical artery, the duplicature is of a variable breadth in different individuals ; but always forms a well marked falciform process, reaching from near the umbilicus to the lower side of the bladder, and dividing the inguinal region into two parts or fossee, one next to the pubes, and the other near to the ilium. In the un- distended state of the bladder the peritoneum reaches to the pubes, is reflected from the latter to the upper, and then goes over the pos- terior surface of the bladder. In the male, it goes from the posterior lower end of the bladder to the rectum, but, in the female it does not descend so low there, and passes from the bladder to the vagina and uterus, and afterwards to the rectum. In the concavity of the ilium, and in the lumbar region, the peri- toneum is attached by long loose cellular substance, which permits it to be stripped off easily, simply by tearing. In these several re- gions it encounters the colon, over which it is reflected, and thereby forms the Mesocolon; thence it passes in front of the kidneys, but separated from them by a thick layer of cellular and adipose matter, and immediately afterwards it is thrown into a long duplicature, ex- tending obliquely across the lumbar vertebra from above, down- wards, and to the right side. This duplicature includes the small intestine, and is the Mesentery. 20 ORGANS OF DIGESTION. In the highest regions of the abdomen, the peritoneum is in the greater part of its extent uniformly reflected over the concave surface of the diaphragm, and adheres so closely to it, as to require a cau- tious and protracted dissection for its entire removal. As the re- mains of the umbilical vein of the foetus are still found, but in a ligamentous condition, going from the navel to the under surface of the liver, their existence gives rise to the falciform ligament, a broad duplicature of peritoneum, which passes from the upper half of the linea alba and from the middle line of the diaphragm to the liver. Another line of attachment, or of reflection, of this membrane to the liver, is found all along the posterior margin of the latter. In the same region, it is also reflected from the diaphragm to the spleen and to the stomach. Such is the general account of the course of the peritoneum. Each of the duplications has a distinct name, and some peculiarity of organization or of relation, which will require a specific description and a frequent allusion to it. It is proved, from what has been said, that the peritoneum is a single and complete sac, and that, with the exception stated of the Fallopian tubes, there is no hole in it either for the passing of blood vessels, nerves, or viscera. And that it is so folded over the abdo- minal viscera, that with patience and sufficient address, one might remove it from their surface and extract them, without even laying open its cavity : an experiment said to have been successfully ac- complished by Nicholas Massa,* and some other anatomists. SECT. II.— OF THE OMENTA. f There are four processes of the peritoneum, each of which is designated under the term Omentum, Epiploon, or Caul. 1. The Omentum Minus or Hepatico-Gastricum, extends, as its name imports between the liver and the stomach. It begins at the transverse fissure of the liver, proceeds from it, and from the lobulus spigelii, the front of which it conceals; and then continues to arise along the left margin of the base of this lobule to the back part of the liver until it reaches the diaphragm ; it also arises from the inferior face of the tendinous centre of the diaphragm along its posterior * Anat. Liber Introduce an. 1539. Portal, f Anat. Atlas, Fig. 999. OF THE OMENTA. 21 border, by its lower margin; it is attached to the lesser curvature of the stomach in all the space between the cardiac and the pyloric orifice. Its right margin reaches beyond the pylorus to the duo- denum, and includes the vessels going to the liver, and the biliary ducts; in consequence of which, this margin is called the Capsule of Glisson. The capsule is, however, more properly the condensed cellular substance within. The two laminae which compose the omentum minus are thin and transparent, and have but little fat in them; in approaching the stomach they become very distinct from each other, and receive between them the superior coronary vessels of the stomach. One lamina then goes before the stomach and the other behind, in the form of a peritoneal covering. These laminae, having covered in that way the anterior and the posterior surface of the stomach, unite again on the greater curvature of the latter, to form the beginning of the omentum majus. 2. The Omentum Majus or Gastro-Colicum, as indicated by its name, is connected at one end all along the greater curvature of the stomach, and by the other along the transverse part of the colon. As it commences by two laminae, so it is continued throughout in the same way. It is commonly found more or less spread on the front surface of the small intestines, but occasionally it is tucked up in the epigastric region. When fairly spread out, either naturally or artificially, its course will be found as follows: It first of all de- scends from the stomach to the pelvis; it then turns upwards, so as to reverse its course, and continues to ascend till it reaches the colon. Its two laminae then separate and receive the colon between them, so that, in this respect, the arrangement is entirely conforma- ble to what happens to the stomach. The subsequent continuation of these laminae is the mesocolon, which will be more particularly described. As the omentum majus consists of two laminae in its whole extent, it is clear that it resembles a flattened bag lined by another bag; so that in its whole thickness, when held between the fingers, there are four laminae. It is an irregular quadrilateral membrane, which, in corpulent subjects, is interspersed with a great deal of fat; but in such as are emaciated, it is wholly destitute of the latter; and instead of being entire in its parietes is a delicate reticulated membrane, so that the rule about the integrity of the peritoneum is not fully acr 3 * 22 ORGANS OF DIGESTION. curate as applied to this section of it. On the right side it is con- tinuous with the omentum colicum, and on the left with the omentum gastro-splenicum. 3. The Omentum Colicum may be considered as a continuation of the omentum majus along the ascending and a part of the trans- verse colon. In some rare cases, (for in my own observations I have not met with the arrangement,) its origin is continued down- wards to the ececum, and at its left margin is extended along the transverse colon to the spleen. Much more commonly it is, as stated, simply an appendage of the great omentum, or its right flank, advancing for a short distance along the ascending colon. It consists of but two laminae in all, commonly containing fat, but in this respect subject to the same rule as the omentum majus. 4. The Omentum Gastro Splenicum is the left flank or margin of the omentum majus, extended from the great end of the stomach to the spleen. It of course consists of but two laminae, which con- tain between them the splenic vessels and the vasa brevia. By looking for the posterior end of the gall-bladder, and then passing a finger under the right margin of the hepatico-gastric omen- tum, or in other words, under the capsule of Glisson, where it ex- tends from the liver to the duodenum, the finger will be found to have insinuated itself behind the stomach, and, by being directed downwards, will be thrust into the sac or cavity of the great omen- tum. In children, where the latter is less reticulated than in adults, and consequently more entire, a large blow-pipe introduced at the same point will enable one to inflate this cavity, and to separate its anterior from its posterior wall. This aperture, called the foramen of Winslow, is the route by which the internal or lining lamina of the omentum majus is introduced, so as to make this process of peri- toneum double throughout its whole parietes. Though this fact of duplicity is generally conceded, no author heretofore, to my know- ledge, has pointed out satisfactorily the means ; and for the sug- gestion of it, I am indebted to a learned and zealous member of the profession, now Professor Hodge of the University. Struck, at an early period of his studies, with the difficulty of tracing a double sac to the omentum majus, out of a single membrane of the peri- toneum, this suggestion was happily made by him to remove the difficulties of other explanations, An attempt at at diagram formed OF THE OMENTA. 23 upon any other principle I have invariably seen to fail. If the reader has conceived the idea, the inference will be plain, that the lining lamina of the omentum majus is continued as a common peri- toneal covering over the posterior face of the stomach, and then forms the posterior lamina of the hepatico-gastric omentum. It will also be plain that the same lamina, having reached the colon in its re- turn, continues afterwards as the upper lamina of the transverse mesocolon. From wdiat has been said concerning the general qualities of the peritoneum, it is to be understood that though it enjoys much power of gradual extension, nevertheless this quality is not sufficient to enable it to endure, without a special provision, the sudden and extensive dilatations to which the stomach and bowels are ex- posed, from the introduction of food and from the evolution of gases during digestion. Of all the coats of these organs, it is the least extensible and contractile ; its rupture, therefore, is guarded against by one invariable rule. For example : as the muscular and other coats of the stomach dilate, the peritoneum is drawn from the omen- tum minus and majus to cover the stomach ; therefore, as the sto- mach enlarges, the omenta diminish: and as the stomach decreases, the omenta, by the restoration of peritoneum, resume their primi- tive size. In this way the uterus, notwithstanding its great aug- mentation in the progress of pregnancy, still keeps itself covered by peritoneum, from the ability of the latter, as mentioned, to slide from one part and to apply itself to another. The true intention, then, of the apparently useless length of many processes of the peri- toneum, is explained, by their being a provision for the augmenta- tion of the hollow viscera of the abdomen, in the discharge of their natural functions. Adopting this explanation as the basis of our observations, we shall find that according to the probable or even possible augmentation of a viscus, so are its peritoneal attachments. The stomach, which next to the uterus enlarges more than any other viscus, gets its subsidiary supply of peritoneum from the length of the omentum minus and majus ; the colon, which is next in order, is supplied from the length of its mesocolon ; the small intestines, which are next, from the length of the mesentery. The latter, how- ever, would be too long for that simple purpose ; but the objection is removed by recollecting that the mesentery has also to accommo- date numerous chains of lacteal glands, through which the chyle 24 ORGANS OF DIGESTION. must pass in its elaboration, before it is fit to enter into the general circulation. The liver, being of a size almost stationary, has its peritoneal attachments proportionally short ; and its peritoneal co- vering, from the shortness of the connecting cellular substance, is disqualified from sliding. The spleen is in the same predicament with the liver, except that its size is not stationary ; but in this case, the peritoneum presents a phenomenon entirely remarkable : it wrinkles upon the contraction of the spleen. If this mode of reasoning, derived, from an arrangement of parts which no one denies, be correct, it follows that physiologists have erred sadly in the supposed uses of the omentum majus. That this organ is, in fact, only subsidiary to the enlargement of the stomach and colon, so as to prevent the rupture of their peritoneal coat, and that it is neither intended to keep the belly warm, as so learned a naturalist as M. G. Cuvier has suggested,* nor is it a special store-house for the wants of the system during the destitu- tion of other aliment, farther than adipose matter in other parts of the body is.f In regard to the first theory, it does not appear that the inhabitants of cold climates are better furnished with an omen- tum majus than those of the torrid zone: that it is better developed in winter than it is in summer ; that it is tucked up in warm weather to cool the intestines, or spread out in cold weather to make them more comfortable. On the contrary, it is ascertained that its position is variable at all seasons ; that in the coldest of w r eather it is as often found collected in the epigastric region, or to one side of the abdomen, as it is in the warmest ; consequently, its position is the result of whatever motions may, for the time, have been impressed upon it by the distention of the stomach, and by the peristaltic movements of the bowels. In regard to the theory of Dr. Rush, this objection is insurmountable ; that children, who are equal- ly, if not more exposed to starvation and sickness than adults, never have fat, except in very small quantities, in the omentum, and that only along the course of its vessels. The fat is, therefore, not to be viewed as an essential circumstance in the structure of the omentum, as all children and many adults have it only very sparingly ; for the omentum bcimj wanted as a membrane of reserve to the stomach and colon, the deposite of fat in it, is in obedience to one of the * XXII. Le«;on D’Anat. Comp. f An Inquiry into the Uses of the Omentum, by .Tames Rush, Philad. 1809. HISTOLOGY OF SEROUS MEMBRANES. 25 general laws of the system, whereby the cellular substance beneath the serous membranes is disposed to secrete fat as the individual ad- vances in life ; which is exemplified on the heart and in the pleura. Another argument is, that in the ruminating animals, where there are four stomachs, and from the vegetable nature of their aliment these stomachs must, in the course of digestion, be very much distended, the great omentum is of proportionate magnitude.* As occurs in other parts of the body, also, the fat of the omen- tum accumulates in animals that take but little exercise, while it is very deficient in such as lead an active life. There is reason to believe, that the hard knots felt in the abdomen of such persons as suffer from abdominal affections, frequently de- pend upon the accumulations of the omentum majus at particular but variable points. SECT. III. — HISTOLOGY OF THE SEItOUS MEMBRANES. As the peritoneum presents one of the best examples of a nume- rous class of membranes, called Serous, it will be useful at this point to inquire into their general condition and properties. They are, for the most part, thin, and strongly resemble compressed cellular membrane ; having been, indeed, by some anatomists, considered as such. They invariably assume the form of perfect sacs, and as they are found in all parts of the body, they are kept distinct from each other. The arachnoid membrane of the brain, the pericardium, the pleura, the synovial membranes of the joints, the bursae mucosae of tendons, the peritoneum, and the tunica vaginalis testis, belong to this class. They are not all of the same thickness, as some are much more dense than others ; they adhere to neighbouring parts by a lamina of cellular substance, which is also of variable thickness and ductility ; indeed, on some occasions, it is not entirely distinct, from its extreme shortness and tenuity. As the serous membranes are only displayed over the surface of the organs which they cover, after the manner of a double night- cap drawn over the head ; their cavity always remains entire, not- withstanding it is variously modified by the shape of the organs protruded into it ; and has its parietes in contact, owing to external compression. They are entirely distinct from the essential struc- ture of the organs covered, and are displayed over those of the most * Cuvier, XXII. Legon. loc. cit. 26 ORGANS OF DIGESTION. dissimilar functions, as, for example, the intestines and the liver. A sac of this description, then, is of infinite importance in establish- ing between organs which border upon one another a strong par- tition ; and, consequently in warding off any injurious influence which their dissimilar natures would otherwise cause them to have upon each other. Important organs are, therefore, invariably thus insulated, so that whether in a healthy or in a diseased state, their actions are carried on within themselves ; and not only so, but it is even possible, and, indeed, is found in morbid dissections, every day, that an organ may be diseased while its serous covering is unaf- fected ; or the reverse. Thus, we have large suppurations in the liver, while its peritoneal coat is healthy ; large accumulations of water in the tunica vaginalis testis, while the testicle itself is sound ; in the thorax, with sound lungs and heart; in the abdomen, with viscera generally sound ; in the joints, without an affection of the bones. Nothing is more common than to see partial adhesions, the result of inflammation, causing the opposite sides of these sacs to adhere, without any evident constitutional or visceral derangement ; and some of our plans of cure, as in the hydrocele, are founded upon this well established fact. The serous membranes are throughout thin, transparent, and white : in some points their tenuity is so extreme that they seem to consist simply in a smooth, polished surface, spread over parts ; this is strikingly the case on the interior face of the dura mater, on the ventricles of the brain, and on the cartilages of the joints. The evidence of their extension there, is consequently derived principally from induction; and from morbid alteration, in which they become thickened. Their internal surface in a natural state, is always smooth, highly polished, shining ; and, being also lubricated by its peculiar unctuous secretion, the opposite parietes, when they come into contact, glide freely upon each other ; a circumstance indispen- sable to the free action of the joints, and to the peristaltic motion of the bowels. Bordeu has asserted, that these remarkable characters of the serous membranes depend upon the compression and the friction to which they are continually exposed: but to this opinion the argument of Bichat is unanswerable, that in their earliest observable period in the foetus they have the same polish. The fluid secreted from the serous membranes resembles, strongly, tire serosity of the blood. It is poured out continually by the exha- lant orifices, and in a short time afterwards, is taken up by the ab- HISTOLOGY OF SEKOUS MEMBRANES. sorbents ; so that in a natural state there is seldom more than suffi- cient to lubricate the surface of the membrane. When the abdomen of an animal, recently killed, is exposed to the air, this fluid rises in tire form of a vapour. The several experiments, as the application of heat, mineral acids, and so on, which prove the abundarBe of albumen in the serum of the blood, produce the same resultsBhen applied to the secretion from the serous membranes. The system of serous membranes has been considered by Bichat and others, as only a modification of cellular membrane, for the following reasons. The inflation of air into the cellular tissue sub- jacent to them, reduces them to the form of cellular substance. Protracted maceration produces the same effects with more certainty and precision. When cellular membrane is inflated, the parietes of the distended cells resemble strongly the finest parts of the serous system, as the arachnoid membrane. There is an identity of func- tions and of affections, for they are both continually engaged in the great work of exhalation and absorption, and suffer in the same way from dropsical effusion, with the only difference that the latter is more amassed in the one than in the other. My own experience goes to prove, that dropsy very seldom manifests itself, to any extent, in the cellular tissue without also going to the serous cavities, and the re- verse. The serous membranes are also of a uniform texture, like cellular substance; and present no appearance of a fibrous matter. The serous membranes are furnished with a great abundance of exhalant pores, and of absorbents, which carry on their functions with great activity. They, when healthy, receive only the colour- less part of the blood, whence the uniform transparency of these membranes. The existence of exhalant pores, is proved by stran- gulating a piece of intestine with a ligature for thirty-six or forty- eight hours, when they become evident, by dilating themselves so as to receive red blood. A fine coloured injection produces the same result ; and also moistens, by the escape of its watery particles, the surface of the intestine, by a very fine halitus or dew. The intestine of a living animal, if wiped perfectly dry, will, after the same way, soon present another coat of serosity on its surface. The existence of absorbents to a great extent in them, may also be equally well proved, as they very readily receive a mercurial injection, which diffuses itself over their whole surface, and causes them to have the appearance of being formed entirely of such vessels. The readi- ness with which fluid effused into their cavities is taken up, is another / m •28 ORGANS OF DIGESTION. proof of the same. Bichat once saw them distended with air in a man who had become emphysematous from poisoning. Mascagni has frequently found them distended with the fluid of dropsical col- lections, which he recognised by its colour. It happened to the same anatomist to find in two bodies, where there had been an ef- fusion of blood into the thorax, the absorbents of the lungs gorged with blood. This faculty of absorption may sometimes be proved to continue for some hours after death, by keeping an animal in a warm bath. Mascagni asserts, that he has witnessed its continuance for fifteen, thirty, and even for forty-eight hours ; it is not improba- ble, however, that there was some illusion in these instances. In a preparation made by myself of the peritoneal coat of the stomach, pores giving this membrane a cribriform condition are very visible; and Dr. Leidy, to whom I am indebted for a drawing of the same, has the facility of detecting, by the naked eye, similar pores over the whole peritoneum. Whether these pores are exhalant or absorbent, I have not yet ascertained.* They, by their uniformity and smoothness, bear every indication of being organized pores. If a similar arrangement exist every where over the entire extent of serous membranes, it is not an unreasonable conjecture to con- sider them as absorbing orifices, and thus to explain, the high absorbent powers of such membranes. These orifices are most probably formed by meshes of lymphatics; as upon the mucous sur- face of the gastro-intestinal mucous membrane, the Follicles of Lieberkuhn, or the gastro-enteric follicles, are formed by meshes of veins. As serous membranes are also furnished with their Epithe- lium, hence, when it is raised by insufflation, the air does not escape through these pores. It is more than probable that the serous membranes are entirely deprived of red blood vessels ; the latter unquestionably exist, in great numbers, on the exterior surface, where they creep through the cellular substance, but they may be removed with a scalpel without affecting the continuity of these membranes. Again, where these membranes are free and unconnected on both surfaces, as in some parts of the tunica arachnoidea, there is no appearance of red blood vessels. In hernial protrusions, where there is a considerable prolapse of peritoneum, the blood vessels which are found abundantly about the neck of the sac do not follow out the course of the protrusion. Unquestionably some communication exists between the arterial sys- * See Plate, article, Stomach. HISTOLOGY OF SEROUS MEMBRANES. 29 lem and the serous membranes, as proved by exhalation and morbid phenomena, but the mode is not well ascertained. We learn, how- ever, upon the authority of Muller, # that there are some preparations of the peritoneum by Bleuland at Utrecht, — and some also by.Der Kolk, of the same membrane, which prove indubitably that -this membrane contains vessels. In common hernia and in dropsy, the serous membranes become more thick : from my dissections I am inclined to think, that this change is not so great as is generally allowed ; for most frequently, by a careful removal of the exterior cellular substance, they have been restored to their primitive condition. In other cases, as in large umbilical herniae, they are so much attenuated as to be found with difficulty. The power of extension which these membranes possess, is strik- ingly marked in dropsical effusions, in the development of tumours, and in pregnancy ; but much of this apparent quality is derived from their mode of attachment to adjacent parts, whereby they are drawm from one surface to cover another. This happens daily wffiere the peritoneum is drawn from the lowmr part of the abdomen to cover the bladder in the distentions of the latter; in pregnancy, where it is drawn upon the growing uterus from all the neighbouring parts ; and in the distentions of the stomach by food or flatus, where it is drawn up from the omenta. The serous membranes have also a power of contraction equal to that of their extension ; but it should not be confounded with that condition where they are simply restored by the connecting cellular substance, to the surfaces to which they originally belonged. The sensibility of the serous membranes, is extremely obscure in a natural state, and only affords an imperfect sensation of touch. This is proved by the impunity with which they may be irritated on living animals. This has generally been attributed to the want of nerves, which however have been lately traced into the pia mater and arachnoid by Purkinje and Rainy — and into the peritoneum and pleura by Bougery. But, when the condition of inflammation is once established, they feel the most acute and distressing pain. Though they resist most frequently, and for a long time, disease in adjacent parts, yet it not unfrequently is extended to them at last. In such cases, it is generally a local instead of a universal affection, which * Physiol, p. 226 . Vol. II.— 4 V 30 ORGANS OF DIGESTION. is communicated to them : Thus, in the cancer and scirrhus of the uterus; in disease of the spleen, and so on; the portion of perito- neum nearest the affected organ manifests the marks of the disease by meter natural adhesions and by disorganization, without the whole membrane being involved. As the serous system consists in many species of sacs, so each of them has some peculiarity of organization, of attachment, and of vital properties, which is stated elsewhere in the account of the species themselves. By acting on the inner surface of a bivalve shell with dilute acid a very thin pellicle is raised of a structure so uniform and so destitute of organic arrangement that it resembles more the walls of a soap bubble, and it is hence defined as being amorphous or structureless. In some parts of the human body the same exists, in others it is modified by being granular, and in others again by being covered with epithelial scales. This membrane, wherever found, has been desig- nated by Messrs. Bowman and Goodsir as a basement or primary membrane, and is supposed by them to be the matrix of the epithelial scales, which are successively evolved from its free surface, if it does not itself undergo a constant disintegration and renewal. The peri- toneum with all other serous cavities is considered to be lined by such basement membrane in some one of the conditions indicated. The microscope has thus proved that notwithstanding the extremely polished surface of the free side of the serous membranes, yet they are covered by an epithelium, which epithelium has been found on all except the sub-cutaneous bursse. Reichert indeed has described an epithelium upon the interior surface of the tendinous and of the subcutaneous bursse, like that of the arteries and of the true serous membranes.* The epithelium of the serous cavities is, like the epi- dermis, formed of flattened scale-like cells, which are, for the most part, polygonal or tesselated, like a pavement made of hexagonal bricks, and have each a nucleus in their centre. Some of these cells are furnished at their edges with minute hair-like filaments called cilia, which, during life and for some time after death, are in a state of continual whirling or vibration, and as is supposed, for the pur- pose of preventing a stagnation of the fluids in contact with them. These cilia are especially numerous and active in the ventricles of the brain. In some places the epithelium is found without the serous * Muller, Arch. 1844 THE STOMACH. 31 membrane beneath, hence it is inferred that the latter is not so essen- tial as the former in the character of such membranes. These epithelia being always in contact with fluids, they differ from the cuticle by being pliant and humid ; but are restored with equal facility when they are lost by abrasion or inflammation. CHAPTER IV. Of the Chylopoietic Viscera. SECT. I. — OF THE STOMACH.* The Stomach ( Ventriculus , Stomachics ) is a hollow 7 viscus situ- ated in the epigastric region, intended to receive at one end alimen- tary matters from the oesophagus, and to transmit them, at its other extremity, after digestion, into the intestinal tube, where the nutri- tious part of the food is absorbed into the circulation. It is a co- noidal sac, curved considerably upwards, and presents two Faces, two Orifices, two Curvatures, and two Extremities. The Faces of the stomach are, from their position, named ante- rior and posterior, or, one presents to the linea alba and the other towards the spine. The flat configuration is rendered more obvious when the organ is empty ; for when distended it is rounded, and the anterior face is caused to look forwards and upwards from the resistance of the spine behind, while the posterior is of course in an opposite direction. In other respects they do not present any thing worthy of particular attention. f The two Orifices of the stomach are named Cardia and Pylorus. The first or Cardia is at the left and most superior part, but removed to the distance of two inches or more from the left extremity. It is generally considered a smooth uninterrupted continuation of the oesophagus into the stomach, immediately after the oesophagus has passed through the diaphragm into the abdomen. But in a prepara- tion, of this organ, made by drying, J and now in the anatomical * Anat. Atlas, Fig. 303 to 309, inclusive. f In some cases the posterior face of the stomach is concave to accommodate it to the spine . this is best seen on inflation and drying. ^ December, 1828. 32 ORGANS OR DIGESTION. cabinet, a circular rounded pad is very perceptible at the cardiac orifice ; being elevated two lines or more all around, so that it makes a perfect ring of from eight to twelve lines broad at its base. This pad seems to- be composed of a cellular substance, which is almost perfectly white, elastic, and consists of the finest filaments, resem- bling carded cotton : it is placed between the lining membrane of the cardiac orifice and the adjoining coat. The Pylorus, when viewed externally, looks like a smooth con- tinuation of the stomach into the duodenum ; but when felt, there is a manifest thickening of the part, depending upon a structure to be presently explained. It points upwards and to the left side, but is, by the whole thickness of the liver, lower down than the cardia. The two Curvatures are designated the great and small, or the upper and the lower. The first, forming the upper margin of the stomach, is bounded at its extremities by the orifices, and is very concave ; its curvature is maintained both by a natural configuration and by the small omentum. The great curvature forms the whole inferior periphery of the organ, extending also from one orifice to the other. When the stomach is flattened, these curvatures form very evident boundaries to the anterior and the posterior face. The Extremities of this organ are remarkably different in size. That to the left forms the base of the cone, or the large extremity, and projects considerably beyond the cardia towards the spleen. It is a rounded cul-de-sac, or tuberosity, the dimensions of which will, of course, vary according to the state of distention. The right extremity, on the contrary, is produced by a gradual diminution of the organ from its middle to the duodenum. When the stomach has approached within an inch or two of the latter, it suffers a sort of constriction, which gives to the right end a more cylindrical shape. This part is sometimes called the Little cul-de-sac, or the Antrum pylori. When the stomach has been kept empty for some time previous to death, it is found not much larger than an intestine ; its variable magnitude, therefore, prevents any very rigid rule of dimensions from being applied to it ; most commonly, however, we find it be- tween the capaciousness of a pint and of a quart measure. It is retained in its situation by its continuity with the oesophagus and duodenum ; also by the hepatico-gastrio, and the gastro-splenic omentum. It is in contact above, at its lesser curvature, with the THE STOMACH. 33 diaphragm, the left lobe of the liver, and the lobulus Spigelii ; at its great extremity with the spleen, .at its posterior face with the pan- creas, and at its greater curvature, with the colon and the mesocolon. The stomach is formed by four Coats or laminae, of a character essentially differing from each other : The Peritoneal, the Muscular, the Nervous, and the Mucous. The Peritoneal Coat envelops the stomach completely, and ad- heres closely, except at the curvatures, where, as has been men- tioned, a provision is made for the distention of the organ, by the looseness and the separability of the attachment of the two laminae of the omentum minus and of the majus. An uncovered space will, consequently, be found between the laminae at these places, along which the vessels run that furnish the stomach. The peritoneal coat is very thin, and is attached to the subjacent muscular, by very fine cellular substance, which permits it to be raised from the muscular by a careful dissection. In a dried preparation which I made,* there is an exhibition of minute foramina of the peritoneal coat, in apposition nearly as close as the follicles of the mucous coat. Already alluded to in the article on serous membranes, the attending plate, the drawing for which was made by Dr. Leidy from nature, exhibits well the appearance of the piece. The Muscular Coat is intermediate in thick- ness to that of the intestines and of the oeso- phagus, but its fibres are pale, are collected into flattened fasciculi, and go in three direc- tions. The most superficial are a continua- tion of the longitudinal fibres of the oesopha- gus, and are less numerous and less uniform in their distribution than the circular fibres, The greater part of them forms a flattened broad fasciculus, which extends along the lesser curvature of the stomach, from the car- diac to the pyloric orifice. A thinner and less distinct fasciculus may be traced over the great cul-de-sac, and somewhat indistinctly, along Organized pores in Serous coat of Stomach from the 1,40 to the 1,8 of a line in diameter, by nature. the greater curvature : * In 1839. 4 * 34 ORGANS OF DIGESTION. aiul a few others may be seen on the anterior and posterior faces of the stomach forming rather a fine linear or striated appearance than a perfect lamina ; this linear appearance is well exhibited by an oblique reflection of light from it. The second series consists in a lamina of circular fibres distinctly covering the whole surface of the organ. They are not so numerous near the cardia, but become more abundant as they are examined towards the pylorus, in the vicinity of which they are multiplied so as to form a lamina of two lines or more in thickness. The circular fibres are parallel with each other, and, when the stomach is much distended, their fasciculi separate so as to leave interstices between them in many places. The indi- vidual fibres do not surround entirely the stomach, but are rather segments of circles. The third and deepest series of fibres, consti- tuting the muscle of Gavard, from their discoverer, may be called oblique, and are arranged into two broad flattened fasciculi, one of which is placed to the left side of the cardia, and is prolonged over the anterior and the posterior face of the stomach ; while the other, being to the right of the same orifice, is extended over the anterior and the posterior face of the cul-de-sac, where it supplies the want of transverse or circular fibres : this series may be considered as a continuation of the circular fibres of the oesophagus. The Nervous or Cellular Coat ( Tunica Propria ,) connects the muscular with the mucous. It is formed by a compact, thick, and short cellular substance, which when inflated and dried, looks like carded cotton. It contributes much to the general strength of the organ, and serves to conduct the blood vessels and the nerves to the mucous coat. The Mucous or Villous Coat is the most internal, is not quite a line in thickness, and can be readily raised up by dissection. In an undistended state of the stomach it is arranged into a number of wrinkles, which are very irregular in their form, size, and direction, but disappear immediately on distention, or at least leave but very faint traces. It is continuous with the internal membrane of the (esophagus and duodenum, but presents a surface differing from either of them, and which is rendered very apparent by floating it in water. The epidermis, which is continued along the internal face of the oesophagus, ceases as mentioned around the cardiac ori- fice, and, by a slight maceration maybe raised up and demonstrated THE STOMACH. 35 to terminate there. An epithelium under modified circumstances is then found to start and to cover the entire interior of the stomach, and to be continued over the intestinal canal from one end to the other. It is softer, thinner, and more spongy than the common epidermis of the pharynx and oesophagus, but may be proved to exist by the microscope, by the exfoliations in scales found in the feces, and also by insufflation, when it will be raised and may be dried in that state. This mucous membrane or coat, the office of which is to secrete the gastric juice for the digestion of articles of food, presents a sur- face that resembles very much common velvet, from whence the term villous is applied to it. If it be perfectly healthy, and the individual died suddenly a few hours after eating' — -it is found of a uniform light pink colour, without blotches or anything of extravasation under it. This fact I have had several opportunities of verifying, by experi- ment and by autopsies :* And more lately in the person of a crimi- nal, Williams, executed for murder. f It is usual, to find it, if ex- amined a short time after death, having, particularly along the smaller curvature and at the great end, a pink and sometimes a deeper colour, produced by an accumulation of blood in its veins. The texture of this membrane is soft, loose, and easily lacerated. When floated in water and examined with a magnifying glass, it is found to have a superficial honey-comb arrangement, and to be studded with a multitude of small follicles or orifices whose number is above fourteen thousand to the square inch, and whose diameter varies from the fortieth to the eighth of a line. In the vicinity of the cardiac and of the pyloric orifice, the same arrangement is more ob- vious, and exhibits also some small glands, which are more or less apparent, and called the glands of Brunner, being by some con- sidered muciparous and by others as the source of the gastric fluid. £ At the junction of the lesser extremity of the stomach with the duodenum, the internal membrane is thrown into a circular dupli- cature constituting the Pyloric valve, and abridging the size of the orifice. It is seen most favourably in the distended and dried state, and then presents a sort of septum not unlike the form of the iris. Around the external periphery of this ring, the circular muscular fibres have an abrupt augmentation of number, which gives them, * See Amer. Journal Med. Sciences, Yol. i. 1827. Horner’s Pathol. Anat» p. 195, &c. f Aug. 9, 1839. \ Anat. Atlas, Fig. 311.. 36 ORGANS OF DIGESTION. when viewed from the duodenum, the appearance of a distinct cir- cular muscle, occasionally called the muscle of the pylorus, but it does not exist in a state so separate as this name indicates. The opening of the pyloric valve is generally circular, but sometimes ovoidal, and it is sometimes to one side. It is very common to find the stomach divided as it were into two compartments, by a contraction of its middle, resembling that of an hour glass. It is said that this occurs habitually during diges- tion ; in my personal observations, however, I have seen the stomach more frequently in this state when it contained nothing, not even air, than when articles of aliment were in it. The stomach is extremely vascular. Its arteries, being branches of the Cceliac ; are the Gastric, the Right, and the Left Gastro- Epiploic, and the Vasa Brevia. The first goes along its lesser curvature, the second and the third along its greater curvature, and the last, from four to six in number, go to its great cul-de-sac. They all approach it between the laminae of its omenta, and undergo many divisions and subdivisions in the cellular coat; they at length termi- nate by forming a very fine and delicate vascular arrangement in the substance of the mucous membrane, and when success- fully injected give to the latter a thorough tinge of red. The veins follow the course of the arteries, and like them have frequent anastomoses, but are larger ; they terminate either directly or indirectly in the trunk of the Vena Portarum. The attending plate drawn by Dr. Leidy from an injection of mine, exhibits the veins of the stomach as seen with a microscope, on the mucous coat. The nerves of the stomach come from the Par Vagum, and from the semi-lunar ganglions of the Sympathetics. Its lymphatics arise from both the external and the internal sur- face, and their trunks having to pass first of all to the lymphatic glands situated along the curvatures, afterwards empty into the tho- racic duct. Fig. 22. Reticular arrangement of veins to form the mouths of the mucous follicles of the stomach. Natural dia- meter of meshes from the 1-40 to the 1-8 of a 4-ine in diameter. INTESTINAL CANAL. 37 SECT. II. — OF THE INTESTINAL CANAL. The Intestinal Canal is from thirty to thirty-five feet in length, and extends from the pylorus to the anus. Owing principally to a well marked difference in magnitude, it is divided by anatomists into the Small and into the Large intestine. Of the Small Intestine * The Small Intestine ( Intestinum Tenue) commences at the pylorus, and terminates in the right iliac region by a lateral aperture into the large intestine. It is four-fifths of the length of the whole canal, and measures from twenty-four to twenty-eight feet. 7 When mo- derately distended its diameter is about one inch. It retains from one end to the other an uninterrupted cylindrical shape, with the exception that if the two ends be compared, the upper will be found larger than what is stated as the medium measurement, and the lower smaller; by which arrangementit occurs that the intestine de- creases successively from above downwards; and, as a whole, is slightly conoidal or spindle shape, though this diminution is so gradual that it is not perceptible in any short space. The small Intestine, like the stomach, consists of four distinct coats, the peritoneal, the muscular, the cellular, and mucous. The Peritoneal Coat is complete, and forms the external surface. It is continued afterwards in two laminae from the intestine to the lumbar vertebrae, thereby constituting the Mesentery. The two laminae, where they depart from the intestine, are loosely connected with each other, for the purpose of allowing room for the dilatation of the intestine, on the same principle which is exemplified in regard to the stomach. * Anat. Atlas, Figs. 313 to 324, inclusive. f This is the generally received opinion of anatomists : it would appear, however, to be applicable only when the intestine is left attached to the me- sentery; for if it be cut off and straightened, it will measure thirty-four feet, which, added to eight feet of large intestine treated in the same way, will amount in all to forty-two feet. If to the estimate of this length we add what is lost by the doublings of the mucous coat, the entire length of surface must amount to nearly sixty feet ; at least, in many subjects. 38 ORGANS OF DIGESTION. The Muscular Coat is next to the peritoneal. Its fibres are pale, and form a lamina not so thick as common writing paper. The superficial ones are longitudinal, not very distinct, and too much separated to form a perfect coat: they are most abundant on the anterior semicircumference or the one most distant from the Mesen- tery. The others all run in a circular direction, approaching to the spiral, and are sufficiently numerous to form a perfect coat: none of them perform a complete circuit of the intestine, but are rather segments of circles. This coat is united to the peritoneal by a thin scattered cellular substance. The Cellular Coat of the small intestine, ( Tunica propria) also called the Nervous, like that of the stomach, is only a lamina of dense cellular substance, which serves as a medium of connexion between the muscular and the mucous coat: and also conducts to the latter the blood vessels, nerves, and lacteals. When inflated and dried, it puts on a beautiful cotton-like appearance — just as the corresponding coat of other parts of the alimentary canal does under the same treatment. In the lion this membrane presents a most elegant clear tendi- nous appearance, and is so strong that it will bear, from the interior, the pressure of a column of water eighteen feet high. The mus- cular and peritoneal coats splitting open, while it remains entire. Under this strong pressure of water neither the lacteals nor blood vessels are filled with it, which goes to prove that the introduction of articles into them, from the intestinal cavity, is a vital and not a physical action. The Mucous Coat is the most internal, and when it has been cleaned by maceration, exhibits an 'opaque pearly colour. It is remarkable for having its extent very considerably augmented beyond that of the other coats, by being thrown into a great number of permanent folds, or duplicatures; which lie one upon another successively, like the shingles upon the roof of a bouse. These duplicatures are the Valvulse Conniventes, and are for the most part about three lines in breadth. They are either placed in the direc- tion of the circumference of the intestine, or are very slightly ob- lique ; generally they go all around, but many of them are segments of circles, and by being arranged successively, their ends pass one another, or are connected by slight elevations. They are more INTESTINAL CANAL. 39 numerous and broad in the upper than in the lower half of the in- testinum tenue, and are evidently intended to retard the progress downwards of alimentary matter, and to increase the surface for absorption and for exhalation. The mucous membrane, on the side which it presents to the cavity of the intestine, is furnished with a great number of delicate cylin- drical projections, resembling the down on the skin of an unripe peach, and called Villi,* * * § from whence the term villous has also been applied to this coat. These villi are to be found in abundance every- where ; but in the upper half of the intestinum tenue they are so numerous as to stud its whole surface, and to be in contact with each other. They are from one-fourth of, to a line in length; and some of them, when examined with a microscope, appear flattened and fungiform. According to the estimate of Meckel, f where they are thickest, every square inch of intestine furnishes about four thousand of them, and by extending this computation, with a proper allowance for diminished numbers below, their aggregate amount is about one million 4 Each Villus is composed of an artery, a vein, and a lacteal ab- sorbent; all united by cellular substance. § From the extreme vas- cularity of the mucous membrane, the blood vessels readily receive a fine injection and thereby become evident, forming a very delicate vascular net- work in each of the villi. It is generally believed, that the absorbent opens on its surface, but whether by one or more orifices is yet unsettled. According to the celebrated Lieberkuhn, there is commonly but one orifice at the end of each villus, and very rarely two: this assertion he considered himself as having esta- blished by passing a current of air through the villus till it was dried, and then slitting it open. Hewson, Cruikshank, and W. Hunter, on the contrary, are said to have found many more, amounting even to twenty, on such villi as were gorged with chyle. The subject has been fruitful in controversy to anatomists, and ranks many dis- * This is intended merely as an expression of the common and received notion, my own views are exhibited in the minute anatomy of this coat. — Sect. hi. f Manuel d’Anat. X Aids i s probably much below their real number; in an observation at the University we have found the villi on the ileum at its lower part amounting to six thousand four hundred to the square inch, but as their shape varies very much, as we shall see ; a rule cannot be derived from their shape. § Anat. Atlas, Figs. 310 — 312. 40 ORGANS OF DIGESTION. tinguished champions on each side ; but from the minuteness of the parts under discussion, it is exposed to much fallacy and illusion ; and is not as yet fully settled. The more important fact, however, is conceded by the admission of all, that there is a branch of the absorbent system in every villus; and which has, for its function, the absorption of chyle from the cavity of the intestine. A more recent observation has been made by Professor Krause,* in the body of a young man who had been* hung after taking a full meal, he found the villi of the jejunum beautifully filled with chyle. 'Fhe lacteal of each villosity arose by several branches, of which some terminated by a free extremity, and others by anastomosis with each other. Judging from his plate, he does not appearto have traced any branch to the surface of the villus. Muller says, that he himself had never seen any opening at the extremity of the villi. This corresponds with my own experience, as I have, also, in one case, had a fine op- portunity of seeing them distended with chyle. The villi, however, under any circumstances, cannot be considered as the sole organs for the absorption of chyle, for in many animals they do not exist. f A more calm inquiry into this matter will, probably, bring us all to the conclusion, that the villi exercise a tactile more than an absorb- ing power, which office their strong analogy with the papillae of the cutis vera strongly points out. An abundance of Mucous Glands is found deposited in the cel- lular coat of the small intestine, between the muscular and the vil- lous ; their ducts open upon the internal surface of the latter, in the interstices of the villi, and from their smallness require the intestine to be floated in water, and examined with a magnifying glass, before they can be recognised. In order to see the glands themselves, the intestine must be cleaned by soaking it in water; it is then to be slit open longitudinally, and held between the eye and the light, in which case the glands appear like little points or spots in the thick- ness of the intestine. They are more abundant in the beginning of the latter, decrease about its middle, and increase again towards its termination. Their structure is very simple, as they consist in a congeries of blood vessels, terminating in short canals secreting mucus. ij: Some of these glands are microscopical, and are called cryptic : * Muller’s Archives, 1837. f Muller, Physiol, pp. 287, 288. \ Soemmering-, de Corp. Hum. Fabrica. INTESTINAL CANAL. 41 they appear as extremely fine cul-de-sacs, or blind pouches, made by inflections simply of the mucous coat, and are at the rate of near twenty-five thousand to the square inch, with a diameter varying from about the fortieth to the twentieth of a line. Other glands are to be found from that size to a line in diameter, and flattened. . They are either alone or in clusters. The solitary ones ( Glandules Soli- taries, Brunneri ,) are found principally about the duodenum and the neighbouring portion of the small intestine, but also exist all the way down in a scattered manner. The others ( Glandules Agminatce , Peysri ,) exist principally in the lower part of the small intestine, and are collected into clusters varying from a few lines to three or four inches in length, but seldom more than from eight to twelve lines broad. They are, for the most part, in elliptical patches, which, in a healthy state, may be recognised rather by a slight discoloration, than by the more ordinary means, and are generally situated some distance from the mesentery. There are about thirty of these clus- ters, of all sizes, in the ileum, and they are placed nearer and nearer to one another, in approaching the ileo-colic junction. All of these glands of Peyer are too much flattened to project sensibly into the cavity of the intestine, and, when they do, there is reason to believe that they are in a diseased state, at least in the adult. For the most part, in children, the glands of Brunner may be seen without diffi- culty, in the whole length of the small intestine, and in adults some are found to project like little hemispherical grains at wide intervals apart into the duodenum. The mucous coat of the small intestine is every where extremely vascular. The Small Intestine, though an uninterrupted tube from one end to the other, is divided by anatomists into Duodenum, Jejunum, and Ileum. There is some reason for the first name, but the two latter may be very conveniently blended, as has been done by some, under the term Mesenteric Portion of the intestinal canal. The Duodenum, named from its being about twelve inches, or twelve fingers’ breadth in length, is nearest to the stomach, and is the commencement of the canal. It is considerably larger than either of the others, and is, moreover, susceptible of great dilatation, whence it has also been called Ventriculus Succenturiatus. Its di- rection is much varied ; beginning at the pylorus, it first of all passes Vol. II.— 5 42 ORGANS OF DIGESTION. upwards and to the right side till it reaches the neck of the gall- bladder ; it then turns downwards, so as to form a right angle with itself, and descends in front of the right kidney to the third lumbar vertebra, being there placed behind the superior lamina of the trans- verse mesocolon. It then forms a round elbow, crosses the spine obliquely, under the junction of the mesentery and mesocolon, in ascending from right to left ; and making its appearance to the left of the second lumbar vertebra, is there continued into the mesenteric portion of intestine. The beginning of the duodenum is moveable, and has a peritoneal coat continued from the lesser omentum ; the descending and the transverse portions have no proper peritoneal coat, but are only loosely fixed between the laminae of the mesocolon ; the termination of the duodenum is both moveable and has a peritoneal covering, from being at the commencement of the mesentery. From the course assigned to the duodenum, it is evident that it forms the segment of a circle, the concavity of which looks to the left side. This concavity is occupied by the head of the pancreas. The transverse portion crosses the spine below the pancreas, and is separated from it by the superior mesenteric artery and by the vena portarum : behind it are the crura of the diaphragm, the ascending cava, and the aorta. The organization of the duodenum is the same with that of other portions of the intestinum tenue. Its peculiarities consist only in a partial deficiency of peritoneal coat, and in its augmented size. Its internal or mucous coat is very much tinged with bile, abounds invalvulae conniventes, especially in its inferior three-fourths, and about four inches from the pylorus is marked by a small tubercle or elevation indicative of the common orifice of the biliary and pan- creatic ducts. The Glands of Brunn, commonly called of Brunner, are very conspicuous in this intestine on raising its mucous coat, and are so numerous near the pyloric orifice, as to form with some a perfect layer, and to give it a granulated appearance for two inches or more. These glands originally called the Secondary Pancreas by Brunn, are also considered by Mr. Cruveilhier and Boehm to be pancreatic in their structure. This idea was first inculcated by their discoverer,* who considered them to secrete a peculiar liquor, * .1. Conrad, A. Brunn, Gland. Duodeni Seu Pancreat. Secund. Descriptio Anat., for which treatise in full see Mangetus, Theatr. Anat. t. i. p. 276. Geneva, 1716. The other glands of Brunner found all the way down the small INTESTINAL CANAL. 43 but thought that the action of the pancreas if it were exterminated would easily pass to them,* hence his appellation to them of Pancreas Secundarius. The Jejunum and Ileum form the remaining length of the small intestine, and have no external marks of difference from each other. They are strung along the mesentery, and, in consequence of their great length, are thrown into folds or convolutions, which give to them a complicated appearance. There is, however, no difficulty in tracing them regularly from one end to the other. They occupy the umbilical, the hypogastric, and a part of the iliac regions, and are surrounded by the circuit of the colon. The upper two-fifths is the jejunum, and the lower three-fifths, the ileum. This distinction, originally introduced by Galen, f from a supposition that the jeju- num was more frequently found empty than any other intestine, has no rigid anatomical support. The only difference between the two is, that the valvulae conniventes, existing as they do in the whole length of the jejunum, become less abundant at the upper part of the ileum, and finally disappear entirely towards its lower extremity. They decrease indeed very sensibly at the lower part of the jeju- num, and sometimes there are none at all in the ileum. In an ob- servation made carefully on this matter by detaching the intestine from the mesentery — inverting it and then measuring, I found the valvulae conniventes to cease as near as may be, in the middle of the length of the mesenteric portion of the intestinal canal. The above distinction into jejunum and ileum has been rejected by the most approved modern authorities, such as Haller, Soemmering, and Meckel. It sometimes happens, that the intestinum tenue has one or more blind pouches like caeca appended to its sides and opening into its cavity. The small intestine is supplied with blood from the superior me- senteric artery. Its nerves come from the sympathetic. The Mesentery ( Mesenterium ) is a process of peritoneum which serves, as mentioned, to connect the intestinum tenue to the poste- rior parietes of the abdomen, and extends its connexions from the left side of the second lumbar vertebra to the right iliac fossa. This attachment, called the root, is about six inches in length ; whereas,. intestine, are evidently different from these in being more spherical, always solitary, and small in comparison. * Id. p. 291. f Portal, Anat. Med. 44 ORGANS OF DIGESTION. its lower circumference, which encloses the small intestine by giving it a peritoneal coat, is, of course, the whole length of the bowel, (duodenum excepted,) and, consequently, from twenty-three to twenty-seven feet in length. This expansion becomes intelligible the moment that the arrangement of the part is inspected, and is somewhat after the manner of a ruffle, except that it is not puckered at the root. The two laminae of peritoneum which form the mesentery, con- tain between them the superior mesenteric artery, and the correspond- ing portion of the superior mesenteric vein ; an abundance of lym- phatic or lacteal glands and vessels ; ramifications from the solar plexus of the sympathetic nerves ; and a considerable quantity of cellular and of adipose tissue. The superior lamina is continued directly into the mesocolon, and at the place of junction the trans- verse part of the duodenum is very perceptible beneath. The lower lamina descends along the posterior parietes of the abdomen, con- cealing the large blood vessels there, and the ureters. Of the Large Intestine* The Large Intestine ( Intestinum Crassum ) receives the effete matter from the small, and is supposed also to make some peculiar secretion of faecal matter from its internal surface. It exceeds much in its diameter the small intestine, and differs also from it in not being by any means so nearly cylindrical. It commences at the in- ferior end of the small intestine, and terminates at the anus, de- scribing in this course, as mentioned, a circle which surrounds two- thirds of the abdomen, and embraces the intestinum tenue. Like the latter, though only a continuous tube, it is divided into three parts ; the commencement of it, which is below the insertion of the ileum, and about two inches in length, is the Coecum, or Caput Coli ; the remaining portion, which occupies almost its whole length, is ealled the Colon, until it reaches the brim of the pelvis, when the name is converted into Rectum. The Mesocolon is a reflection or duplication of peritoneum, that fixes the large intestine to the posterior parietes of the abdomen. Anat. Atlas, Figs. 325 to 331, inclusive. INTESTINAL CANAL. 45 This duplicating is not of a breadth so uniform as the mesentery, but allows to the middle of the large intestine very considerable motion, up and down, according to the distention of the stomach, while the lateral portions are very much confined. For instance, in the right iliac fossa the mesocolon is so short that the posterior sur- face of the gut is in contact with the iliac fascia, and adheres to it by loose cellular substance ; and in the right and left lumbar regions tire bowel is immoveably fixed in front of the kidneys near their outer margin : but in the space between these two points, that is to say, where the bowel traverses the hypochondriac and the epigastric or umbilical region, the peritoneal attachment, here called, from its situation, the transverse mesocolon, is so long and so loose that it forms a complete and moveable septum between the small intestine and the stomach. In the left iliac region, again, the large intestine, after having been bound down to the left lumbar, is suddenly loosened by an increased breadth of the mesocolon, which permits it to form a large convolution, called its sigmoid flexure. The me- socolon is then continued into the pelvis in front of the sacrum, first of all a little to the left of the middle line of the latter, and, as it de- scends it gets directly in front of the middle line. The portion of it in the pelvis is called mesorectum, from the gut which it serves to attach. The composition of the mesocolon is precisely the same with that of the mesentery, though it be not so thick : it, therefore, consists in two laminae of peritoneum, which contain between them some adipose and cellular matter, along with the arteries, the veins, the nerves, and the absorbent vessels and glands belonging to the large- intestine. When the large intestine is inflated, it is rendered very obvious that it decreases in size from its commencement to the lower part of the sigmoid flexure, it then increases again in size just above the anus. Its surface is arranged into three series or longitudinal rows of projections, separated by transverse depressions, the whole cor- responding with an internal cellular arrangement, by the latter sur- face being the reverse of the former. Its coats, like the small intestine, are four in number; the perito- neal, the muscular, the cellular, and the mucous. The Peritoneal Coat prevails in its whole extent, with the ex- 5 * 46 ORGANS OF DIGESTION. ception of the lower part of the rectum : on the ascending and the descending portions of the colon, however, where the latter comes in contact with the parietes of the abdomen, the peritoneum does not invest it entirely ; but the transverse portion or the arch, as it is called, and the sigmoid flexure, are completely surrounded. The surface of this intestine is studded with small projections of various lengths, called Appendices Epiploicae, which are small du- plicatures of the peritoneal coat containing fat. The Muscular Coat is thin, and like that of the small intestine, consists of two orders of fibres, the longitudinal, and the transverse or circular. The longitudinal fibres have the peculiarity of being collected into three equidistant, flattened fasciculi or bands, of about half an inch in breadth, which begin by a common point at the extremity of the cceeum, and extend to the upper end of the r ectum. One of them is along the line of junction with the mesocolon, another anterior, and the third inferior. These fibres, being shorter than the other coats of the gut, have the effect of puckering them into the internal cellular condition alluded to ; for,, when they are cut through, the intestine is much elongated, and its cells disappear. It occasionally happens that the longitudinal fibres, instead of being confined to the bands mentioned, exist in considerable quantity over the intermediate spaces; in this case the cellular arrangement is not so complete, and in some instances is entirely dispensed with ; of the latter, an example is in the Anatomical Museum. The circular muscular fibres form a thin semi-transparent lamina beneath the last, and do not present any peculiarity of interest, they make a thicker layer than exists in the small intestine. The Cellular Coat, or Tunica Propria, is a thin lamina of dense cellular substance, serving to connect the muscular with the mucous coat, and to conduct the blood vessels and nerves to their termina- tions on the latter. The Mucous Coat lines smoothly the internal face of the cellular, and has no doublings or folds, exclusively in it, like the valvulce conniventes of the small intestine.* The transverse projections ♦This may be considered as the general rule: if the gut be examined, however, in its whole length, here and there narrow folds may be found in some subjects. INTESTINAL CANAL. 47 which it makes between the longitudinal bands, into the cavity of the gut, and which separate the cells of the large intestine from each other, are not mere duplicatures of it alone, but are also constituted by the other coats. Near its commencement this coat has the fungous appearance of the stomach, but about the sigmoid flexure it has a plain, smooth, and, to a degree, a polished surface. It has but few villi, such as exist in the small intestine ; indeed, some anatomists deny that it has any, and I have not myself seen them after repeated and care- ful examinations. Its muciparous glands are numerous, and, when somewhat enlarged, project; they are very conspicuous about the sigmoid flexure, and in the rectum. The enteric follicles exist in this large intestine strikingly, as they do in the mucous coat of the sto- mach and small intestine. Their number, on an average, is about twenty thousand to the square inch, with a diameter varying from about the fortieth to the twentieth of a line. When examined with a microscope they make this mucous membrane, owing to its smooth- ness, look like a riddle. The lacteals are not abundant. The mucous coat of the large intestine is very vascular, but not so much so as that of the small intestine. Each division of the large intestine has some peculiarities of structure and connexions ; which may now be attended to. The Coecum, or Caput Coli, is generally from an inch and a half to two inches long, has a rounded termination below and somewhat to the left, from which proceeds an intestinal process, the Appendicula Vermiformis. The latter is from three to four inches long, is cylindrical, has a diameter of two or three lines, and consists of the same number of coats, having the same structure with other portions of the intestinal canal ; its base is the place from which the three longitudinal bands start. It is attached to a narrow duplicature of peritoneum, a process of the mesentery, which per- mits it to float loosely in the abdomen. It seldom contains faeces, but is kept distended by flatus. The ccecum, as mentioned, is, for the most part, confined to the right iliac fossa, but we very frequently see it with a length of peri- toneal attachment permitting it to descend for a short distance into the lesser pelvis. The Ileo-colic Valve ( Valvula Bauhini ) is formed at the junction of the ileum with the caput coli. This valve, destined to prevent 48 ORGANS OF DIGESTION. the return of fa 1 cal matter from the large into the small intestine, con- sists in a transverse elliptical opening, or slit, whose two lips become approximated in the distentions of the colon. The ileum runs into the left wall of the large intestine, and continues its cellular and mucous coats into the corresponding coats of the latter. The cir- cular fibres of the large intestine separate to a certain degree to permit this introduction, but their farther separation is restrained at each commissure or corner of the lips, by a blending of the structure, aided by a few ligamentous fibres, designated as the retinacula of Bauhin or of Morgagni; which, however, are frequently not very distinct. This separation is also restrained by the two longitudinal bands between which the lips are placed, one of which bands is at the posterior commissure, and the other only a short distance from the anterior. The lips themselves, formed principally by the mucous membrane, approach one another after the manner of the ship dock or canal gate ; the superior is somewhat broader than the inferior. Their power, as well as their existence, depends entirely on the tension which is kept up by the natural connexions of the parts ; for a very slight dissection causes them to become almost effaced, and instead of forming an elliptical transverse opening, to be converted into a round patulous one. The Colon, properly speaking, has some regional distinctions which are serviceable to accurate description. The right lumbar colon, which is bordered in front by the small intestine, and behind, by the right kidney, extends from the ileo-colic valve, to the margin of the false ribs of the corresponding side. The transverse colon, bordered above by the stomach, and below by the small intestine, goes from one hypochondriac region to the other. It is generally found more distended than the other portions. The left lumbar colon descends from the hypochondriac region of the left side to the sigmoid flexure, being bordered behind and to its right margin by the left kidney, and in front by the small intestine. The sigmoid flexure, placed in the left iliac fossa, forms a convolution, but is very indifferently described by the term applied to it. It is occasionally very long and loose, and terminates at the left sacro-iliac symphysis. It is not unfrequently found destitute of the partitions which prevail in other parts. The Rectum begins at the left sacro-iliac symphysis, and passes INTESTINAL CANAL. 49 obliquely downwards to the centre of the sacrum, thence in front of the middle line of the sacrum, and of the coccyx, to terminate at the point of the latter. It is not regularly cylindrical, but, just above the anus, is dilated into a wide pouch, flattened from before back- wards by. the pressure of the bladder, and very distinguishable upon the introduction of the finger, for it is but seldom in a contracted state. It, of course, has a flexure by adapting itself to the concavity of the sacrum, and is bounded in front by the bladder, the prostate gland, and the vesiculae seminales of the male ; and by the vagina and the uterus of the female. The peritoneum covers only the superior two-thirds of the rec- tum, and attaches it by the short duplicature, called the mesorectum, to the front of the sacrum. A small pouch, passing down between the vesiculse seminales almost to the base of the prostate, is formed, as mentioned previously, by the peritoneum in its course from the rectum to the bladder. The muscular coat of the rectum has a thickness and redness sur- passing much that of any other intestine, and is divided very clearly into two laminae, the external of which consists in longitudinal and the internal in circular fibres. The external forms in itself a com- plete coat continuous with the longitudinal bands of the colon, but is much increased in thickness over them by additional fibres. The circular fibres also form a complete coat, and, just below the pouch of the rectum, are multiplied so much for eight or ten lines as to be a perfect internal sphincter muscle, bearing a strong analogy with the pyloric muscle of the stomach.* At the anus, an arrangement of the muscular coat prevails, which is not sufficiently attended to by anatomists. The longitudinal fibres, having got to the lower margin of the internal sphincter, turn under this margin between it and the external sphincter, and then ascend upwards for an inch or two in contact wflth the mucous coat, or rather its cellular substra- * It has been recently asserted that there is also a sphincter muscle four inches above the anus, half an inch wide in front, and one inch wide behind, from whence according to Mr. Velpeau the fibres go in crossing one another to fix themselves to the front of the sacrum. Mr. Lisfranc appears to have first announced it and Mr. Nelaton to have described it. Malgaigne, Anat. Chi- rurg. vol. 2d, p, 343. Paris, 1838. I doubt very much the uniformity of the distinct existence of such a muscle, not having been able to find it in the dis- sections which 1 have instituted for the purpose, unless a portion of the ordi- nary circular fibres should have been selected for that designation, in which case several others may be said also to exist. 50 ORGANS OF DIGESTION. turn, into which they are finally inserted by fasciculi which form the base of the columns of the rectum ; many of the fibres, however, terminate also between the fasciculi of the circular fibres. This connexion must have obviously much influence in the protrusions of the mucous coat, which take place in hemorrhoids and in pro- lapsus ani. The mucous coat of the rectum is thick, red, and fungous, and abounds in mucous lacunse and glands. It is smoothly laid above, but below it is thrown into superficial longitudinal folds called columns. At the lower ends of the wrinkles, between the columns, are small pouches of from two to four lines in depth, the orifices of which point upwards; they are occasionally the seat of disease, and produce, when enlarged, a painful itching. An original obser- vation of Dr. Physick, on the nature of this affection, and the remedy for which consists in slitting them open or removing them, induced me to look for the ordinary natural structure, which I have ascer- tained to be as now described.* The radiated wrinkling of the anus is from the influence of the external sphincter ani muscle. In some subjects, large cells are formed in the cavity of the rectum by transverse doublings of the mucous coat only, resembling the valvulse conniventes of the small intestine; this, however, is not the most frequent arrangement, though deserving of notice. It takes place under the following mechanism. About a finger’s length from the anus there is a puckering of the gut, or deep wrink- ling, such as occurs in the colon, and it arises from a similar cause, that is, an abbreviation of the longitudinal layer of fibres of the gut : this abbreviation is not wholly circular, but occupies the semi-cir- cumference of the gut on one side, and then a little higher up, the semi-circumference of the other side. This shortening of the gut brings the fasciculi of its circular muscular fibres more together, and, therefore, accumulates them into a greater thickness. At a corresponding part on each side of the gut in its interior, exists a transverse doubling of the mucous coat forming the valvula con- * See an interesting paper on Fistula in ano, by M. Ribes, in Mem. de la Societe D’Emulation, vol. 9, 1826; where the influence of this structure is alluded to. — Also, an elaborate and excellent article by Dr. Reynell Coates, in the Cyclopaedia of Pract. Med. and Surgery, Philada. 1835, under the term Anus. It appears that Glisson and Ruysch first described them as valves. The ac- curate Winslow (Douglas’ Translation vol. ii. p. 149, anno., 1749,) was also acquainted with this structure. INTESTINAL CANAL. 51 nivens alluded to. The result of this arrangement is a semi-circular valve on each side, one above the other, the margins, or diameters of which pass each other in the empty and contracted state of the rectum, but touching at the same time, and they present an addi- tional barrier to the involuntary evacuation of fseces.* Most subjects, however, have the mucous coat without these valves, and merely in superficial wrinkles of various directions. The large intestine is supplied with blood from a part of the superior mesenteric artery, from the whole of the inferior mesenteric, and from the internal pudic. Its veins empty into the vena portarum, its nerves are derived from the solar and the hypogastric plexus of the sympathetic. SECT. III. — ON THE MINUTE ANATOMY OF THE MUCOUS COAT OF THE ALIMENTARY CANAL, f In the preceding account of the mucous coat of the stomach and bowels, I have admitted the most generally received opinions as it is in every way proper for medical men to be aware of them. Having been, however, much occupied, a few years ago, in ascer- taining the pathology of Asiatic]; cholera by dissections, the obser- vations which I then made upon the healthy and diseased structure, have induced me to modify very much my former views, as will be seen in the following pages; the subject has since then been taken up largely by the anatomists of Europe, with nearly similar results. The mucous coat of the alimentary canal, in a healthy state, and successfully injected, appears to consist almost entirely of a cribriform intertexture of veins. These veins being commonly * It has latterly been advanced by Mr. O’Beirne, that in a natural state the rectum is empty, and that the accumulation of faeces preparatory to a stool occurs in the sigmoid flexure of the colon, where they are retained by a con- traction of the upper end of the rectum. The principal ground of this opinion is, that fcecal matter is rarely met with in the rectum. The observation is so contradictory to my experience in the dissecting room and on patients, that I cannot but reject it, though it appears to be obtaining some currency, or at least is quoted respectfully. Journal Hebd. 1833, vol. xiii. p. 126. Malgaigne, Anat. Chir. vol. 2d, 341. j" Anat. Atlas, Figs. 332 to 337, inclusive, the preparations by Dr. Horner represented by these figures are in the Anat. Museum. X Arner. Journ. Med. Sciences, Vol. xvi. May, 1835. 52 ORGANS OF DIGESTION. empty at death present themselves then as a soft spongy structure, which gives rise to the ordinary description of its sensible condi- tion as a velvety layer. The most minute injection of the arteries scarcely makes itself visible among these veins, when they are pro. perly injected also; a straggling branch only here and there exhi- biting itself. The arborescence of the arteries is confined to a level beneath the venous intertexture, and is there developed to an extreme degree of minuteness, being intermixed with correspond- ing venous ramuscles, generally larger and more numerous than the arteries themselves. This arrangement seems to occur in that surface of the cellular coat, which makes the base or ground of the mucous. The fine venous trunks of this deeper layer have their originating extremities directed vertically towards the cavity of the gut, and by that means receive the blood of the first venous intertexture or layer, as the petrous sinuses join the cavernous, or the veins of the penis arise from its spongy structure. The meshes of the first venous intertexture are exceedingly minute, and vary in a characteristic manner in the stomach,* small intestine, and large. This intertexture is very different in its looks from a com- mon vascular anastomosis, and produces in the colon an appear- ance resembling a plate of metal pierced with round holes closely bordering upon each other ; these holes constitute, in fact, the fol- licles of Lieberkuhn, so called from their discoverer ;f these folli- cles are gaping orifices, the edges of which are rounded off’, and their depth is that of the thickness of the venous anastomosis ; being bounded below by the arterio-venous layer , just alluded to, and by the cellular coat of the part. Nothing short of an entirely success- ful injection will exhibit this venous anastomosis as described ; and it may be seen either by injecting a vein, or an artery provided the injection passes from the arteries, into the veins, but the latter process is the least desirable, because we lose the benefit of a dis- tinction of colour between the two sets of vessels.^ * See fig. 332 to 335 inclusive. f De fabrica et actione Villor. intest. ten. Leyd., 1745. The observations more recently of Dr. Gaddi of Modena, have resulted in witnessing a similar indisposition of the arteries to ramify in the mucous coat, and the almost exclusive prevalence of the venous vessels there. He has some views beside of a peculiar nature, such as that the extremities of the veins begin by open mouths on the cavity of the intestine, then unite to form a hollow sphere situated in the submucous tissue, and that the terminating ends of the arteries discharge into these spheres or vesicles. Brit. & For. Med. Rev. Oct., 1841, p. 530. ANATOMY OF THE MUCOUS COAT. 5D Ordinary inodes of examination give no evidence of the existence m the alimentary canal, from the cardiac orifice of the stomach to near the anus, of an epidermis or epithelium; on the contrary, they rather lead to a belief of its being absent, in consequence of the softness, tenuity, and transparency of the mucous membrane ; but that it is really present, may be proved by the following process : — Tear off’ the peritoneal coat from a piece of small intestine — invert the part and inflate it to an emphysematous condition; the epithe- lium will then be raised as a very thin pellicle, and may be dried in that state ; but as this pellicle retains the air, we hence infer that it lines the follicles, and is uninterrupted by any perforations. This epithelium, if the part be previously injected perfectly, shows dots of injecting matter like those left in the rete mucosum upon a mi- nute injection of the skin ; but no arborescence of vessels if it be raised up from the veins, by the inflation stated. In so doing the villi disappear, are in fact unfolded. In addition to the above proof, the microscope in the hands of numerous modern observers now shows, according to the original opinion of Lieberkuhn, the existence of an epithelium over the whole alimentary canal, and which is fbrmed of minute soft scales. A Fig. 23. Cylinders of the intestinal epithelium, after Dr. Henle : — a. Cylinders from the cardiac region of the human stomach; b. the same from the jejunum, c. cylinders of the intestinal epithelium viewed by their free extremity; d. ditto, as seen in a transverse section of a villosity. The villi cannot be seen to full advantage except they be erected by an injection, in which case those of the upper part of the small intestine are found to run into each other very much like the con- volutions of the cerebrum, and to press upon each other’s sides in the same way. Some of them, however, are merely semi-oval Vol. II.— 6 54 ORGANS OF DIGESTION; plates, the transverse diameter of which exceeds the length or ele- vation. At the lower end of the small intestine they become sim- ply conical projections, somewhat curved, with the edges bent in or concave, and they retain this mechanism until they entirely dis- appear near the ileo-colic valve. In the whole length of intestine there is, however, every variety of shape of villi, from oblong curved and serpentine ridges, to the laterally flattened cone standing on its base ; the first condition changing gradually to the last in the de- scent of the bowel. Conformably to this definition of villi, none exist either in the stomach or colon, for there we have only the venous mesh. The villi of the jejunum are about the thirtieth of an inch high, and those of the ileum about one-sixtieth. In the ileum, the superficial venous layer has great regularity and the conical villi stand out beautifully from its anastomoses, or in equivalent language, from the divisions of the follicles. In the upper part of the small intestine the follicles are in equal number to what they are in the ileum ; the regularity of their arrangements being interrupted by the long serpentine and oval villi; but invaria- bly the same venous intertexture exists and forms, in both parts, the chief bulk of the villi, by passing into them. In the stomach the follicles vary much in size, and there is an arrangement whereby many of the smaller ones are seen to open into the larger: on an average about two hundred and twenty-five are found upon every square of one eighth of an inch, which would give of course to an inch square sixty-four times that amount, or fourteen thousand four hundred follicles. Conceding the w T hole stomach to present an area of ninety inches, which is probably below the mark when this organ is moderately distended, as exhibited in the prepa- ration upon which this calculation is founded, the entire number of follicles is one million two hundred and ninety-six thousand. The great uniformity of size of these follicles in the colon, and its even surface, enable us to count them with more certainty, and they appear to exist at the beginning of this gut at the rate of about four hundred for every eighth of an inch square, but in the sigmoid flexure at the rate of about two hundred to the same area ; they be- come, in fact, both smaller and less numerous in descending towards the anus. Their average may be stated, therefore, as three hundred for every one-eighth of an inch square — and as nineteen thousand two hundred for every inch square. Admitting the entire area of the colon to be five hundred inches, and nineteen thousand two ANATOMY OE THE MUCOUS COAT. 55 hundred of these follicles, to exist on every inch square, the aggre- gate number will be nine millions six hundred and twenty thousand. In the colon the resemblance is almost exact with what is called the perforated card or Bristol board, used by ladies for working em- broidery or variegated needle-work. Again, estimating the whole area of the mucous coat of the small intestine at fourteen hundred and forty inches, and allowing for in- terruptions occasioned by villi; about three hundred and ninety fol- licles exist upon every one-eighth of an inch square, or 24,960 upon an inch : say then, that about twenty-five thousand follicles are found upon every square inch, and the two numbers multiplied, produce thirty-six millions. The entire number of follicles in the whole alimentary canal, is, by the preceding estimates, forty-six millions nine hundred thousand , and upwards. I am very far from pretending to have counted them all, but have made an approximation to the actual number by ob- serving sections of different portions of the same subject, and verify- ing the observations upon other subjects. The external surface of the cutis vera presents, as it were, in outline, the same follicular arrangement; the venous reticular inter- texture appearing broader, not quite so perfect, and more shallow, and forming the papillae ; but as additional experiments are wanting, it may be passed over with this transient notice ; perhaps, in- deed, a more skilful hand in adopting the hint may perfect the details.* In the stomach, the largest of these follicles is about one-ninety eighth of an inch in diameter, and the smallest about one-four hun- dred and ninetieth. In the colon the largest is about one-two hun- dred and forty-fifth of an inch in diameter, and the smallest about one-four hundred and ninetieth. In the small intestines their size varies in about the same ratio as in the colon, but they are much more irregular in shape, being scattered more in groups, in conse- quence of the villi intervening: some of them penetrate obliquely towards the foundations of the villi ; hence, when examined from the exterior, their distribution is more regular, and they are seen lodged in the cellular coat of the gut. I have endeavoured to keep the estimate of the number of folli- * It is probably this which constitutes the bloody pimples (bourgeons sanguins) of the skin. 56 ORGANS OF DIGESTION. cles below what other calculators would make it upon an observa- tion of my preparations, and a fair measurement of the area of the alimentary canal, lest the number may seem excessive and incredi- ble ; I have, therefore, the most reasonable assurance of being within bounds on that point. I may now ask their use ; is it to secrete or absorb ? If they are simply secernents of mucus, the number, one would think, much greater than so limited a secretion requires — moreover, why is it that they become smaller and less numerous towards the lower end of the large intestine, where greater lubri- cation is required for hardened faeces ; in addition, are not the glands of Brunner, (solitaries,) and of Peyer, ( agminatce ,) amply sufficient ro furnish the required mucus? Again, after most sedulous obser- vations upon the villi of all kinds, finely erected by my injections, and placed under most accurate, simple, and compound micro- scopes, I find, invariably, a polished reflecting surface, uninterrupted by foramina, either at their ends or sides, while many of these fol- licles are found passing obliquely into their bases. An excellent Woollaston’s doublet, which makes the villi of the ileum appear an inch long, exhibits them with a polished translucent surface, without foramina, except where a villus from accident has been broken, a contingency readily recognised by one in the habit of viewing them. Finally, if the lacteal foramina of Lieberkuhn and others, do really exist, why is it that the raising of the intestinal epidermis by inflation, does not exhibit these foramina by the air escaping through them, but, on the contrary, admits of a dried preparation in that state, the villi being completely effaced.* Taking into consideration these several objections to the theory of the follicles being secreting orifices, it appears to me that a better idea of their use is called for, which suggestion is submitted to the profession, with the hope that a more capable person will remove the difficulty, by additional confirmation of preceding theories, or by the invention of a new one ; for my own part, I am much inclined to adopt the opinion of their absorbing faculties. It is generally con- ceded that the erection and prehension of the Fallopian tube is pro- duced by a vascular turgescence, in which the veins, from their num- ber, must execute an important part ; in like manner, as these intes- tinal follicles are formed in the midst of veins, their orifices only be- * In these and other microscopical observations, I owe much to my friend, Dr. Paul Beck Goddard, now Professor of Anatomy in the Franklin Medical College of Philadelphia. ANATOMY OF THE MUCOUS COAT. 57 come erect and patulous by the distention of those veins, and can- not be well seen by the eye alone, especially in the small intestine, unless an injection has succeeded fully; but the erection of these veins during digestion puts the follicles in a similar condition ; there is, therefore, some ground of inference, that the act of the Fallopian tube in conveying a germ, and of a follicle in conveying into the thickness of an intestine congenial matter, may be analogous. The follicles would seem at least not to be essential to the secre- tion of mucus, as it is found where the follicles do not exist; for ex- ample, in the frontal, maxillary and sphenoidal sinus, and also in the cavity of the tympanum. Notwithstanding the facility with which we can detect these folli- cles, I have failed entirely under various means of examination, in finding any orifices to Peyer’s glands, in the dried intestine : they appear to be merely small lenticular excavations* in its substance, and wherever a cluster of them exists, it disturbs the arrangement of the villi, and gives to them a scattered unequal distribution. 1 would also suggest very respectfully to anatomists whether our know- ledge in regard to them is sufficiently exact to render farther inquiry useless? for my own part it appears that this subject requires some additional attention. As they are found closed the probability is that their contents are discharged when required, by a regular dehis- cence. The above view, relative to the alimentary mucous membrane, presents at least a degree of novelty, by determining, with some pre- cision, the whole number of the Gastro-enteric Follicles of the human body, or Follicles of Lieberkuhn, and how they are in every instance formed by meshes of veins; while the arteries enter only inconsidera- bly into the composition of the same mucous membrane, to an amount in some measure comparable to the presence of the arteries in other erectile tissues, as the corpus spongiosum and cavernosum penis. In the latter it is familiar to every practised anatomist, that the branches of the arteries are but small, as they terminate in the cells of the penis, which are to be considered as only a modification of the incipient stage of venous trunks. If the corpus spongiosum were in fact spread out into a thin and single membrane, so as to line a * This observation has been confirmed in Germany by Boehm, who has, come to the same conclusion. He says that they contain a white milky and rather thick fluid, with numerous round corpuscles of various sizes, but mostly smaller than blood globules. Am. Journ. Med. Se. vol. xxi. p. 218. 6 * jS ORGANS OF DIGESTION. hollow viscus, it would present no very undue representation of what I have denominated the superficial venous layer of the alimentary canal ; it being also admitted that within the circuit of every anas- tomosis, a follicle was formed. Viewed on the preparations of the mucous membrane of the small and large intestines which I have, these follicles appear like puncta laohrymalia disseminated by thousands over every inch square, and existing so invariably upon every part, that, as I have stated, the smallest calculation of their numbers puts them at from forty to fifty millions. It may be stated incidentally, that it is the whole of this vascular and follicular structure, endowed with vital actions the most important to life, and presenting in the aggregate an area of about thirteen square feet, the size of a small breakfast table ; whose morbid derangements constitute the essential features of Asiatic cholera.* It has been shown in some of my dissections, that this apparatus in the pro- gress of cholera is detached entirely from the stomach and colon, in consequence of the excessive actions going on in them. The small intestines also, in some of my preparations, exhibit in patches a similar phenomenon ; but as the entire observation has been pre- sented to me in its true light only since the disappearance of the disease, I have had no means of ascertaining the extent to which they suffer in this way. The anatomy of the muciparous system of the alimentary canal unquestionably requires a more exact attention than is generally bestowed upon it, and especially so as to distinguish between that part which is really glandular, and the foramina or follicles now under consideration. The following extract will explain the diffi- culty which exists with some in regard to a proper conception of the latter. “The mucous glands, called also follicles or cryptse mucosae, are to the membranes of that name what the sebaceous follicles are to the skin ; that is to say, folds of the mucous membrane in form of a cul-de-sac , whose orifices open upon that membrane. These folli- cles have not yet been discovered over the whole surface of the mucous membrane; but here, as with the skin, analogy leads us to admit them. It is not long since they have been discovered in the pitui- tary membrane, where their existence had been denied. Be this as * For illustrative preparations by the author,, see Wistar Museum. ANATOMY OF THE MUCOUS COAT. 59 it may, we shall use the same observation upon these glands that was made on the sebaceous, viz., the impossibility of making an exact dissection of the capillary tissues does not allow us to discover all the forms of animal matter ; but wherever a particular humour is found in a tissue, we are forced to conclude that this latter is or- ganized in such a manner as to be able to produce it, and when in place of one humour we meet with many, we must acknowledge that the tissue is complex. Such is precisely the case with the mu- cous membrane of the digestive canal, and especially of the stomach, which could have a form of animal matter calculated to furnish di- gestive juices, although no gland destined to that purpose is dis- coverable.”* * * § In infancy, especially, the mucous glands have a sensible thick- ness, which enables us to see them, but the smallest of them require the aid of a microscope, and appear to have been described by Galeati.f As the paper is not to be had in any of the public libra- ries of this city, I can only quote from it on the current authority of anatomical works. In a note to the anatomy of the human body by Sir Charles Bell, article Intestine, it is stated as follows: — “It has been supposed that the fluids excreted from the surface of the intes- tines were furnished by very minute foramina, (which are visible by particular preparations,) in the interstices of the villi. See the letter of Malpighi to the Royal Society of London on the pores of the sto- mach, and the paper by M. Galeati in the Bologna Transactions, on the inner coat, which he calls the cribriform coat. The pores, ac- cording to Galeati, are visible through the whole tract of the canal and particularly in the great intestines.” Meckel designates these as glandular bodies under the name of glandules mucosa , crypta mi- nima. Another order of glands are those of Brunnei’4 They are readily found in the duodenum at all ages ; and particularly well in infancy, as low down as the ileo-colie valve. The third order are the glands of Peyer, discovered in 1677. § The celebrated Ruysch appears also to have understood the existence of the follicles of the stomach, and Swammerdam to have had some idea of those of the * Broussais’ Physiology. First American edition, p. 419. f Be cornea ventriculi et intestinorum tunica. Comm. Bonon., 1745. f Glandule intestini duodeni vel pancreas seeundarius; discovered in 1715. See Mangetus, Theat. Anat. § See also Mangetus for the description from Peyer. 60 ORGANS OF DIGESTION. small intestines,* * * § and he calls them tubuli glandulosi intestinorum in- teriors. I may here remark, that the figure of the villi of the small intestines given byHedwig, in his Disquisit. Ampullarum, &c. 1797, and which appears, from its introduction into Caldani’s and M. Jul. Cloquet’s Anatomy, to have a classical value, is, judging from my own preparations, too much a work of the imagination, executed under probably some fallacious views of the part itself: a cluster of cylindrical villi, with holes at the ends, would be an anomaly, for those of the upper part of the intestines are either serpentine folds, as represented in my preparations, with branches running into contigu- ous folds ; or semi-oval laminae ; while those lower down are of a flattened conical shape, somewhat bent, but in every instance they are destitute of what has been termed by Lieberkuhn an ampulla, and to my eye as stated have uniformly polished surfaces, uninter- rupted by foramina. Mascagni has also introduced views of a good kind in regard to the follicular structure of the stomach and colon. f But it is to Sir Everard Home, that we are indebted for one of the best papers on the glandular structure of the stomach of different anirnals.j; As the real muciparous glands have an orifice leading into each by the admission of anatomists, the follicles described commonly by them, are of this description, and are not comparable in number to the follicles found in the venous meshes. The highest estimate of the number of the former, as made by M. Lelut, fixes them at about forty-two thousand. § In consulting many of the distinguished modern authorities on this subject, there seems to be scarcely any thing in the anatomy of the intestinal canal which is presented in a more indefinite way; especially in regard to the small intestines, than the difference between the follicles, properly speaking, and the glands; and none of them, so far as I know, have previously to myself undertaken to approximate the entire number of the follicles and to point out how each one is the centre of a venous anasto- mosis, is formed by it, and always exhibits itself in a collapsed state when the vein is not turgid. || * Mangetus Theat. Anat. Vol. I. p. 310. f Prodromo della grande anatomia. Tab. xiii. X Phil. Trans. 1807 and 1817; and also his Comparative Anatomy. § Bouillaud, Traite du Cholera, p. 256. II The anatomy of the Gastro-intestinal mucous membrane has elicited HISTOLOGY OF MUCOUS MEMBRANES. 61 SECT. IV. — HISTOLOGY OF MUCOUS MEMBRANES. The extent of the mucous coat of the alimentary canal, and the important and varied sympathies which it has with most other parts of the body, render proper some remarks on membranes of this kind, generally. Mucous Membranes are so called from the nature of the secretion which they furnish: and the term having been first applied to the lining coat of the nose, a similitude of character has caused its extension to that of other organs. The celebrated Bichat, the founder of the science of general anatomy, was the first to adopt fully, and to perceive the value of this classification ; since which it has been almost universally received by anatomists. As the skin forms an external covering to the body, so mucous membrane lines the internal surface of the hollow viscera. When it is recollected that this membrane forms an internal tegument to the whole alimentary canal, from the mouth to the anus; to all the urinary and genital apparatus; to the whole respiratory system, from the nose down the trachea and throughout the lungs; it will be admitted that its extension exceeds much that of the skin. A mucous membrane presents two surfaces, one of which adheres to the contiguous parts, and the other is free by being internal. The adherent surface is attached by a cellular structure somewhat con- densed. This cellular structure is principally remarkable for its want of disposition to secrete fat into its interstices; a property of immense importance, as without it, obstructions would be con- tinually occurring to the destruction of life: it is pervaded by a multitude of fine vessels and nerves, running forward to be spent upon the mucous membrane ; and has been unfortunately named nervous coat , by anatomists of high authority. The strength of at- several good papers in Europe since 1835, inclusive, the period of my own publication, which was in anticipation of the others. In point of date they are rather confirmatory of preceding observations than distinguished by novel- ties, and the venous anastomosis does not seem to be understood or appreciated, except by Dr. Gaddi, of Modena, alluded to in a preceding note. In addition to the authorities already quoted, the reader may advantageously consult Boehm de Gland, Intest. Struct. Penit. Berol, 1835. Boyd on the Structure of the Mucous Membrane of the Stomach, Edinburgh, Med. and Surg. Journal, 1836. Likewise Recherches Anatorniques sur la Membrane Muqueuse, &c., par M. Natalis Guillot in L’Experience, p. 161. Paris, 1837-8, and Muller’s, Archives, 1838 and 1839. 6-2 HISTOLOGY OF MUCOUS MEMBRANE. tachment which it furnishes is somewhat varied ; for example, in the small intestinal canal I have often seen the mucous membrane caught at one end and entirely withdrawn from the muscular coat, an ex- periment which alone can give rigid ideas of its greater length, as by it all the duplicatures or valvule conniventes are stretched out. The experiment succeeds much more certainly by the regular pres- sure of a column of water between the tunics of the intestine. The mucous membrane of most organs is arranged into wrinkles and duplicatures, for the purpose of augmenting its extent. This ar- rangement prevails in the nose, and, as mentioned, in the oesopha- gus, in the stomach and intestines; to say nothing of many other instances which are noticed in the description of each organ. In some examples, they are permanent, and, in others, depend on the state of contraction of an exterior muscular coat. The interior face of the mucous membranes, allowance being made for the inequali- ties just stated, moreover, presents, when closely viewed, an abun- dance of more minute depressions and of elevations, causing it to resemble velvet. Some of these depressions are so large as to give it a cellular appearance,* as in many parts of the intestinal canal, and in the gall-bladder, and have been particularly described by Sir Everard Home. In regard to organization, the mucous membranes are of a soft, spongy consistence ; easily yield to mechanical violence ; and de- pend for their strength upon the .surrounding cellular coat. They are not of a uniform thickness ; for example, they are much thinner in the urinary and genital apparatus, than in the alimentary canal ; they also present some varieties of consistence. They yield very readily to putrefaction, and are quickly reduced to a pulpy state by the action of the mineral acids. Caustics of all kinds act more promptly on them than on the skin, owing to the protection of the latter by a dry epidermis ; Bichat states, that in the practice of the Hotel Dieu, this effect is frequently exemplified, by the administra- tion of lunar caustic among the common people for the purpose of poisoning. The nitric acid leaving the silver, quickly applies itself to the mucous membrane of the stomach, and disorganizing it, forms a whitish eschar, which, if life be preserved long enough, is finally detached in a membranous form. * They are not to be confounded with the follicles, but are a miniature re- presentation of what is called tripe, in culinary, language. HISTOLOGY OF MUCOUS MEMBRANES. 63 One of the remarkable properties of the mucous surfaces of the stomach and intestines is, that of coagulating milk. According to the experiments of Spallanzani, the gastric juice, in the living state, assists in this change ; but it is perfectly well known in domestic affairs, that the dried stomach of a calf, where the juices have been completely evaporated, is also productive of it. The observations of the same author led him to conclude, that the peritoneal and the muscular tunics of the stomach are insufficient to produce this effect. The internal surface of the mucous membranes is furnished with small projecting points or spiculse, called papillae or villi. They are particularly conspicuous and numerous, as mentioned, on the upper surface of the tongue and in the small intestine, and bear an analogy of function and organization with the very fine papillae which are seen invariably on the surface of the cutis vera. These papillae are constantly furnished with nervous filaments, giving them a high degree of sensibility ; and with an abundance of blood vessels. The term papillae has been more exclusively applied to the projections on the surface of the tongue, from their greater size ; they are there also more distinctly covered with an epidermis, frequently called epithelium, or periglottis. The villi, from their connexion with the process of digestion, have been emphatically denominated the roots of animals. According to M. Beclard,* who has examined them upon a plan of his own contrivance well suited to accurate microscopic observations, they are presented under a diversity of shapes. Those of the pyloric half of the sto- mach, and of the duodenum being broader than they are long, are composed of very small thin laminae, having a tufted arrangement. Those of the jejunum are long and narrow, having more the form commonly assigned to them, while in the lower part of the ileum and in the colon they again become laminated. It should be observed, that, notwithstanding the assertion of Leeuwenhoek, Hewson, Hunter, and others, tire fact is still called in question, by many of the most distinguished anatomists of the present time, MM. Beclard, J. F. Meckel, Rudolphi, Muller, &c., whether the orifices of the lacteals are, under any circumstances, visible on the surface of the villi. Admitting that they do not open * Anat. Gen. p. 253. These notions are not, however, in unison with my own, as just stated. Sect. III. 64 HISTOLOGY OF MUCOUS MEMBRANE. as stated, the power of interstitial absorption in the mucous mem- brane will still account for the chyle finally getting in the lacteals, as well as for fluids passing into the circulation from the stomach, when its continuity with the intestinal canal has been interrupted.* The Epidermis or Epithelium of mucous membranes is very dis- tinct at their external orifices, but becomes less and less apparent towards the interior of tire body, until it finally cannot be distin- guished by the eye alone ; and anatomists of a former period generally considered that it is entirely deficient, notwithstanding the assertion of Haller to the contrary. It is a matter of common observation, that when the interior of mucous membranes is exposed by an ever- sion for a long time, to the action of the atmosphere ; they take on more of the structure of skin, and become evidently covered with a cuticle which protects them and diminishes their secretion. This is exemplified in eversion of the vagina from prolapsed uterus, in elon- gated and tumid labia interna, and in other ways : restore the parts to their natural situation, and they are brought back to their original structure. In the partial prolapse of the mucous membrane of the rectum, from piles, corresponding circumstances occur. From this we infer, that the full development of cuticle depends very much upon the degree of exposure which any surface of the body has to undergo. The reverse also takes place : shut up or close any sur- face of the skin so that it is put in the condition of an interior cavity, and it immediately begins to assimilate itself to a mucous membrane. This is proved by the tendency in young children to a detachment of the cuticle, or excoriation of the opposed surfaces of the deep wrinkles about their thighs and in their perineum ; a tendency obvia- ted by the nursery practice of covering these surfaces with powdered starch. It is also manifested frequently in the dressing of wounds with sticking plaster, where an incautious approximation of the con- tiguous surfaces of the skin, not only is followed by excoriation, but even by ulceration. The existence of an epithelium every where on mucous membranes, now, is definitely settled by microscopical ob- servers, and has become one of the most established points of anatomy. This epithelium is formed by a continuous layer of cells not only in the gastro-intestinal mucous membrane, but in the va- rious prolongations of the latter into the ducts of the proximate glands * Should the suggestion of the absorbing powers of the gastro-enteric fol- licles which I have proposed in Section third, be correct, it will dispose of the difficulties and opposing opinions alluded to in this paragraph. HISTOLOGY OF MUCOUS MEMBRANES. 65 and in fact a similar arrangement exists wherever a mucous mem- brane is found. These cells are according to some the emanation of an amorphous basement membrane, they execute the specific secretion of the part which they cover, and thus whatever may be the similitude of their structure, perform very varied offices. Varieties of Cells or Corpuscles forming the epithelium of Mucous Surfaces. From Henle. Fig. 24. Fig. 25. Fig. 24 — a, 5, e, d, e, f. Nucleated ciliary cells; their free end straight and furnished with filaments, called Cilia, of different shapes, a, Nucleus. a , Cilia. Fig. 25. — A row of ciliated cells, rounded at end. a, In a line with nuclei. b. Cilia. Fig. 26. — Cylindrical cells apart with their nuclei. Fig. 27. — Cylindrical cells grouped compactly, a, Bodies. 6, Free extre- mities. The mucous membranes vary in colour from a very light pink to a deep red, which is owing to the blood that circulates in them. In cases of suffocation, they become almost brown from the congestion of blood in them, while in fainting they turn white from the desertion of the latter. The vessels after having penetrated the thickness of the membrane, ramify with extreme minuteness on its surface. The veins in an injection invariably predominate over the arteries by their greater size and distensibility. In consequence of their superficial situation, the vessels being unsupported on one side, are exposed to rupture from slight concussions ; in this way hemorrhage is produced in the lungs from coughing ; and bleeding at the nose from blows upon the head. Exhalant orifices exist in great numbers in the mucous membranes : this is especially the case in the lungs, where the pulmonary perspi- ration, as it is called, is very obvious to common observation. Else- Vol. II.— 7 ORGANS OF DIGESTION. (>() where, this discharge is so much blended with the mucus of the part, that it is difficult to appreciate its quantity. From the superficial situation of the blood vessels, it is clear that the exhalant orifices or pores, have but a short course to run. This is considered by Bichat as a satisfactory reason for the tendency of the blood to escape through them, or to ooze out where there is no rupture. Absorbents exist also in great numbers, as proved by the absorp- tion of chyle, of watery drinks from the intestinal canal, and by the inhalation of the vapour of spirits of turpentine into the lungs, rapidly communicating the particular smell of this article to the urine. There are, moreover, cases recorded of obstructed urethra, where the urine has been almost entirely absorbed by the mucous coat of the bladder. In regard to nerves, the mucous membranes are well furnished with them. Bichat has remarked that wherever these membranes are situated near the surface of the body and enjoy common sen- sibility, they are almost wholly furnished from the central portions of the nervous system, as the brain and spinal marrow : this is ex- emplified in the conjunctiva, the pituitary membrane, the palate, the glans penis, &c. On the contrary, the sympathetic nerve fur- nishes the intestines, the bladder, and the excretory tubes gene- rally. Mucous Glands, as they are called, exist throughout the system of mucous membranes, being situated either under them or in their thickness. From them is derived the mucilaginous fluid which lubricates so abundantly their interior surfaces, as to facilitate the passage of extraneous bodies, and, at the same time, to protect the membrane from mechanical violence. These glands are of various sizes, from that of the tonsils and the muciparous glands on the lips, cheeks, and root of the tongue, to the almost impercep- tible cryptse of the bladder and urethra. Their shape is either lenticular, rounded, or that of a pouch. The former two have l heir parietes of a sensible thickness, but the last are too thin to be distinguished from the mucous membrane itself. For the most part, the excretory duct of these glands is short and patulous, so as to lead directly into the substance of the gland. This is remarkably the case with the tonsils, which consist in a congeries of these fol- licles; and with the glands on the root of the tongue. In some animals they are so numerous as to form almost a distinct lamina to the intestines ; after the manner of the human subject, on the palate and parietes of the mouth. THE LIVER. 67 The Mucosity discharged from these glands is one of the prin- ciples of animals, and, as is well known, exists also to a great extent in some vegetables. When perfectly pure and fluid, it is white, transparent, inodorous, and insipid. It is insoluble in alco- hol, but soluble in acids. Water forms more than nine-tenths of it, the remainder is mucus, properly speaking, blended with some neutral salts of soda and potash. The mucus which covers the surface of the mucous membranes consists chiefly of separated particles of epithelium mixed with a fluid exudation, while the mucous follicles are said to pour out a fluid holding mucous globules suspended. The mucous membranes are exposed to a multitude of morbid alterations, such as polypus, scirrhus, cancer, phlegmorrhagia? or serous fluxes, blennorrhagise or mucous fluxes, inflammation in all its forms, gangrene, ulcerations, and congestions. CHAPTER V. Of the Assistant Chylopoietic Viscera. SECT. I. — OF THE LIVER.* The Liver ( Hepnr , Jecur) secretes the Bile, and is the largest glandular body in the human frame. It, as mentioned, occupies the whole of the right hypochondriac region, the upper half of the epigastric, and, as it becomes thinner in going towards the left side, it occupies a small space in the right superior part of the left hypo- chondriac region. Its whole superior face is in contact with the diaphragm; on the left it is bounded by the spleen, and below by the stomach, and the transverse colon ; behind it, are the vertebral column and the ascending cava. The shape of the liver is like one half of an ovoidal body cut into two in the direction of its long diameter, and having the thick- end turned to the right side. It is about ten inches in length bv six or seven wide, and w’eighs from four to five pounds in the * Anat. Atlas, Figs. 339 to 347, inclusive. 68 ORGANS OF DIGESTION. adult. Its colour is a reddish brown, generally; though, on its under surface and about its edges, broad blue or black patches are constantly met with, which do not indicate any morbid derange- ment. Its upper surface is of an uniform convexity, rather more promi- nent at the right posterior part than elsewhere ; adjusts itself accu- rately into the concavity made by the under surface of the dia- phragm; and is unequally divided from before backwards by the suspensory ligament. The anterior margin is thin, and is notched where the suspensory ligament begins ; the posterior margin is much thicker, and has near its middle a broad depression, to fit it to the projection of the vertebral column. The ascending vena cava forms a superficial sulcus upon this margin, and frequently there is a complete canal through the substance of the liver for transmitting it. The right extremity is very thick, and almost fills the hypochon- driac region of that side, while the left extremity is reduced to a thin, tapering, and flexible edge. The under surface of the liver is much more irregular than the upper; it is traversed in an antero-posterior direction, in a line cor- responding with the attachment above of the suspensory ligament, by the umbilical fissure, ( Sulcus Umbilicalis ) which extends from the notch in the front edge to the depression behind, and obtains its name from having accommodated in the foetal state, the umbilical vein, now converted into a round ligamentous cord. In the poste- rior part of this fissure is likewise to be seen, in the same condition, what remains of the ductus venosus. The anterior portion of the umbilical fissure is notunfrequently converted into a complete canal, by a portion of hepatic substance crossing it like a small bridge. The transverse fissure ( Sulcus Transversus , Intermedins) is situated in the middle of the under surface of the liver, and extends along a third or fourth of the long diameter of the latter. It begins some- what to the left of the umbilical fissure, and crossing it at right angles, proceeds towards the right extremity. It contains the vena portarum, the hepatic artery, and the hepatic duct, lymphatics and nerves ; all of which are bound to each other by a close cellular substance. The suspensory ligament above, and the umbilical fissure below, give occasion to divide the liver into Lobes, Right and Left ; of which the right is by much the largest, and accommodates almost entirely the transverse fissure, having also on its under surface some THE LIVER. 69 subordinate elevations, to wit, the Lobulus Spigelii and the Lobulus Quartus, together with the Gall-Bladder. The Lobulus Spigelii is placed between the transverse fissure and the posterior margin of the liver, to the right of the posterior end of the umbilical fissure. Its shape is somewhat prismatic, bifurcating in front ; one of the elongations or prongs is a papilla overhanging the transverse fissure, and is, therefore, considered as one side of the gate-way {porta) opened for the vena portarum ; the other elongation is a small ridge, sometimes called Lobulus Caudatus, and is lost gradually on the under surface of the great lobe, by inclining to the right. The Lobulus Quartus, or Anonymus, is not by any means so elevated as the last, but having a flattened surface, is placed in front of the transverse fissure, between the fore end of the umbilical fis- sure and the gall-bladder ; its posterior extremity is the other side of the gate-way {porta) of the Liver, and is just opposite to that fur- nished by the Lobulus Spigelii. The liver, from being completely enveloped in peritoneum, has a smooth glossy appearance. The reflections of this membrane, from it to die parietes of the abdomen, form the ligaments, as they are called, which consist each of two laminae.. The Falciform Liga- ment, or Suspensory, containing in its anterior margin the remains of the umbilical vein, now called Ligamentum Teres, begins at the umbilicus, extends from it along the linca alba and the middle line of the diaphragm, and, as mentioned, is reflected to the upper sur- face of the liver, from the anterior to the posterior margin. The Right Lateral Ligament is situated behind, and departs from the back part of the diaphragm to the posterior margin of the right lobe. The Left Lateral Ligament also goes from the back part of the diaphragm, and is attached along the posterior margin of the left lobe. Where the suspensory ligament inclines on each side into the lateral, it passes with so much obliquity as to leave some portion of the poste- rior margin of the liver uncovered by peritoneum ; the latter, where it describes the periphery of this space, has been rather unnecessarily designated as the- Coronary Ligament. In addition to the peritoneal coat, the liver has. another, connect- ing it with the peritoneum, and seeming to be only condensed cellular substance, which also penetrates into the substance of the gland, and holds its constituent parts together. It is particularly well seen within the circle- of the coronary ligament. 70 ORGANS OF DIGESTION. Of the Organization of the Liver. The glandular substance of the Liver is fragile and easily lace- rated ; and consists of a congeries of spheroidal or polyhedrical grains, called by Malpighi acini from their resemblance to small berries ; they are best seen on tearing the organ, are united in mass by the elongations of the cellular coat, and traversed by the trunks of the blood vessels. Each of these granulations is about the size of a millet seed, and is a representative of the entire gland, as its structure is complete in itself ; being formed by the capillary termi- nations of the blood vessels, and by the origins of a branch of the hepatic duet, called the porus biliarus. The liver is made extremely vascular by the ramifications of three kinds of blood vessels, the Vena Portarum, the Hepatic Artery, and the Hepatic Veins. The first two convey the blood to it, and the third removes it again, into the general circulation, by emptying into the ascending vena cava. There are also the commencing radicles of the Hepatic duct; the Lymphatic vessels; and the Nerves. When examined with a microscope, the acini are seen to be made of smaller graniform bodies, and also present under particular cir- cumstances two colours, a brown and a yellow. This difference of colours, observed originally by Ferrein,* gave occasion to the division of the substance of each acinus into Cortical (Substantia corticalis, brunnea,) and into Medullary, (Substantia medullaris, flava) the pro- priety of which is, however, not fully sanctioned even at the present day. The Cortical or brown matter is the investment of the other, and depends for its colour, principally upon the great proportion of capillary vessels, derived from the three orders, the vena port®, arteria hepatica, and vense hepaticm. The Medullary or yellow matter, is the place of origin of the biliary ducts, and is supposed to derive its colour from the presence of bile in their radicles. f The ground of this distinction is so unsatisfactory and it seems to depend so much upon some contingent condition of the circulation of the blood, that while it is admitted by very eminent authority, as Bichat and J. F. Meckel, it is as earnestly rejected by equally high, as * Mem. de Paris 1735, Hist. 51. f The application of those terms has been changed, as Ferrein called the brown matter the Medullary, and the yellow, the Cortical. THE LIVER. 71 Portal and E. H. Weber. My own observations have been such as to incline me to the authority of the two latter. Some new microscopic details have been attached to the account of the Liver within a few years, by Purkinje and Henle, and are fully confirmed by Wagner and others. The proper hepatic structure, the parenchyma of the liver, it would thus seem is composed in the case of each acinus, of a collec- tion of epithelial cells, so near together as to have their shape moulded by mutual contact, and to become polyhedrical. They are about the 1-7000 of a line in diameter, and have a nucleus of about the fourth or fifth of that size. Hallman has placed these structures at a much smaller size, about one-tenth of the diameters stated : and Wagner makes them much larger, amounting in fact to 1-100 of a line. There are other measurements of an intermediate kind, showing all together that there are great diversities in their real magnitude.* These cells have their shape varied from a flattened spheroidal to a quadrangular or pentangular one, and con- tain within them a yellow bilious looking material, having intermixed with it several globules of fat large and small. The biliary matter contained in them is concluded to be proof sufficient of these cells being the real agents of the secretion of bile. The essential features of this process then consists in the successive evolution of these cells, of their active elaboration of the bile — of their rupture or dehiscence and of the further conveyence of the bile into the pori biliarii, by a process as yet not fully understood. The existence of these hepatic cells is easily ascertained: by tearing a liver especially a young one, and then scraping it, they turn out so abundantly that allowance made for the blood vessels, and cellular or areolar tissue, they seem to compose it almost wholly. The idea of Huschke in regard to their connexion with the pori biliarii is, that the bile is elaborated in their central nucleus, as proved by nitric acid, and that an extremely attenuated branch of a bile duct 1-684 of a line in diameter, reaches each cell, being attached to it like a pedicle, and in that way receives the discharge of bile. He believes that the fat of the hepatic cell or vesicle, seen also upon its surface, is converted into bile. This view of the terminal points of the biliary ducts is very much a repetition of the penicillous structure of former anatomists, its arrangement being perhaps more attenuated than any they had an idea of. He says that to the present moment * Huschke Traite de Splanchnologie, p. 123. 72 ORGANS OF DIGESTION. lie has never witnessed the reticulated connexion of the fine extremi- ties of the bile ducts in their origin from the acini, which are repre- sented in the ideal figure of Mr. Kiernan. Also that he has not found the anastomoses of the larger bile ducts, said to have been discovered by the latter, in the left hepatic ligament; and he has been equally unsuccessful in detecting the communications said by Berres to be, between the blood-vessels and the biliary ducts. My own injections of the liver, considered by good judges as very successful and not inferior in that respect to some upon which a new anatomy of the liver has been founded, exhibit a very high vascularity upon the periphery and in the intervals of the acini; this vascularity falls off’ much in the substance itself of the acinus; and is then repeated in the centre of the acinus in originating the corres- ponding branch of the hepatic vein. These preparations are now of many years standing. A similar exposition has been made by Du- jardin and Verger,* who assert that the parenchyma of the lobules, (acini) is absolutely without vessels and interior plexus, being- made of oval gelatinous corpuscles, in the intervals of which the blood corpuscles move. The commencing radicles or ramifications of the Hepatic Duct , take their origin in the acini. The larger branches converge into their respective trunks successively or in pairs ; while the primordial, or most minute ones, converge several of them to the same point, giving a penicillous appearance. These several tubes constitute the Biliary Pores (Pori Biliari) and are always in the same group with the branches of the Vena Portarum and Hepatic Artery. It is un- settled whether these brush-like or penicillous ends of the pori biliarii are enlarged at their free extremities so as to be there like a pin at its head, in a manner so common in glandular structure. Krause asserts the fact, and states that the enlargement measures from to of an English line, and there are said to be preparations of the kind in Utrecht. f It is asserted that a fine injection passes more readily from them into the lymphatics than into any other order of vessels; which may account for the promptitude of jaundice upon an obstruction of the hepatic duct. The most minute branches * Husohke ut supr. p. 124. f Muller, Phys., p. 491. London, 1840. THE LIVER. 73 of the biliary ducts in the acini are so close together that they seem to be united to one another, Their diameter, according to Midler, varies from to is of an English inch ; they are, therefore, much larger than the finest capillary blood vessels. A case of obstruction of the hepatic duct by a medullary mass, in the practice of Professor Geddings of South Carolina, in arresting the bile produced a distention of the extreme biliary canaliculi, which were observed by him to commence in cceca closely impacted one against another.* The Venaj Portarum having arisen from the junction of all the veins of the stomach, intestines, pancreas and spleen, is about three inches in length when it reaches the transverse fissure, of the liver by going over the duodenum and under the pancreas. It immediately divides into two branches, called collectively the Sinus Venae Por- tarum, which is at right angles with the trunk of the vein. The right branch being the shortest and largest, is distributed by radiating trunks to the right lobe of the liver ; the left branch is distributed, after the same manner, to the left lobe, to the lobulus Spigelii, and to the lobulus quartus. Some of its branches anastomose with the hepatic veins, which accounts for the ease with which an injection will pass from one to the other. The vena portarum is finally reduced into extremely attenuated ca- pillary extremities, whose diameter is from to tW of a line in diameter according to Weber. They invest the acini, penetrate them to some extent, and anastomose freely together in observing this arrangement. Their meshes are occupied according to Weber almost wholly by the biliary canaliculi, but just doubts are now en- tertained whether they do more than come in contact with them, contrary to an opinion formerly held that they discharge into or anas- tomose with them. Their final termination is in the corresponding branches of the Hepatic veins, the freedom of which communication there is no difficulty in proving by injection as well as by the ordinary laws of the circulation of the blood. The Hepatic Artery is a branch of the coeliac, and in approaching the transverse fissure divides into three or more branches, that pene- trate the substance of the liver, between the sinus venae portarum and the ducts as they come out ; one branch goes to the right lobe, * North Am. Journ. 1835. | Anat. Atlas, Fig. 350. 74 ORGANS OF DIGESTION. another to the left, and a third to the lobulus Spigelii. There is some variety in regard to the precise mode of distribution ; and their division into subordinate ramifications frequently occurs, before they get fairly into the substance of the liver. When there, they seem to be intended for the nourishment of this organ, and follow the ramifications of the vena portarum and of the biliary ducts, forming upon them a very delicate and complicated tissue of anastomosing vessels ; some of which, probably the vasa vasorum, communicate with the vena portarum. The hepatic artery having been reduced into extremely fine branches is found expending itself upon the walls of the vena por- tarum and of the biliary ducts ; it must of course, supply itself with nourishing blood, and also the parenchyma of the liver; and it finally makes a plexus in the case of each acinus intimately blended with the ultimate plexus of the vena-portarum, with which it has a free communication as readily proved by injection. There ought to be but little doubt that the vena portarum is the primary recipient of its blood. The analogy is established in the gall bladder, where the cystic artery discharges into the cystic vein : the latter then proceeding to the vena portarum, is sufficient proof of the compatibility of this ar- rangement. The venous vasa vasorum of the vena portarum is also in favour of it. But whether such termination is exclusively in the vena portarum may give rise to a question. Many of the finer branches of this artery ( Rami serosi) reach from the interior to the surface of the liver, and running out a great length with almost uniform size make, under the peritoneal coat, a most beautiful and exquisite reticulation by their own branches, and those of adjoining vessels of the same kind. A reticulation so fine that it strongly resembles a lymphatic one. The Hepatic Veins arise in the acini from the capillary termina- tion of the vena portarum and the hepatic artery. Their branches are successively accumulated into three large trunks, the collective area of which vastly exceeds that of the vessels bringing the blood to the liver. Two of these trunks come from the right lobe and one from the left, to empty into the ascending cava, while it is still in contact with the liver, immediately below the diaphragm ; just below the preceding trunks there are five or six, sometimes more, small hepatic veins, coming from the posterior margin of the liver, and from the lobulus Spigelii. The hepatic veins are destitute of valves, and remarkable for the thinness of their parietes. An injection passes THE LIVER. 75 readily from them into the other systems of vessels. They may be recognised by their insulated course, and by their consisting in trunks which converge from the periphery of the liver to the vena cava, while all the other vessels diverge from the transverse fissure to the peri- phery, and consequently cross the course of the hepatic veins. The larger branches of the venae hepaticse exhibits a remarkable number of very small branches with patulous mouths a sixth of a line or less in their diameter, which come directly from the contiguous acini; having arisen by still smaller extremities in connexion with the capillary terminations of the other blood vessels of the liver. The number of such foramina gives to the sides of the hepatic veins a cribriform appearance. The branches of the hepatic veins seem to free themselves more completely from their entanglement with the other vessels near the centre of the acinus, and then pursue a course to themselves not difficult to follow out. Owing to the involution of one set of the hepatic capillaries with another, there is an essential and almost insurmountable difficulty in forming a conception, or making a preparation which will elucidate their ultimate arrangement. In explanation of this difficulty Mul- ler considers that there is an ulterior plexus of capillary blood vessels with which the other three communicate freely, this is pro- bably the fact, including the lymphatic system also; but the precise mode of its formation is as yet not ascertained, an idea long ago ad- vanced by Chaussier in regard to all glandular structures. According to the valuable observations of Mr. Kiernan,* the acini of Malpighi should be called lobules, inasmuch as they consist in the collection of smaller granulated bodies, to which he restricts the name of acini. The objection to this principally is that it intro- duces a new definition, on a point heretofore considered as settled in the universal phraseology of anatomists. His statement then is that the finer branches of the vena portarum, which he calls Interlobular veins, make a perfect and minute plexus surrounding the lobules or small granular masses of the liver ; they then form convergent lines of vessels directed towards the centre of each lobule and communicating by transverse branches with one another. These latter connexions or the sets of veins making them, constitute the lobular venous plexus, and in their intervals are placed what he calls the acini or subordinate granules. He says, also, that the Hepatic Duct forms a plexus upon the * Anat. and Physiol, of Liver, Phil. Trans. London, 1833. 76 ORGANS OF DIGESTION. lobules like that of the vena portarum ; the plexuses of the contigu- ous lobules being indisposed to anastomose, though he thinks there is ground to believe in such anastomosis. The interlobular biliary ducts then penetrate the lobule and ramify by anastomotic connex- ions through it.* The Hepatic Artery, he says, makes also a plexus upon the surface of the lobule, and penetrates interiorly from its periphery towards the centre, to end in the vena portarum. Meckel says, that they end in the incipient branches of the venae hepaticae. The Hepatic veins, according to Mr. Kiernan, are seen as a small trunk in the centre of a lobule; this trunk arises from the conver- gence of from four to eight venules, from the periphery to the cen- tre of the lobule. It is stated by Mr. Kiernan, that the elements of the above ar- rangement of ducts and blood vessels are formed very distinctly in the left lateral ligament of the liver. He appears not to have succeeded in injecting the hepatic veins from the hepatic artery, though he can inject them from the vena portarum. His injection was probably not fine enough, as there is not the slightest difficulty in filling all the ducts and blood ves- sels of the liver from either set, provided one throws in a very fluid injection ; the use of water simply will prove this beyond doubt. Mr. Kiernan’s statements appear to have been received as decisive by his countrymen, both anatomists and physiologists, and by some of the continental anatomists; generally, without much apparent ex- amination for themselves. In some respects he has, judging from his figures, been peculiarly fortunate by finding in his dissections the lines of blood vessels upon the same plane and so clear; when their general course, according to common experience, is so tortuous, un- even, and implicated. A greater reserve has been manifested by the German teachers, thus there is a remarkable discordance between his observations on the incipient state of the biliary pores, and Krause’s and Huschke’s, the latter speaks pointedly of the ideal figure of Kiernan. Wagner, * According also, to Weber and Kroninberg, the incipient extremities of the biliary ducts make a net-work in the acini. Weber says, that the diame- ter of these branches, is from the 1-1340 to the 1-900 of -an inch. That the blood capillaries have a diameter of from the 1-1959 to the 1-1463 of an inch, and that the distance passed by the blood from the smallest portal, to the smallest hepatic vein is from the 1-80 to the 1-70 of an inch. Muller’s Arch. 4184 . THE LIVER. 77 of accomplished skill as an anatomist, in admitting that angular cells form the lobules, {acini) and that these are separated, one from the other, by cellular substance, asserts cc that he finds it much more difficult to say how the different vessels — the last divisions of the vena portae, of the venae hepaticae, and of the ductus hepaticus com- port themselves in the interior of the lobules. I regard the beautiful figures and the descriptions of Mr. Kiernan, as the best and most accurate that have been published, although they very certainly also include many mistakes.”* At the bottom of tlje transverse fissure of the liver is to be found a dense cellular fibrous tissue, which invests the vena portarum, the hepatic artery, and the biliary ducts ; and, as they all keep together in their ramifications, this tissue follows them throughout the substance of the liver, and thereby forms sheaths for them. It may be considered as continuous with the processes sent in from the cel- lular coat ; and, contrary to the opinion of Glisson, whose capsule it has been called, it is devoid of muscular structure. The lymphatics of the Liver are large, numerous, and deprived of valves, hence they can be readily injected and make a brilliant close plexus on its surface, from which mercury soon subsides owing to the freedom of their communication with the deeper lymphatics. They leave it by various routes in large trunks which ascend and depart by the several ligaments. The nerves of the liver are branches of the solar plexus of the sympathetic, and reach it through the transverse fissure in com- pany with the blood vesels. The liver appears in the embryo to be originally formed by a protrusion of the walls of a part of the intestinal canal ;f the lungs and pancreas present a similar mode of evolution. Fig. 28. Secreting cells of the Human Liver; z, nucleus; b, nucleolus ; c, oil-particles. Of the Gall-Bladder The Gall-Bladder ( Cystis Fellea) is a reservoir for the bile, secreted by the liver. It is fixed on the under surface of the great lobe, to * Elements of Physiol; London, 1842. f Muller, loc. cit, p. 490. j: Anat. Atlas. Figs. 348, 349. Vol. II.— 8 78 ORGANS OF DIGESTION. the right of the umbilical fissure, and removed from the latter by the lobulus quartus.* It is an oblong pyriform sac, having its anterior extremity or fundus projecting somewhat beyond the an- terior margin of the liver, while the posterior end reaches to the transverse fissure. Its long diameter inclines slightly to the right side, so that it is not precisely in an antero-posterior line. It varies in its shape in different subjects, being much more spheroidal in some than in others. Its fundus is rounded and obtuse, while the posterior end is gradually reduced to a narrow neck, which is bent upon itself, so as to retard the flow of a (lui^ through it. Its upper surface is in contact with the substance of the liver, and is received into a broad shallow fossa, while the lower surface is projecting, and by coming in contact with the transverse colon, tinges it with bile, by transudation after death. The Gall-Bladder has three coats, a peritoneal, a cellular, and a mucous one. The Peritoneal Coat is not complete, but only covers that part of the sac not received into the fossa on the under surface of the liver; it is, therefore, a continuation of the peritoneal coat of the latter; sometimes, however, the gall-bladder is so loosely attached to the liver that it almost hangs off from it, in which case the peritoneal coat is nearly complete. The Second coat is condensed cellular membrane, ( Tunica Pro- pria.) Through it ramifies a great number of lymphatics, and blood vessels; below, it attaches the peritoneal to the mucous coat, and above, the latter to the liver. The Mucous Coat is always tinged of a deep green or yellow, by the bile which it contains percolating after death ; for it is said to be, before that, of a light colour. This coat is thrown into irregular tortuous folds or wrinkles of extreme delicacy, in the intervals of which are many round or polyhedrous cells, causing it to look, when floated in water, like a fine honeycomb: such as are about the fundus of the sac are superficial, and not so distinct; but those near its middle and about the neck, are a line or a line and a half deep. In the neck or apex, and in the beginning of the cystic duct, are from three to seven, sometimes twelve semilunar duplicatures of the internal membrane, which also retard the flux and afflux of any * I have seen an instance where it was to the left of the umbilical fissure, on the small lobe. The latter was much longer than common. Dec. 1830. THE LIVER. 79 fluid, though they do not afford so much resistance to the ingress as to the egress of it. These duplicatures are sometimes partially ar- ranged into a spiral valve, projecting from the inside of the duct, and forming two or three turns.* Very small mucous follicles exist over the internal face of this membrane, the discharge of which fills the gall-bladder when the secretion of bile has been interrupted by dis- eased action, as in yellow fever, or by scirrhus of the liver. The artery of the gall-bladder is a branch of the hepatic. Its veins empty into the vena portarum. Its nerves come from the sympathetic, and its lymphatics join those of the liver. The gall-bladder is developed as a diverticulum, from the Hepatic Duct. Of the Bile Buds. A succession of very fine branches having arisen from the acini of the liver, these branches are united into three or four trunks by the time they reach the transverse fissure. The trunks then coalesce into a single Duct, the Hepatic, of eighteen or twenty lines in length, and about the diameter of a writing-quill. The Hepatic Duct is then joined at a very acute angle with the Cystic duct or that from the gall-bladder, which is somewhat shorter and smaller; the union of the two forms the Common Duct, ( Dudus Communis Choledochus.) The latter is larger than either of the others singly, and is three or three and a half inches long ; it descends behind the right extremity of the pancreas through its substance, passes nearly an inch, obliquely, between the coats of the duodenum, becoming at the same time diminished in diameter; and, finally, ends by an orifice still more contracted, on the internal face of this gut, at its second turn, and about three or four inches from the stomach. The orifice is marked by a small surrounding tubercle somewhat obscured by the valvuke conniventes. The Hepatic, the Cystic, and the Common Duct are situated, as mentioned, along the right margin of the lesser omentum, and have the vena portarum and the hepatic artery to their left. The bile ducts are formed by two coats ; the external is a fibrous, * Discovered by M. Amussat, of Paris. He has also detected muscular fibres in the gall-bladder and biliary ducts, in which we see an analogy with other hollow viscera. — Am. Jour. Med. Sciences, Vol. ii. p. 193. SO ORGANS OF DIGESTION. lamellated, and very extensible membrane, while the internal is mucous, having the same structure with that of the gall-bladder, of which it is in direct continuation. In the Cystic Duct, and at the lower part of the Common Duct are several longitudinal folds. The Common Duct sometimes receives, just before it empties into the duodenum, the Pancreatic Duct. Of the Bile. This secretion from the liver, is of a deep yellow, sometimes green colour : when recent, it is thin and fluid ; but after it has been conveyed to the gall-bladder, and permitted to remain there for some time, it becomes as thick as molasses, and increases also in the intensity of its colour and in bitterness. Some anatomists have believed that there was a more direct communication between the liver and the gall-bladder than that through the hepatic and the cystic duct ; but repeated and close observations have proved the opinion to be erroneous, or at least destitute of proper proof : it is therefore, clear, that the difference between the hepatic and the cystic bile, depends upon the watery particles being removed from the latter by the absorbing power of the internal coat of the gall- bladder. According to Berzelius, the chemical analysis of bile furnishes about eighty parts of water, eight of a particular substance, Biline, which assumes a resinous condition on the application of an acid: three of mucus ; and nine of saline matters ; of which soda is a principal constituent. SECT. II. — OP THE SPLEEN.* The Spleen, [Lien, Splen ,) is situated deeply in the posterior part of the left hypochondriac region, and is bounded above by the dia- phragm, below by the colon, and on the right by the great end of the stomach, and by the pancreas. It is not ascertained that it secretes any thing. Its colour varies from a deep blue to a dark brown. In shape it resembles the longitudinal section of an oval, being flat or very * Anat. Atlas, Figs. 351 to 354, inclusive.. THE LIVEH. 81 slightly concave on the surface next to the stomach, and convex on that contiguous to the diaphragm. Occasionally its margins are notched, but this is not invariably the case. Its flat surface is slightly depressed longitudinally in the centre ; into a fissure which is imperfect, and where the blood vessels enter into it, by six or eight foramina. Several spleens sometimes exist in the same individual, in w T hich case the supernumerary ones are not larger than nutmegs. The common size of this organ is about four and a-half inches long, by two and a-half or three wide, in wdiich case it has a solid firm feel ; but it very often exceeds these dimensions ; its transition and va- rieties of magnitude are so frequent, that no settled rule can be established. In its inordinate enlargements I have seen it only a little smaller than the liver ; its texture in this case is soft and easily lacerated. It is fixed in its place by three lines of reflection or processes of peritoneum, called ligaments, whose names indicate their places of attachment. They are the Gastro-Splenic Ligament or Omen- tum, which passes from the stomach to the spleen, and in which are the vasa brevia of the stomach : the Splenico-Phrenic Liga- ment, which goes from the spleen to the diaphragm, attaching itself to the latter at the left of the oesophageal foramen, and then descending along the posterior internal face of the spleen, in a line, behind the gastro-splenic ligament: and the Splenico-Colic Ligament, which passes from the spleen to the colon, being, as it were, a process from the left extremity of the gastro-colic omentum. These reflections, by being continued over the spleen, give it a complete peritoneal coat, which is raised up with more difficulty than the corresponding membrane of any other viscus of the abdomen, and is cominonlv thrown into very small inequalities or wrinkles. The internal or proper coat of the spleen is a grayish, compact, extensible, and elastic membrane, the use of which is evidently to sustain the natural shape of the organ, and to support its parenchy- matous structure. It sends in processes to accompany the blood vessels (capsulae Malpighii) and from its internal face there proceeds a multitude of lamellae and of fibres, which traverse its cavity in every direction, and reduce it into a cellular condition, not unlike the cavernous structure of the penis. Of the Intimate Structure of the Spleen . — The spleen, in propor-. tion to its size, is furnished to a remarkable degree with blood. The 8 * 82 ORGANS OF DIGESTION, largest branch of the eoeliac artery runs to it along the superior mar- gin of the pancreas, forming numerous serpentine flexures, and dis- tinguished for its thickness and size ; it divides into several trunks before penetrating into the spleen, and enters by the foramina in the fissure. The veins come out by a number of trunks equal to what the artery is divided into ; they assemble then into a single trunk, which attends the artery along the pancreas, is destitute of valves, and empties into the vena portarum. The Splenic artery having penetrated into this organ, is divided and subdivided into a radiating succession of very fine branches, which, according to the injections of Ruysc.h, do not anastomose with each other ; in consequence of which one part is sometimes finely injected and not another. This corresponds with my own ob- servations. The veins, on the contrary, do anastomose, not only as regards the collateral branches of the same primitive trunk, but also by the collateral branches of different trunks. These anastomoses are not large. The veins of the spleen are remarkable for the tenuity of their coats, and for the great disproportion of their area, with that of the arteries, which in the larger trunks is rated at five to one, and in the smaller at twenty to one. The larger veins look cribriform when viewed from their interior, owing to the number of fine branches which they receive. The veins of the spleen, in their ramifications through this organ, besides their frequent anastomoses, undergo sinus-like enlargements, approaching the structure of the corpus cavernosum penis, and their walls are formed merely from the internal venous coat. The ar- teries terminate freely in the veins, as may be proved by fine injec- tions, and by the microscope. The mass of the spleen upon superficial examination, seems to consist in a dark brown bloody pulp, (Substantia rubra) which is contained in the cells dividing the cavity of the internal coat, and may be easily demonstrated by tearing or cutting the spleen, and scraping it with a knife handle. The pulpy substance of the spleen under the microscope, is com- posed of small spheroid or oval granules of a reddish brown colour, and about the size of the globules of the blood. According to Mr. Gulliver,* they are more unequal in size than the blood discs, their diameter, varying from 1-6000 to 1-1777 of an inch, and they are * Gerber’s Gent. Anat. p. 102.. TOT SPLEEN 83 found in blood taken from the splenic vein. They are easily sepa- rated from one another. The minute arteries of the spleen ramify in tufts among their gra- nules, and then terminate in a plexus of venous canals whose walls are so thin that the veins appear as mere channels in the pulp. A question has arisen whether the pulp (substantia rubra) be extrava- sated in the cells which contain it, or whether it be still retained in the extremities of the blood vessels. Superficial examination is in favour of the first, but M. Marjolin denies it on the following grounds; that injections, cautiously made, pass immediately from the arteries into the veins ; and that the spleen, w r hen successfully injected and frozen does not exhibit ice in the interstices of its vessels, while their capil- lary ramifications distended by the injected fluid, are distinctly seen. From these facts he concludes that the glandular structure of the spleen is formed essentially of arterial and venous capillary vessels with very delicate and extensible coats ; that they communicate with one another without the intermedium of any cell ; and that the extreme tenuity of these vessels, and their extensibility in every di- rection, are sufficient to explain the augmentation of volume of the spleen, under certain circumstances, as well as the promptitude of its diminution under others. MM. Assolant and Meckel believe that blood besides being in the arteries and veins, is placed in a state of particular combination and of intimate union with the other organic elements of this viscus, and with a large quantity of albumen ; and that this combination of the blood forms the dark brown pulp alluded to. The great quan- tity of albumen in the pulp, is readily proved by the hard coagulum which it forms, when steeped in alcohol. In addition to this pulp, many observers have met in the spleen with an abundance of rounded corpuscles, (Corpuscula Malpighii,) varying in size from an almost imperceptible magnitude to a line or more in diameter.* They are of a gelatinous consistence, soft, grayish, and semi-transparent, and either cluster together, or are widely separated and have a diameter of from one-sixth to a third of a line. Their exact structure is undetermined. By Malpighi, they were considered glandular, and by Ruysch,f as convoluted vessels. Professor Soemmering from the following paragraph, seems to join * Malpighi, Ruysch, Hewson, Home, Dupuytren, Meckel, &c. f Epis. Anat. IV. 84 ORGANS OF DIGESTION. in the opinion of the latter : “ Qui nonnunquam occurrunt, acini vel glomeruli, microscopii ope accuratissime explorati, nihil sunt nisi vasorum fasciculi, vel teretes penicilli aut cirri vasculosi.” Accord- ing to the observations of Sir Everard Home, they swell consider- ably after an animal has finished drinking. The corpuscles are seen with difficulty in the human spleen, in animals they are much more distinct, as in the hog, sheep, and ox. Muller* admits their connexion with the arteries, but is inclined to consider them as excrescences from their coats, as in his injections the arteries were seen to pass through, but not to ramify in them. Their real existence has been much contested, owing to the un- certainty of finding them, but it now seems to be admitted, that the best spleens for this purpose are such as are perfectly healthy, and taken from subjects who have died suddenly. A little delay dis- poses them to become putrescent, and more pulpy, as it does the red substance of this organ. Those of a brownish red are best suited for the investigation. The corpuscles of Malpighi are at least vesicles, with very thin parietes, hence when punctured, their fluid which is found of an al- buminous character, escapes, and they collapse. They are some- times in a group of six, suspended to an arterial ramuscule like a pedicle. The vessels do not penetrate them but are confined to their exterior, where they form a very fine net-work. The fluid which they contain, is according to Bischoff and Huschke, white, with a multitude of globules swimming in it, and looking very much like chyle. Huschke after much inquiry into their structure, considers it most probable that they are dilatations of the lymphatic vessels of the spleen, from their analogy with the interior of a splenic or me- senteric lymphatie gland of an infant; and he thinks all that remains to verify the conjecture is an obvious connexion with some lymphatic vessels, afferent and efferent. By Simon they are considered as aggregations of Cytoblasts.f The spleen has many lymphatic vessels; and is furnished with nerves from the solar plexus. The spleen, from having no excretory duct, and consequently, from our inability to ascertain whether it secretes, has its uses unknown. No single theory concerning it has ever been generally adopted, for speculations have multiplied in proportion to the obscurity of the Physiol, p. 618. f Brit, and For. Med. Rev. p. 567. April, 1816. THE SPLEEN. 85 subject. By some it is thought to exercise merely a mechanical function— by others, a chemical one' — by others, a dynamic — and in the midst of such uncertainty, some have concluded that it had no special function. The hypothesis which to me is most reasonable, is, that of its acting a subsidiary part to the liver. It would seem, indeed, as a general rule in regard to glandular struc- tures and such other highly vascular organs of the body as have an intermittent function, that the blood which is sent to them during their state of activity, should be passed off through a different channel, while they are in a state of repose. This does a double service, it prevents superfluous secretion, and it also keeps up the vascular equilibrium of the body; as there must be always in readi- ness a quantity of blood sufficient for the supply of any secretion which may be wanted for the time. This proposition will derive some additional illustrations from the foetal state. The kidneys being then inactive the capsulse renales take off their blood, and thereby prevent w’hat would otherwise be a very inconvenient secretion of urine; again, the lungs being also then inactive, the circulation through them is proportionately re- duced, and the superabundant blood is conducted through the thy- mus gland. But as the full functions of the lungs and of the kidneys are established upon birth, and continue uninterrupted during life ; their supplementary organs respectively, as the thymus gland, and the capsulae renales, not being wanted ; wither away after the early- period of infantile existence is passed. In regard to the liver, its functions also suspended during the fcetal state, are of an intermittent kind throughout life, the spleen may, therefore, be considered a vicarious organ for it, during the whole period of existence; receiving its blood during the continua- tion of uterine life, and in the intermission of action, during common life. The spleen is, therefore, an organ useful to the fcetal and to the perfect state, and we, consequently, never see it in the collapsed and effete condition of the thymus gland, and renal capsules. The same reasoning which applies to the spleen, will also apply to the Thyroid Gland : the latter may be considered as executing for the salivary glands during foetal and perfect existence, what the spleen does for the liver. F or the salivary glands being inactive during foetal existence, have only an intermittent action during per- fect life; and, therefore, probably stand in need of a supplementary organ during their periods of inactivity. 86 ORGANS OF DIGESTION. SECT. III. — OF THE PANCREAS.* The Pancreas ( Pancreas ) secretes saliva, and is the largest of the salivary glands. It is fixed in the lower back part of the epigastric region ; and extends horizontally across the spine, being separated from it by the lesser muscle of the diaphragm. It is connected to the spleen on the left ; at its right extremity is surrounded by the curvature of the duodenum; is bounded in front by the stomach, which conceals it; and is placed between the two laminse of the mesocolon. The pancreas is about six or seven inches long, two wide, and flattened before and behind. Its figure would be represented by a parallellogram, were it not that its right extremity is enlarged con- siderably into a head or tuber, to which Winslow gave the name of the Lesser Pancreas. The anterior face of this organ is turned ob- liquely upwards, and is covered by the superior lamina of the meso" colon. The posterior face looks obliquely downwards, and is in contact with the aorta, the vena cava ascendens, the superior mesen- teric vessels, and several nerves : along the superior margin of this face exists a long superficial fossa, occupied by the splenic artery and vein. With the exception of the loose covering given by the meso- colon, the pancreas has no peritoneal coat; neither has it an ap- propriate tunic, unless we consider as such the lamina of con- densed cellular membrane which envelops it, and sends in processes, between its lobules, as in the case of the salivary glands in the neck. Of the Minute Structure of the Pancreas . — This body, like the other glands, w'hich discharge saliva, is of a light gray or pink colour. It consists in lobules of various forms and sizes, united by an intermediate cellular tissue, and having their interstices occu- pied by numerous blood vessels. These lobules, by a slight mace- ration, may be separated and resolved into small granular masses, constituting integral portions of the gland. The arteries of the pancreas come principally from the splenic, as it cruises along the superior margin. The veins empty into the * Anat. Atlas, Fig. 354. THE SPLEEN. 87 splenic, and thus, finally, into the vena portarum. It is furnished with nerves from the solar plexus, and has lymphatics. The excretory duct of this gland ( Ductus Wirsungii ) arises, by very fine roots or tubes, from each of the small granular masses. These roots have vesicular commencements like those of the sali- vary glands. The tubes coalesce into larger ones, which run trans- versely from the periphery towards the centre of the gland, inclining slightly, at the same time, towards the right. These secondary tubes finally discharge successively into a single one, which runs the whole length of the gland nearly in its middle. The single tube, by these additions, enlarges continually from left to right, being small where it begins at the splenic extremity of the pancreas, and about the size of a crow-quill at the duodenal. At the latter place, it is joined by the duct of the lesser pancreas, which is derived after the same rule as itself. The pancreatic duct, almost immediately afterwards, emp- ties into the ductus communis choledochus ; or runs at the side of the latter, and makes a distinct opening near it into the duodenum, at the posterior part of the second curvature. The diameter of the cell-like extremities of the duct of the Pan- creas is from six to twelve times greater than that of the capillary blood vessels. BOOK V. OF THE URINARY ORGANS. The Urinary Organs, ( Organa Oropoietica) being destined to secrete and convey the urine out of the body, consist in the Renal Capsules, the Kidneys, the Ureters, the Bladder and the Urethra. Of the Renal Capsules. The Renal Capsules ( Capsules Renales , Renes Succenturiati ,) are two small bodies, one on either side, placed upon the upper end of the kidney. They are of a yellowish brown colour tinged with red, have no excretory ducts, and are more distinctly developed and softer in the perfect foetus than in the adult ; whence they are ranked among those organs, as the thymus gland, and others ; which, having some peculiar value in foetal existence, are perhaps unnecessary to that of the adult. * They are of a triangular pyramidal shape, flat- tened before and behind, and rest by a concave base upon the kid- neys ; they are about fifteen lines high and as many wide. They are surrounded by a proper coat of lamellated dense cel- lular tissue, which, by detaching inwards its prolongations, keeps the parts of these bodies together, and marks out their divisions. In the centre of the renal capsule, a cavity may, from time to time, be found ; but, according to my own observations, nothing in our structure is less certain than its existence ; and, in the opinion of Meckel, when found, it is the result of cadaverous decomposition. In the foetus it contains a reddish viscid fluid, which seems to con- sist in a large share of albumen, as it coagulates with alcohol; in * This opinion has been confirmed in a dissection of a fetus, where I found the capsulae renales, though the kidneys were absent. Vol. II.— 9 90 USINARY ORGANS. \ children, this fluid becomes yellow: in adults it is dark brown ; and in old people it is either entirely deficient, or in a remarkably small quantity. Of the Minute Structure of the Capsules Renales . — The arteries of these bodies come from the emulgents, from the phrenics, and from the aorta. The veins of the right one terminate in the cava ascendens, and of the left in the left emulgent. Each one is divisible into lobes, and by a slight maceration may be reduced into lobules and small granulations. The granulations seem to have an intimate connexion with the veins, as they are easily penetrated by fluid in- jections from the latter. The external part is rather more consistent and yellow than the internal ; hence, a division has been adopted into cortical and medullary portions. In the cortical portion, the minute arteries and veins are about the size of the capillaries of other parts, and are of nearly uniform magnitude. They are arranged in a radiated manner, so as to run in lines from the surface towards the centre. The arteries anasto- mose with the adjoining branches, so as to form very long meshes: the veins do the same. On the periphery of the organ there is an ordinary capillary net-work of vessels. A spongy venous tissue composes the greater part of the medullary or more interior portion ; this spongy tissue receives the radiated venous branches of the ex- terior, and discharges its own blood into a large vein (Vena supra- renalis) in the interior of the organ. Muller,* in addition to the above, says that the only cavity in this organ is the vein just alluded to, and that by forcing air into the vein the whole medullary tissue may be distended. Examination with the microscope, by Mr. Gulliver, f exhibited the proper structure or pulp as formed of spherules, from the m-ho to the Wtni of an inch. Alleged excretory ducts for these bodies have been found going to the testicle, to the pelvis of the kidney, and to the thoracic duct, but no credit is now attached to such assertions. * Physiol., p. 621. j Gerber’s General Anatomy, Appendix, p. 103. London, 1842. THE KIDNEYS. 91 Of the Kidneys.* The Kidneys ( Renes ) are two glandular bodies for the secretion of urine, fixed one on either side of the spine. They are in the back part of the lumbar regions, have their internal edges inclining very slightly forwards, and extend from the upper margin of the eleventh dorsal to the lower margin of the second lumbar vertebra : the right, however, is ten or twelve lines lower than the left, owing to the thick posterior margin of the right lobe of the liver, which presses it downwards. The kidneys are covered in front by the peritoneum and the lumbar portions of the large intestine, but in such a manner as to be separated from them, in corpulent subjects, by a surrounding layer of fat ; behind, they repose upon the lower part of the great muscle of the diaphragm, upon the quadrati lum- borum, and upon the upper end of the psose magni muscles. The kidney is a hard solid body, of a brown colour ; in shape it is a compressed ovoid, excavated on the margin which it presents to the spine, and bears a very strong resemblance to the common kidney bean. Its flat surfaces present forwards and backwards, and the broad end of the ovoid is above. Its periphery is smooth, so that one does not infer from an external examination, the lobules or internal divisions. The excavation of the kidney, next to the spine and called its fissure, ( hilum renale ) occupies about one-third of its long diameter, is bevelled in front, and leads to the very interior of the gland; conducting its blood vessels and excretory duct, which have to pass through a quantity of cellular and adipose matter. The kidneys are generally of equal size, being about four inches long, and two wide ; and each one weighs three or four ounces. They have no ligaments for keeping them in position, but depend for the latter upon the adjacent cellular adhesions and blood vessels. The kidney being destitute of a peritoneal coat, has a well marked capsule which envelopes it entirely and penetrates into its fissure for some depth, where it is perforated with foramina for transmitting the blood vessels and the ureter. This capsule is white, semi-trans- parent, fibrous, strong, and elastic : it adheres to the surface of the kidney by delicate cellular and vascular filaments, which are so weak that they permit it to be stripped off without difficulty, and * Anat. Atlas, Figs. 356 to 368, inclusive. 92 URINARY ORGANS. when so removed, some indications of a lobulated condition of the organ are seen. Of the Minute Structure of the Kidney. — The lobulated state of the kidney is well marked in the foetus ; and some of the lower orders of animals, as the bullock, exhibit it very clearly through life. In the human adult subject, by tearing the kidney up according to the superficial lines marking a tendency to the lobulated condition, it will be found that there are really about fifteen divisions of it, more or less, each of which constitutes a small kidney (Renculus.) When the kidney is cut open longitudinally, it obviously consists of tw r o kinds of substance, differing in their situations, colour, consistence, and texture. The one making the periphery of the gland is called from its position Cortical, ( Substantia Corticalis, Gla?idulosa,) while the other, being more internal, is designated as the Medullary or Tubular, (Substantia Medullaris ; Tubulosa ; Fibrosa.) The Cortical or Secretory Substance forms the whole circumfer- ence of the kidney, and, on an average, is about two lines in thick- ness ; but it is thicker at some points, as, from its internal face, pro- cesses converge towards the centre of the gland, which separate the tubular part into as many distinct portions of a conoidal shape. It is composed largely of arteries and veins ramifying, among small granular corpuscles (Corpora Malpighiana, or Glomeruli.) It tears with facility, thereby presenting this granular appearance, and is of a dark or reddish brown colour, varying considerably, however, ac- cording to the cause of death. The Granular corpuscles which form the mass of the cortical or secretory substance, are, individually, merely visible to the naked eye; but are very distinct when viewed with a microscope. They present themselves as innumerable small round points more red than the other portions of the surface inspected. Their diameter approaches the tenth of a line, some being less. They are attached to very fine arterial twigs, like a berry to its stem, and are so dis- engaged in their position in the cortical part of the kidney that they may be lifted out of their beds with the point of a needle, especially in the horse. The celebrated Ruysch, who was distinguished for the success ot his injections, and for the acuteness of his vision, declared that they consisted wholly in clusters of very fine extremities of arteries THE KIDNEYS. 93 and veins having a penicillous arrangement; while Malpighi and Schumlansky viewed them as purses or small sacs of a glandular cha- racter, specifically suited to secrete urine, and upon whose parietes the blood vessels ramified. From these granuli or acini the incipient extremities of the tubuli uriniferi, they asserted, take their rise. The Tubular or Conoidal Substance, consists in from twelve to eighteen conoidal fasciculi, say on an average fifteen [Pyr amides Malpighiance ) presenting their rounded bases towards the cortical matter, and enclosed in it, while their apices converge to the central cavity of the kidney, the surface of which they form. The bodies of these pyramids, as just mentioned, are separated by processes of the cortical matter; but their apices are free, and project from the internal surface of the kidney so as to resemble as many small nip- ples, whence they are called Papillae or Mammellae Renales. Fre- quently two of the pyramids coalesce so as to form but one papilla together ; in such case the latter generally preserves a duplicate ap- pearance. The papillae are arranged into three vertical rows, one before, one in the middle, and another behind ; those of the foremost row are turned backwards ; those of the middle look inwards ; and those behind look forwards. Not unfrequently, there is a small de- pression (foveola) on the very summit of the papilla. The tubular part is of a lighter colour and harder than the cortical, but the dif- ference in these respeets is not always manifest and sometimes is reversed. The conoidal fasciculi may each be considered, along with its appertaining cortex, as a sort of distinct gland ( Renculus ,) or at least as a lobe ; for upon them depends the lobulated appearance as stated of the kidney of a foetus, and of animals. Each cone, when analy-. zed, is found to consist in a collection of tubes (Ductus Uriniferi Bellini ) converging from the ciicumference of the kidney to the apex of the papilla. These tubes are more numerous near the base of the cone, in consequence of their successive junction subsequently in approaching the apex :* their terminating orifices, on the latter, ap-. pear like small pores from which the urine can be squeezed in little drops. In the early part of the course of the ductus uriniferi, while they * Schumlansky, Diss. de Struct. Renum, Strasburg, 1782. 9 * 94 URINARY ORGANS. are still in the cortical matter, they are wound about in a very ser- pentine and tortuous manner, and are distinguished by the name of Cortical Canals, ( Ductus Ferrenii .* * * § ) They there commonly go alone, winding their way in the cortical substance until they reach its most interior face ; they then become straight, form the tubular substance, and have the name of the conduits or uriniferous ducts of Bellini. f Some of the calculations on this subject are not a little curious. It was ascertained by Ferrein that in each of the conoidal fasciculi (Pyr amides Malpigl nance) there were, at least seven hundred subor- dinate cones or pyramids, ( Pyr amides Ferrenii ) and as the number of conoidal fasciculi is generally about fifteen, these pyramids would amount to ten thousand five hundred. Again, each of the subordi- nate pyramids is composed of many hundred uriniferous tubes, and, by the observations of Eysenhardt,j; each of these tubes consists of twenty smaller ones. The cortical canals or ducts of Ferrein, it is believed by many, terminate at their peripheral extremity, by forming loops upon them- selves, and anastomoses with contiguous similar canals. § It is also held by some, as Wagner, that in addition to this mode of termina- tion others of those canals end in caeca or blind extremities, which are either single or bifid. Should the observations in this respect turn out correct, the arrangement has been at least found more de- cided and frequent in the lower animals than in man. Iduschke|] and John MullerU have denied the connexion of the Granular corpuscles with the Ducts of Ferrein. The former says that if the ureter be injected by the pneumatic machine, the injection will be found never to reach the Malpighian corpuscles, though an injec- tion of the arteries at the same time will, and the two injections will remain apart. He hence infers that these bodies are merely the twisted tufted ends of the blood vessels, being an arrangement preparatory to the real secretion of urine from a subsequent capillary network, made of arteries and of veins. This network surrounds the cortical canals, and is displayed upon them, without, however, anastomosing with them. In opposition to this view, besides the * A. Ferrein; sur la Structure des reins et du foie. Mem. de l’Ac. des Sc. Paris, 1749. j- L. Bellini, de Structura Renum Florence, 1662. f: De Struct. Renum Obs. Micros. Berlin, 1818. § Muller, Krause, Owen, Weber, See Muller’s Physiol. 2nd ed. p. 496. || Traite de Splanch. p. 298. De Gland Struct. Leips. 1830. THE KIDNEYS. 95 testimony of preceding anatomists, we have a very good paper, by W. Bowman, of King’s College, London,* * * § showing by injections this connexion of the corpuscles and the ducts of Ferrein; and that the arteries and veins make there a tufted junction with one another. He asserts that each one of these corpuscles is actually included in the extremity of an uriniferous tube, which enlarges to receive it, that the arterial filament that supplies it after forming its tuft emerges as an efferent trunk, and is then merged in the capil- lary plexus investing the uriniferous tubes. This view has been measurably confirmed by Gorlach.f It appears that in the Boa Constrictor, there is a vena portarum to the kidney — some approach to which Bowman considers to exist in the human subject, under an arrangement stated by him. The Kidney receives from the aorta one or more branches, called the renal or emul- gent arteries, which divide as they approach the fissure ; and having got into the substance of the gland are distributed by innumerable twigs to all parts of it. The veins equal in number the arteries, and are somewhat larger. When both, or even one, of these systems of blood vessels is injected with wax and cor- roded, its branches are so abundant as to re- tain the form of the gland. In engaging in the fissure of the kidney, the arterial ramifi- cations are in front, the veins in the middle, and the commencement of the ureter be- hind^ The artery on the right side is longer than that on the left. The reverse is the case with the emulgent veins, as they empty into the vena cava ascendens. This arrangement is owing to the relative position of the aorta and the vena cava ascendens, as the first is on the left side of the spine, and the last on the right side. The arteries of the kidney, in ramifying * Transactions Royal Society, London, part 1st, 1842. f Am. Journ. Med. Sciences, p. 442. April, 1846. X According- to Bowman magnified about thirty diameters. § This rule is subject to frequent variations. Fig. 29. f Arrangement of the Re- nal vessels; in the Kidney of the Horse: — a, branch of Renal artery ; af, affe- rent vessel ; m, m, Mal- pighian corpuscles; ef, ef . , efferent vessels; p, vascu- lar plexus surrounding the uriniferous tubes; st , tube of Bellini, ct, tube of Ferrein. 96 URINARY ORGANS. minutely through its structure, adopt the following arrangement. They first of all pass through the processes sent inwards from the cortical matter between the Pyramids of Malpighi, or large cones and, having got fairly into the cortical matter, they divide into very fine twigs, which form arcades around the bases of the pyramids of Ferrein, and pass between them.* These arcades have anastomoses with each other, and their larger branches go almost exclusively to the cortical substance, but few of them being found on the tubular. The branches radiate from the convexities of the arches, so as to surround the base of each cone, and to penetrate to the surface of the kidney. Some of these branches terminate in corresponding veins, and others on the granular corpuscles or acini. The connexion between the corpuscles and the arteries, has been compared to that between grapes and the stems on which they grow, so as to form a bunch. The veins penetrate the substance of the kidney, and have a similar distribution ; but they are much larger than the arteries, and have free, large and numerous anastomoses. A con- nexion of the corpuscles with the veins is not quite so evident, and, even if it does exist, remains yet to be adequately proved ; at least, in the opinion of many anatomists. The fact, however, is well esta- blished, that fine injections will readily pass from the veins into the tubuli uriniferi; and that air blown into the ureter will pass readily into the veins. In my own injections these have been done repeatedly, and the corpuscles of Malpighi are seen very distinctly to be formed of convoluted arteries; I have not seen the veins convoluted under the same arrangement, neither have I succeeded in tracing the corti- cal canals to these corpuscles or acini. From the concave side of the arterial arcades very fine capillary branches converge in company with the ducts of Bellini in a line with them, and penetrate to- the free surface of the papillae renales. Upon this surface is made a highly attenuated capillary intertexture, the meshes of which surround the orifices of the tubuli uriniferi. The converging arteries anastomose across the tubuli, making elongated meshes. A similar arrangement of the veins takes place from their cortical branches and arcades, it being in company with the arterial arrangement. The facility of injecting these minute tubular arteries and veins has frequently given rise to the mistake of considering them as the tubuli uriniferi themselves ; an error which has been pointedly marked out by Miiller.f * Schumlansky. f Physiol, p. 225. THE KIDNEYS. 97 The nerves of the kidneys come from the solar plexus of the sym- pathetic ; and adhering to the arteries cannot be traced very far through the glandular structure. The quantity of lymphatics is con- siderable. The kidneys are subject to a false position ; in one instance, I found in a young female subject, one of the kidneys in the pelvis in front of the rectum. A similar case has been seen by Professor Hen- singer,* and since then, others have been recorded. I have met with several instances of a coalition of the two kidneys, across the spine, so as to present the appearance of a bilobed organ. Of the Excretory Dud of the Kidney , or the Ureter, f The Ureter is a canal which conveys the urine from the kidney to the bladder. It commences in the centre of the kidney by an en- largement called pelvis , which branches off into three or four por- tions, ( calices } ) one above, one below, and one or two intermediate. Each of these calices, is divided at its free extremity, into three or four short funnel-shaped terminations, ( Infundibula .) Each of these terminations embraces by its expanded orifice, the base of a papilla renalis, so as to permit the latter to project into it, and thereby to distil its urine there. Very frequently the number of papillae exceeds that of the infundibula, in which case two of the former project into one of the latter. The pelvis of the kidney having emerged at the fissure behind the vessels, from being expanded and conoidal in shape is reduced to a cylindrical canal, which, properly speaking, is the ureter : the latter is about the size of a goose-quill, and descends through the lumbar region, between the peritoneum, and the psoas magnus muscle. It dips into the pelvis by crossing in front of the primitive iliac vessels and the internal iliac, crosses the vas deferens at the back of the bladder, and penetrating obliquely the coats of the latter, terminates in an orifice ten or twelve lines behind that of the neck of the bladder. I he excretory duct of the kidney is formed by two coats. The external is a dense, fibrous, and cellular tissue, but is destitute of any thing like muscle. The internal is a thin mucous lamina, which * Amer. Med. Jour., Yol. iii. p. 442. f Anat. Atlas, Fig. 359. 9S URINARY ORGANS. can be raised up without much difficulty, and is continuous, at its lower end, with the internal coat of the bladder ; at the upper end, it is supposed by some anatomists to be reflected over the papillm, and even to pass for some distance into the tubuli uriniferi. This duct has considerable powers of extension, as manifested by its transmitting large calculi from the kidney, and also, by its enormous enlargement in some cases of obstructed urethra ;* its sensibility is exquisite when irritated by a calculus passing down it. The walls of the tubuli uriniferi are the surface upon which the secretion of urine most probably takes place exclusively. The mu- cous membrane of the pelvis of the kidney being continued over them so as to form the surface; these canals, delicate as they are, exhibit an epithelium formed of nucleated cells. These cells, discovered by Henle, are close together without being angular ; according to the phy- siological views of the case in all glands, they are the real elaborators of the urine, and upon becoming distended with it, they burst, and let out their contents into the tubuli uriniferi; being then decomposed a new generation of cells is produced from the nuclei of the extinct ones. They have to pass through the same series of changes, and, thus it proceeds to the end of life. Corpora Wolffiana .f The Corpora Wolffiana, called after their discoverer, are small bodies found only in the earlier stages of foetal life, one on each side in the lumbar region, and of which there are scarcely any traces at the end of the fifth month. When in full development, they are so large as to conceal the kidneys and the renal capsules, but as these latter organs grow, the corpora Wolffiana diminish, and are finally placed lower down. They are supposed to be vicarious kidneys for the time, and they consist in transverse coscal tubes, which are nu- merous. They have each an excretory duct, which leads from their lower part into the Sinus Uro-genitalis. The latter is also peculiar to the foetal state, and is a tube which for the time receives from each side the ureter, the vas deferens, and the duct of the corpus Wolffianum ; and is prolonged into the urachus. The Sinus Uro-genitalis is finally divided into two branches, from * See Wistar Museum, f Anat. Atlas, Fig. 369. THE BLADDER. 99 one of which is evolved the urinary bladder, and from the other the vesiculse seminales.* * * § Of the Bladder. \ The Bladder ( Vesica Urinaria ,) is the reservoir for the urine, and is placed in the pelvis, just behind the symphysis of the pubes. When pressed upon, as it commonly is, by the adjacent viscera, it is flattened somewhat before and behind ; but removed from the body and inflated, it is an elongated sphere or an oval: the greatest diameter of which is vertical, in regard to the linea ileo-pectinea. The superior end of the bladder is called the upper fundus, and the lower end the inferior fundus ; the latter is rather more obtuse than the other; and between the two is the body. The neck of the blad- der is its place of junction with the urethra. The form of the bladder is influenced by age and by sex; in very young infants it is cylin- droid, and owing to the smallness of the pelvis, rises up almost wholly into the abdomen. In the adult woman, who has frequently borne children, it is nearly spherical, has its greatest diameter transverse, J and is more capacious than in man. The bladder is bounded in front by the pubes, above by the small intestine, behind by the rectum, and below by the prostate gland and the vesiculse seminales. From its superior end there proceeds to the umbilicus a long conical ligament, the urachus, which is placed be- tween the linea alba and the peritoneum, and produces a slight ele- vation or doubling of the latter. In mankind, the urachus is solid ; but some very rare cases are reported, in which it has been hollow, so as to permit the urine to flow through it from the bladder. This anomalous conformation has generally been attended with a con- genital obstruction of the urethra. § When the anterior parietes of the abdomen are put upon the stretch, a semi-lunar fold of the peri- toneum, as formerly mentioned, is seen to proceed, on either side of the urachus, from the lateral surface of the bladder almost to the um- bilicus. These folds contain, in their free edge, the fibrous remains of the umbilical arteries of the foetus, called subsequently to uterine life, the Round Ligaments of the bladder, though they have little or * Muller’s Phys., p. 1639. f Anat. Atlas, Figs. 370 to 375, inclusive. X H. Cloquet, Anat. Descrip. § Sabatier, Anat., vol. iii. p. 19. 100 URINARY ORGANS. no influence on its position. The bladder is also fixed in its situation by the pelvic aponeurosis, a membrane elsewhere described with the organs of generation. The bladder consists of four coats : the Peritoneal, the Muscular, the Cellular, and the Mucous. The Peritoneal Coat is very imperfect, and is derived from the part of the peritoneum which descends from the anterior parietes of the abdomen into the pelvis. It covers the upper and the posterior face of the bladder, and then passes to the rectum, by sinking down between these two organs, so as to form the small pouch beneath the lower fundus of the bladder ; the apex of this pouch reaches within an inch of the base of the prostate. The upper margin of this pouch next to the bladder, forms a strong horizontal doubling, stretching across the pelvis, when the rectum is empty, and is on a level with the posterior end of the vesiculse seminales. Being connected to the subjacent muscular coat by a thin lamina of loose cellular membrane, the peritoneum may be dissected off without difficulty. In consi- derable distentions of the bladder, it is reflected from the upper end of the latter to the abdominal muscles in a line much above the pubes ; whereby a good opportunity is afforded of reaching, with an instrument, the cavity of the bladder without injuring the perito- neum. The Muscular Coat is of a thickness intermediate to that of the stomach and of the oesophagus, and its fibres are pale. They pass in very varied directions,* and are collected into flattened fasciculi, leaving interstices between them, through which the internal coat is occasionally caused to protrude, in strictures and other obstructions of the urethra. Many of these fasciculi, arise about the neck of the bladder, and ascending upwards, before, behind, and laterally, ter- minate at the superior fundus in the base of the urachus. Within these, which may be considered as the longitudinal fibres of the bladder, there are others forming a thinner lamina, whose course is transverse or oblique : they serve to connect the preceding. As the muscular fibres are collected at the neck of the bladder, and at the urachus, there is, of course, an increased thickness at these points. The Cellular Coat ( Tunica propria) like that of the alimentary * Santorini, Septemd. Tabul. THE BLADDER. 101 canal consists in a close, dense, lamellated, and filamentous cellular tissue, very extensible and difficult to tear. It is impervious to water, adheres closely to the muscular coat without, and to the mucous within, so as to form a strong bond of union between them. It is pervaded by many vessels and nerves, which it conveys to the mucous coat. The Mucous Coat is also called the villous, but is much more smooth than the corresponding one of the stomach. It is white, with a slight tinge of red, and abounds with mucous follicles, which though small and scarcely discernible in a natural state, are rendered very obvious by disease. It stretches with much facility, but like other mucous membranes, does not restore itself fully, and is rather thrown in the contracted state of the bladder, into wrinkles or folds, having a diversified course, and of a fugitive character, as they dis- appear again upon the next distention. It is very vascular. The internal face of this coat presents, at its inferior part, the fol- lowing appearances. 1. The Vesical Triangle ( Trig onus Lieutaudi, Trigone Vesicale ,) is placed immediately behind and below the neck of the bladder, occupying the space between it and the orifices of the ureters. It is an equilateral triangle of an inch in length, its surface is smooth, is not affected very materially in extent either by the dilatation or the contraction of the bladder, and is elevated so as to be sufficiently distinct and well defined. 2. The anterior angle of the triangle looks into the orifice of the urethra, and is generally so elevated that it has obtained the name of Uvula Vesicas; it is, however, simply a projection of the mucous membrane depending upon the subjacent third lobe of the prostate ; which, at this point, is not unfrequently much enlarged in the aged, and then presents a great difficulty in the introduction of a catheter. 3. The Orifices of the ureters form the posterior angles of the triangle, and are contracted somewhat below the size of the canals themselves. They are said by Sir Charles Bell,* to be furnished, each one, with a small fasciculus of muscular fibres, which runs backwards from the orifice of the urethra, just beneath the lateral * Med. Chir. Trans. Vol. iii. Vol II.— 10 102 URINARY ORGANS. margins of the triangle, and, in its contraction, will stretch the ori- fice of the ureter so as to permit an easy passage of the urine into the bladder. The retrogradation of the urine is prevented by the ureter passing obliquely, for six or eight lines, between the muscular and the mucous coat; there is something also in the obliquity and elliptical shape, with a defined edge of the orifice itself which assists in this effect ; as I have ascertained by removing the muscular coat entirely, at this point, and dissecting up the ureter, notwithstanding which, the bladder, when inflated, still retained its contents. Where the ureter penetrates the muscular coat, there is often found a layer of longitudinal muscular fibres ascending and enveloping it for half an inch, or an inch. 4. The Inferior Fundus of the bladder ( Bas-fond of the French) is a depression of the general concavity of the bladder, of about six lines in depth, placed between the base of the vesical triangle and the posterior side of the bladder. In the erect position, calculus, when present, lodges there. 5. The Internal Orifice of the neck of the bladder resembles strongly that of a Florence flask, modified, however, by the projec- tion of the uvula vesicae, which makes it somewhat crescentic below. The neck of the bladder penetrates the prostate gland but, at its commencement, is surrounded by loose cellular tissue contain- ing a very large and abundant plexus of veins.* The internal layer of muscular fibres is here transverse; and they cross and intermix with each other in different directions, forming a close compact tissue, which has the effect of a particular apparatus for retaining the urine, and is called Musculus Sphincter Vesicae Urinariee. Generally, anatomists have not considered this structure as distinct from the muscular coat at large ; but the late Sir Charles Bell, Profes- sor in the University of Edinburgh, whose reputation as an anatomist was well established, gives the following account of it. “ Begin the dissection by taking off' the inner membrane of the bladder from around the orifice of the urethra. A set of fibres will be discovered, on the lower half of the orifice, which, being care- fully dissected, will be found to run in a semicircular form round the urethra. These fibres make a band of about half an inch in * Mascagni, Anat. Univ. Str. Prim. Tab. Spec. Fig. V. THE BLADDER. 103 breadth, particularly strong on the lower part of the opening, and, having mounted a little above the orifice, on each side, they dispose of a portion of their fibres in the substance of the bladder. A smaller and somewhat weaker set of fibres will be seen to complete their course, surrounding the orifice on the upper part; to these sphincter fibres a bridle is joined, which comes from the union of the muscles of the ureters.”* After repeated observations on this point, I have come to the conclusion that Mr. Bell has indicated a real structure ; but my own dissections have resulted as follows: The inferior semicircumference of the neck of the bladder is defined by a thick fasciculus of mus- cular fibre, half an inch wide, running in a transverse direction, and having its ends attached to the lateral lobes of the Prostate Gland? being above the third lobe of the latter. This fasciculus is perfectly distinct from the ordinary muscular fibre of the bladder, and re- sembles in its texture the musculo-fibrous coat of the arteries. The superior semicircumference is also surrounded by a thin layer of muscular fibres of the ordinary kind, forming a broad, thin band of a crescentic shape, the low’er ends of which are insensibly lost in the adjacent muscular coat of the bladder by being spread out. And, lastly, beneath the mucous membrane of the vesical triangle, there is a triangular muscle of the same size as the vesical triangle. Having elongated angles, the anterior angle may be traced to the posterior part of the caput gallinaginis, and the posterior angles to the orifices of the ureters and the adjacent part of the bladder. The texture of this muscle is, also, like that of the musculo-fibrous coat of the arteries. When a bladder is recent, this detail of structure is made out with difficulty : it requires to be previously hardened in spirits of wine.f That a power exists in the neck of the bladder of retaining completely the urine, has been satisfactorily demonstrated to me in a case of fistula in perineo, wffiich was presented to the notice of the late Dr. Physick and myself, some years ago,| as well as in other cases occurring since then. The insertion of the muscle of the vesical triangle into the caput gallinaginis, has a double effect, it by drawing the caput back fills up the front of the neck of the bladder; and by easing the orifices of the ductus ejacu-. * Diseases of the Urethra, &e., p. 10. Lond. 1820. f Anat. Atlas, Fig. 373 from preparations in Anatomical Museum,. 'p Chapman’s Med. and Phys. Journ. 1824. 104 URINARY ORGANS. latorii allows a free exit of semen, while it prevents the latter from retrograding into the bladder. Occasionally there exist on each side of the neck of the bladder, passing from it to the pubes, a muscle of half an inch in breadth, the effect of which is to draw the neck of the bladder towards the symphysis pubis. This, called by some the muscle of Wilson, or the Compressor Urethrae has also an influence in retaining the urine. When it exists in a distinct state it is evidently, the anterior fasci- culus more detached than usual of the Levator Ani; but under ordi- nary circumstances it appears as the anterior margin of that muscle, and therefore does not attract especial attention. As the urethra of the male performs the double office of conducting both semen, and urine, it will be described more properly along with the organs of generation. The urine has a considerable number of constituents, the propor- tion of which varies according to age, health, and other circumstan- ces. Water forms about nine-tenths of it, the remainder is an animal matter insoluble in alcohol; uric and lactic acids; lactate of am- monia; sulphate of potash and of soda; hydrochlorate of soda and pf aminonia ; phosphate of soda pnd of lime ; and: fluate of lime. ORGANS OF GENERATION. CHAPTER I. Of the Organs of Generation in the Male. The Male Organs of Generation consist in the Testicles and in the Penis, with their appendages ; or, in the language of some anato- mists, in the Formative and in the Copulative Organs ; which dis- tinction has been applied to both sexes. SECT. I. — OF THE PENIS.* The Penis, ( Membrum Virile , Mentula y ) from performing the two* offices, one of which is the conducting of urine from the bladder,, and the other the projection of semen into the female, has accord- ingly, a peculiarity of structure, which allows a state of collapse and of erection. Its shape is almost cylindrical, but terminating in front by an obtusely pointed extremity, named Gians. It adheres by its posterior end or root to the bones of the pelvis, at and below the symphysis pubis. It is formed by common integuments, by condensed cellular tissue,, by the Corpus Cavernosum, and by the Corpus Spongiosum. The skin on tire penis is more thin and delicate than it is on most other parts of the body, and is furnished with a considerable number of sebaceous follicles or glands about the root of the organ, with hairs growing from the centre of them. This same skin, in passing. * Anat. Atlas. Fig. 376 to 381, inclusive. 10 * 106 ORGANS OF GENERATION. to the abdomen over the pubes, is somewhat protruded by a subja- cent deposite of fat and cellular matter, causing an appearance cor- responding w’ith the mons veneris of the female ; and is also generally thickly covered with short curly hair, which, as the individual ad- vances in life, proceeds in a pointed direction to the umbilicus. The skin of the penis is connected to the organ by a loose filamentous cellular substance, so that it slides readily backwards and forwards, and by its elasticity is well; suited to the varying states of erection and collapse. At the anterior extremity it is thrown into a dupli- cature or fold, the prepuce, (Prceputium ;) the internal lamina of which being fixed circularly to the penis, some distance back from the point, permits a considerable portion of that extremity of the penis, called the Gians, to project when the prepuce is drawn back. The under middle part of the prepuce is attached to the extremity of the glans by a vertical longitudinal duplicature, called the Frsenum, which extends to the orifice of the urethra, The skin does not actually stop at the circumference of the glans, but is continued smoothly over it, modified, however, so much in its structure, as to be much more adherent, soft, delicate, vascular, and sentient: its, cuticle tlier.e is a thin epithelium, readily separated by maceration. The projecting circular and oblique shoulder of the glans, behind which the skin. becomes firmly joined to the penis, is called the Crown ( Corona Glandis .) The contracted portion, behind the corona, is the Neck ( Colhim .) On the surface of the neck and the posterior face of the corona, the skin is furnished with an abun- dance of small glandular masses or follicles, ( Glandules. Odoriferce Tysoni,) which, secrete the thick white sebaceous matter, (Smegma \ preeputii ,) that accumulates w’hen personal cleanliness is not attend- ed to. The penis, in addition to other modes of attachment to the bones of the pelvis, is fixed by the Ligamentum Suspensorium. The latter is a triangular vertical fibrous lamina, which proceeds dowmwards from the symphysis pubes to the dorsum of the penis; and, accord- ing to Mr. Codes, envelops this organ to the glans, forming its cel- lular coat, and being continued into the fascia superficialis abdo- minis. This cellular coat is found sometimes in no small degree condensed in its texture and fibrous, so that it becomes a sort of fascia. Posteriorly, it is lost insensibly on the fascia of the thighs, covering the adductor muscles. At its origin it is occasionally THE PENIS. 107 furnished with muscular fibres; one strongly marked instance of which has been presented to me in my own dissections. The Corpus Cavernosum of the penis, forms by much the most considerable portion of the whole organ. Externally, it is a white fibrous membrane, of a dense structure, enjoying extensibility and an extreme degree of contractility. This coat of the penis is occa- sionally called its elastic ligament. Its external fibres pass, for the most part, longitudinally, except about the root, where they are blended with the periosteum of the bone, and with the tendons of the muscles. It arises by two conical crura, swollen at their base, from the internal face of the crura of the pubes and ischia, to within a little distance of the anterior part of the tuber ischii. At the lower part of the symphysis pubis these crura join and form a body ; which, when stripped of its connexions, resembles two cylinders united, lying alongside of each other; and which terminate in common, an- teriorly, by a truncated cone, covered obliquely by the glans. At the posterior part of the corpus cavernosum, in its centre, there is a septum, almost complete, also of the same elastic substance, which separates the two halves from each other; but, anteriorly, this septum is more imperfect, having an arrangement like the teeth of a comb, whence the term Septum Pectiniforme has been given it. This sep- tum is continued at its margins into a layer of circular fibres, con- stituting the internal coat of the corpus cavernosum. In this arrange- ment into external longitudinal and internal circular fibres, we see a renewal of the same mechanism which marks the hollow viscera. It is commonly not noticed by anatomists. In the middle of the corpus cavernosum, above, is a longitudinal depression for lodging the veins of the penis, and, in the same man- ner, there is another below, for the corpus spongiosum urethrae. The cavity of this membrane is filled by a spongy tissue, that arises frorn its internal face, and is formed of filaments and little laminae ; they, by crossing each other, make a multitude of cells, which have a perfectly free communication with one another, and generally are somewhat occupied by blood. A fine injection through the artery of the corpus cavernosum will fill these cells and return through the veins ; from which cause the cells may be considered as inter- mediate to the two orders of vessels. This opinion is the more probable from the cells being lined by a thin membrane like the in- 108 ORGANS OF GENERATION. ternal one of the veins, and which is easily seen near the septum by tearing the spongy part from it. The internal cellular structure of the corpus cavernosum is pro- bably formed, almost exclusively, by the internal coat of the dilated veins, partially sustained by the above filamentous and laminated bands, for the purpose of strengthening the arrangement. The ad- hesion of this structure at large to the corpus cavernosum is much weaker than one may suppose, as it is very easy to peel or roll it off' almost without dissection, thus leaving the elastic ligament of the corpus cavernosum perfectly free. In the case of the corpus spon- giosum, the cellular structure, though analogous in texture to the above, does not peel off so easily. The Corpus Spongiosum Urethrae extends from ten or twelve lines behind the junction of the crura of the corpus cavernosum, to the anterior extremity of the penis. Externally, it has a coat resembling that of the corpus cavernosum, except that if is thinner, and in its centre is the canal for the passage of urine. Between the canal and the coat is a spongy structure, much finer than that of the corpus cavernosum, and though the cells communicate freely, still they have the appearance of convoluted veins. The corpus spongiosum is not of equal diameter in its whole course, for its commencement in the perineum, where it is pendulous, is enlarged into what is termed the Bulb; from this it diminishes gradually to the anterior end, where it is again enlarged into the glans penis. Fig. 29. Midler* has made the assertion that there are two modes of arterial termination in this erectile or cel- lular structure of the penis, one by direct connexion with the incipient ramuscles of the veins, and the other, by tufts of cceca bent backwards on them- selves, as here represented, and, which he has named Helicine arteries (Arter. llelicinse. ) Projecting as they do into the * Elem. Physiol, vol. i., p. 252. Lond., 1840. Prof. Valentin (Muller’s Archiv. 1838. p. 182) denies the existence of the arteri® helicin®. According to his observation all the branches of the arteries of the corpus cavernosum, after forming numerous anastomoses terminate in the large veins of the penis. The small arteries run in the centre of the bundles of fibres which lie between tbe veins ; and when these bundles of fibres, or band-like septa, are cut or torn across, they, together with the arterial twigs within them, contract and assume a contorted, sometimes spiral figure. In THE PENIS. 109 venous cells, he declares that though no openings from them can be discovered, yet the latter exist so as to fill the cells in erection. These singular arteries are found principally in the back part of the corpus cavernosum and spongiosum, and are seen after a minute size injection of the arteries of the penis, by washing the size from the cells, when the cells have been filled. The Urethra is a mucous canal, whose length varies according to the degree of erection in the penis, and extends from the neck of the bladder to the extremity of the glans. It is difficult to assign a fixed length to the canal of the urethra, owing to the variable size of the penis in different persons, and in the same individual, depend- ing upon his general vigour and also period of life. The measurements of Professor Pancoast'* in the black and mulatto, show an average of about seven inches from the neck of the bladder to the end of the urethra in the unstretched state, and about an inch more in stretch- ing the organ moderately. It is, however, well known that the sexual organs of the black are larger, both male and female, than of the white. The urethra is curved, and receives in its course the ductus ejaculatorii, the excretory ducts of Couper’s glands, and the mucous lacunse of its own internal membrane. The first part of this canal which traverses the prostate gland is from fifteen to eighteen lines in length, and is called the Prostatic Portion : it is well supported by this body, although its own sides are very thin. On its inferior sur- face is the doubling which constitutes the Verumontanum or Caput Gallinaginis. On either side of the caput gallinaginis the canal of the urethra is depressed into something like an oblong cul-de-sac or narrow trench, where are to be found the lacunae of the prostate gland. Between the Prostate and the Bulb is the membranous part of the urethra, about eight or ten lines long ; it is unprotected, except by this state they form the so-called arteri® helicinse. The fibrous bands which pass inwards between the anastomosing- veins from the external tunic of the corpus cavernosum, consist, according to Prof. Valentin, of tendinous tissue, and give attachment to muscular fibres, similar to those of the intestinal canal, which pass from them to the parietes of the veins. M. Valentin supposes erec- tion to be in a great measure due to the active dilatation of the veins by these muscular fibres ; but the characters on which he founds his belief that the fibres in question are muscular, are not conclusive. * Wistar’s Anat. 8th Edit., vol. ii. p, 170. 110 ORGANS OF GENERATION. a soft covering, which seems in some measure to be a mixture of gelatinous matter and muscular fibre. The former w T as considered by Littre as a glandular body which secreted a viscid humour into the interior of the canal ; the latter, probablv, is the part described by Winslow as the inferior prostatic muscle ; which he asserted to arise on each side of the membranous part of the urethra, and to be inserted into the corresponding branch of the pubes near the sym- physis. The membranous part of the urethra does not get into the end of the bulb but penetrates it from above, half an inch or more occasionally, from its extremity, just below the junction of the crura of the corpus cavernosum. The canal varies in its diameters: at its commencement, which is synonymous with the neck of the bladder, it is large ; it then con- tracts at the back of the caput gallinaginis, and immediately en- larges in the fore part of the prostate, at the sides of the caput. The membranous part is small ; the canal then enlarges in the bulb. In the body of the penis the canal is successively diminished, till it comes almost to the glans, when it is so remarkably enlarged again as to get the name of Fossa Navicularis ; it terminates, finally, by a short vertical slit at the extremity of the glans. The canal of the urethra is formed of a very thin mucous mem- brane, on the outside of which is a dense filamentous cellular sub- stance possessing much extensibility, contractility and elasticity. The mucous membrane has great vascularity, and its veins are so superficial that they frequently bleed freely upon the introduction of an instrument into the bladder, it is also very sensitive. The cel- lular coat on its outside, whereby it adheres to the spongy structure, contracts sometimes in such a manner that circular fasciculated ridges simulating the presence of circular muscular fibres, are seen shining through the mucous coat, though when the mucous coat is peeled off this arrangement disappears. In the whole length of the canal there are two folds or lines, one above, and the other below ; and in the membranous and spongy portions, excepting the fossa navicularis, longitudinal folds of the mucous membrane also exist, which are effaced by distention. The fossa navicularis sometimes exhibits in the contracted penis, hardened in spirits of wine, very superficial folds of the mucous membrane almost transverse, in the narrow depressions between which we see the orifices of very fine mucous follicles. In the upper part of the canal there are a great many mucous « THE PENIS. Ill lacunae ;* * * § Loder has marked about sixty-five : there is one parti- cularly large in the upper surface of the fossa navicularis, which, it is said, has stopped the point of a bougie, and been mistaken for stricture.! Mr. Shaw has described a set of vessels immediately on the out- side of the internal membrane of the urethra ; which when empty, are very similar in appearance to muscular fibres. He says, he has discovered that these vessels form an internal spongy body, which passes down to the membranous part of the urethra, and forms even a small bulb there.! His preparation, being a quicksilver injection of the part, is certainly a very satisfactory demonstration of its exist- ence ; yet in my own observations, where the blow-pipe has been resorted to, it has rather appeared to me to be the cellular membrane connecting the canal of the urethra with the corpus spongiosum. The arteries of the penis come from the internal pudic; some of its veins follow the course of the arteries, and others collect into the two vente dorsales penis; the nerves come from the Superior and Inferior Pudendal. SECT. II. — OF THE MUCOUS GLANDS AND APPARATUS. The Seminal Vesicles§ ( Vesiculce Seminales ) are two convoluted tubes, one on each side, two inches in length, placed on the lower fundus of the bladder, between it and the rectum, and behind the prostate gland. At their anterior extremities they approach very nearly to each other, being only separated by the intervention of the vasa deferentia. They are fixed to the bladder, and surrounded by a thick mass of adipose and cellular matter, with many blood vessels, principally veins, passing through it. When inflated and dried, they present the semblance of cells, but are, in fact, long tubes; which being convoluted, are reduced to the apparent dimensions mentioned. When dissected and * Tabula Anat. t Sir Everard Home formerly communicated to the Royal Society a highly interesting paper on the structure of the lining membrane of the urethra. From his microscopical observations he was induced to think that it is muscular. ! Med. Chir. Trans, vol. X. § Anat. Atlas, Figs. 383, 390, 391, 392._ 112 ORGANS OF GENERATION. stretched out, they are four or five inches long, by three lines in diameter. There are also several pouches on each side of the long tube which increase the number of cells. The convolutions are pre- served by the intermediate cellular tissue. These bodies consist of two coats: an external, which is a condensed fibro-cellular sub- stance; and an internal, which is mucous, being a continuation of the lining membrane of the urethra. The excretory duct of each vesicle is about a line and a half long, when it joins in the sub- stance of the prostate with the vas deferens of the same side; a common canal ( ductus ejaculatonus ) is thus formed, which runs parallel with its fellow, below the urethra.* The Ductus Ejaculatorius is about eight or ten lines long, and opens by an oblong orifice, on the anterior margin of the Caput Gallinaginis; it is larger behind than before, which gives it a conical shape, and allows fluids injected to pass freely from the vas deferens to the vesicula seminalis, and the reverse. The vesiculte are commonly filled by a drab-coloured thick fluid, supposed to be a mixture of the semen, with their own proper se- cretion, though, of this, Mr. Hunterf doubted, inasmuch as he found them equally well filled in cases where the testicle of the corres- ponding side had been lost, and therefore he concluded that they were not indebted to the secretion of the testicle for their contents. The discovery, latterly, of spermatic animalcules in the fluid con- tained after death in the vesiculas is considered now as proof suffi- cient of their being reservoirs of the male semen along with their own secretion, as these animalcules were most probably conveyed there along with the semen. The Prostate Gland ( Glandula Parastata ) is a body about the size and form of a horse chestnut, fixed on the neck of the bladder, and penetrated by the urethra, which traverses it much nearer its superior than its inferior surface. The base of it is turned back- wards, and the point upwards; its inferior surface rests upon the * In a dissection executed at the University by Dr. Joseph Togno, a muscle was found on the inferior surface of the seminal vesicles arising from the pros- tate gland, and inserted into them. This is said to be a common arrangement in some animals. f Observations on the Animal Economy. PROSTATE GLAND. 113 rectum ; it is rendered concave by that circumstance, and its sides, in the distentions of this organ by faeces, are overlapped by it. The Prostate has, posteriorly, a notch in its centre, which divides it into two lateral lobes, and by raising the Vesiculae Seminales, we see where their excretory ducts penetrate the gland, and separate from the body of it, the little tubercle, to which Sir Everard Home* has particularly called the attention of the profession, and considered as a third Lobe ; it being certain that it is frequently the seat of dis- ease and tumefaction. On the under surface of the canal formed in the prostate, by the urethra, is, as mentioned, the oblong elevation called the Verumon- tanum, or Caput Gallinaginis. It commences a little in front of the uvula vesicas, and, being broader and higher behind, comes to a point very gradually before; it is about eight or ten lines long. Along the posterior part of this ridge a long cleft is sometimes found, it being the orifice of a lacuna, first observed by Morgagni ; and in front are the orifices, bordering upon each other, of the ductus ejaeulatorii. Very superficial folds of the lining membrane, some three or four in number, radiate from the anterior end of the caput to the anterior end of the membranous portion of the urethra. The use of the Caput Gallinaginis, as already intimated, is probably to plug the orifice of the urethra at the neck of the bladder, at the moment of ejecting the semen: it being drawn backwards to that effect by the muscle of the vesical triangle. The prostate consists in a condensed, white, extensible, though easily lacerated fibrous cellular tissue, within which are placed a great number of mucous canals, that have from eight to twelve ducts, or, according to Loder, from thirty-two to forty-four, passing obliquely forwards, and terminating in the urethra, as stated, at the sides of the urethral crest, or caput gallinaginis. It is an aggrega- tion of smaller glands, like the mamma or any other composite gland ; the principal ducts are, therefore, formed by the convergence of branches in successive junction. The fluid secreted is thick, ropy, white, and semi-transparent, in a healthy state. The prostate is surrounded by a fibrous capsule, to be described. The lacunae of the third lobe penetrate the coats of the bladder, behind the caput gallinaginis. * Diseases of Prostate. VOL. II.— 11 114 ORGANS OF GENERATION. Of the Glands of Couper . — These glands are also intended for the secretion of mucus, or a fluid very much like it, into the canal of the urethra. They are two in number, one on each side, and are situated in advance of the prostate, between the laminte of the triangular ligament, at the point where the bulb of the urethra ad- heres to it. Commonly, they are about the size of a garden pea, but not unfrequently much smaller, and, in some instances, cannot be found at all, which induced Hiester to declare, that he had searched for them fruitlessly. They are yellowish, hard, and con- sist of several lobules united together. Each one has an excretory duct, that receives readily a bristle, and passes obliquely forwards, between the corpus spongiosum and the canal of the urethra, to ter- minate in an oblique orifice in the latter, about an inch distant from the gland. One or more glands, of the same description, and discovered by Littre, are occasionally found just in front of Couper’s. They also discharge their secretion into the adjacent part of the urethra. In my own dissections I have not met with them. SECT. IIJ. — OF THE TESTICLES.* The Testicles ( Testes , Didymi) are two in number, one for each side of the scrotum. Being the seat of the secretion of sperm or the male prolific liquor, their function is of the first importance in the act of generation. They are of an oblong oval form, somewhat compressed laterally ; and present their edges forward and back- ward. From being suspended near the middle of their posterior edge by the spermatic cord, the upper end points somewhat forward, while the lower one is directed in the same degree backward. They are about an inch and a half long, by one inch in breadth, and eight or nine lines in thickness. They are of equal size generally, but in case of a difference it is in favour of the right ; the latter is also re- markable for being suspended higher than the left, a feature in ancient statuary, so universal, as to prove the vigilance and accuracy of the sculptors of those days, in regard to the proportions and peculiarities of the human form. “Two obvious advantages attend this arrange- ment: one, that of dhe testicles passing each other without col- * Anat. Atlas, Figs. 386 to 395, inclusive. THE TESTICLES. 115 lision when the thighs are brought together ; and another, the facility of keeping the penis to one side, instead of straight forward in the middle line of the body.”* The testicle is enveloped by several tunics; they are the Scrotum, the Dartos, the Tunica Vaginalis, and the Tunica Albuginea. The Scrotum is merely a continuation of the common skin from the inner side of the thighs, the perineum, and the penis, and is common to the two testicles. It is a symmetrical bag, and the two halves are marked off from each other by a middle line or elevation of the skin, called the Raphe, which begins in the perineum at the anus, and, winding around the scrotum, is continued along the under surface of the penis to the prepuce. The skin of the scrotum is thin, darker than elsewhere, but has a thick, strong epidermis; it has many sebaceous follicles in it, and is sparingly furnished with hair. It is very extensible, as manifested in fatigue, and by hydrocele; and maybe contracted again so as to draw the testicles close under the pubes, though for the latter power it principally depends upon the subjacent coat. Its surface is covered with wrinkles, for the most part transverse, and ending at the raphe : they are effaced during its great dis- tentions in hernia and dropsy, and then it has a smooth shining surface. The Dartos is placed within the scrotum, and forms two distinct sacs or tunics, one for each testicle. It arises from the inferior margins of the crura of the ischia and of the pubes, and lines the scrotum till it reaches the raphe ; it is then reflected upwards to form the partition between the testicles, ( septum scroti ,) and ter- minates at the corpus spongiosum urethra. This membrane, ac- cording to the observations of MM. Chaussier, Lobstein, and Breschet,f does not exist in the scrotum till the descent of the tes- ticle, and then appears to be an expansion of the gubernaculum testis. It receives a considerable number of blood vessels, which, owing to the thinness of the skin, may be seen in the living body, ramify- ing through its substance: its general appearance is, therefore, * Sir A. Cooper on the Testis. 1830. f Dictionnaire des Sciences Med., tome viii. 116 ORGANS OF GENERATION. reddish. It is destitute of fat, and consists in long fibres much matted together, and passing in every direction: they are easily separated by distention with air or water, and by slight maceration. Its powers of contraction are exceedingly well marked upon the application of cold to the scrotum, from which cause it has been considered by many anatomists as muscular: the only distinct evi- dence, however, which I have met with of a resemblance to the latter, has been found generally on its posterior face, near the perineum * From its equivocal character, J. F. Meckel has very ingeniously suggested that it forms the transition from cellular to muscular tissue, and that there exists between it and other muscles the same relation that there is between the muscles of the superior and of the inferior orders of animals. Among the latter, the fibrous structure is indistinctly marked, and is masked by gelatine, an ele- ment of the cellular tissue ; which envelops and conceals the fibrine, an element of the muscular tissue. The fibres of the cremaster muscle, which are next in order, form a very imperfect covering to the testicle, and belong rather to the spermatic cord : what remains to be said concerning them will be more properly introduced into the account of the latter. The cellular substance that connects the dartos and the cremaster with the tunica vaginalis forms a compact and perfect lamina, sometimes spoken of as the Tunica Vaginalis Communis Testis. There is one for each testicle, which it surrounds entirely, as well as its chord, and connects the chord to the margin of the external abdominal ring, as stated in the account of the latter. At its upper end it is continuous with the cellular substance that unites the peri- toneum to the parietes of the abdomen, as may be proved by in- flating it, when the air will penetrate accordingly through the ab- dominal canal. The Peritestis, or Tunica Vaginalis, was originally a process of peritoneum, communicating with the cavity of the latter through the abdominal canal ; but in the adult, it appears as a complete and distinct sac. As it is very rigidly comparable to a double night-cap drawn over the head, we accordingly find that the testi- * Since the first edition, I have dissected one subject, (January, 1830,) where the fibres were evidently muscular, though interwoven. THE TESTICLES. 117 cle, along with the epididymis is pushed into it from behind. That portion of the tunica vaginalis which is in contact with the testicle, or rather with the tunica albuginea, adheres so closely that it can- not be separated, except very partially and in shreds; but it may be detached easily from the epididymis, with the convolutions of which it is in immediate contact. This sac is longer and larger than the testicle itself, from which cause it ascends for several lines above the superior end of the gland, and the free part hangs loosely about it. Its cavity may, with but little force, be injected so as to hold an ounce or two of fluid. This membrane is smooth and polished on the surface forming its cavity, and contains a small quantity of serous halitus, which allows the opposed surfaces to glide freely upon one another. Its exterior connexion with the dartos is so slight that it may be with- drawn without dissection, with the exception of an adhesion at the lower end of the testis arising from the remains of the guberna- culum : in such case, however, it still continues to be invested by the tunica vaginalis communis, from which it can only be removed by a special dissection. The Tunica Albuginea is the proper coat of the testicle; is in im- mediate contact with its glandular structure, and serves to maintain its shape, as well as to protect it from pressure. From its interna^ surface proceed many membranous, horizontal fibres, which form partial partitions of its cavity ( Septulce Testis) and incline towards its posterior part, where they terminate in a longitudinal projection, called Corpus Highmorianum. The latter is of a prismatic shape, somewhat broader above than below, and is of but little consequence, except that it was once erroneously supposed to be a sinus, into which the seminiferous tubes discharged. Sir Astley Cooper pro- poses to call this the mediastinum testis, and considers the Corpus Highmorianum as being formed by an inflection of the tunica albu- ginea. The Septulae Testis, he asserts, really envelop the semini- ferous tubes, by forming bags which support, confine, protect, and nourish the tubular structure of the testis.* The albuginea is per- forated by several foramina along its posterior margin, where there is a deficiency of tunica vaginalis, for the passing of excretory ducts and blood vessels. * Observations, &c. on the Testis, p. 14. London, 1830. 11 * 118 ORGANS OF GENERATION. This membrane is dense, strong, white, and fibrous, resembling in structure the tunica sclerotica of the eye, and the dura mater of the brain. Sir A. Cooper considers the tunica albuginea as con- sisting of two layers which can be readily separated by dissection, excepting in front; the outer layer is the fibrous one, while the in- ternal one, which he calls Tunica Vasculosa, has the spermatic arteries and veins ramifying upon it. They are rendered very dis- tinct from each other by a minute injection.* Of the Minute Structure of the Testicle .] — The glandular portion of the testicle consists in a congeries of zig-zag tubes ( Tubuli Semi- niferi) which are collected into lobules. One, two, or more tubes constitute a lobule, and the lobules are kept apart by the septulae testis. These lobules are of a conoidal shape, having their points towards the posterior middle line of the Testis and their bases rounded, they diverge from the corpus Highmorianum, so as to fill up the cavity of the tunica albuginea. The entire number of tubes amounts to 300, according to Dr. Munro; with an aggregate length of 520S feet, and the diameter of each one does not exceed one two- hundreth part of an inch, and its length is somewhat short of seven- teen and a-half feet. Their number is, according to Krause, from 404 to 4S4. Lauth has stated the number of tubes to be 840, and the length of each to be about twenty-seven inches, which corres- ponds nearer with my own observations, and makes an aggregate length of about one-third of that represented by Dr. Munro. These tubes form convolutions or hanks, the threads of which are serpen- tine, very much like the thread of a ravelled stocking; and are held together by a delicate cellular substance easily softened by macera- tion. Each tube forms of itself a hank, which is kept distinct from the adjacent ones by the septulce or processes of the albuginea, and may be easily picked out from them. Their extreme tenuity and delicacy of structure cause them, when well macerated, drawn out with a pin, and then suspended in water, to resemble a tangled skein of fine silk. The tubuli seminiferi finally terminate in some straight tubes, called the Vasa Recta, which unite near the middle back part of the testicle in a somewhat complicated arrangement, obtaining the * Observations, &c. on the Testis, p. 14. London. 1830. f Hunter, Med. Comment, p. 1. 1777. Albinus, Acad. Annot. Lib. ii. Loder, Tab. Anat. — Ruysch,Thes.Anat. iv. Haller, Op. Min. tom. ii. — Alex. Munro. de Testibus, Ed. 1755. THE TESTICLES. 119 name of the Rete Vasculosum Testis. This Rete Vasculosum is placed in the Corpus Highmorianum and from it there proceed from twelve to eighteen ducts ( Vasa Efferentia) which go upwards and backwards through the corpus Highmorianum and the tunica albu- ginea. Each of these vasa efferentia is then convoluted upon itself into a conical body, called Conus Vasculosus, which presents its base backwards. Each conus, at its base, has its tube entering successively into the tube of which the Epididymis is- formed. Notwithstanding the extreme tenuity of these several arrange- ments in the excretory ducts of the testicle, they may be entirely filled with quicksilver from the vas deferens; but the task is one of great difficulty, and rarely succeeds. The anterior ends of the tubuli seminiferi would seem from the observations of Lauth and Krause,* to have different modes of ter- minating, some end by cceca, others by a loop, and others by anas- tomosis with contiguous tubes. These anastomoses according to Lauth, are most frequent towards the base of the lobules, and occur there about every three inches. At the other end of the seminal tubes, several unite into one, to form a vas rectum, of which there are at least twenty, and with a diameter larger than the tubuli seminiferi. The vasa recta are a line or two long, they then are reduced into from seven to thirteen trunks, forming what is called the Rete Vasculosum Testis, which is distinguished by the waving course of its trunks, and by their fre- quent anastomoses with each other. According to Lauth, the number of vasa efferentia varies, in diffe- rent subjects, from nine to thirty, and when the entire length of each one is extended it measures eight inches ; of course, including the conus Vasculosus. The Epididymis is the prismatic arch which rests vertically on the back of the testicle, and adheres to it by the reflection of the tunica vaginalis. It is enlarged at both ends, the upper of which, being formed by the Coni Vasculosi is called the Globus Major, and the lower enlargement is the Globus Minor. It is made of a single convoluted tube, of the fourth of a line in diameter. After this tube has got to the lower end of the globus minor it becomes less con- voluted, enlarges, turns upwards on the inner side of the epididymis, and obtains the name of Vas Deferens, which before it reaches the top of the epididymis has become perfectly straight, or almost so. * Muller, loc. cit. p. 499. 120 ORGANS OF GENERATION. The average length of the canal of the Epididymis is about twenty- one feet, and the coni vasculosi discharge into it at intervals of three inches and a-quarter.* There is a blind duct, ( Vasculum Aberrans ) which begins at the top of the epididymis and terminates below ; the base of it is up- wards, and the other end discharges into the lower end of the ca- nal of the epididymis, where the latter makes its turn into the vas deferens. Its length varies from one and a half to fourteen inches. Sometimes there are several. The use is unknown. The tubuli seminiferi form a system of closed tubes, with the ex- ception of the posterior end, which discharges into the Rete Testis. Their diameter being about fifteen times greater than that of the arteries ramifying upon them, the conclusion is drawn that their whole internal surface executes the seminiferous secretion. Of the Spermatic Chord. The Spermatic Chord is a fasciculus of about half an inch in dia- meter, which may be felt very readily through the skin of the scro- tum, passing from the upper end of the testicle to the external ab- dominal ring. It is formed by the Vas Deferens ; the Spermatic Artery and Veins ; the Lymphatics of the Testicle ; and the Nerves ; all being covered in by the Tunica Vaginalis Communis, and by the Cremaster Muscle. The Cremaster Muscle , also called the tunica elythroides,f being derived from the internal oblique and the transverse muscle of the abdomen,^: forms a very complete envelope to the chord from the abdominal ring to the testicle. But when it reaches the latter its fibres spread out and become indistinct upon the tunica vaginalis communis, as they there consist in small, pale, scattered fasciculi ; many of which terminate insensibly, while others form on the front of the tunica vaginalis loops, having their convexities downwards. This muscle draws the testicle upwards, an action very different from the corrugation of the scrotum. The Vas Deferens , or the proper excretory duct of the testicle, is a white tube of about a line and a half in diameter, and has a car- # Lauth, see Muller. f Em/7$5v, a sheath, f See Abdominal Muscles THE TESTICLES. 121 tilaginous feel. Its parietes are thick, as its cavity will not receive a body larger than a bristle, without being put upon the stretch. It traverses a long space, and in doing so, first passes at the back of the chord from its commencement to the internal abdominal ring: having reached the latter, it then abandons the spermatic artery and vein, and dipping into the pelvis, by the side of the bladder, goes between the lower fundus of the latter and the ureter. It then con- verges towards its fellow, along the under extremity of the bladder, at the inner margin of the vesicula seminalis of the same side, and finally terminates in the urethra near the neck of the bladder, by forming the Ductus Ejaculatorius with the assistance of the duct of the adjoining vesicula seminalis. About two and a half inches from its termination, it enlarges and becomes somewhat tortuous. This duct consists of two coats : the external one is hard, compact, and occasionally fibres are seen in it ; but its structure is not very evident, and is peculiar. The internal is a mucous membrane. For the description of the remaining portions of the chord, see Spermatic Artery, Vein, Lymphatics, and Plexus of Nerves. The Testicles undergo a remarkable change in their position, from the earliest development of their rudiments to the perfect foetal state. They are not formed in the scrotum, but in the abdomen just below the kidneys ; from which position they are gradually trans- ferred. About the middle of the third month of gestation they are two lines long, and placed behind the peritoneum, to which they loosely adhere. The vas deferens then, instead of rising up on the side of the epididymis, goes straight down into the pelvis. At this period may be seen the gubernaculum testis, discovered by J. Hunter,* which becomes more distinct in a few w r eeks afterwards, and assumes a triangular appearance. This gubernaculum has the office of drawing the testicle down into the scrotum ; its point com- mences in the upper part of the latter, somewhat below the external abdominal ring; it passes through the abdominal canal, ascends upon the iliacus interims muscle, and is attached by its base to the inferior end of the testicle. In front of the gubernaculum, a pro- cess, or small pouch of peritoneum, passes through the abdominal canal to the upper part of the scrotum. By the contraction of the gubernaculum, the testicle is brought, about the seventh or eighth * Med. Comment. Lond. 1777. 122 ORGANS OF GENERATION. month, into the scrotum, by sliding down behind the pouch. The lower end of the pouch, at which the testicle is finally arrested, be- comes the tunica vaginalis testis. As soon as the testicle has reached the scrotum, the neck of the pouch has a tendency to close and to become obliterated, which is commonly accomplished at the period of birth ; yet it sometimes remains open for a longer time and becomes the occasion of con- genital hernia. Very generally at birth, the orifice of the pouch will receive the end of a probe to the depth of a line or two ; but all below is perfectly closed, and has its structure so condensed and altered, that no one, from a view of it alone, would suppose that the cavity of the tunica vaginalis had ever communicated with that of the peritoneum.* SECT. IV. — OF THE MUSCLES AND FASCIJE OF THE PERINEUM, t Perineal Fascia . The Perineal Fascia is placed just beneath the skin of the peri- neum, and covers the muscles. It is spread over nearly all the space between the anus and the posterior margin of the scrotum, and between the rami of the pubes and the ischia on each side : it is very firmly fixed to these bones, and is gradually blended with the cellular substance of the posterior part of the scrotum. This fascia is rather thin, but, in case of a rupture of the posterior part of the urethra, prevents the urine from showing itself in the perineum, and drives it into the cellular structure of the scrotum. In abscesses of the perineum, it also prevents the fluctuation from being very evident. * The explanations and anatomy of this process have been treated at large in the following- works : Girardi, Tabul. II. adj. Septemd. Tab. Santorini. J. Hunter, Observations on certain parts of the Animal Economy. W. Hunter, Med. Commentaries. Edwardi Standifort, Opusc. Anat. Wrisberg. Comment. Medic. Physiolog., &e. f Anat. Atlas, Figs. 384, 385, MUSCLES AND FASCIiE OF THE PERINEUM. 123 The Musculus Erector Penis. It is so situated, as to cover the whole of the crus of the penis which is not in contact with the bony margin of the pelvis. It arises, therefore, tendinous and fleshy, from the anterior part of the tuber ischii; its fleshy fibres adhere to the internal and external mar- gins of the ramus of the ischium, and of the pubes, and proceed upwards: just before the union of the crura of the penis, they end in a flat tendon which is lost on the side of the corpus cavernosum of the penis.* Its use is not well understood. The Musculus Accelerator Urince, Lies on the bulb and back part of the corpus spongiosum urethrae ; it is a thin muscle, consisting of oblique fibres. It arises by a pointed production from the side of the body of the penis ; its origin is continued obliquely across the inferior surface of the crus penis, where the latter begins to form the body of the penis. It arises, also, for an inch from the inner side of the ramus of the pubes, between the crus penis and the triangular ligament of the urethra. The muscles of the opposite sides are inserted into one another by a white line, which marks the middle of the bulb of the urethra ; and by a point, into the anterior extremity of the sphincter ani, where they are joined by the transversi perinei. V In order to see the origin of these muscles very distinctly, sepa- rate them from each other in the middle line, and dissect them from the corpus spongiosum. Cut transversely through the corpus spongiosum about three inches before the triangular ligament, and dissect it clearly from the corpus cavernosum, turning it down- wards so that it may hang by the membranous part of the urethra. By putting the two acceleratores on the stretch, it will be seen that besides the origins mentioned, they arise, also, from each other by a tendinous membrane that is interposed between the corpus spon- giosum and cavernosum ; so that they literally surround the back * The late Dr. Lawrence informed me that he had frequently found mus- cular fibres between the bone and the crus penis. 124 ORGANS OF GENERATION. part of the urethra, constituting a complete sphincter muscle for it. This account of the accelerator urinse being peculiar to my- self, is adopted from a strong analogy between it and the sphincter vaginae. The two muscles are considered by M. Chaussier as forming but one : in that case its origin will be reversed, and commence in the middle line of the perineum instead of terminating there. As this muscle, and the erector penis, touch by their contiguous faces, it is difficult to get into the membranous part of the urethra in lith- otomy without cutting through the muscular fibres of one or the other. It propels the urine and semen forward. The Musculus Transversalis Perinei, As its name implies, passes directly across the perineum ; it arises from the inner side of the ischium, just at the origin of the erec- tor penis, and is inserted where the sphincter ani and acceleratores urinae join. I have observed that when the lower part of the accelerator was extended much below its usual line, and strongly developed, that the transversalis was very irregular in its origin and course ; consist- ing frequently of a few fibres which did not deserve the name of a distinct muscle, and lying almost unappropriated in the adipose matter of the part. Occasionally, a fasciculus of muscular fibres exists, called, by Albinus, Transversus Perinei Alter, which arises in front of the transversalis : it seems generally to be a loose fasciculus of the ac- celerator urinse muscle, and is inserted into the perineal junction just behind it. The use of these muscles seems to be to contribute to fix the bulb of the urethra. The Musculus Sphincter Ani , Consists in a plane an inch thick, of elliptical fibres immediately beneath the skin of the anus, and which surrounds the latter in order MUSCLES AND FASCIiE OF THE PERINEUM. 125 to keep it closed. The long diameter of the ellipsis is extended from the coccyx towards the symphysis pubes, and has its angles very much elongated ; the anterior may be traced terminating insen- sibly in the posterior face of the scrotum. It has two fixed points, the last bone of the os coccygis behind, and the perineal union of the other muscles in front ; its lateral diameter occupies about one-half of the space between the tuberosities of the ischia, and it is in the middle of this space. This muscle, besides the fixed points men- tioned, has at its anterior and posterior ends, many fibres ending simply in the subcutaneous cellular substance, and which are much more superficial than the fixed points. Besides closing the orifice of the rectum it will draw the bulb of the urethra backwards, or the point of the os coccygis for- wards. The Musculus Coccygeus , Belongs to the interior of the pelvis. It arises by a small, ten- dinous and fleshy beginning, from the spine of the ischium, and lying on the anterior face of the anterior sacro-sciatic ligament, it is inserted into the side of the last bone of the sacrum, and of all those of the os coccygis. It draws the os coccygis forwards. It frequently happens that there is on each side a small fasciculus of muscle arising from the inferior bone of the sacrum in front, and inserted into the bones of the coccyx ; it is called Sacro-Coccygeus. . A large quantity of adipose and cellular matter exists on the side of the rectum, between it and the parietes of the pelvis, concealing the perineal surface of the levatores ani muscles. The Musculus Levator Ani , Arises, fleshy, from the back of the pubes near its symphysis, and from near the superior margin of the foramen thyroideum above the obturator interims muscle. It also arises from the aponeurosis pelvica, where this membrane is extended as a thickened semi-lunar chord from the superior margin of the thyroid foramen towards the spinous process of the os ischium. This second part of the origin of the le- Vol. II. — 12 126 ORGANS OF GENERATION. vator ani is defectively described in most books on anatomy. It is then seen to cross obliquely, as far as the spine of the ischium, that portion of the obturator internus which arises from the plane of the ischium. From this extensive origin the fibres converge and descend back- wards, and have three distinct places of insertion; the posterior fibres are inserted into the last two bones of the os coccygis ; the middle, and by far the greater number, are inserted into the semi- circumference of the rectum between its longitudinal fibres and the circular fibres of the sphincter ani ; and, finally, the most anterior fibres pass obliquely downwards and backwards on the side of the vesical end of the membranous part of the urethra, and on the side of the prostate gland, and are inserted into the common place of junction of the perineal muscles. The fore part of this muscle is by some of the English anatomists, called the Compressor Urethrae.* The Triangular Ligament of the Urethra , Is a membrane which fills up the space below the symphysis of the pubes, and answers there as a septum between the perineum and the pelvis : when closely examined, it is seen to connect itself to the internal edges of the rami of the pubes and ischia on the inner pos- terior sides of the crura penis as far down as the beginning of the latter. At its lower edge its ligamentous character is not so well defined. On its anterior surface is the bulb of the urethra, and just at the extremity of the latter, enclosed by the ligament, and adhering to it, are Couper’s Glands. In contact with it behind, and ad- hering, is the prostate gland, covered by its fibrous capsule, which is a continuation of the pelvic aponeurosis over it. A perforation exists in it, through which passes the membranous part of the ure- thra. This opening is not very apparent, in consequence of its edges being continued a little distance on the canal ; but by de- taching them the whole becomes well defined. The relative situation of the bulb and of the membranous part of the urethra is such, that the former goes towards the anus, while the latter passes upwards towards the neck of the bladder ; they conse- quently, form a considerable angle with each other. The mem- * Wilson’s Anatomy, p. 198. MUSCLES AND FASCIiE OF THE PERINEUM. 127 branous part of the urethra is much the deepest, the recollection of which, is all-important in lithotomy, as it teaches us to avoid the one, and to cut into the other. It may also be observed, that the hole in the triangular ligament is an inch below the symphysis pubis. By removing the upper corner of the triangular ligament, we are made acquainted with another just behind it, which is totally distinct. This ligament is half an inch broad, is thick and strong, particularly at its lower edge, and is very firmly attached laterally to each of the ossa pubis, just below the symphysis : it is a continuation of the liga- mentous union of the symphysis pubis. Mr. Colies calls it pubic ligament w T ith great propriety. I would suggest, as somewhat more expressive, the term Inter-Pubic Ligament ;* as it serves to distin- guish it from another called Pubic, which is above the pubes, and described in the account of the recti abdominis muscles. The breadth of this having been stated at half an inch, it is obvious that the hole in the triangular ligament is half an inch below its lower edge. Pelvic Fascia. The Pelvic Fascia ( Aponeurosis Pelvica ) connects the bladder to the sides of the pelvis. “ This fascia descends from the ileo-pecti- neal line to about midway in the depth of the pelvis ; here it is re- flected from the surface of the muscle, (the Levator Ani ,) and applies itself to the prostate gland and bladder on the body of which it is ultimately lost. At the angle of its reflection, this fascia appears par- ticularly strong and white, but becomes more weak and thin as it lines the muscle and covers the bladder. In tracing this membrane it will be seen that from the pubes just below the symphysis, a point- ed production of it, constituting its anterior margin, is fixed into the side of the neck of the bladder. This pointed production on each side is called, by most anatomists, the anterior ligaments of the bladder. Between them, just beneath the symphysis of the pubes, a pouch large enough to receive the end of the finger, is formed by the union of the fasciae of the two sides : this pouch connects the middle anterior part of the neck of the bladder to the lower margin of the symphysis pubis. ”f This fascia adheres closely to the periosteum of the pubes, between the upper margin of the thyroid foramen and the crista of the pubes ; * See Symphysis Pubis. f Codes’ Surgical Anatomy. 128 FEMALE ORGANS OF GENERATION. about the middle third of the linea innominata it is obviously a con- tinuous membrane with the iliac fascia which covers the iliacus in- terims muscle ; but behind this, again, it arises from the remaining third of the linea innominata. The portion of this fascia which Mr. Colies speaks of as parti- cularly strong and white, forms a bow,, the concavity of which looks upwards, one end of the bow being fastened to the pubes above the foramen thyroideum, and the other end to the ischium above its spine. The perineal surface of this bow is an important point of the origin of the levator ani. Above the bow this fascia is very thin, for the fibres of the obturator interims can be readily seen through it. At the bow the fascia divides into two laminae; one pursuing its course to the bladder and rectum, the other covers the lower part of the obturator internus muscle, and thereby constitutes the obtu- rator fascia. The levator ani is interposed between these two laminae. The aponeurosis pelvica also forms a bow or semi-lunar edge in front of the sacral nerves. The triangular ligament and this fascia are so identified in forming the capsule of the prostate, that the capsule in description, may be referred either to the one or the other, or to both, according to the fancy of the describer. CHAPTER II. Of the Organs of Generation in the Female.* The Copulative Organs in the female are, the Vulva and the Vagina; the Generative are the Uterus and the Ovaria. SECT. I. — OF THE VULVA. The term Vulva is applied to the most superficial of the copulative organs, and consist in the Mons Veneris, the Labia Externa, the Labia Interna, the Clitoris, the Vestibulum, the Orificium Urethrae, the Fourchette, and the Fossa Navicularis. Anat. Atlas, Fig. 39G to 4Q3, inclusive. THE VULVA. 129 The Mons Veneris is the protuberance on the fore part of the pubes. Its size varies considerably, according to the state of obesity of the subject, in consequence of its being formed by a deposite of fat between the skin and the bone : in corpulent women it is very large and prominent, whereas, in such as are much emaciated, it simply describes the outline of the bones. The skin, there, is abun- dantly furnished with its peculiar glands, seated in the cellular texture beneath it, and about the size and shape of millet seed. At the age of puberty a growth of hair takes place upon it, which is not so long as the correspondent growth upon men, and is not so much disposed to spread itself over the lower part of the abdomen as life advances. In women who have abused coition, it is said that these hairs become much curled. The Labia Externa are a continuation of the mons veneris down- wards in the form of an oblong eminence on either side. Their elevation is produced in the same way by a deposite of fat beneath the skin. They are somewhat broader and more prominent above than below. On the side which is next to the thigh, the integu- ment is common skin, sparingly covered with hair; but on the other face it is a mucous membrane, being a continuation of that of the vagina. The skin here, as well as at the commencement of every mucous membrane, is insensibly changed into the latter. They have many sebaceous and perspiratory glands externally, and mu- cous glands internally, upon them. Much cellular membrane, like that of the scrotum, is found in their interior structure; whereby they enjoy great extensibility in order to favour the dilatation of the parts in parturition. The rima which exists between them is the Fissura Vulvee of authors, and is about twice the length of the orifice of the vagina; this arrangement of it gives increased facility to the expulsion of the foetus. The Fourchette or Frenulum Vulvse, is situated at the posterior commissure of the labia externa, and is a thin, narrow transverse duplicature of skin ; which, owing to its weakness, is most fre- quently ruptured at the first act of parturition, and then disappears. The Clitoris bears, in some respects, a resemblance to the penis of the male, but is by no means so large. It is situated immediately below the symphysis pubis, and consists in a cylindrical body of three or four lines in diameter, with two crura. The body is an 12 * 1-30 FEMALE ORGANS OF GENERATION. inch long; the crura are likewise of the same length, and arising from the internal face of the crura of the pubes, unite beneath the symphysis so as to form the body. The body is not straight, but has the anterior half bent downwards and forwards. The exterior covering, or capsule of the clitoris, in its texture, resembles the elastic ligamentous membrane of the corpus cavernosum penis ; and is, moreover, filled within by a similar cavernous or cellular struc- ture, which is divided into two equal parts by a septum pectiniforme, and is susceptible of distention during sexual excitement. The clitoris is supplied also with blood vessels and nerves like the penis, and is held up to the under part of the symphysis pubis by a sus- pensory ligament. The anterior extremity of the body of the clitoris is found in the ritna or fissura vulvae, about an inch below the upper commissure of the labia externa. It projects somewhat, and bears a general resemblance in shape with the end of the penis, whence its name of glans clitoridis; but it has not the same organization, excepting the delicacy, the extreme sensibility, and the vascularity of the skin which covers it. The clitoris has no corpus spongiosum, neither is it concerned, like the penis, in conveying the urine from the blad- der. Its glans is covered by a doubling of skin called the prepuce, and is likewise furnished with the gland ulae Tysoni, from which is discharged a smegna, or sebaceous fluid, as in the male. The pre- puce does not furnish a regular well defined fraenum. The Erector Clitoridis muscle corresponds with the erector penis. It arises from the ascending ramus of the ischium, and, covering the inferior face of the crus clitoridis, runs as far forwards as the commencement of the body. The Labia Interna, or Nymphae, are two duplicatures of the mucous membrane of the vulva, which pass down, one on each side, from the clitoris. The prepuce of the latter terminates, on either side, in the labia; while the latter are continued upwards, by a narrow process, to the under surface of the glans clitoridis. They arise all along their base, from the internal sides of the labia externa, or majora; and being wider in the middle than elsewhere, they terminate insensibly about half-way down the orifice of the vagina. Between the laminae of each one is placed a vascular cellular substance, susceptible of distention and of partial erection during sexual excitement. In young subjects, their vascularity THE VULVA. 131 i / communicates a vermilion tinge, which is lost and becomes brown- ish in the progress of life. As they are effaced during parturition, their chief use seems to be as a provision for the great distention of the vulva, which then occurs. The labia interna are about half an inch broad in the natural state, and do not project obviously beyond the labia externa, except in cases of extreme emaciation, where the prominence of the latter has been destroyed by a removal of its fat. They are, however, very subject, as the individual becomes old, to a pointed elongation, in- creasing their breadth to an inch, or an inch and a-half; and to be- come thickened and indurated. A tribe of Hottentots, the Boschis- mans, living near the Cape of Good Hope, are uniformly subject to this enlargement; which, for a long time, was represented, by travellers, as an organ superadded to what is common in the human species. The Vestibulum is a depression of twelve or fifteen lines long between the labia interna ; it is bounded above by the clitoris, and below by the orifice of the vagina. It is abundantly furnished with mucous lacunae. The Urethra of the female has its external orifice ( Orificium Urethra ) in the inferior part of the vestibulum, about one inch below the glans clitoridis, and is generally marked by a slight rising, which is easily distinguished by the sensation of touch alone ; its margin is often bounded by a little caruncle on each side.* The urethra itself is an inch long, larger and much more dilatable than that of the male, its course is obliquely downwards and forwards from the neck of the bladder; passing under the symphysis of the pubes, and being slightly curved from that cause. It consists of two membranes, a lining and an external one. The lining membrane is a continuation of that of the bladder; it is thrown into several longitudinal folds, and has many mucous folli- cles in it. The external coat of the urethra consists of condensed laminated cellular membrane, having a strong affinity with mus- cular fibre: the principal direction of the fibres is transverse, form-- * Professor Pancoast considers the urethra of the young female to have its orifice on a level with the anterior face of the Symph. Pubis, whereas, in such as have borne many children it is behind the pubes. . Yvistars AnaL. vol. ii. p._ 182. Phil. 183,9. ; 132 FEMALE ORGANS OF GENERATION. ing a cylindrical body of half an inch in its transverse diameter, and which has given the idea of the existence of a prostate gland in the female: the lower and lateral surfaces of this cylinder are in contact with the vagina, forming a protuberance into its cavity; and the upper surface is firmly connected to the triangular liga- ment of the pubes. Immediately behind the neck of the bladder, we find the vesical triangle with its muscle, as in the male, except- ing that the anterior angle of it goes to the anterior end of the urethra. The Fossa Navicularis is that portion of the rima vulvse which is below the vestibulum, and anterior to the orifice of the vagina. SECT. II. — OF THE VAGINA. The vagina is a thin membranous canal which leads from the vulva to the uterus. It is from four to six inches in length, differ- ing according to age and pregnancy, and being much shorter in women who have borne children than in virgins. It is placed be- tween the bladder in front, and the rectum behind, being flattened by them so as to bring its anterior and posterior surfaces into con- tact. Its anterior extremity is the smallest of the two; and pre- sents its greatest diameter vertically, while that of the posterior is transverse. As it follows accurately the central line of the pelvis, it is, consequently, curved with its concavity forwards. Its ante- rior parietes are shorter than the posterior, both from the smaller depth of the pelvis in this direction, and from the mode of con- nexion with the uterus. The vagina is formed by two tunics; a fibrous and a mucous one. The first is external, of a light red colour, highly elastic, and seems to consist of condensed cellular membrane, the fibres of which are much intermixed, and pass in every direction. It is vascular, and immediately adjacent to the large venous sinuses of the pelvis. The mucous membrane being a continuation of that of the vulva, is at and near its anterior orifice of a vermillion tinge; while, posteriorly, it is grayish and frequently spotted, so as to give it a marbled appearance: its thickness diminishes as it recedes from the external orifice; and upon being floated in water, many mucous lucunse are observable upon it. The internal surface of the vagina is commonly covered with THE VAGINA. 133 the mucus which comes from its lacunae. On the anterior or pubic portion, it is divided longitudinally by a middle ridge, which commences by a sort of tubercle just below the orifice of the urethra, and proceeds backwards, becoming indistinct as it ap- proaches the uterus. Transverse ridges formed in the same way by folds of the mucous membrane, arise from the sides of the last at its anterior portion, and give a roughness to that part of the va- gina. The inferior side, or that next to the rectum, has the same kind of arrangement of the mucous membrane, but not os distinct. • In a majority of subjects, the uterine half of the vagina is perfectly smooth, but the rule does not always hold. The internal membrane of the vagina is covered by its epithelium, the scales or cells of which are detached and found in the secretion of mucus. The Corpus Spongiosum Vaginae is an erectile tissue, like that of the penis, and closely resembles in structure the corpus spongiosum urethrae. It is placed at the anterior end of the vagina, on its outer circumference, just below the clitoris, and at the base of the labia minora or interna. It is an inch broad, and a line or two thick, ad- heres closely to the fibrous coat of the vagina, and extends around the superior semicircumference of the orifice, but not around the in- ferior. It is frequently called Plexus Retiformis. The Sphincter Vaginas Muscle surrounds the anterior orifice of the vagina, and covers the plexus retiformis. It is about an inch and a quarter wide, and arising from the body of the clitoris and the crus of the pubes, behind the crus of the clitoris, passes back- wards and downwards to be inserted into the dense, white sub- stance, in the centre of the perineum, common to these muscles, the transversi perinei and the anterior point of the sphincter ani. There is a strong analogy between it and the accelerator urinre of the male. The Transversus Perinei of the female, has the same circum- stances of origin and insertion as in the male, but is not quite so strong. On each side of the orifice of the vagina, near its middle, is fre- quently found a mucous gland, the size of a garden pea : it corre- sponds with Couper’s gland of the male subject. 134 FEMALE ORGANS OF GENERATION. The Hymen,* one of the attributes of the virgin state, is placed at the anterior orifice of the vagina for the purpose of closing it, and commonly remains until it is ruptured by violence. In all cases except where there is an unnatural adhesion, it leaves a small orifice for the passage of mucus and of menstrual blood. In my own ob- servations, I have found it most frequently crescentic, the convexity of the crescent presenting downwards, and the horns upwards ; but in some cases it is to one side. Next in frequency to the lunated is 'die circular shape, where it surrounds completely the orifice and leaves a hole in its own centre. There are some other varieties, such as its being fleshy, fasciculated, unequally divided into two portions, and so on, which are narrated by different writers. Being simply a duplicature of the mucous membrane, it is generally so weak as to be ruptured at the first act of copulation; or even from slighter causes during infancy : but occasionally, it becomes thickened, and so strong as to require division with the knife. Upon the rupture of the hymen, its place is indicated in subsequent life by from two to six small tubercles, called Carunculae Myrtiformes, which are its remains. The peritoneum, in descending from the uterus, anteriorly, touches the top of the vagina for a little distance, and is then re- flected to the bladder, but posteriorly, almost the upper half of the vagina has a peritoneal coat before this membrane is reflected to the rectum. The attachment of the vagina to the bladder is strong and close just above the urethra, but its connexion with the rectum is by rather loose cellular substance. SECT. m. — OF THE UTERUS, AND ITS APPENDAGES. The Uterus, or Womb, is a compressed pyriform body, the larger end of which stands upwards, while the lower is directed down- wards, and is attached to the vagina. f Unimpregnated, it is two * J. G. Tolber, Diss. de Variet. Hymen. — Haller, Icon. Anat. Fasc. i. — Albin. Acad. Annot. Lib. iv. — Santorini, Septemd. Tab. f This is commonly represented by anatomists in their plates and descrip- tions as the position of the womb ; it is, however more so in advanced preg- nancy than when empty. In my dissections generally, I have found the pos- terior face of the womb downwards, reposing upon the concavity of the rectum, and the os tineas obliquely forwards; this position being probably produced by UTERUS, AND ITS APPENDAGES. 135 and a half inches long, and one and a half in diameter at its widest part. The posterior face is very convex, while the anterior is al- most fiat, or very slightly convex. It is about one inch in thick- ness. It is divided by anatomists into fundus, body, and neck. The fundus is formed by its superior extremity, and comprises the space between the orifices of the Fallopian tubes : the neck is the lower cylindrical portion, of about an inch in length ; and the body is the part intermediate to the two. On the exterior circumference of the uterus, there are no marks or lines distinguishing these several * portions, from each other. The uterus, being destined to lodge the foetus from a short pe- riod after conception to the moment of birth, has a cavity ready for its reception. The shape of this cavity bears some general, but not a rigid resemblance to that of the organ itself, and it is so much flattened as to have its anterior and posterior parietes in con- tact, or nearly so. The cavity of the body is an equilateral trian- gle of eight or ten lines in diameter ; the sides of the triangle are bent inwards in parabolic curves, in such a way as to present their convexities to the cavity of the uterus: this of course, occasions an apparent elongation of the angles. The inferior angle is continued into the cavity of the neck, while the two superior run into their respective Fallopian tubes. From this arrangement it happens that the parietes of the uterus are only three lines thick on the angles of the triangular cavity, while at the middle they are from four to six lines. The cavity of the neck has not its anterior and poste- rior sides so near together as those of the body; and is rather cy- lindrical, being smaller, however, at the upper and lower ends than in the middle. This arrangement gives to its sides a paraboloid curvature which presents its convexity outwards, differing in that respect from the corresponding curvature in the cavity of the body. The cavity of the neck terminates in the vagina by an orifice the superincumbence of the small intestines, and, especially, when the blad- der is empty. When the latter is full, the peritoneum is reflected from the centre of the uterus to the posterior face of the bladder, and its traction has the effect of erecting the uterus in part, from its nearly horizontal direction. In the dissection of a female, April 9, 1838, aged eighteen, who died from an affec- tion of the brain, there being every evidence of soundness in the genital organs, 1 found the rectum making a curve to the right side of the inferior part of the sacrum, and the body of the womb, reposing in the concavity of the latter. 136 FEMALE ORGANS OF GENERATION. about the size of a small writing-quill, but ovoidal, and presenting its long diameter transversely. This orifice is the Os Tincse, or Orificium Externum Uteri ; frequently, without apparent disease, I have seen it conoidal, with its base, half an inch in diameter, pre- senting downwards. The upper orifice whereby the cavity of the neck communicates with that of the body is not subject to such fluctuations in size: it is occasionally called Orificium Internum Uteri, and is generally somewhat larger than a small writing-quill. The os tincse is bounded before and behind by the lips of the uterus, formed by the projection of the neck into the vagina. For the most part the anterior lip is directly continuous with the anterior side of the vagina: so that its projection is very inconsiderable, and, indeed, not appreciable to the finger: at the same time, this lip is rather thicker than the posterior. The projection of the latter, on the contrary, is always well marked, because the vagina, instead of being inserted into its ridge, is joined to the posterior surface of its base. The cavity of the uterus is lined by a very thin mucous mem- brane, a continuation of that of the vagina. This membrane is of a light pink colour, which changes to a Vermillion during the pe- riod of menstruation; it is said to be furnished with villosities, which, though seen with difficulty in the usual way, may be ren- dered apparent, by floating the uterus in water; and it adheres so closely to the substance of the uterus, that it forms an inseparable portion of it, which can neither be dissected nor macerated off’ en- tirely, as in the case of other mucous membranes. This membrane is smoothly laid upon the cavity of the body, and gives it a polished shining surface. On the cavity of the neck, it is wrinkled along the anterior and the posterior parts; there being a longitudinal line running along the centre, and on each side of this line transverse or oblique elevations or duplicatures. This ar- rangement presents an arborescent appearance, technically called the arbor vitae. In the interstices of these duplicatures there are some small mucous glands or lacuna3, which as their orifices are exposed to obliteration from inflammation or some other irritation, become distended into small spherical sacs by the accumulation of their habitual secretion. Naboth, from seeing them in this state, mistook them for eggs, or the rudiments of the foetus, and the error has been commemorated by their being called Ovula Na- THE VAGINA. 137 bothi. This membrane is covered by an epithelium which is vibra- tile to the middle of the neck, and afterwards pavement-like. The uterus is covered completely by the peritoneum; in the re. flection of the latter, from the rectum to the bladder, it adheres to the uterus by a subjacent cellular substance, which allows it to be dissected off without difficulty. The same duplicature of peritoneum which encloses the uterus, is also reflected from each of its lateral margins, by their whole length to the corresponding side of the lesser pelvis, and forms the Lateral or the Broad Ligaments, ( Ligamenta Later alia, Lata.) The peritoneum in passing from the uterus for- wards to the bladder, forms on each side, a duplicature, not very distinct, and depending, in a measure, upon the state of the bladder; this constitutes the Anterior Ligament. The same membrane in passing from the back of the uterus to the rectum, and in covering the posterior superior end of the vagina, also forms, on each side, a duplicature, denominated the Posterior Ligament; it is always better seen than the anterior. Muscular fibres are said to be found, occasionally, between the laminae of these several duplicatures, run- ning in the direction of the latter;* they have not been presented to me in such a way as to arrest my attention. The broad ligaments, along with the uterus, form a transverse septum, passing from one side of the pelvis to the other ; and con- tain, between their laminae, the arteries and the veins which belon°- to the uterus and ovaries. Besides the duplicatures of peritoneum, the uterus is retained in its position by the Ligamenta Rotunda, one on each side. These round ligaments arise from the side of the uterus, a little below the insertion of the Fallopian Tube, and going between the laminae of the broad ligament, reach, finally, the internal abdominal ring : they then traverse the abdominal canal and the external ring after the manner precisely of the spermatic chord, and terminate by several fasciculi in the fatty cellular matter of the mons veneris and of the labia majora. The round ligaments are rather smaller in the middle than at either extremity ; they consist of a condensed cellular or fibrous structure, and have many blood vessels in them. It has been asserted,! that they contain strongly marked muscular fibres ; some of which come from the uterus, and others from the broad * J. F. Meckel* vel. ii. p. C05. Vol. II.— 13 f J. F. Meckel, loc. cit. 138 FEMALE ORGANS OF GENERATION. muscles of the abdomen. No evidence of this fact has as yet been presented to me, though I do not deny it; and, indeed, I think it probable, that such fibres may be developed there during gestation. The texture of the uterus is very compact, and of a cartilaginous feel ; it is composed of fibrous matter, intermixed with a great many blood vessels. In regard to its fibrous structure, there is no subject in anatomy upon which opinions are more divided, or more authori- tative and numerous on both sides of the question. Some deny its existence at any period, while others admit it as a constant condi- tion : others, again, limit its duration only to the period of pregnancy. Without dwelling on the value of the several doctrines, and the means and observations tending to support them, it may be suffi- cient here to mention that the structure of the uterus takes on very important and strongly marked changes, in passing from the unim- pregnated state to that of advanced gestation. In the first the fibres look ligamentous and pass in every direction, but so as to permit the uterus to be lacerated more readily from the circumference to ihe centre than in any other course : it, indeed manifests an indis- position to be torn in a laminated manner. The fibres, moreover, break off short, are separated by the blood vessels, and seem 1o con- tain, in their interstices, something like fibrine. In the impregnated state, on the contrary, the vessels being im- mensely increased in size, the laminated structure becomes very evident, and submits readily to the tearing of one layer from the other : these laminae consist of fibres, which are principally parallel with each other. The muscular nature of these fibres seems to be sufficiently proved, by their powerful contraction in the expulsion of the foetus, and on being irritated by the introduction of the hand. They are, however, not red like other muscles, but of a very light colour as those of the bladder and intestines ; and are collected into fasciculi of peculiar flatness and looseness. The development of this muscular structure is not, always, limited to the pregnant state, but is disposed to manifest itself on many occasions which produce an increased size in the uterus. This fact was first exemplified to me in a small scirrhus of a virgin uterus, presented by Dr. Hugh L. Ilodge,* and has been still farther confirmed in a case, where the scirrhus was five or six inches in diameter ; also in a virgin uterus, very much enlarged from scirrhus, presented by Professor * Now Professor of Obstetrics in the University of Pennsylvania.- UTERUS, AND ITS APPENDAGES. 139 Charles D. Meigs.* A similar fact has been noticed by Lobstein, of Strasburg, where the tumour was also steatomatous. The fibres of the uterus, examined near the term of pregnancy, consist in two planes separated by the large bloodvessels; one within and the other without. These layers are readily divisible into subordinate laminae, intermixed with one another but yet to a considerable extent separable. The external layer is thicker than the internal, and both have an increased thickness at the fundus: while they are much diminished, and indeed indistinct, at the cervix. The fibres generally are either circular or longitudinal, but many of them are oblique. The exterior surface of the external plane, is composed principally of longitudinal fibres, within which are the circular. The inner plane, on the contrary, has the circular fibres external, and the longitudinal internal. In both planes the circular fibres are more abundant at the fundus, and the longitudinal upon the body of the uterus ; but, generally speaking, there are collec- tively more longitudinal than circular fibres. Of the Fallopian Tubes. The Fallopian tubes ( Tubes Fallopiance ) are two membranous canals, one on either side, fixed in the superior margin of the broad ligament of the uterus. They serve to conduct the rudiments of the embryo from the ovarium into the uterus. They are about four inches long, and extend from the upper angle of the uterine cavity to the side of the pelvis: their outer extremity is loose, and hangs upon the posterior face of the broad ligament over the ovarium, consequently inclines downwards, thereby forming an angle with the other portion. At their uterine extremities the Fallopian tubes are about the size of the vas deferens, resemble it strongly, and scarcely admit a hog’s bristle; but having proceeded about one-half of their length, they begin to enlarge, and continue to do so rapidly for an inch, until they reach the size of a writing-quill; they then contract again somewhat, and immediately afterwards expand into a broad trumpet- * Of the Jefferson Med. College. 140 FEMALE ORGANS OF GENERATION. shaped mouth. The latter has an oblique orifice, the edge of which is extremely irregular, by being resolved into a number of ragged fringe-like processes, of unequal size and length; and which, as a whole, are called Corpus Fimbriatum, or Morsus Diaboli. One of the longest of these processes adheres to the external end of the ovarium. The Fallopian tube is covered by the peritoneum, and consists of two coats: the external is fibrous, and bears sufficient resemblance to the structure of the uterus to be considered a continuation of it; the internal is mucous, and is likewise a continuation of the corres- ponding one of the uterus. The external end of the tube, which is called Pavilion by the French anatomists, is flaccid, thin, and gene- rally in a collapsed state, as it is formed solely by the mucous mem- brane, assisted by the peritoneum, neither of which furnishes re- sistance sufficient to keep it expanded ; but, as many blood vessels enter into its composition, their turgescence, in sexual excitement, probably communicates a certain degree of erection. Mr. Grainger has ascertained that the Fallopian tube presents a difference in the structure of its mucous membrane, the part next the uterus, not being so vascular as the other part: moreover, the latter presents a complex arrangement in the form of folds or valves running in a longitudinal direction and plaited. We are left to infer that the difference is more conspicuous shortly after concep- tion.* There is some similitude in this arrangement with the ovi- ducts of birds, one part of which secretes the albumen of the egg, and another part, the shell; and it may be in the human subject, also, that the two parts execute different offices in the perfection of the ovum. Of the Ovaries . The Ovaries, ( Ovaria , Testes Muliebres,) two in number, one on either side, are situated on the posterior face of the broad ligaments by a duplicature of which they are surrounded, and are twelve or fifteen lines below the Fallopian tubes. Their shape is that of a compressed ovoid, about half the size of the male testicle: their long diameter is horizontal ; they are suspended from the broad ligament rather by the edge than by the flat surface, so that they project, and * Muller’s Physiol., p. 1563. THE OVARIES. 141 are to a considerable degree pendulous. Their distance from the uterus varies from an inch to an inch and a-half, and from the in- ternal end of each one there proceeds a small vascular fibrous cord, the Ligament of the Ovarium, which is inserted into the uterus, somewhat below the origin of the Fallopian tube. From their being the seat of conception, they have, in the youth- ful and healthy female, a pliancy and succulency, indicative of their state of preparation for the act; but in advanced life they diminish much in volume and become hard and dry. Their surface, origi- nally smooth or slightly embossed, is subsequently rendered uneven, by repeated acts of conception, leaving on it a number of cicatrices or small stellated fissures. They are of a light pink colour. Within the peritoneal coat is another, the Tunica Albuginea, of a strong, compact, fibrous texture, like the same coat of the testicle, and sending inwards many processes. The structure of the ovarium is as follows : But few females, of those presented in our dissecting rooms, have the part in a state fit for study, owing to age, disease, or excessive sexual indulgence : my best opportunities have been derived from post mortem exami- nations, in private, of individuals of from fourteen to twenty, where the virgin state had been preserved. When an ovarium of the latter kind can be got, by cutting through the tunica albuginea simply, and then tearing open the organ, it will be found to consist of a spongy fibrous tissue, abundantly furnished with blood vessels from the spermatic artery and vein. In this spongy tissue, called Stroma,* are from fifteen to twenty spherical bodies, the Graafian vesicles, ( Ovula Graajiana ,) according to the commonly received opinion ; but in an ovarium exhibited to me by the late Dr. John Hopkinson, there were thirty-six distinct vesicles. They vary in size from half a line to three lines in diameter ; the larger ones are nearer the surface, and from having caused the absorption of the tunica albuginea, may sometimes be seen through the peritoneal coat, and give to the surface of the ovarium an embossed condition. The vesicles contain a transparent fluid having within it the rudi- ments of the embryo. As the vesicles are evolved they advance from the centre to the circumference. Their parietes are thin, trans- parent, and have creeping through them minute arterial and venous By von Baer, from its being a bed (stratum.) 13 * 142 FEMALE ORGANS OF GENERATION. ramifications. The bed of the ovarium in which a vesicle reposes is called the calyx. To Von Baer* belongs the merit of discerning first the ovulum of man and of mammalia in the Graafian vesicle. The Ovulum occu- pies but a very small part of the cavity of the Graafian vesicle, the remainder being filled with an albuminous fluid in which micro- scopic granules float. By discharging the fluid from a Graafian vesicle, the Ovulum can with a simple lens be detected in a globu- lar form and floating in this fluid. By flattening out this little globe under a thin plate of glass, and then examining with a compound microscope, it will be seen that it consists of a transparent membrane containing a Vitellus or yolk made of granules or cells and fat glo- bules. Within the above vitelline membrane is placed the Germinal vesi- cle of the human subject,! being about V j of a line in diameter. This vesicle has also the germinative spot, macula germinativa of Wagner, which is from the jis to tnta of a line in diameter. The Ovula Graafiana seldom project much on the surface of the ovarium in the human subject; but in other animals, as the common hen, they, upon being developed, stand out so much as to resemble a cluster of berries each attached by its pedicle, and surrounded by its two appropriate sacs. These sacs constitute what are called the capsule of the ovum or the ovisac. Upon the inner surface of this capsule, according to the observation of Schwann, is to be found a layer of epithelial cells in the different classes of animals, as for ex- ample, in the ovicapsules of fish, and in the Graafian vesicles or ovules of mammalia. The existence of these epithelial cells is con- sidered as proof positive of the sameness of the membrane in what- ever animals it may be examined ; and, therefore that the ovicapsules of oviparous animals are identical with the Graafian vesicles or ovula of mammalia. The stages of development in an egg are, therefore, simply the expression of what occurs also in a Graafian vesicle. Within the ovicapsule of Birds is the yolk (vitellus) surrounded by its membrane called vitelline, which being at first in contact with the capsule, is afterwards separated from it in many animals by a well marked and large interval. The yolk is formed of fine cells con- taining granules and oil globules. * Muller, p. 14G9. f Discovered by Coste in 1834, and more distinctly explored by Valentine and Bernhardt. Muller, p. 1471. THE OVARIES. 143 In the substance of the yolk is the vesicle of Purkinje, or the Ger- minal vesicle. This vesicle contains a transparent fluid, and has on it a nucleus, called the macula germinativa. This vesicle in the fully formed ova of the oviparous vertebrata is imbedded in a disk- shaped layer of granular substance, called the germ disk. The ger- minal vesicle is finally lost by commingling with the granular matter of the germ disk, in which the first rudiments of the embryo are formed. Upon the ovum leaving the ovarium in a bird it has to pass through the oviduct, and in doing so receives as a deposite upon it the white or albumen, and subsequently the shell which is also due to the se- cretory action of the oviduct.* The analogy is thus seen to be striking between the evolution of a common egg and the ovule of the human subject, found in the Graafian vesicle. A very remarkable point, mentioned by Carus, is that all the essential parts of the ovulum can be detected in the ovary of the mature embryo of the human subject or of mammiferous animals, hence the preparation for a new generation seems to begin at a very early period of life. When an ovulum is discharged from a Graafian vesicle the latter and the surrounding calyx open in a stellated line: this line of de- hiscence or gaping is in birds preceded by a whitish arched band called the stigma, which indicates the place for the escape of the ovum. There appears to be some analogy in this with the spon- taneous fissure of the rind or bur of certain fruits. Upon the escape of the contents of the Graafian vesicle the latter is first filled with coagulating lymph or blood, or rather undergoes a pullulation from its interior surface, so as to form a body called the Corpus Luteum, which being after a while absorbed the vesicle collapses and shrivels, and the stigma then remains permanently as a stellated cicatrix. Sometimes the entire surface of the ovarium is marked with those stigmata. The phenomena attending the formation of the corpus luteum have elicited great interest, of late years, and many very scientific * A satisfactory explanation of the above process, according to Wagner and others, is found in Muller’s Physiol., p. 1468. London, 1842. 144 LACTIFEROUS GLANDS. observations have been made on the subject by BischofF,* * * § Wagner, f Huschke,j; and others. The Organs of Generation in the female are supplied with blood principally from the internal pudic and other branches of the hypo- gastric artery: the corresponding veins run into the hypogastric. Their nerves come from the sacral and from the hypogastric plexus. The arteries of the Ovarium come from the Spermatic and from the uterine. Former anatomists considered the spermatic to be the prin- cipal one — the opinion is now changing in favour of the branch of the uterine. The spermatic veins discharge as in the male sub- ject. The Bladder and the Rectum, with unimportant exceptions, are the same in both sexes. The Levator Ani, the Coccygeus, and the Sphincter Ani, are also similar. The pelvic aponeurosis in the female, besides connecting the bladder to the sides of the pelvis, is attached to the anterior part of the vagina. The triangular liga- ment of the urethra also exists, but under circumstances somewhat; modified by the close connexion of the urethra with the vagina. CHAPTER III. Of the Lactiferous Glands, or Brcasts.§ The Breasts ( Mammae ) of the female are intended for the secre-. tion of milk, and thereby to maintain the connexion between mother and infant for some time after the uterine life of the latter is passed. All mammiferous animals exercise this function : in birds there is a sort of substitute for it, in the changes which take place in the first stomach or crop during incubation. In the male subject there is, * Trait, de Develop, de L. Homme. Paris, 1843. f Elements of Human Physiol. Part I. London, 1841. 4 Traite de Splanch- Paris, 1845. § Anat. Atlas, Figs. 404 to 410, inclusive. LACTIFEROUS GLANDS. 145 also, a small glandular body on each side, which has the same or- ganization as in the female, but is in miniature, and always remains in a collapsed state, with some rare exceptions ; when it has been known to expand in volume, and to furnish a secretion, as in the female.* The Breasts are two in number, one on either side; they are situated on the same level, in front of the peetoralis major muscle, and between the arm-pit and the sternum. They are hemispherical, and have their base united to the muscle by a thin lamina of loose, extensible, cellular substance, containing, even in corpulent women, but little fat. The skin which covers the front of this gland is very fine and thin, so that the blood which circulates in its veins maybe readily seen. Between the skin and the front surface of the gland, there is a considerable thickness of cellular adipose matter, which, from its superabundance in some individuals, gives to them an ap- pearance of having the glands enormously enlarged. There is, however, a great variety in the size of the glandular structure itself; for, in females who are youthful and giving suck, they are much larger than in such as have passed the period of child-bearing, and whose health is impaired. When all the fatty matter has been re- moved from a breast, and it is permitted to repose upon a table, its hemispherical shape disappears, and it then seems rather a flattened circular disk, of from four to five inches in diameter. The mamma is of a very light pink colour ; and though very flac- cid and yielding on being handled, its texture is actually extremely tough, and is cut only by much force. With the exception of bone, * In a male patient, a resident in the Philadelphia Alms House, the pheno- menon of a full evolution of the glandular structure in both breasts is mani- fested. The individual (James McIntyre) is forty five years of age; the breasts are as large as those of a nursing woman ; but the nipples are not proportionately evolved. Though his frame is robust, and well set, the voice is feminine ; his external organs of generation are about the size of those of a boy of fourteen ot fifteen. Thinking that there might be an internal state approaching to herma- phrodism, he informed me, on inquiring, that in earlier life be had the common inclinations for the female. He also informed me that this unusual develop- ment took place seven or eight years ago, owing to an excessive salivation; but, as he has a reserve on the subject, this statement may, probably, be re- ceived with some qualifications. I have also seen a second case, in which the voice is weak and feminine, but the genital organs have not been examined. — July, 1826. 146 LACTIFEROUS GLANDS. it dulls a knife sooner than any other tissue of the body. Its grosser arrangement consists in lobes of different sizes, united in such a way by cellular texture, that, though they can be pulled somewhat apart, they cannot be entirely separated without injury. These lobes, when examined through the skin, give to the gland a knotted feel, and are sometimes partially affected by inflammation, so as to be- come still more distinct. The lobes are composed of Lobuli, which are resolvable by maceration and particular modes of treatment, into small graniform masses (acini) about the size of millet seed, and which contain the ultimate glandular arrangement. The acini them- selves consist of very small oblong vesicles, united by cellular substance, and by the common blood vessels ; and are said to be very apparent by the aid of a microscope in a lactescent gland.* These vesicles (Cellulae Lactiferee) have a diameter from ten to thirty- five times greater than that of the smallest capillary vessel of the body,f or according to Krause from the 1-27 to the 1-14 of a line. These vesicles terminate by large openings into the incipient ex- tremities of the lactiferous ducts, having no particular conduit as in the liver, the pancreas and the parotid. Each vesicle is surrounded by a fine close vascular net-work, which is displayed upon its walls, but according to the opinion of the day does not discharge into it. The Excretory Ducts (Ductus Galadophori , Ladiferi ) of this gland are numerous.^ They are of an arborescent shape, and begin by very fine extremities or ramuscules in the acini ; the ramuscules from several acini coalesce into a larger branch ; several branches unite to form one still larger, and so on, successively, until a lactiferous trunk, constituting as it were, the body of the tree, is formed by this assemblage. These trunks vary considerably in size, according to the number of tributary branches, and having got towards the centre of the gland near the nipple, from two to four of them, according to Cuboli, run into a common tube or root, called a Lactiferous * Marjolin, Manual D’Anat. J. F. Meckel, Manual D’Anat. f Muller, loc. cit. p. 488. X Alex. Kolpin, Dis. Inaug. de Struc. Mam. Cubolo, Append, ad Sep- temd. Tab. Santorini. Girardi, Append, ad. Septemd. Tab. Santorini. LACTIFEROUS GLANDS. 147 Sinus. These Sinuses are in all about fifteen : they are only a few lines long, and differ in size ; some not being larger than one lacti- ferous duct, while others have a diameter of from two to three lines. The sinus at the end next to the nipple terminates in a sort of rounded cul-de-sac ; but from the extremity of the sac a conoidal tube arises which runs through the nipple, and conducts the milk : the point of this tube is very fine, and ends on the top of the nipple. This tube, from its shape, is suited to the retention of milk ; in ad- dition to which, it is sometimes dilated in the middle; is curved when the nipple is not in a state of erection or stretched out, and terminates by an external orifice, which is so small as to be seen with difficulty by the naked eye. The excretory ducts of the breast, under which term maybe com- prehended the lactiferous ducts, the sinuses, and the conoidal tubes in the nipple, are formed by a soft, thin, and semi-transparent mem- brane, very capable of extension and of contraction. The trunks generally go deeply through the substance of the gland, and are tor- tuous, but do not anastomose laterally with one another ; whence it happens that the lobes and lobules of the gland are arranged into sections, each of which has its appropriate excretory duct. In order to make a complete injection of the gland, each sinus must be sepa- rately injected through its conoidal tube. This rule is not of uni- versal application, as in some experiments performed by the elder Meckel upon women advanced in pregnancy and during lactation, he succeeded in forcing mercury through one sinus, by its ramifica- tions, into those of another : this route was supposed to have been through the finest extremities of the ducts. The whole gland itself may, however, from the infrequency of this circumstance, and from the difficulties and partial condition of these anastomoses, rather be considered as a congeries of smaller glands kept distinct by the in- terposition of cellular substance between their lobes ; but joined, in one respect, by having the terminations of their excretory tubes col- lected into one bunch in the nipple. This latter circumstance seems to be only a provision for the more convenient sucking of the infant. The excretory ducts are no where furnished with valves, which accounts for the facility with which they may be injected backwards from the nipple. An opinion was entertained by Haller, and by other anatomists after him, that some of these ducts originate in the 14S LACTIFEROUS GLANDS. surrounding cellular substance, but this has been refuted by the re- searches of Cubolo. Some anatomists have thought that there is a direct communication between the ends of the lactiferous tubes and the arteries, veins, and lymphatics. Mascagni, after a very success- lul injection of the gland, whereby its vesicles were filled with quick- silver, not meeting with such an occurrence, was induced to think that when the communication did happen, it was produced by rupture. Terminal follicles of Mammary gland, with their secreting cells, a, a ,• — b, b, the nuclei. Terminal extremities of milk-duct in follicles ; from a mercurial injec- tion, by Sir A. Cooper; enlarged four times. The membrane of the lactiferous canals is somewhat yellow, and upon a transverse section of the gland may be distinguished by its colour. It is covered by epithelial cells, which are almost every where pavement like, according to Pappenheim ; upon their removal he found transverse elastic fibres, covered with longitudinal fibres and numerous cellular fibres, but no muscular. The Areola , In virgins is a rose-coloured circle, which surrounds the base of the papilla or nipple. In women who have borne children, or in those whose age is advanced, it becomes of a dark brown. The skin of the areola is extremely delicate, and on its surface, particu- larly in pregnant or nursing females there are from four to ten tuber- cles, which sometimes form a regular circle near its circumference, and in other subjects are irregularly distributed. Each of these tubercles has near its summit three or four foramina, which are the orifices of the excretory ducts of a little gland forming the tubercle. The areola consists of a spongy tissue beneath which there is no fat ; AREOLA. 149 it is susceptible of distention during lactation, or from particular ex- citement. The greater number of anatomists have considered these tuber- cles as intended only for the secretion of an unctuous fluid which lubricates the areola and nipple, and protects them from excoriation by the sucking of the infant. It is said, however,* that when some time has elapsed after a repast, or when there has been a long inter- val to the nursing of the child, milk flows from them abundantly ; but that in reverse circumstances a transparent, limpid fluid is dis- tilled in small drops ; all of which would tend to prove that they are of the same nature with the mammae themselves, being only smaller. In addition to them, it is said that the areola and the nipple are furnished with a great number of sebaceous glands, which do not elevate themselves above the surface, and which may be found on and near the tubercles. The Papilla , Is the truncated cone in the centre of the mamma, of the same colour with the areola, and surrounded by it. The lactiferous tubes terminate on its extremity. It is collapsed and in a very pliable state for the most part, but when excited it swells, becomes more prominent, and of a deeper colour. Its skin is rough, and provided with numerous and very small papillae. Its internal structure con- sists of the extremities of the lactiferous tubes united by condensed cellular membrane. The mamma is supplied with blood from the external thoracic, ^tercostal, and the internal mammary arteries. Its veins attend their respective arteries. The nerves come from the axillary plexus and from the intercostals. The lymphatics run into the internal mammary, intercostal, and axillary trunks. Among the anomalies affecting this gland is the existence of a supernumerary nipple — but sometimes there is a second gland entire on one or both sides, and commonly placed below the normal one. * J. F. Meckel. Vol. II.— 14 BOOR VII OF THE ORGANS OF RESPIRATION. The Organs of Respiration are the Larynx, the Trachea, and the Lungs. CHAPTER I. Of tlie Larynx.* The Larynx is an irregular cartilaginous tube that forms the upper extremity of the windpipe. It is situated immediately below the os hyoides and the root of the tongue, where it may be felt readily through the integuments, and by its prominence contributes to the outline of the neck. Its position is such, that it is bounded behind by the pharynx, which is interposed between it and the vertebrae of the neck; and laterally by the primitive carotid arteries and the in- ternal jugular veins. It gives passage to the air which is inhaled into the lungs or exhaled from them, and also contributes essentially to the production of the voice. Its special use, on the latter oc- casion, has induced some anatomists to give it a description apart from that of the other organs of respiration ; but as the function of voice is subordinate to that of respiration, I have preferred an ob- servance of its most natural and local connexions. Five distinct cartilages form the skeleton of this structure : the os * Anat. Atlas, Figs. 411 to 424, inclusive. 152 ORGANS OF RESPIRATION. hyoides, which is common to it and to the root of the tongue, also contributes to its superior part, in a manner which will lie presently mentioned. The cartilages are one Thyroid, one Cricoid, one Epiglottis, and two Arytenoid. The Thyroid Cartilage ( Cartilage Thyroidea) is the largest of the five, and being placed about one inch below the os hyoides, pro- duces in the upper part of the neck the prominence called Pomum Adami. It consists in two lateral halves, which in most individuals are. perfectly symmetrical, and are continuous with each other on the middle line of the body. These two sides form at their line of junc- tion an angle projecting forwards, and resembling that of the canal or hydraulic gate : the superior part of the angle is more prominent than the inferior; particularly in the male subject. The sides of this body lean outwards, by which its transverse diameter above is increased. The angle is terminated above by a deep notch, from which the superior margin begins to form a curvature, on either side, like the letter S; the inferior margin is also somewhat curved, but to a smaller degree. The posterior margin of each half is nearly straight, but is elongated above, with the aid of the upper margin into a long process, the Cornu Majus; and below with the aid of the inferior margin, into another process not so long, Cornu Minus. The internal surface of each half of the thyroid cartilage is flat; but the exterior surface is slightly marked by the sterno-thyroid and the thyreo-hyoid muscles. The Cricoid Cartilage ( Cartilago Cricoidea ) is placed below the thyroid, and is the base of the larynx. It is an oval ring, of an un- equal thickness and breadth. Its inferior margin is nearly straight and horizontal, and is con- nected to the first ring of the trachea ; it is also thinner than the superior: the latter is very oblique, and rises from before backwards and upwards so abruptly, that the breadth of the cricoid cartilage behind becomes three times as great as it is in front, under the in- ferior margin of the thyroid cartilage. The superior margin has on each side, behind, a little head, or convexity, which receives the base of the corresponding arytenoid cartilage, and forms with it a ball and socket joint. The interior surface of the cricoid cartilage is smooth, and co- THE LARYNX. 153 vered by the lining membrane of the larynx. Its exterior surface is flattened behind on each side, by the posterior crico arytenoid mus- cles ; it is marked also laterally by other muscles, and by the infe- rior cornu of the thyroid cartilage. The cricoid cartilage is embraced by the inferior margin of the thyroid, but in such a way that a triangular interval is left in front between the two cartilages. The Arytenoid Cartilages ( Cartilagines Jirytcenoidece ) resemble triangular pyramids curved backwards, and are about six lines long. They are placed on the upper margin of the cricoid cartilage be- hind. The anterior face of each is uneven, and divided into two concavities ; the posterior face forms a single cylindrical concavity ; and the internal face, by which it approximates its fellow, is nearly flat. When joined together, the two cartilages resemble the mouth or spout of a pitcher, from whence their name. Their bases are hollowed into a small glenoid cavity, for articulating with the cricoid cartilage. A synovial capsule is reflected over the articulation, between the arytenoid and the cricoid cartilage : this capsule is strengthened by a few scattered ligamentous fibres. The Epiglottis Cartilage ( Epiglottis ) is situated on the posterior face of the base of the os hyoides, being enclosed partially by the two sides of the thyroid cartilage. Its general form is that of an oval disk ; the upper margin of it is thin and rounded, partially curled forwards, and the lower part is elongated into a pedicle which adheres to the entering angle of the thyroid cartilage. Its lateral margin is attached by a- thin elastic membrane to the entire length of the upper thyreo arytenoid ligament. Its surfaces, though nearly flat, are not fully so ; for, anteriorly, it forms a cylindrical convexity, and posteriorly, a cylindrical con- cavity, from side to side. When nicely stripped of its. covering, a. number of very small foramina is seen to exist in it, which are considered to give passage principally to the ducts of muciparous glands. Its connexions, aided by its natural elasticity, keep it in a vertical attitude behind the base of the tongue ; its rounded margin is elevated above the. latter, and overlooks it. In addition to the preceding cartilages, there are always two, and 14 * 154 ORGANS OF RESPIRATION. sometimes four others. On the top of each arytenoid is to be found one, (Corniculum Laryngis;) it is somewhat triangular and elongated: its inferior face is attached by a few ligamentous fibres to the end of the arytenoid ; it is included in the soft parts, and is very move- able. 'fhe others, when they exist, which is rare, are found on the margin of the glottis, in the duplicating of the membrane which is extended from the side of the epiglottis, to the tip of the arytenoid cartilage. From the whole superior margin of the thyroid cartilage included between its greater cornua, there proceeds upwards a thin lamina of somewhat condensed cellular substance, which is attached to the inner margin of the base and of the cornua of the os hyoides their Avhole length. It fills completely the space between the os hyoides and the thyroid cartilage. This membrane is called the middle fhyreo-hyoid Ligament, ( Ligament Thyreo-Hyoid. Medium ,) though its ligamentous character is by no means well developed. It com- pletes the periphery of the larynx in the space alluded to, and, from its thin yielding nature, presents no obstacle to the motions of the os hyoides and of the thyroid cartilage upon each other. The posterior margin of this membrane, on each side, is bounded by a long, rounded, fibrous chord, the Lateral Thyreo-Hyoid Liga- ment, ( Ligamentum Thyreo-Hyoideum Later ale.) The latter is ex- tended from the cornu major of the thyroid cartilage to the tubercu- lated extremity of the os hyoides, and frequently contains, about its centre, a small oval cartilage or bone, ( Cartilago Triticea ,) not quite so large ag> a grain of wheat. Immediately under the body of the os hyoides, between its con- cave face and the middle thyreo-hyoid ligament, is a small sac or cell formed between the laminae of this ligament, and frequently ex- tending itself downwards as far as the notch of the thyroid cartilage, it is flat, about four or five lines in its transverse diameter, and pre- sents a shining surface. I have never seen a fluid in it in the na- tural state ; its secretion, however, sometimes becomes excessive, and it is then elongated downwards over the front of the thyroid and of the cricoid cartilage, as far as the isthmus of the thyroid gland. In this state it frequently forms a small fistulous opening, at its lower end, through the skin ; and which is marked by a fold of the latter across the neck. The true pathology of the disease was first pointed out by the late Dr. Physick, who cured it, in some cases, by the in-- troduction of lunar caustic, and in others by extirpation. THE LARYNX. 155 The lateral Crico-Thyroid Ligament attaches the Cornu minus or inferior horn of the thyroid cartilage to the side of the cricoid ; there is not unfrequently an articular cavity within its circle. This junc- tion is the centre of the very limited rotatory motion of the thyroid upon the cricoid cartilage. The interval in front between the thyroid and the cricoid cartilages is filled by a ligament adhering to its margins called the Middle Crico-Thyroid, to distinguish it from the ligamentous junction be- tween the inferior cornua of the thyroid, and the sides of the cricoid. The middle ligament has some small apertures in it for the passage of blood vessels and of nerves. It is the part commonly cut in the operation of laryngotomy. The Thyreo-Arytenoid Ligaments are two in number, on each side of the larynx ; one above the other, at the distance of three lines. The inferior is extended from the anterior angle of the base of the arytenoid cartilage to the inferior part of the entering angle of the thyroid, and, by converging towards its fellow, is inserted there in contact with it. Its fibrous structure is very distinct. It also bears the name of vocal chord (Ligamentum Vocale,) from its border- ing the rima glottidis. The superior thyreo-arytenoid ligament arises from the middle of the anterior edge of the arytenoid cartilage, and is also inserted into the entering angle of the thyroid ; it is more distant from its fellow than the lower one is, and goes almost parallel with it ; so that the opening between the two upper is both larger and more like an oblong, than it is between the two lower. Its fibrous structure is less distinct than that of the lower. Both the upper and the lower ligaments are covered by a reflection of the lining mem- brane of the larynx, and are small, round fibrous bands, which are rendered more or less tense by the action of the small muscles of the larynx. The superior thyreo-arytenoid ligament is attached, in its whole length, by a triangular fibro-muscular layer to the pedicle and side of the epiglottis : the posterior margin of this layer is distinctly mus- cular, and must have the effect of drawing the ligament upwards, hence this ligament is in an arched line. Lauth has described a band of radiating elastic fibres which leaves the thyroid cartilage, between the vocal chords, and expands so as to be attached to the superior margin of the Cricoid cartilage, — to / 156 ORGANS OF RESPIRATION. the crico-thyroid ligament, — to the arytenoid cartilage and its articu- lation, — and also to the lower and upper thyreo-arytenoid ligaments.* There are several pairs of muscles belonging to the larynx. 1. The Thyreo-IIyoideus, as observed in the former account of this muscle, looks like a continuation of the sterno-thyroideus. It arises, obliquely, from the side of the thyroid cartilage by the ridge, there ; and running upwards, it is inserted into a part of the base, and into nearly all the cornu of the os hyoides. When the thyroid cartilage is fixed, it draws down the os hyoides ; but when the latter is fixed, it draws up the thyroid cartilage. 2. The Crico-Thyroideus arises, tendinous and fleshy, from the anterior lateral surface of the cricoid cartilage, and passes- upwards and backwards, to be inserted into the inferior cornu of the thyroid cartilage, and into the adjacent part of its inferior edge. Use, to draw these cartilages obliquely together. 3. The Crico-Arytenoideus Posticus arises from the back of the cricoid cartilage, occupying its excavation, and is inserted into the posterior part of the base of the arytenoid cartilage. It draws the arytenoid backwards, and makes the ligaments tense., 4. The Crico-Arytenoideus Lateralis arises from the side of the cricoid cartilage, and is inserted into the side of the base of the ary- tenoid. Use, to draw the latter outwards, and open the chink of the. glottis. 5. The Thyreo-Arytenoideus arises from the posterior face of the thyroid cartilage, near its angle, and the middle crico-thyroid liga- ment, and is inserted into the anterior edge of the arytenoid cartilage. Use, to relax the ligaments of the glottis. G. The Arytenoideus Obliquus arises from the base of one ary-, tenoid cartilage, and is inserted into the tip of the other., It is a very small fasciculus, and sometimes only one muscle exists. Use, to close the chink of the glottis. * Huschke Traite de Splanch. p. 224. Paris, 1845. Also Muller Physiol, p. 1005, who considers that an extension or lamina of the same, covers the outer face of the ventricle of the Larynx. THE LARYNX. 157 7. The Arytenoideus Transversus is always a single muscle which arises posteriorly from the whole length of one arytenoid cartilage, excepting a little part of the tip, and is inserted, in a corresponding manner, into the other. It fills up the cylindrical concavity of the arytenoid cartilages. Use, to close the chink of the glottis. 8. The Thyreo-Epiglottideus consists in a few fibres, and arises from the posterior face of the thyroid cartilage near its entering angle. It is inserted into the side of the epiglottis. Use, to draw the epiglottis downwards. 9. The Aryteno-Epiglottideus consists also in a few indistinct fibres, and arises from the superior lateral parts of the arytenoid car- tilage. It is inserted into the side of the epiglottis. Use, to draw the epiglottis downwards. These last two muscles are generally so small and undefined, that they cannot be satisfactorily distinguished from the adjacent soft parts. On the posterior face of the thyroid cartilage ; of the middle thyreo- hyoid ligament ; and on each side of the epiglottis cartilage, surroun- ding its lower part with the exception of its posterior face, there is an accumulation of cellular and adipose substance. In the lower part of this substance there are several small glandular bodies, some- times insulated and sometimes collected together, which are con- sidered to detach their prolongations into the foramina of the epi- glottis cartilage, and seem to open thereby on its laryngeal surface ; they are mucous glands. The Arytenoid Gland, which is also muciparous, is situated in front of the arytenoid cartilage, in the duplicature of the mucous membrane which passes from the side of the epiglottis cartilage to the arytenoid. It is a small body of a grayish colour, resembling the letter L, and consists in distinct grains ; it is supposed to have its excretory ducts opening into the larynx. It is frequently wanting. The Interior Face of the Larynx is lined by a mucous membrane, continuous above with that of the mouth and pharynx, and below 158 ORGANS OF RESPIRATION. with that of the trachea. Where it is reflected from the base of the tongue to the epiglottis cartilage, it forms, as described, a well- marked vertical fold or frsenum in front of the middle- of the latter, and on each side of this middle fold there is another, not so distinct, but varying in different subjects. Beneath the middle fold is a strong fibro-muscular connexion with the root of the tongue.* The three folds form two pouches in front of the epiglottis, in which food is sometimes lodged. The mucous membrane also forms the dupli- cature on each side already alluded to, which passes from the lateral part of the epiglottis cartilage to the arytenoid of the same side of the body. This duplicature forms the superior boundary of the cavity of the larynx, and is very soft and extensible, permitting freely the epiglottis to be depressed and to rise again into its vertical posi- tion. The duplications of the two sides, taken together, form ari oblong oval opening into the larynx, passing very obliquely upwards and forwards to the epiglottis, and terminated behind by a notch between the cornicula laryngis. At the latter place the mucous membrane is wrinkled and loose, so as to permit, by its extensi- bility, free motion to the arytenoid cartilages. After adopting the preceding arrangement, the lining membrane of the larynx passes downwards ; it covers smoothly the posterior face of the epiglottis, adhering closely to it ; but, when it reaches the thyreo-arytenoid ligaments, it is tucked in between the upper and the lower one, so as to form, on. either side, an oblong pouch, the bottom of which is broader than its orifice between the ligaments. This pouch is the ventricle of Galen, or of Morgagni, or of the larynx ;f it projects into the fatty glandular matter on the posterior face of the thyroid cartilage, and has its base resting on the thyreo- arytenoid muscle. Its superior end reaches almost as high as the * A muscle of a triangular shape has lately been observed by the English anatomists,* situated in front of the epiglottis, passing to it from the base of the os hyoides : it is called Hyo-Epiglottideus. The observations on its ex- istence have not yet been repeated sufficiently often to determine whether it belongs to the normal structure of the body or not, and in my own dissections, for the purpose of ascertaining its existence, it has not occurred. Albinus, Soemmering, and others, speak of the occasional existence of muscular fibres there. A strong muscle is found there in the lower animals, as stated in the description of the tongue, vol. 1st. f Anat. Atlas, Fig. 420. * Am. Med. Journ. vol. v. p. 475. THE LARYNX. 159 upper margin of the thyroid cartilage, and it has some small fasci- culi of muscular fibres on its belly which seem appropriated to its use. This pouch is in fact divided into two compartments, an upper and lower ; the lower is oblong and horizontal, being between the thyreo-arytenoid ligaments ; the higher portion is a compressed spheriform sac, and communicates with the lower by a narrow' neck. The continuation of the lining membrane of the Larynx afterwards lines smoothly the cricoid cartilage, and abounds there in mucous follicles. That portion of the larynx which is formed by the thyreo-aryte- noid ligaments, and the pouches between them, is the structure essential to the formation of voice. The opening between the two lower ligaments, is the Rima Glottidis, and the space between the upper ligaments and the duplicature of the mucous membrane pass- ing from the arytenoids to the epiglottis cartilage, may be termed the Glottis. The Epiglottis Cartilage is principally useful in preventing articles of food from falling into the glottis, either in swallowing or in vo- miting. The strength of its muscles, hownver, does not seem to be sufficient to draw it down over the glottis, as many physiologists suppose ; on the contrary, I am induced to believe that the glottis is rather drawn upwards to it. If, on any occasion, it be depressed or bent down over the glottis, the position must be caused by me- chanical pressure from the bulk of the article swallowed. But the latter explanation is not sufficient to account for the swallowing of fluids, or of a very small body as a pill or a crumb of bread. Impressed with these objections, and unsatisfied with the com- mon theory, I had an opportunity, in a dissection many years ago, of witnessing a position of these parts which afforded a satisfactory explanation. The subject was a robust, muscular man, who had died suddenly. The upper orifice of the glottis was closed and pro- tected, but by an arrangement precisely the reverse of the received opinion; for the epiglottis, retaining its naturally erect position, with a slight inclination backwards, had the opening of the glottis drawn up so as to come in contact wfith its posterior face. The cricoid cartilage, as has been mentioned, slopes on its superior margin up- wards and backwards ; the front surfaces of the arytenoid cartilages, in their natural position, are nearly on a line with this slope, or a continuation of it ; the whole may, therefore, be considered in the light of an oblique plane, rising up behind the epiglottis cartilage. 160 ORGANS OF RESPIRATION. By a very slight additional elevation of this plane along with the rotatory motion of the thyroid cartilage upon its lesser cornua, the plane is caused to come in contact with the posterior face of the epiglottis, and thereby to close the upper opening of the glottis. The principal agents in this motion are the thyreo-hyoid muscles, the contraction of which, causing the larynx to ascend, the opening of the glottis is brought up behind the epiglottis, and thereby secured from the introduction of food into it. Whether the food be passed from the mouth into the stomach, as in swallowing, or from the sto- mach into the mouth, as in vomiting, is equally unimportant ; and the security is the same, whether the article be small or large, fluid or solid. Several years ago, I dissected a gentleman who had symptoms of sore throat with swelling of the neck, superadded to those of pulmonary consumption : during the existence of his sore throat, in addition to the usual difficulty of Swallowing, he was fre- quently affected in the act, with strangulation to an alarming and distressing degree. In the dissection, it was found that an abscess, of considerable extent, existed between the os hyoides and the thy- roid cartilage, and involved the thyreo-hyoid muscles. Without knowing at the time the value of this observation, I am now per- suaded that the strangulation arose from the inactivity of the thyreo- hyoid muscles. In some ulcerations of the epiglottis cartilage which I have had an opportunity of seeing; the upper circular portion which projects above the root of the tongue, has been lost ; if the accident be confined to that extent only, deglutition is not impaired, because still enough of the epiglottis is left to perform the office assigned to it, as the upper part is less essential. The cases of its reputed loss by wounds, must be considered as applying themselves to this upper portion only, because a wound low enough to remove the whole body, would cause such a destruction of the rima glottidis, as to pro- duce an embarrassment of respiration, incompatible wffth life. It is probable that the inferior constrictors of the pharynx, as well as the stylo-pharnygeal muscles, assist in this use of the thyreo- hyoidei. There is a well-marked difference in the larynx of the two sexes. In tire female, it is generally smaller by one-third than it is in the male ; the thyroid cartilage is also less prominent, in consequence of its two halves uniting at an angle more obtuse the pomum Adami is ; therefore, seldom conspicuous. The rima glottidis is also smaller in women. THE TRACHEA. 161 The nerves of the larynx come principally from the superior and and the inferior laryngeal branches of the par vagum. CHAPTER II. Of the Trachea, and the Glands bordering upon it. SECT. I. — THE TRACHEA. AND BRONCHIA.* The Trachea, or Aspera Arteria, is a cylindrical canal of four or five inches in length and about nine lines in diameter, communica- ting with the lungs for the transmission of air. It opens into the larynx above, by being attached to the inferior margin of the cricoid cartilage, and terminates in the thorax, opposite the third dorsal vertebra, by two ramifications called Bronchia. In this course it is situated over the middle line of the neck, beneath the sterno-thyroid muscles, and separated from them by the deep-seated fascia of the neck and the adipose matter beneath it. It is placed in front of the oesophagus, between the primitive carotid arteries and the internal jugular veins. When it has got into the thorax, it inclines slightly to the right side as it passes behind the curvature of the aorta. Of its two branches, the right bronchus is larger than the other ; it is also less slanting, and an inch long before it divides ; it sinks below the right pulmonary artery, to penetrate the lung about the fourth dorsal vertebra. The left bronchus being an inch longer sinks into the lung of the left side, below the corresponding pulmonary artery, and opposite the fifth dorsal vertebra. The bronchia then divide and subdivide very minutely through the lungs. Very dissimilar structures enter into the composition of the trachea; they are cartilage, ligamentous fibre, muscle and a mucous membrane. Vol. II.— 15 * Anat. Atlas, Figs. 429, 430. 132 ORGANS OF RESPIRATION. The Cartilage preserves the cylindrical shape of the trachea, and ■consists in from sixteen to twenty distinct rings, which are deficient in the posterior third of their circumference. Each ring is about tw T o lines broad, and half a line thick, and is kept apart from the one above and below it by a small interstice : sometimes, however, they run into each other. There is an almost uniform similitude between these rings ; the principal departure from which is observed in the first being rather broader in front than the others, and in the last ring, which, by its corset-like shape in front, contributes, to the beginning of each bronchus. The rings of the Bronchia, are like those of the trachea, deficient in their posterior third, and the same arrangement holds during their primitive ramifications in the lungs. But as they subdivide more and more, the cartilages do not succeed each other so closely, and are smaller segments of circles ; they are also not regularly de- ficient at the posterior third ; but in place of the latter, the bronchial ramification is furnished with cartilage, consisting in several pieces put end to end. The pieces become, afterwards, more and more scattered and smaller, till they finally disappear, and the bronchus is simply membranous. At the orifice of each branch of the bron- chia, there is a semi-lunar cartilage, forming rather more than one half of its circumference, and having its concave edge upwards : the whole arrangement resembles somewhat the pasteboard to an eared bonnet, and is evidently to keep the orifice open. The Ligamentous Structure of the trachea and of the bronchia is very evident between the proximate margins of the cartilaginous rings, and fills up the intervals between them so as to make the tube perfect. This tissue may be traced over the surfaces of the rings, forming their perichondrium, so that they may be considered as im- bedded in it. It does not exist in the same state, in the human sub- ject, in the interval behind ; where a third of the ring is defective, its place being supplied by a condensed cellular substance approach- ing to a fibrous character and intertexture ; but in the bullock it is there also. In the smaller ramifications of the bronchia, where the several little cartilaginous segments, are interposed around it ; it is probable that this tissue contributes to the whole periphery of the ramification. This ligamentous structure possesses great elasticity, which is THE TRACHEA. 163 manifested by the rapid shortening of the trachea, when its two ex- tremities are stretched apart and then suddenly let loose. And it is the continuance of this quality of elasticity, in the minute ramifica- tions of the bronchia, which proves the existence of this tissue there, even when it cannot be very distinctly seen. The Muscular Structure of the trachea exists at the cartilaginous deficiency in its posterior third, and consists in a thin muscular plane whose fibres pass transversely between the interrupted ex- tremities of its cartilaginous rings. These transverse fibres begin at the first ring, and exist all the way down : they arise from the in- ternal faces of the rings, and the intermediate elastic ligamentous tissue ; about a line beyond their extremities. Anteriorly, they are covered by the lining membrane of the trachea, and posteriorly, by the dense cellular tissue just spoken of. A similar arrangement of muscular structure occurs in the bron- chia and for some distance into the lungs. Where the cartilages become scattered and irregular, the muscular fibres are said, by J. F. Meckel, and by M. Reisseissen,* to perform the whole circuit of the bronchial ramification, and to be visible even beyond the existence of the cartilaginous pieces. Soemmering expresses a doubt of this arrangement.! It is very difficult in such minute structure to arrive at a satisfactory conclusion; careful observations, latterly made, have, however, induced me to adopt the same conviction as Reis- seissen. Longitudinal muscular fibres are said by Portal to exist between the contiguous margins of the cartilaginous rings, but the fact is far from being ascertained.^ In some subjects a very strong plane of longitudinal muscular fibres, is seen going the whole length of the trachea on its posterior face : being placed just behind the transverse muscular fibres. * De Fabrica Pulmonis. Berlin, 1822. M. Laennec says (Traite, de l’Aus- cultation, Paris, 1826, vol. ii. p. 189,) that he has sought in vain to verify these observations of Reisseissen, but that the manifest existence of circular fibres upon branches of a middling size and the phenomena of many kinds of asthma, induce him to view, as a thing well established, the temporary oc- clusion of the small bronchial ramifications, by a spasmodic contraction of their parietes. f Extimffi autem vel postica; ejus fibrae per longitudinem, a cartilagine crB coidea ad pulmones usque descendunt ac, vel in ipsis tracheae ramis haud parum conspicui sunt. — De Corp. Hum. Fabrica. ! Anat. Med. 164 ORGANS OF RESPIRATION. The use of the muscular tissue has been pointed out, by the late Dr. Physick, as follows: — “In expectoration, it diminishes the caliber of the air tubes, so that the air having to pass out with in- creased rapidity through them, its momentum will bring up the in- spissated fluid which may be in its way.” This very ingenious theory has subsequently been advanced by M. Cruveilhier, of Paris, possibly without a knowledge of his having been anticipated ; but certainly not without the claims of the eminent individual to whom we owe it, having been established by its publication.* The mucous Membrane of the trachea lines its whole interior periphery, from the larynx to the bronchia, and is continued, under the same circumstances, through the latter to their minute divisions. It adheres very closely to the contiguous structure, and is continued in the substance of the lungs, beyond the traces of any of the other tissues which compose the bronchia ; it indeed terminates in the air cells. It is very vascular, like other mucous membranes: and also, like them, the venous appears to prevail over the arterial vascularity. A successful minute injection makes it look as if it consisted of a tissue of blood vessels : thin and red, it presents an abundance of slightly elevated longitudinal folds : one of the latter, conspicuous for its greater size, exists at the commencement of the left bronchus, and is yet more developed in the still-born infant. The exterior circumference of the mucous membrane is studded with Muciparous Glands, about the size of millet seed. These glands are particularly conspicuous and abundant on the posterior part of the trachea and of the bronchia, where the deficiency of the cartilaginous rings is supplied by the musculo membranous structure only ; and more of them exist at the lower part of the trachea and upon the roots of the bronchia than elsewhere. They are placed behind the muscular layer, which their excretory ducts have to penetrate. Besides occupying these situations, they are found in the interstices between the cartilaginous rings, but here they are much smaller. The mucous membrane abounds so much in the orifices made by their excretory ducts, that it looks cribriform, wdiich ap- pearance is increased by floating it in water. About the origins of the bronchia, there is a considerable num- ber of black coloured lymphatic glands, called bronchial, which it * Wistar’s Anatomy, 3d edition, vol. ii. p. 64 Phil. 1821. THE THYHOID GLAND. 165 » is easy to distinguish from the preceding by their colour and much, greater size. There are two more glands of a different character, which, though they do not enter into the composition of the trachea, yet from their locality, are most conveniently studied at this time : they are the Thyroid and the Thymus. SECT. II. — OF THE THYROID GLAND. ^ The Thyroid Gland ( Glandula Thyroidea ) is placed on the first- and second rings of the trachea, and on the sides of the larynx. It consists in a- middle portion which is thin, of variable magni- tude in different individuals, sometimes, entirely wanting, and which, being stretched across the upper part of the trachea just below r the larynx, is called its isthmus: and of two lobes, one on each side, which, being flattened' and- ovoidal, are extended considerably up- wards on the side of the larynx, and downwards on the side of the trachea and of the oesophagus. Frequently from the superior part of the isthmus, and most commonly on its left side, a small pyramidal process runs upwards in front of the cricoid and of the thyroid car- tilage, and is attached* by ligamentous fibres to the os hyoides ; this process, however, varies much in- size and length ; I have never seen it double. According- to Morgagni and Meckel,. the existence of this process is much more common than its absence, which corresr ponds with my own observations. The thyroid gland, when ex r - tended, measures about three inches from. side to side. It is covered in front by the sterno-hyoid and thyoid- muscles*, and laterally by the omo-hyoid and-the sterno-mastoid. Embracing the trachea and the sides of the larynx, its lobes repose upon the primitive carotids, and the internal jugular veins. The thyroid gland has a capsule which is not very easily raised up, but serves to give it a polish ; it is also invested by the condensed cellular membrane of the part called fascia profunda colli. Its surface is smooth and uniform. It is of a dark brown colour. When cut into or torn, it is seen to consist of several lobules adhering tg , * Anat. Atlas. Fig* ,4,1th 15 * 166 ORGANS OF RESPIRATION. each other ; but this arrangement is not very distinct, except in an enlarged or diseased state ; and may be traced most easily by follow- ing the course of the large blood vessels, which pass in the inter- stices between the lobules. The latter contain many small vesicles, or cells filled with a transparent or yellowish and somewhat unctuous fluid : the cells are frequently in a collapsed state, which prevents them from being manifest to the naked eye. According to the ob- servations of Mr. Simon,* these vesicles are completely closed, being formed by a delicate homogeneous membrane, invested by a close capillary network. Intermixed with their contained fluid are cyto- blasts which float freely about, in it. These are found frequently as the nuclei, of cells of the diameter of 1-1400 of an inch. There are four considerable arteries which supply this body, two on each side, one coming from the external carotid and the other from the subclavian. The veins follow the course of the arteries for the most part. Bichat has made a very interesting remark on the subject of its blood vessels; that, notwithstanding their size and number, and minute ramifications in it, much less blood remains in its capillary system, than in that of the liver or kidney, as is proved by the quantity of water it tinges in maceration ; he, therefore, infers that the capillary system is less abundant. Anatomists have sought in vain for one> or more excretory ducts to this body, and some have imagined that they had found them ter- minating in the trachea, or in the larynx. Santorini considered the pyramidal' process from the isthmus as the desired duct. The em- physema with which the gland has sometimes been affected, was supposed to be a proof of its communicating with the trachea by ex- cretory tubes : but it is more probable that the air was forced into the cellular substance, uniting its lobules, and not into the structure itself of the gland. The settled opinion now seems to be, that whatever fluid it secre- tes is conveyed away by the lymphatic vessels. Meckel has sugges- ted, that as this gland is more voluminous proportionately in early infancy, particularly its pyramidal process, possibly the duct may be obliterated when the gland begins to be restrained in its growth ; but, if this were the case, the duct ought to have been found during the period indicated. The probability is, that it is a diverticulum pf blood from the salivary glands during the intermittence of their * Phil. Trans. 1844. THE THYMUS GLAND. 167 action ; and from the marked sympathy between it and the brain in goitre, it may exercise a corresponding function on this organ during its intervals of repose. Duverney* has described a small azygous muscle on the middle line of the body, coming from the under margin of the base of the os hyoides, and running over the middle of the thyroid cartilage, to be insertedlnto the upper margin of the isthmus of the thyroid gland. Soemmering calls it Levator Glandulae Thyroideae, and speaks of it as being found more frequently on the left side, and about half of the breadth of the thyreo-hyoideus. After many special examinations for it I have found it in but few instances; I, therefore, consider it rare ; though without a close attention to structure, the pyramidal process of the isthmus of the gland may, from the similitude of colour and position, be very readily mistaken for it, which I have reason to believe has been frequently the case.f Some few fibres are often found going to the isthmus of the gland from the crico-thyroid, and the thyreo-hyoid muscles, or from the thyroid cartilage. SECT. III. — OF THE THYMUS GLAND J This body ( Glandules. Thymus ) is placed between the trachea and the upper extremity of the sternum. It is irregularly triangular, its broadest part being above, and the narrower below. In the adult, it is in a collapsed and shrivelled state, and scarcely presents a ves- tige of what it once was ; it is, therefore, only in the infant that it can be satisfactorily studied. At birth, it is much larger, not relatively, but actually, than it is in the adult, and extends from the body of the heart up to the thy- roid gland. It is of a very soft consistence and of a pink colour. It is surrounded by a capsule of cellular substance, which, when re- moved, permits the gland to be resolved into two lobes, one on either side, which adhere to each other. These lobes may be sepa- * Essai D’Anatomie en tableux imprimes, pi. IV. Paris, 1745. f The unassisted eye, in a strong- light, is generally sufficient to determine the structure ; but in case of doubt, by boiling the gland, if there be muscular fibres along this process, their longitudinal and parallel direction will become evident; they also may then he torn asunder, so as to be made still more dis- tinct; whereas, the vesicular structure of the gland is not susceptible of divi- sion into fibres. % Anat. Atlas, Fig. 426. 168 ORGANS OF RESPIRATION. rated with facility into lobules, which contain a whitish cream-like fluid. A good Essay on the structure of this gland, has been published by the distinguished British surgeon and anatomist, the late Sir Astley Cooper,* illustrated by excellent plates. From this it ap- pears that the lobules of tbe gland are formed of vesicles of various sizes, discharging into pouches at the base of the lobules, and they again discharge into a duct or common reservoir, which runs from one end of the gland to the other, the consistence of which duct is extreme- ly feeble. This duct, the pouches, and the vesicles, may be filled with an injection, by means of a pipe introduced into the substance of the gland. A large lymphatic trunk passes from the gland, on each side, into the transverse vein near its junction with vena innominata of the right side or at the junction itself. The observations of Sir Astley Cooper, have been confirmed in their main features, by those within two or three- years past of Dr, Oesterlin of Jena, and of Mr. Simon of London, who also assert that the c.ream-like fluid of the vesicles is mixed with a multitude of cor- puscles, having the structure and relations of nuclei. Many of the corpuscles are circular, but others are flat and disk-like. Their ave- rage diameter is about the 1-3839 of an inch, and they are charac- teristically dotted with from two to five very small dark spots, which are either collected or dispersed. f Sir Astley thinks, or, rather, asks, whether this gland does not prepare a fluid for fetal nourishment, in the absence of proper chyli- fication, during fetal life ? inasmuch as all the elements of the blood are upon chemical analysis, found in the fluid contained in its cavi- ties. It is visible in the third month of gestation, and continues to grow till the end of the second year of extra-uterine life. It then collapses, and its structure is effaced about the twelfth year ; its remains are scarcely distinguishable subsequently from the surrounding cellular substance. It is stated by KrauseJ that in almost all individuals of from twenty to thirty years- of age, in whom he has examined the con- dition of this gland, it was still existing, and in some instances, larger than in children ; and that in persons of from thirty to fifty years he had found it of considerable size. It has latterly happened to me to * London, 1832. j- Br. and For. Med. Review. April, 184G. j: Muller’s Physiology, p. 622. THE LUNGS. 169 see it in two persons of from twenty to thirty years old, forming an oblono- oval body, two inches or more long by twelve or fifteen lines wide, and preserving its characteristic structure and division into lobes and lobules. No excretory duct has been found for it, unless we may consider as such the lymphatic trunk alluded to by Sir Astley Cooper. Though it clearly belongs to foetal and infantile existence, its use is problematical. The probability is, that it is a diverticulum of blood from the lungs during their state of quiescence in foetal life, and until their structure becomes confirmed and propor- tionately evolved. CHAPTER III. Of the Lungs.* The Lungs ( Pulmones ) are the essential seat of the process of respiration, and occupy the greater part of the cavity of the thorax, as formed by the ribs and the intercostal muscles on the sides ; by the sternum and its cartilages in front, by the dorsal vertebra: behind, and by the diaphragm below. They are two bodies, placed one on either side of the thorax, and separated from each other by the heart and its great vessels. As the heart is the only organ of much volume which is also included in the cavity of the thorax, the size of the lungs is in a direct relation with the capacity of the latter ; and may, therefore, be known by external indications in the living body. It is probable that there is no void, or only a very small one, betw-een the sides of the lungs and the sides of the thorax. Each lung forms an irregular cone, the apex of which is above, and the base below ; the latter, from resting upon the diaphragm, is consequently, oblique from before backwards and dowmwards, and is also concave. The surface which reposes against the periphery of the side of the thorax, is, uniformly, rounded ; but that which looks towards its fellow, is concave, from being pressed in by the heart. The vertical diameter of the lung behind, when it is fully distended, goes from the head of the first to that of the last rib, and is, from the oblique direction of the diaphragm, consequently, much * Anat. Atlas, Fig. 427. 170 ORGANS OF RESPIRATION. more considerable than the vertical diameter in front, which extends only from the first rib to the inferior end of the second bone of the sternum, or, in other words, to a level with the tendinous centre of the diaphragm. The lungs of the adult are of a light pink colour, with specks or patches of black ; in early life there is much less of the latter, and in advanced life it becomes more abundant. The left lung is divided into two lobes by a deep fissure, which begins behind, on a level with the fourth dorsal vertebra, and runs obliquely downwards and forwards to the anterior margin of its base. A deep fissure in a nearly similar situation is observed on the right lung ; but from it another fissure branches out forwards, by which the right lung is divided into three lobes. The internal face of the left lung is also rather more concave than that of the right, from the side of the heart projecting into it. The right lung is more volumi- nous than the left, which corresponds with the greater size of the bronchus on this side, but its vertical diameter is not so great, owing to the pressure of the liver from below ; though this diameter is in- creased by the descent of the liver when we are upright. Near the middle of the internal face of each lung are to be seen the points of connexion with the bronchus, and with the pulmonary vessels. Before these the anterior margin is thin, and more or less winding where the lung is introduced between the heart and the front parietes of the thorax. When the lungs are fully inflated, only a very small portion of the front of the pericardium can be seen be^ tween them. The posterior margin is thick, and rounded where it rests against the vertebral column. The whole rounded circumference of the lung as well as its base, though they are in contact with the parietes of the thorax, do not adhere at any point to them. The connexion of the lung, constitu- ting its Root, as it is called, and by which it is maintained in its situation, is entirely on the side of its concave face, where the pul- monary vessels and bronchus enter, and though other attachments are frequently found springing from different points of the thorax, they are purely the results of disease. Of the Texture of the Lungs. Each lobe of the lungs is divided into a great many distinct lo- bules, which adhere together by intermediate cellular tissue. The THE LUNGS. 171 marks of these divisions are apparent on the surface by lines run- ning in different directions, but they are made still more distinct by tearing them asunder. The Lobules are sub-divided into very fine air vesicles or cells, which maybe considered as the dilated termina- tions of the ultimate branches of the bronchia, with the same struc- ture of an elastic and of a mucous membrane. The opinion is gener- ally held, that the cells do not communicate laterally with one another as the cells of the bones, but only with the ramifications of the bron- chia, to which they respectively belong. Numerous observations however, have induced me to abandon this idea, and to conclude that the cells of the lobules individually communicate, but not those of different lobules. I have succeeded in proving this by distending the air cells with tallow, and, after the lung was dried, removing the tallow with spirits of turpentine. This process shows the cells of their natural size, and communicating freely. A very small por- tion of a lung of either the human subject or the calf kept inflated and dried shows the same unequivocally.* * * § The most prevalent opinion, however, of the day is that derived from Willis originally, that the air vesicles have the same relation to the bronchioles, that the berries have to the stem in a bunch of grapes. This idea has been reiterated by Reisseissen,f and his plates fallaciously taken as the standard of structure, in the anato- mical works generally. It has also been reasserted still more lately, by Huschke under the declaration of the opposite being the repro- duction of an ancient error, f On the contrary, my opinion, sus- tained by numerous anatomical preparations, may be traced as far back as Helvetius and Duverney, and has as its advocates Haller, Soemmer- ing, J. F. Meckel, and Cruveilhier. The doctrine is moreover de- cidedly advocated with some modified views, in regard to the shape of the cells, by J. M. Bougery, an anatomist now well known for his splendid anatomical plates. The leading peculiarity of his views, is that the cells, though they communicate freely, are yet canalicular, § that is, they have the measurement of length exhibiting great excess over every other, in which I do not agree with him. In tracing the terminations of the bronchia, in the substance of the lungs, the parietes of these canals are observed to become very thin, * Anat. Atlas. Fig. 427. from preparation in Anat. Museum. f De Pulmon. Struct. 1803. f: Traite de Splanch. p. 249. Paris, 1845. § Gazette Med. de Paris. July, 1842. 172 ORGANS OF RESPIRATION. and especially after the cartilaginous structure has ceased. The ra- mifications or bronchioles seem then to be composed almost entire!) of a filamentous coat, lined with a delicate mucous membrane. The filamentous coat, is no doubt an extension of the membra- nous portion existing so conspicuously on the back of the bronchia, and it retains the extensibility and contractility of the same. Its filaments are principally in a circular direction and resemble so strongly muscular fibres, that they alone seem to exist. It is, how- ever more probable, that exterior to these, we have a fine elastic ligamentous layer, or it may be blended with them, it being difficult to distinguish where there is such a sameness of colour, the one tissue from the other. Some anatomists, have indeed, considered it all as of an elastic ligamentous character, in which case, the circu- larity of the fibres, may be compared to the same condition in the internal layer of the corpus cavernosum penis. The lining mucous membrane of the bronchia is smooth, polished, and so thin that it is a mere film, about the thickness and transpa- rency of the peritoneum, where it covers a small intestine. Longi- tudinal folds may be traced in the length of this mucous membrane for some distance down the bronchia, indeed as far as the cartilagi- nous segments of circles appear, and even into the finer branches. With the aid of a lens, mucous follicles are very perceptible in innumerable cpiantities all over it. It may also be remarked, that the bronchia do not end by a regular succession of proportionately finer and finer branches ; but that a bronchial trunk, of some lines in diameter, sends off in different directions to the contiguous lobules, branches about the size of a bristle, which are followed with much difficulty, owing to their collapsing : the probability is, however, that each one of these branches belongs to a lobule and discharges into its cells, in a manner,' resembling a blow-pipe fixed to the side of a small piece of sponge. In my preparations, these terminating tubes of the bronchia, the size of bristles, are seen very distinctly ; but there is no appearance of the penicillous arrangement, which would be apparent if each cell had its owm specific branch of the bronchus running to it. The internal surface of the lung owing to this multiplication of it by cells, may be considered as a vast area obtained in a very small space, and containing a close intertexture of the most minute capil- laries, for the purpose of exposing the blood to the process of respi- ration. THE LUNGS. 173 There is no absolutely uniform size for the air vesicles, but their diameter may be stated as from near the two hundredth part to the fiftieth of an inch. Weber says from the T ^9 to jis- The capillary blood vessels have an extremely attenuated distribution over them; leaving scarcely any thing like regular interstice, these capillaries are in their own diameter, about the twentieth part of the diameter of the smaller air vesicles. The readiness of pulmonary haemorrhage, is a sufficient proof of the facility with which blood passes from the blood vessels into the air vesicles and bronchial tubes. An opposite line of commu- nication from the air vesicles into the pulmonary blood vessels has latterly attracted my attention, and been the subject of several experiments, which prove conclusively the certainty of the fact. These experiments show that water or air may be injected into the air passages of the lungs, and returned by the pulmonary veins, and the pulmonary artery, but with especial freedom through the pulmo- nary veins.* Whether this is by an absolutely direct communication, or by the intervention of the lymphatic system I cannot at present determine, but the existing state of my experience is in favour of the first. It may, however be stated, that it is a matter of common ex- perience with anatomists, to inflate the pulmonary lymphatics from the air vesicles ; also, to inject the pulmonary lymphatics from the bronchial arteries, and therefore, the communication of the air vesi- cles with the blood vessels^may be by this series of anastomoses ; that is going from the air vesicles to the lymphatics, and from them into blood vessels, which all communicate freely with one another. Besides the ramifications of the bronchia, the substance of the lungs is composed of numerous blood vessels and lymphatics, and is well supplied with nerves. The blood vessels are of two kinds, the pulmonary and the bron- chial. The pulmonary artery, coming from the right ventricle of the heart, divides under the arch of the aorta into two large branches: one for the right lung, and the other for the left. The right branch is larger than the left. Each of these branches having reached the upper part of the root of its respective lung, begins there to distri- bute itself in large trunks, which divide and subdivide throughout the substance of the lung. The terminating branches finally become capillary, and ramify in the parietes of the air cells, where the blood * For the details of Experiments, see Am. Journ. Med. Sc. p. 332. April, 1843. 1 74 0RGAXS OF RESPIRATION. which they carry, from being dark-coloured and venous, is so altered as to have the arterial qualities restored to it, and to become of a bright red. From the ultimate branches of the pulmonary artery, arise the first branches of the pulmonary veins. These are succes- sively accumulated into two large trunks on each side, which, issuing at the lower part of the root of the lung, go to open into the left auricle of the heart. It has been remarked by Mr. Boyer, that the two pulmonary veins, are less capacious than the pulmonary artery of the same side, in which they manifest a peculiarity of blood ves- sels, differing from what exists in other parts of the body. The pulmonary artery and veins are distributed in company with the bronchus. From the observations of Professor Mayer, it appears that valves exist in the pulmonary veins, contrary to the general opinion of anatomists. They are found where smaller trunks join the larger ones, at an acute angle ; but there are none where they join at a right angle.* The second order of blood vessels, being the bronchial, also con- sists in arteries and in veins, and are for the nourishment of the lungs. They, too, attend the branches of the bronchia. The bron- chial arteries pervade the substance of the lung by innumerable fine branches, and anastomose with the pulmonary arteries. The bron- chial veins also anastomose with the pulmonary veins, but, finally, come out in small trunks from the root of the lung; the right one empties into the vena azygos, and the left into the trunk of the su- perior intercostal veins of the left side about the third dorsal vertebra. The Lymphatics of the lungs are numerous ; after traversing the black bron- chial glands, those of the left side empty into the tho- extremity. The nerves come princi- pally from the par vagum. Some of them are distributed with the bronchus, and may be traced easily far along its racic duct, and those of the right into the large lymphatic trunk coming from the upper Fig. 33. Arrangement of the Capillaries of the air- cells of the Human Lung. * Am. Med. Jour. vol. iii. p- 186. THS LUNGS. 175 branches, forming beautiful anastomoses around them : their texture there resembles much that of the sympathetic: they are thought to be, finally, spent upon the mucous membrane : others seem to be more specifically appropriated to the vessels. It will now be understood that the root of each lung is formed by a pulmonary artery, two pulmonary veins, and a bronchus, covered by the pleura, where the latter extends from the lung to the pericar- dium. The relative situation is such, that the pulmonary artery is above, the bronchus in the centre and behind, and the pulmonary veins below. The texture of the lung is so light and spongy after an animal has once breathed, that its weight is very inconsiderable when compared with its volume. Its cells are left much distended, even when the animal is dead ; and, notwithstanding from its unusual elasticity, it expels a great quantity of air when the thorax is opened, and is- thereby reduced to a third of its size during life ; yet it retains enough air to make it float in water, or even in spirits of wine. The quantity of air which the lungs contain differs very considerably in different individuals, depending entirely upon the capaciousness of the thorax. Its medium amount is computed at one hundred and forty-five cubic inches, thirty cubic inches of which are changed at every act of respiration. Of the Pleura* Each lung has a perfect covering of a serous membrane, called Pleura, to which it is indebted for its shining surface. This mem- brane is also reflected from the internal surface of the lung to the adjacent side of the pericardium, and is then spread over the inte- rior periphery of that half of the thorax to which it belongs, by lining the ribs and intercostal muscles, and covering the convex face of the diaphragm. There are, therefore, two pleurae, each of ■which is confined to its appropriate half' of the thorax, so as to line its cavity and to cover its lung. The pleura, as other serous membranes, is a thin sac. Its circum- ference is entire, like that of an inflated bladder ; there is, therefore, no point or line at wdiich one may exclusively begin an account of * Anat. Atlas, Fig. 436. 176 ORGANS OF RESPIRATION. its course and attachments. To commence, however, at the ster- num ; the pleura goes thence outwardly to line the lateral parietes of the thorax, as formed by the cartilages of the ribs, the ribs them- selves, and the intercostal muscles. In this way it may be traced around to the dorsal vertebrae, and over the convex surface of the diaphragm. In proceeding along the first rib, which is very oblique, it forms a sort of bulging bag, which projects towards the trachea, lines the lower part of the scalenus anticus muscle, and receives the upper extremity of the lung. The pleura, having reached the dorsal vertebrae from the ribs, passes from their sides forwards to the pos- terior part of the pericardium, a very small portion of which it covers. It then goes upon the posterior face of the pulmonary ves- sels and of the bronchus to the lung, and applies itself closely to the latter. It then covers the part of the lung posterior to its root, and continues to advance along the rounded surface of the lung to its anterior margin : it then passes over the internal surface of the lung, which is anterior to its root. It afterwards covers the front of the pulmonary vessels and of the bronchus, and gets in a very short space to the pericardium. It then passes forwards on the side of the latter, and having got near its middle line, goes from it to the sternum, and reaches the line from which the description of its course commenced. There is no important difference between the two pleurae, either in their mode of reflection or in the organs, to which they are at- tached, so that the description of one will apply to the other. The portion of each pleura covering the lung is called Pleura Pulmonalis, and that portion which lines the thorax is the Pleura Costalis ; that covering the Diaphragm is the Pleura Diaphragmalis. A duplica- ture of the pleura commences at the inferior margin of the pulmo- nary veins, and, descending as far as the diaphragm, attaches the inferior portion of the posterior margin of each lung, to the side of the pericardium in front of the vertebra. This duplicature is the Ligamentum Pulmonis. It is longer on the left lung than on the right, by reason of the greater vertical diameter of the former. From what has been said it will now be readily understood, that the whole* cavity of the thorax is divided vertically into two halves, by that portion of the two pleura which advances from the spine towards the sternum. This septum is called the Mediastinum, and the heart, enveloped by the pericardium, is placed in its centre, and separates the two pleura widely apart. It has been found THE LUNGS. 177 useful by anatomists, for descriptive purposes, to subdivide the me- diastinum into three portions or regions. One passing from the front of the pericardium to the posterior face of the middle line of the sternum, is the Anterior Mediastinum ; another, passing from the posterior face of the pericardium to the dorsal vertebrae, is the Posterior Mediastinum ; and a third, which is within the circuit of the first ribs, is the Superior Mediastinum. This division, though evidently arbitrary, is indispensable to a correct account of the relative situation of very important organs placed between the two pleurae. 1. The Anterior Mediastinum is less important than the other two ; the portions of the two pleurae of which it consists are almost in contact, and contain between them some loose cellular substance by which they adhere together, and by cutting through wdiich, after a longitudinal section of the sternum, they are easily separated from one another. The upper part of this septum contains the remains of the thymus gland; its lower part leaves the middle line of the sternum, and inclines to the left side; and when the sternum, is- narrow below, it is attached to the anterior ends of the cartilages of the lower true ribs of that side. 2. The Posterior Mediastinum, where it leaves the vertebra to reach the pericardium, passes off from a line nearer, the heads of the ribs on the left side, than on the right. The descending portion of the thoracic aorta is contained within this septum, on the left side of the dorsal vertebra. The oesophagus is in its middle in front of the vertebrae above, but, in descending it crosses- in front of the aorta, and inclines to the left side of the dorsal vertebra to reach the fora- men cesophageum of the diaphragm. The vena azygos occupies the right side of this mediastinum, and, after ascending, forms an arch over the root of the right lung, and terminates by joining the descending cava. The thoracic duct, after entering the thorax be- tween the crura of the diaphragm, ascends in front of the dorsal ver- tebra between the aorta and the vena azygos, and behind the oeso- phagus, till it reaches the third dorsal vertebra ; it then inclines to the left side, and mounting into the root of the neck near the ver- tebra, it, finally, makes an arch, which, by advancing forwards, ter- minates in the angle formed by-the junction of the left internal jug.u- 16* ITS ORGANS OF RESPIRATION. lar and left subclavian vein. The par vagum nerve, of both sides, is also in the posterior mediastinum. 3. The Superior Mediastinum is bounded in front by the upper part of the sternum, behind by the upper dorsal vertebrae, and later- ally by the first ribs. The cavity is conoidal, with the base upward, but is too peculiar to admit of a rigid comparison with any thing else. The pleurae are reflected downwards from the internal edge of the first ribs, not abruptly, but in a rounded bulging manner, re- ceiving there, as mentioned, the tip or apex of the lungs, and lining the inferior surface of the scalenus anticus muscle. In order to un- derstand well the position of the pleurae, it must be borne in mind that the upper rib is placed very obliquely downwards and forwards, at an angle of about forty-five degrees with the spine ; consequently, the pleura, on being reflected from its whole internal edge, is much higher at the head of the rib than it is at the anterior extremity of the same. This cavity is continuous, of course, with that of the anterior mediastinum in front, and also with that of the posterior mediastinum behind^ The remains of the thymus gland are where this cavity joins the anterior mediastinum : a part of the gland is, indeed, in each of these cavities just below the transverse vein. In contact with the right pleura is the descending Vena Cava. The common trunk of the Left Subclavian, and Internal Jugular, called the Transverse Vein, or Vena Innominata, after crossing in an oblique descent behind the upper portion of the sternum, joins the descending cava an inch above the place where the latter penetrates into the pericardium. Behind the transverse vein are the top of the arch of the aorta, the arteria innominata, the left carotid, and the left subclavian. The trachea, with the oesophagus behind it, descends along the middle line in front of the spinal column. The arteria innominata crosses the front of the trachea from left to right in ascending; it is in contact with the transverse vein, and more superficial than either of the other arteries. The phrenic nerve, passing at the internal edge of the scalenus anticus, between the subclavian artery and vein, descends vertically in contact with the pleura. The par vagum passes along the side of the trachea, and afterwards behind the corresponding bronchus, having got into the superior mediastinum between the subclavian vein and artery: its inferior laryngeal branch encircles the THE LUNGS. 179 subclavian artery on the right side, and the arch of the aorta on the left. The internal surface of the pleura is smooth and polished, and is moistened and kept lubricated by an unctuous serum, the natural quantity of which is merely sufficient to allow the parts to slide freely upon each other. In dropsy of the chest, it is augmented frequently to such an amount as to cause the collapse of the lung by pressing upon it. In the cellular tissue, between the pleura and pericardium, as well as on the diaphragm, adipose matter, in considerable abundance, is found in corpulent persons advanced in age. The blood vessels of the pleura costalis are derived from those which supply the parietes of the thorax, as the intercostals and phrenics. They ramify in the subjacent cellular substance, and end by exhalant orifices on the internal face of the pleura, from which a minute injection is poured out very copiously. BOOK VIII OF THE CIRCULATORY SYSTEM. PART I. HISTOLOGY OF THE CIRCDLATORY SYSTEM. CHAPTER I. General Considerations. The Circulatory or the Vascular System, consists in a congeries of tubes, or cylindrical canals, which convey the blood to and from every part of an animal body, and therefore, enter into the texture or composition of almost every portion of it. In all animals there seems to be a necessity for the alternate reception and discharge of alimentary materials; in the higher orders, this is effected through the agency of the vascular system ; but in the most simple animals this system does not exist, and their whole fabric being soft and permeable, nutritious matter is introduced by a direct absorption, or a species of capillary attraction, after the manner of a sponge, or any other porous body, and is discharged by a process equally simple.* It is probable that there are some parts of the human body whose mode of nutrition is analogous to the latter; as, for ex- ample, the articular cartilages, the hair, nails, and so on; for many observations tend to prove that all these organs have an interstitial circulation. * Hunter on the Blood. Bedard, Anat. Gen. 1S2 CIRCULATORY SYSTEM. In many animals, the blood is propelled from a central point, called the heart, to all parts of the body, and then returns again to the heart. The first movement is executed through canals called arteries, and the second through veins. It is the most simple scheme by which a circulation can be carried on through a sangui- ferous system, and requires a heart with only two cavities; one for propelling blood into the arteries, or departing tubes, and another as a reservoir for receiving the blood of the returning tubes, or the veins. The two cavities must be near each other, and have a valvular opening between them, which will permit the blood to pass from the venous into the arterial reservoir; but not from the arterial into the venous. A circulation of this simple cast is found in fishes, and in animals generally whose respiration is effected on the surface of the body; but in man, and in other warm-blooded animals, where respiration is carried on interiorly by means of the lungs, their circulatory apparatus is double; one part being for the lungs, and the other part for the body generally. In man, the heart consists of four cavities; two auricles, or re- servoirs of blood from the veins, and two ventricles, into which the venous blood is transmitted, and which, in (heir functions, may be compared to the forcing-pump of a fire-engine. The circulation is effected in the following manner: The blood contained in the right auricle of the heart flows into the right ventricle, and from the latter it is forced through the pulmonary artery into the lungs. It returns from the lungs through the four pulmonary veins, and is received into the left auricle of the heart; from the latter it flows into the left ventricle, and is propelled from it into the aorta. The aorta then distributes it through the whole body by an infinitude of small branches; from the latter it is collected, by corresponding veins, into two trunks, the Ascending and the Descending Vena Cava. The ascending vena cava brings the blood from the lower extremities and from the abdomen ; the descending vena cava brings the blood from the head and neck, the upper extremities, and the parietes of the thorax. These two trunks finally discharge the blood into the cavity from which it started, to wit, the right auricle. The same round is then renewed, and continues to be repeated during the whole course of life. It is customary for anatomists to call the route of blood from the right ventricle, through the lungs, to the left auricle inclusively the lesser or the pulmonary circulation; and GENERAL CONSIDERATIONS. 183 that which begins at the left ventricle, goes through the whole body, and ends in the right auricle, the greater circulation. The blood contained in the veins of the greater circulation, in the right auricle and ventricle, and in the pulmonary artery, is of a dark brown or reddish colour; while that contained in the pul- monary veins, in the left auricle and ventricle, and in the aorta and its ramifications, is from being vivified by respiration, of a carmine or vermillion complexion. The celebrated Bichat has, upon this difference of colour, founded his division of the whole circulating system into two parts; one containing black blood, “ System e vas- culaire a sang noire ;” the other red blood, “ Systeme vasculaire a sang rouge.” This division having general physiology for its object, affords a well marked distinction, suited to such discussions. The lymphatics also are a part of the circulatory system, but as they do not commonly convey red blood, the consideration of them will be introduced subsequently. “ They take a very active part in the animal economy, whether natural or diseased, and seem, in many actions, to be the antagonists of the arteries, while the veins are much more passive being principally employed in returning the blood to the heart.”* The largest vascular trunks are situated near the centre of the body and limbs, on the side upon which flexion is accomplished, while those near the surface are generally small. Most commonly there are one artery, one or two veins, and several lymphatics, all together. The arterial system in its external configuration may be com- pared to a tree, the trunk of which is attached to the heart, and which by a continued succession of divisions and subdivisions reaches to every part of the body. There are no means of estima- ting rigidly the collective area of the branches in proportion to that of the trunk, but a little observation on the size of the primitive branches will satisfy one of a great excess on the part of the latter; and as the rule is maintained throughout, there must finally be an immense disproportion. We have then reason to believe, that if all the branches were assembled into a single cavity this cavity would be somewhat like a cone, the apex of which would be next to the heart. The same rule holds in regard to the venous system, it being observed, however, that the latter has two trunks connected with the * Hunter, loc. cit. 184 CIRCULATORY SYSTEM. heart instead of one. The general rule is, therefore, established throughout the vascular system, that the collective area of the branches is always greater than that of the trunk from which they proceed.* By the same rule the circulation in the branch must be * I am indebted to a scientific friend, Mr. Erskine Hazard, for the follow- ing computation, by actual measurement, of the arteries, from which it appears that in many of them, at least, the area of the trunks is greater than that of the branches near them. The Left Carotid at the Aorta is - - - - .42 Its diameter at the branching is - .43 Increase of diameter .01 Its square at the Aorta is 1764 Each Carotid branch measures .28 and the sum of their squares is 1568 The difference of the areas of the Carotid and its branches is 12^ per cent, in favour of the Carotid. Diameter of Aorta near the Iliacs - .64 Its square ------ 4096 Diameter of Left Iliac ----- .40 Its square ----- 1600 Diameter of Right Iliac .... .37 Its square ----- 1369 Sum of their squares - 2969 Aorta largest by nearly 38 per cent., or ... 1127 Square of Right Common Iliac, as above, ... 1369 Ditto External Iliac ----- 900 Ditto Internal do - ... - 729 1629 Branches largest by nearly 19 per cent., or - - - 260 Square of Left Iliac as above, - 1600 Ditto Internal Iliac - - - - ... 9G1 Ditto External do ----- - 900 1861 Branches largest by above 16 per cent., or - - - 261 GENERAL CONSIDERATIONS. 185 more languid than in the parent trunks, as this circulation is retarded both by additional friction and by having to fill up a larger canal. * Great Sinus of Valsalva - - - - 13456 Innominata ------ 2601 Carotid ------- 1444 Subclavian ------ 1024 Aorta beyond ------- 3600 8669 Sinus greater than all, by * - - - - 4787 or 55 per cent. Comparison of the areas of the Iliac Arteries, with that of the Aorta, half an inch above them, in decimals of an inch. Left Iliac. Aorta. Right Iliac. Greatest diameters .354 .556 .390 Least do .290 .410 .290 Sum of diameters .644 .966 .680 Mean diameters .322 .483 .340. Their squares 103684 233289 115600 103684 Sum of the squares of the Iliacs - 219284 Square of the Aorta - - - 233289 Aorta larger than the Iliacs - - - - 14005 or nearly 6 per cent. As the areas of circles are to each other as the squares of their diameters, it follows that the aorta will contain, in a given length, nearly 6’’ ] 4 ff per cent., more than the two iliacs ; and, consequently, the blood must flow that much faster through the iliacs than through the aorta, as the same blood has to be disposed of in both, in the same time. By this means the power of the heart is continued much farther through the system, as each artery is large enough to supply its branches with but little friction. The interior surfaces of the above iliacs are, together, 2.0806 inches, while that of the aorta is but 1.518 inches, or only three-fourths of the rubbing surface! Independently of this circum- stance, it is found that there is a greater difference in the quantities of fluids passing through apertures of different sizes than there is in the areas of the respective apertures. This is accounted for by their being less friction between the particles of fluids, than there is between these particles and a solid ; and, in the larger apertures, a smaller proportion of the particles comes in contact with the solid. * It is computed that the blood moves 5233 times slower in the capillaries than in the aorta. Vol. II.— 17 186 CIRCULATORY SYSTEM. The course of rivers exemplifies this continually ; while confined to narrow channels, they rush tumultuously through them, but when they begin to expand themselves into capacious basins, or to be di- vided into a multitude of smaller channels, the current becomes slower, and in some cases imperceptible, though the fact is clear, that an equal volume of water is every where descending in the same period of time. The moisture conferred upon all parts by the circulation of the blood, bears a sufficient analogy to the effects of irrigation upon ground. The w'ater may be conducted to the latter by a canal, and is finally divided into an infinitude of streamlets, which ramify every where, and from the porosity of their beds percolate laterally, so that the whole field, even to its most minute atom, is kept moist- ened. The streamlets, afterwards, successively assemble again into a single canal, w'hich bears off their superabundant waiter. From the nature of the particles of blood, many of them are confined to their proper channels, and can never pass off by percolation into the tissue, through which the blood vessels ramify. This may be proved by the fact of the red globules of blood having a diameter of from the three-thousandth to the five-thousandth part of an inch, a size inconsiderable as it is, yet too large to permit their flowing through elementary fibres or atoms; whereas serum, or the w T ater of the blood, may, from the extreme fineness of the particles, be ab- sorbed by any tissue whatever ; a circumstance entirely unquestion- able, both from daily observation, as, for example, in soaking a piece of dried meat or a bone; and from the reflection, that the air itself will hold a certain quantity of water in solution. A question then arises whether the moisture of parts not supplied with red globules of blood, comes in the living body exclusively from infiltration or from a peculiar set of vessels called exhalants, often talked of, but as yet never seen? That the lateral porosities of blood vessels are large enough to allow watery fluids to exude, is readily proved by injecting water into the blood vessels of a limb, or, of any other part, when the latter invariably becomes cede- matous. It is in this way even possible to inundate a living animal, as I have seen accomplished by M. Magendie, in Paris. This moisture requires a change, and by continued additions w'ould be- come superabundant : as it has been thrown out of the common cur- rent of the circulation and could not be removed in any other way, the lymphatic system has, therefore, been added for the purpose. GENERAL CONSIDERATIONS. 187 In the lower orders of animals, who are destitute of the blood ves- sels, the interstitial change of moisture goes on without lymphatics. No part of the human body is exempt from moisture, but it is furnished by smaller streams, and is also less abundant in* some tex- tures than in others ; for example, though blood vessels susceptible of conveying red blood do ramify through tendons and ligaments, yet they are not numerous, apparently ; not more so, indeed, than what is sufficient to keep up by a deposite of serum, the flexibility of those parts. The vascularity of a part during life may be ascer- tained by a simple process after death, the most vascular always lose proportionately of their bulk by drying ; for example, a muscle shrinks more than a tendon, a gland more than a muscle, Besides the operation of the lymphatics, much of the super-abum dant moisture is carried oft by insensible perspiration and evapora- tion from the surface of the body : the latter process, however, is much restrained by the peculiar character of the cuticle, without which it would become excessive, probably so much so as to exceed any supply of fluid through the stomach. The red globules of the blood, besides their less obvious uses, unquestionably serve to inspissate the serous or watery part, by an intimate mixture with it, and thereby put a certain restraint upon its extravasation. They also, from their size, serve to keep open the channels through which the blood circulates. So much associated is the existence of red globules with regular blood vessels , that there are but few examples of animals having the former, without also having the latter ; whereas, in animals whose circulating fluid has not red globules, but is a mere serum, the entire destitution of regular blood vessels is very common, and their circulation, if the name be deserved, consists simply in the transmission of moisture from one pore to another, as occurs in a rag or in a sponge, by mere capillary attraction. Such animals form a numerous class in the chain of or- ganized beings, and have a gelatinous consistence. A remarkable feature in the vascular system, both arteries and veins, is the disposition of trunks to run into one another ; or to form an anastomosis, whereby, if the blood should be cut off by one route, it may still be supplied through another. These communications are frequent in the head, in the neck, in the thorax, in the abdomen, 188 CIRCULATORY SYSTEM. and in the extremities; they exist, indeed, wherever the blood ves- sels do, and become more numerous as the blood vessels are smaller, or more removed from the centre of the circulation. It is unneces- sary here to specify instances, as the more remarkable ones will be mentioned at a proper time. But some estimate may be made of their importance, and of the facility of communication established by them, when it is remembered that cases have occurred of ob- structed aorta, without the circulation ceasing in the parts of the body beyond it : the same has occurred to the venae cavae, and to the thoracic duct also.* The extreme vascular ramifications are called Capillaries, ( Vasa\ Capillaria,) and they form the connexion between the arteries and veins; or, by being intermediate to the two, they are the ultimate terminations of the arteries, and the commencing roots of the veins. From the extreme tenuity of these vessels, it is impossible to indi- cate where the arteries terminate and the veins begin ; yet their con- tinuity with the capillary system has been repeatedly demonstrated, by throwing injections from the one into the other system ; and by microscopical observations made on the transparent parts of living ani- mals, as the mesentery and the web foot of frogs, and the tail of fishes. These facts are sufficiently substantiated by the observations of Mal- pighi, Leeuwenhoeck, Prochaska, and a crowd of others; yet there are anatomists who hold a contrary doctrine, and admit the paren- chyma of the ancients (an indefinable something, conceived, how- ever, to be spongy) as a point of termination for the arteries, and of commencement for the veins. Though the capillaries are all too fine to be seen distinctly without the microscope, yet they are found to have several gradations of size. The largest of them are those which only escape the naked eye, ex- periencing successive divisions, whereby their diameters are reduced from admitting a file of several globules of blood to the caliber of one globule only 4 The capillaries have also frequent anastomoses with one another. Sometimes the artery is simply doubled on itself, and immediately becomes a vein : on other occasions, several capillary arteries run into the same vein. The anastomoses finally end in a continuous intertexture of ves- * Bedard, Apat. Gen . f Anat. Atlas, Figs. 431, 432, 433. j; Bedard, loc. eit. CAPILLARIES. 189 sels, which is common to the arteries and veins both. Although the limits of the two sets of vessels, can not be precisely defined, so as to learn where one set ends, and the other set begins, yet the capil- lary system may be known by the greater uniformity of size in its vessels. Their diameter varies from the to the of an inch, but the medium measurement is from the tsVo to jtW of an inch. The following table will show the result of measurements upon injected preparations : Brain . - -I-* fT (TO according to Weber. Kidney a tO j--35o' cc Muller. Ciliary processes T‘T5t cc cc Mucous Membrane 7 of Large intestine $ 1 1 * TsTl LU 17^4: u Weber. Lymphatic Gland T8 IT 1 to Zt'oS cc cc Skin . T l'iS cc cc Inflamed Membrane 1 SZ 8 to 5 8 IB- cc cc As a general rule their diameter maybe stated at from one to five globules of red blood.* By the above, it will be seen that their diameter is sufficiently large for transmitting the blood discs. But the capillaries are de- cidedly smaller than any of the tubular structures of the body. The capillaries pass between the primitive fibrils of muscles and nerves, and form an intertexture around them, but as in other tissues of a very fine kind, they do not penetrate them, because those tis- sues have in their elementary filaments a finer diameter, than either the capillaries, or even the red globules of the blood. When the capillary communications are unduly enlarged, they constitute what has been called by Mr. John Bell the aneurism from anastomosis, a frequent mark in young children, and which, when it has developed itself fully, has a spongy structure resembling the erectile tissues, as the corpus cavernosum penis, &c. As there is a double circulation, so there is a double capillary system, one for the lungs and the other for the body generally : to these may be added a third, which exists in the liver between the hepatic extremi- ties of the venaportarum and the hepatic veins. The texture of the capillary vessels is too fine to admit of much ( * Beclard, loe. cit. 17 * 190 CIRCULATORY SYSTEM. scrutiny, but they appear as simple cylindrical excavations in the substance of the part to which they belong. This appearance has led many respectable anatomists to the conclusion, that they were absolutely destitute of walls. Gruithuisen saw the blood flowing in free spaces between the acini of the liver in the frog. Muller saw the same, in the liver of the larva of the triton. Wedmeyer came to the same conclusion, in witnessing the broad currents of blood with the small islets, between them in the lungs of the salamander. There are many other authorities on the same side. On the contrary, Leeu- wenhoeck, Haller, Spallanzani, Proc.haska, Bichat, Berres and Ru- dolphi, admit the existence of such membranous walls. Without the latter, we can scarcely account for the anatomical injection of fluids, passing from the arteries into the veins, without extravasation; and for currents of blood, crossing above and below each other, without mixing. Windischman has injected in the cochlea of birds, the blood vessels of a very soft plicated membrane, which, upon being dissolved in water, left a beautiful vascular net work with the meshes empty. Schwann has observed in the capillaries of the mesentery of the frog, an arrangement of circular fibres, and Muller after injecting the vessels of the kidney of a squirrel and macerating the glandular structure off, found the capillaries on the tubuli uriniferi, apparently independent vessels.* It is not improbable, that they may be uninterrupted continuations of the internal coat of the arteries into that of the veins. They have striking powers of extension and of contraction, and are easily irri- tated. An emotion of the mind, as a sentiment of shame or a feel- ing of resentment, quickly causes those of the face to become turgid with blood. Local stimuli cause congestions in them. Cold, the application of a weak acid, or fear, causes them to contract ; though, under the influence of the heart, they are less so than larger vessels. Their innumerable channels cause a comparatively languid circula- tion of the blood in them, for reasons rnentioned ; and' by furnishing it with more places of contact with their parietes, put it more under nervous influence than it is elsewhere. These vessels are not equally abundant in all the textures of the body. Their quantity may be ascertained by the redness which a part acquires by inflammation, as well as by fine injections: the latter proof is preferable, as, in the former, it is difficult to distin- * Mu-ller, Phys. p. 230. CAPILLARIES. 191 guish them from the extravasations which also occur at the same time. The celebrated injections of Ruysch, from their unusual minuteness, induced him to think that every solid portion of the body was vascular, yet he admitted that some portions were more vascular than others, thereby conceding to his antagonists, that some points at least were not formed by bloodvessels. In the microsco- pical examinations of living animals, for example the frog, it is seen that in their feet the smallest capillaries are separated by distinct intervals, while in the mucous membrane of the lungs the finest needle cannot have its point inserted without opening several of them.* The younger an animal is, the more vascular are its parts: but, on the contrary, as it advances in age, the proportion of parts not susceptible of injection increases, while the capillaries diminish in number. In cold-blooded animals, it is very evident that some of these capillaries, or arterio-venous communications, are large enough to admit a file of several red globules abreast, while others allow a single file only. The arrangement of the capillary net-work is for the most part uniform, the principal variation being in the size of the meshes, and in their being elongated or not. In muscles and nerves, the elon- gation is in the direction of the primitive fibrils, and the same may- be said of every tissue consisting of parallel filaments. In the in- testines, the capillary vessels being first arborescent, they anastomose very freely; in the placenta they resemble a tuft, in the spleen a sprinkling brush, in the tongue a hair pencil, in the liver a star, in the testicle and choroid plexus of the brain a lock of hair, in the Schneiderian membrane a fine trellis work. In the cortical portion of the kidney, there are glomeruli or small bulbs of vessels in the midst of the common anastomosis and fine vascular net-work; having wound itself up in that way, the artery then emerges on the other side, and is lost in the adjacent capillary tissue. This is said according to Teidemann to be particularly distinct in the triton and salamander. At the extremity of the villus of the human pla- centa a minute artery is directly continuous, with a minute returning vein. In the medullary portion of the kidneys, in company with the ducts of Bellini, the arteries and veins run parallel with these ducts * Beclard, Anat. Gen. 192 CIRCULATORY SYSTEM. anastomose across them forming elongated meshes, and finally ap- pearing on the papillm renculi, terminate in a fine net-work, sur- rounding the orifices of the uriniferous ducts. This vascular ar- rangement is frequently mistaken for the tubuli uriniferi themselves. Fig. 32. Distribution of Capillaries in the Villi of an Intestine. Fig. 33. Distribution of Capillaries around the follicles of a Mucous Membrane. The most attenuated capillary net-work exists in the lungs, and in the choroid membrane of the eye. The interspaces are some-, what larger in the iris and ciliary body. The mucous membrane of the intestines, especially of the veins, has its capillary net-work so fine as to form almost the entire structure apparently, when it is successfully injected. Bones, ossific cartilages, tendons, liga- ments, and the fibrous structures, generally are furnished with the fewest of them, and have the largest meshes. Fig 34. Distribution of Capillaries around the follicles of the Parotid Cland. Fig. 35. Capillary Network of the Nervous Centres. The nutrition of the body depends upon an alteration of exhala- tion and of absorption ; but it is still undetermined, whether there be any vessels whatever whose especial office is that of exhalation, and which produce the several secretions and exhalations. If there be such, they are generally designated by (he term exhalants, and their diameters are loo small to transmit the red globules of blood ; EXHALANTS. 193 their function is, consequently, to give passage to the serous particles only. palpebral conjunctiva. This subject has been much agitated by anatomists, and marshals the best authorities on both sides. Among the distinguished advo- cates in the affirmative, are Boerhaave, Haller and Bichat ; and op- posed to them, are Prochaska, Mascagni, and Richerand. The leading facts of the former are ; The microscopical observations of Leeuwenhoeck, who speaks of vessels admitting only serous globules ; the phenomena of inflammation, which render red, parts naturally white and transparent : the difficulty of conceiving how the nourish- ment of certain parts can be maintained, whose capillary system of red blood is so limited, in proportion to points not susceptible of it. The opinion of Mascagni and others to the contrary, is : That those exhalants, if they existed, should be seen readily, inasmuch as they are within the range of a microscope, whose powers enable one to examine a body much smaller than a red globule of blood; that in- jections should penetrate them, instead of being limited to vessels whose existence is sufficiently confirmed by examination in the living state ; that if during inflammation they do seem to be injected with red blood, the appearance is delusive, and depends upon the existing capillaries being dilated so as to receive more red blood than usual, upon the formation of new vessels, and upon sangui- neous infiltration; and as to membranes naturally white, as the con- junctiva, the colour depends upon the capillaries, while in a healthy state, being so small that they do not admit the red globules in a file sufficiently numerous to be perceived by the eye ; the globules Fig. 36. Fig. 37. Capillary Network in the mucous membrane of the Capillary Network in the choroid coat of the eye. 194 CIRCULATORY SYSTEM. being, probably, then conducted in a series of one only, or in a single fde, like a string of beads. It is, therefore, much more rea- sonable not to admit the existence of vessels which it is very doubt- iul whether any one has seen, unless we claim as such the vessels which, under ordinary circumstances, do not convey red blood, at least in a visible manner ; but are limited to the carrying of the liquor sanguinis, or, in other words, pure serous vessels, the exist- ence of which is affirmed by Muller. When a watery injection is pushed into a blood vessel, it in a little time shows itself as a fine dew upon the surface of the serous and mucous membranes ; in the cellular membrane, and elsewhere. According to many anatomists, it has gone through the system of exhalants, and, indeed, presents itself to sight in very much the same way that exhalation occurs in the living state. From the view which has just been taken, it becomes more probable, that this perspira- tion is execufed through the interstices or pores of the vessels. In the dead state it is merely a mechanical result, a simple straining of the fluid; whereas, in the living body it is a Antal function, continu- ally modified by the peculiar vital powers of the organ or membrane where it occurs ; and, therefore, presents itself under the form of the different secretions. The question of the exhalants being a distinct set of vessels, does not, however, appear to be one of much conse- quence ; because, if they do exist, they must be very short and very small : and the assumption of their existence does not throAV an) light upon the function of secretion. For the latter is still an incom- prehensible vital process, and as far as Ave have any idea about it, it is quite as easy to conceive of its being performed in the parietes of the capillaries, as in the mouths of a distinct set of vessels, whose length is too short to admit of an estimate. Besides the supposed existence of a general system of exhalant vessels, some anatomists have thought that there vvas a species of them acting particularly as nutritive vessels. According to Boer- haave, every part must, therefore, be vascular. Mascagni thought that the extreme arterial ramifications are not only furnished Avith exhaling, but also Avith nutritive porosities ; and that there are every where orifices of absorbing vessels, to contain the nutritive mole- cules. The theories of Bichat and of Prochaska, do not differ ma- terially from the latter. Whatever may be the mode of existence, and the route of nutriment to the several parts of the body, the opera- tions involved are entirely too subtle even for microscopic observa- TEXTURE OF THE ARTERIES. 195 tion. We, therefore, can only understand, in a general way, that the blood vessels deposite, and the lymphatics absorb, by invisible avenues in the cellular substance, the molecules of composition and of decomposition in our organs.* It is to this power that the name of vital force has been given, and especially that of the force of for- mation, ( nisus formativus.) The arteries, though commonly said to be cylindrical canals, are not exactly so, but, as they recede from the heart, increase somewhat in diameter, even where they do not send off any branches. In this way the arteries of the umbilical chord are evidently larger as they get nearer the placenta ; and the spermatic arteries of a bull as they get nearer to the testicle. Observations made on the carotid arteries of the camel, and of the swan, by Mr. Hunter,! tend to prove the same disposition in them. The vertebral arteries afford a striking example of the same. It is probable that the rule extends to all arteries throughout the system, but it cannot be ascertained with so much certainty, because of the close succession of branches which they send off. Arteries have within themselves a power of increase connected with the exigencies of the part to which they go ; thus, the uterine arteries increase much in their capacity during pregnancy, while the hypogastric, from which they are derived, augment inconsiderably, and the primitive iliacs notin an appreciable manner. In animals of the deer kind, whose horns are deciduous, the same augmentation of arterial trunks occurs while the horn is growing. Tumours are supplied in the same way. But in all these cases, after the exigency is passed, the vessels diminish to their primitive size. With the exception of the semi-lunar valves at the orifice of the pulmonary artery and of the aorta, there are no others in the whole arterial system. These valves permit the blood to pass in the direc- tion of the circulation, but not backwards, as they are closed imme- diately upon the cessation of the contraction of the ventricles. The tricuspid valve of the heart, and the semi-lunars of the pulmonary artery, are naturally not so perfect in their closure as those on the other side of the heart, but permit a small quantity of blood to retro- grade*! As life advances, the valves of the aorta are much disposed to ossification and derangements of different kinds, which render them much less perfect than those of the pulmonary artery. * Bedard, loc. cit. f On the Blood and Inflammation. f Hunter, loe. cit. 196 CIRCULATORY SYSTEM. CHAPTER II. Of the Tcxtnre of the Arteries. The arteries are composed of three coats, an external, a middle, and an internal. The External Coat, also called Cellular, is, in fact, condensed cellular substance formed into a cylinder. Its fibres run in every direction, so as to be perfectly interwoven with one another. The exterior periphery of this coat is continued into the adjacent cellular substance, but its internal face is united more closely to the middle coat ; not, however, so tightly as to prevent a slight sliding of the one upon the other, and to forbid their easy separation by a knife. Scarpa is not disposed to admit this as one of the coats of arteries, and says that it only serves as an exterior envelope, and retains them in their places. This coat manifests its fibrous character in not being disposed to secrete fat, and is more distinct in the large arterial trunks. It has considerable strength and elasticity, both circularly and longi- tudinally, and is remarkable for its whiteness. If an artery be sur- rounded by a tightly drawn ligature, the middle and the internal coats will be completely cut through by it, while the external coat remains entire. This coat, then, answers the purpose of a strong investing fascia,* in which respect it may be considered as a sheath to the proper arterial structure, though the term sheath is commonly applied to the cellular membrane on its outer side. The Middle Coat of the arteries is called the Muscular, the Proper, the Tendinous, and so on. It is of a light yellowish tinge, and de- creases continually in thickness, with but few exceptions, from the heart to the ends of the arteries; it is, however, proportionately thicker in the small arteries than in the large ones. Its fibres are circular, but do not individually perform the circuit of the vessel. They are parallel to each other, and adhere laterally by very slender ties. In the larger arteries, this coat may be divided into several laminae, though the division is entirely artificial. There are no lon- * Jones on Hemorrhage. TEXTURE OF ARTERIES. 197 gitudinal fibres whatever in it ; the consequence of which is, that an artery divested of its external coat, yields more readily in the direc- tion of its length than of its circumference. The middle coat has a firmness, whereby, even when an artery is emptied, the cylindrical shape is still retained. Its character seems to be the result of a mixture of elastic and of muscular properties derived from a state of tissue entirely peculiar; but which some ana- tomists have been very desirous of ranging under the head of mus- cles, others under that of ligaments, and a third, under both united. The celebrated John Hunter, whose observations were generally made with the most scrupulous attention to perfect exactitude ; were often repeated, so as to make one confirm another; and who has received that sanction of greatness in which one’s posthumous repu- tation becomes more exalted than the living ; bestowed much atten- tion on this subject. He was induced to believe that this middle coat was formed by a muscular lamina internally, and an elastic one externally; which distinction might be rendered evident by cutting a contracted artery through transversely , when the muscular coat would be found projecting beyond the other. He acknowledges, however, that he never could discover the direction of the muscular fibres ; though he supposed them to be oblique, because their degree of contraction was greater than a straight muscle could produce. The elastic contraction of an artery, is manifested both in the di- rection of its length and of its circumference ; for, when put upon the stretch in either way, it has the ability of returning to its original di- mensions after the distending force ceases. The muscular contrac- tion, however, only occurs in the circumference, and not at all in the length: by it the caliber of arteries is reduced to a very small diameter, if an animal be slowly bled to death. If, in this con- tracted condition, an artery be slit open longitudinally , the elastic coat will, at the cut margin, project beyond the other, which Mr. Hunter considers as another way of ascertaining the existence of the two tunics. But if this same artery be then stretched transversely, the muscular coat will project beyond the other ; for the reason, that if a muscle, after death, be elongated by force, it has no power of returning from that state, but will remain precisely as it is: whereas, elasticity being a property of matter enjoyed quite as fully in the dead as in the living state, the elastic coat of the artery returns to the medium condition. Mr. Hunter, with a view of satisfying himself on these several Vol. II.— 18 198 CIRCULATORY SYSTEM. points, had a horse bled to death, so as to obtain the vessels, at their minimum of contraction. A circular section of the aorta measured, at first, five inches and a half, and, on being stretched, it lengthened to ten inches and a half; being let alone, it contracted to six inches, at which it remained stationary ; the difference between six inches and ten and a half, was then the amount of its elastic power, while only half an inch of contraction was due to the muscular stratum, or, in other words, an eleventh of the whole. A section of the iliac artery, measuring two inches in circumfe- rence, on being allowed to contract after stretching, measured two and one-third inches; it, therefore, gained one-sixth the amount of its muscular contraction. A section of the axillary artery gained one-eighth — of the carotid, two-thirds — of the radial artery, doubled its primitive extent. From all which the inference was drawn, that the power of recovery in a vessel is greater, in proportion as it is nearer the heart, but lessens as the distance increases, which shows the decrease of elastic, and the increase of muscular power. The elastic coat gives a middle state to an artery, or has a con- tinued tendency to it ; if, therefore, the artery be too much dilated, it contracts it, and if it be too much contracted it dilates it, all of which is readily exemplified by a cylinder of gum elastic, which, whether compressed or dilated has only one state of repose, to which it immediately returns on being left to itself. Mr. Hunter supposed, that a certain degree of elasticity is continued to the very end of every artery, from this quality being better suited to sustain a per- manent resistance than muscular power ; as a pipe of lead, from its want of elasticity, finally becomes stretched and useless under the pressure of a column of water, whereas, one of iron, from being elastic, always reacts efficiently. It is this elasticity in the arteries, which causes the blood, at a little distance from the heart, to flow through them in a continued jetting stream when they are opened, although it is supplied to the aorta by interrupted strokes. In this way, as the artery is more distant from the heart, the stream becomes proportionately regular. “ The muscular power of an artery renders a smaller force of the heart sufficient for the purposes of circulation; for the heart need only act with such force as to carry the blood through the larger arteries, and then the muscular power of the arteries takes it up, and, as it were, removes the load of blood while the heart is dilating. In confirmation of this remark, it is observable in animals whose TEXTURE OF THE ARTERIES. 199 arteries are very muscular, that the heart is proportionably weaker, so that the muscular power of the vessels becomes a second part to the heart, acting where the power of the heart begins to fail, and increasing in strength as that decreases in power.”* After many discussions on the above, the present state of micro- scopical anatomy may be considered as leading to the following con- clusions. The fibres which make the middle coat of the arteries are identical with those of the ligamenta flava of the vertebral column and the analogous tissue, as the elastic ligamentous structure of the trachea, and the vocal or crico-thyroid ligaments of the larynx. This elastic tissue is every where distinguished by the great inequality in the size of its fibres, and by their anastomosing with each other. It is of a yellow colour, and its elasticity is well, though not fully pre- served in alcohol for an indefinite duration. This elasticity is an almost purely physical quality, both in the living and dead state, not absolutely so, but a near approach to it. Among the traits which distinguish the middle coat of the arteries from muscular tissue, is, its not contracting under the strongest elec- tric and galvanic stimuli, like muscles commonly. Nysten repea- tedly experimented with galvanism on the aorta of criminals just beheaded, but did not perceive the slightest contraction of its fibres. Similar experiments with the same results have been instituted by many others, and amongst them Muller, f The fibres of the elastic tissue are prismatic, or four sided, and have a diameter from ' . to —7- of an inch. In the coat of the arteries their course is more decidedly circular and parallel than in the ligaments. In both cases the heat of boiling water draws them up, but does not destroy their elasticity. The Internal Coat of the arteries is designated by the terms Ner- vous and Arachnoid. It is continued from the ventricles of the heart, in the left one of which it is of greater thickness. It is the duplication of this membrane with some fibres interposed, that com- poses the semi-lunar valves of the aorta and of the pulmonary artery. Its internal face is smooth, polished, and moistened wfith a kind of humidity which permits the blood to flow through with diminished friction. In the larger arterial trunks, some small longitudinal wrinkles are observable in it ; and when an artery has been cut through, as in amputation, it is disposed to retract in small trans- * Hunter, loc. cit. f Loc. cit., p. 217. 200 CIRCULATORY SYSTEM. Yerse wrinkles. It is, therefore, not very extensible, but has, accord- ing to the experiments of Sir Everard Home,* a considerable degree of solidity and strength. The internal coat of arteries possesses, to a limited extent, the elastic and other qualities of the middle, but it is generally considered as belonging to the class of serous membranes. A very delicate layer of epithelial scales with oval nuclei, according to Henle, occu- pies its internal face. This coat may be stripped with great facility from the aorta after steeping it for some time in alcohol. It is then found to be very thin and semitransparent. Ossifications of this membrane are very frequent after the age of sixty. In addition to the tunics mentioned, cellular substance, vessels, and nerves enter into the structure of arteries. The Cellular Substance is not abundant, and serves principally to unite the sides of the circular fibres to one another, and to join the internal to the middle coat. The Vessels ( Vasa Arteriarum ) consist both in arteries and in veins, and come from the adjacent trunks, instead of from those on which they ramify. They may be made very distinct by a fine in- jection, or by laying them bare in the living body ;■ when in a little time after exposure, they begin evidently to carry red blood, and to grow turgid as in inflammation. The difference in the colour of the blood distinguishes these arteries from the same kind of veins. Both arteries and veins may be traced very well into the middle coat, but not upon the internal, though the changes which occur in the latter, from disease and upon the application of ligatures, prove clearly that exhalation and absorption are continually going on there. For in inflamed arteries, an exhalation is seen upon their internal surface, and when a coagulum has been produced by ligature, it is finally absorbed. The Nerves of the arteries, according to Wrisberg and Beclard, are numerous and considerable, form around them a plexus resem- bling that of the par vagum around the oesophagus, and follow them into the interior of our organs, with the exception of the brain ; which has them only to its surface. They are proportionately more abun- dant in the aortic than in the pulmonary system ; also upon the smaller * Transactions for the Improvement of Medical and Surgical Knowledge, vol. i. TEXTURE OF THE ARTERIES. 201' than upon the larger arteries. The arteries of the head, of the neck, of the thorax, and of the abdomen, are supplied from the sympa- thetic nerve, while those of the extremities are supplied from the nerves of the spinal marrow. The passing of the blood through the arteries is accompanied with a pulsating motion, which, for the most part, is exactly syn- chronous with the contraction of the left ventricle, and depends upon an increased quantity of blood thrown into them at the moment. The dilatation of the artery may be both seen and felt ; “but were we to judge of the real increase of the artery by this, we should deceive ourselves; for when covered by integuments, the apparent effect is much greater than it really is in the artery itself ; for in laying such an artery bare, the nearer we come to it, the less visible is its pulsation ; and, when laid entirely bare, its motion is hardly either to be seen or felt. This apparent diastole of the artery is augmented in proportion to the solid matter covering it, whence tumours over large arteries have considerable motion given to them, and have often been supposed to be aneurismal. Arteries, in fact, during their diastole or dilatation, increase much more in length than in width, and are thrown into a serpentine course: instead, therefore, of the term diastole, it should rather be called the elon- gated state.”* Mr. Parry, of Bath,f has denied that the arteries dilate at all during their diastole: his opinion however, is peculiar, though, in an experiment performed many years ago upon the carotid artery of a calf, its correctness appeared to me then to be fully proved. There is no part of the human body which presents more fre- quent varieties, in different individuals, than the arteries. These varieties are found, in their place and manner of origin, in position, and in the number of their ramifications. They are comparatively rare in the trunks of the first order, more common in those of the second; and still more usual in those of the third and fourth. From these causes, discrepancies are continually found in the descriptions of the most approved authorities, and must last so long as writers repose upon a partial experience, instead of referring to what has been most generally observed. * J. Hunter, loc. cit. f Experimental Inquiry on the Pulse, 1816-1819. 18 * 202 CIRCULATORY SYSTEM. CHAPTER III. Of the Texture of the Veins. The veins, from their duty of receiving the blood in all parts of the body from the extreme arteries, and returning it to the heart, by successively collecting it into the two venae cavse, may be more appropriately compared to the roots of a tree, than to its branches. The variations in them, as well as their anastomoses, are more fre- quent than in the arteries. They are more numerous than the arteries; for, in addition to two venous trunks attending each artery wherever the structure of the part is intended for locomotion, as in the extremities, and in some places upon the trunk of the body, there is a very abundant class of veins which are superficial or subcutaneous, and which, when filled properly with injecting matter, form a fine vascular net-work over the whole surface of the body.* These superficial veins, in some places, form trunks even larger than such as attend the arteries, and especially in the extremities. Besides the excess in number, the veins which attend the arteries (Fence Comites) have a capacious- ness which, in many cases, is double that of the latter. From these several circumstances, it results that the area of the venous system vastly exceeds that of the arterial. In some cases the veins follow precisely the course of the arteries, one for one, as in the greater number of the viscera of the abdomen, where they have common points of entrance and departure. Some- times two arteries discharge into one vein, as in the penis, the clitoris, and the umbilical chord ; sometimes they pursue a course entirely different from the arteries, as in the pia mater. For the most part they are less tortuous than the arteries. The veins, when injected, assume a cylindrical shape, yet they differ materially from the arteries, in having much thinner coats, and in being so pliable that they collapse by their own weight. In the lower extremities, however, near the feet, and upon them ; as the veins sustain the pressure of a long column of blood, they have * Pauli Mascagni Anatom. Magna. Pisis, 1823, TEXTURE OF THE VEINS. 203 additional thickness and strength, so as to approximate them more to the arterial structure. This provision will be found occurring in most places where they have much duty to perform. “ They are similar to the arteries in their structure, being com- posed of an elastic and muscular substance ; the elasticity preserves them in some degree in a middle state, although not so perfectly as it does in the arteries. The muscular power adapts the veins to the various circumstances, which require the area to be within the middle state, and assists the blood in its motion towards the heart.”* The External Coat is thinner and not so strong as that of the arteries ; in other respects, the resemblance is sufficiently close not to require any particular comment. The Middle Coat, near the entrance of the larger veins into the heart, is distinctly muscular. f It is formed of soft extensible fibres, many of which, when the vein is held up to the light, appear longi- tudinal, while the most internal are circular; there are difficulties, however, in the separation of these fibres, which prevent their course from being accurately ascertained. Admitting this coat with the exception of its muscular ingredient near the heart, to be of the same tissue, that is the elastic ligamentous which prevails in the ar- teries, yet the filaments composing it are much more decidedly in- termixed, according to my personal observations. Bichat and Meckel assert, that the whole of them are longitudinal, and that there are none circular. This coat in the human subject, is much thicker in the system of the ascending than of the descending cava ; it is also thicker in the superficial than in the deep-seated veins. In some subjects it is much better developed than in others. In certain parts of the body it is entirely deficient, as in the sinuses of the dura mater, and has its place supplied by this membrane ; the same deficiency exists in the sinuses of the bones. The Internal coat is more delicate and extensible than the corres- ponding one of the arteries, is less liable to rupture, and less disposed to ossification. It is thrown into a considerable number of duplica- tions, forming valves. Each valve is of a semicircular shape ; is con- * Hunter, loc. cit. f Beclard, loc. cit. 204 CIRCULATORY SYSTEM. nected by its curved edge to the A r ein, while the straight edge is loose, and turned towards the heart. When the veins are injected back- wards, these valves may be forced in the larger trunks, and give them a knotted appearance. The valves are commonly in pairs, but in certain veins, as the crural and the iliac, there are three of them together ; very rarely do they amount to four. In some in- stances there is but a single one ; this arrangement is more frequent at venous orifices, as the great coronary vein of the heart, the vena cava ascendens, the vena azygos. They are frequently found reticu- lated as if they had been lacerated, whence it has been supposed that the fibres which cross the sinuses of the dura mater are an elementary approach to them. The valves are more abundant in the superficial than in the deep- seated veins, but they do not exist every where. There are none in the branches of the vena portarum, excepting the vasa brevia: none in the spine, in the umbilical vein, the cervical veins, the kid- neys, womb, ascending and descending cava, or in the median vein. The valves are proportionately more abundant in the lower extre- mities. From the tenuity of the parietes of the veins, the blood may be readily distinguished circulating through them. Their coats, like those of the arteries, are vascular, or have the vasa vasorum. The arteries come from the nearest small trunks, while the corresponding veins do not empty immediately, but secondarily, into the trunk, whose parietes they supply. They are well furnished with veins. Their elasticity, both transversely and longitudinally, is well marked ; but they are not so extensible in the latter direction as the arteries, while they are more so transversely. There can be no doubt of their spontaneous powers of contraction, for it is abundantly proved by their diminishing much in volume upon the application of cold ; moreover, when a venous trunk, distended with blood, is intercep- ted by two ligatures, and then punctured, it empties itself entirely and rapidly. The circulation in the veins is produced, in a principal degree, by the contraction of the heart; their own contraction may also favour this motion, as w r ell as lateral pressure from contiguous. parts. As the movement of the blood in the smaller arteries is so uniform as to be almost without pulsation, so the latter disappears entirely in the veins. It is not clear that this circumstance depends exclusively on THE BLOOD. 205 the friction experienced by the blood in passing through the capil- laries, but is probably rather owing, as Mr. Hunter has suggested, to the veins receiving their blood from different arteries, some of whose channels are more circuitous than others, and, consequently, their blood arrives at different times. The momentum of the heart, then, even if it did impinge upon those channels, would not be syn- chronous upon the venous trunk, but would be divided in such a way as to produce a tremour or confused motion. The larger veins, however, have near the heart a pulsation during the contraction of the auricles, arising from the arrest of their circulation at the moment. During inspiration, the vacuum created in the thorax hurries on the blood to the heart, but in expiration it is somewhat impeded.* It has sometimes happened, that a large vein near the heart being opened by accident or an operation, a strong inspiration has caused the introduction of air, which, being carried to the heart, has pro- duced instant death. It occurred in Paris to the celebrated surgeon Dupuytren, and has occurred to others. CHAPTER IV. Of the Blood. The Blood is the fluid from which is derived the aliment for the growth and repair of all other parts of tire body. It is renovated by the accession of new nutriment introduced into the system through the process of assimilation, and it has also a large increase from the decomposed materials of the several textures of the body. * This ancient observation has lately been renewed, with additional interest and details by M. Barry of Paris. See a Report of MM. Cuvier and Dumeril, concerning the Influence of the Atmosphere on the Circulation of the Blood, in the Philadelphia Journal of the Medical and Physical Sciences, for July, 1826. M. Barry has probably assigned too much importance to this influence, as it is certain that the circulation may go on very well where no vacuum is pro- duced at intervals in the thorax; for example, in the foetus, in incubation, and in fish. 206 CIRCULATORY SYSTEM. A copious excretion takes place from it through the different glands and emunctories. The precise manner of its formation is im- perfectly understood ; it would at least seem to require no very complex apparatus for its formation, as it is generated in the area vasculosa of the germinal membrane of an egg, before the organs exist in a distinct state. The Blood, in the human subject, and in many animals, is of a red colour. It is about the consistence of thin size, has a peculiar smell, a nauseous and slightly saline taste, and is somewhat heavier than water ; its specific gravity being about 105, and its temperature in the living body is from 96 to 98° of Fahrenheit. The method devised by Mr. Valentin to determine the exact proportion and quantity of blood in an animal has the merit of greater exactitude than any other, and seems to have solved this question with an accuracy almost unexceptionable. The weight of the animal is first ascertained ; a certain quantity of blood is then re- moved, and evaporated to dryness ; the weight of the residuum is then ascertained. A known quantity of water distilled is upon drawing the first blood, thrown in by the same orifice and allowed to mix with the general mass of blood. This done, a second quantity of blood equal to the first is withdrawn, evaporated to dryness also, and the w r eight of its solid residuum ascertained. The quantity of the residuum in the two parcels, determines the entire amount of blood in the animal by the following method : Thus, let two ounces of blood first drawn yield twenty-four grains of solid matter ; and upon the injection of one pint and a half of water let two other ounces of blood yield only twenty-one grains of solid matter. Then multiply the quantity of wmter injected by tw r enty-one and divide by three, (the difference in the tv'o parcels of solid residuum :) the result will determine the whole quantity of blood in the animal after the extraction of the first two ounces. Thus 24 ounces multiplied by twenty-one and divided by 3, gives 168 ounces. Tried by this method, a dog of 531bs. weight is ascer- tained to have ten and a half pounds of blood, and forty-two and a half pounds of other materials in his composition, or one part of blood, and four parts nearly of other constituents. There are some circumstances which may affect the absolute ac- curacy of the experiment, but the conclusion is so nearly satisfactory that Mr. Valentin in taking the dog as the standard for the human body fixes the quantity of blood in a man at thirty-four and a half, THE BLOOD. 207 and in a woman at twenty-six pounds : the proportion in the first being, blood, 1 ; other parts, 4-30 : and for the female, blood, 1 ; and other parts, 4-93. A remarkable fact was observed in an emaciated and diseased dog, that the relative quantity of blood to other parts was the same as in health. If the blood be examined microscopically while circulating in an animal, or immediately upon being drawn, it is seen to consist of red particles or globules swimming in a transparent fluid. This transparent fluid is the Liquor Sanguinis or Plasma, which is formed of serum and fibrin, the latter being in a state of solution in the serum. This state of solution has been proved by Muller in filter- ing through a porous paper the blood of a frog recently drawn : from the size of the red particles they are in this process left behind and the serum and fibrin passing through together, the fibrin forms a coagulum* to itself. The proportion of fibrin in the human subject to the entire mass of blood would seem to be very small, as in the experiments of Lecanu he found fibrin, when dried, to form from about one and a third to seven parts, in one thousand. In a spontaneous coagulation the fibrin attaches itself to the red globules and is found with them, while the serum separates and is squeezed out. So long as it continues to circulate, or while it is still flowing from an opened vessel, the blood has, to common inspection, the appearance of a homogenous fluid ; yet, after it has been drawn a few minutes, and permitted to remain at rest, it assumes a thick ge- latinous condition, expressed by the term coagulation, and by which it ceases to be any longer fluid. The coagulation begins on the sur- face of the mass, and by a thin pellicle, which shows itself in three or four minutes ; commonly at the end of twenty minutes the coagu- lation is complete throughout, but this rule varies according to the state of the body at the moment ; and the coagulation is more pro- tracted when the quantity of blood is large and has been drawn through a large orifice, than where it is small, and has been evacu- ated through a small orifice. This change has scarcely taken place, when a spontaneous separation follows, whereby it is resolved into the watery part, or Serum, and into a thick condensed mass called Cruor or Crassamentum. The serum first shows itself on the sur- * Physiology, p. 124. 208 CIRCULATORY SYSTEM. face of the coagulum, in small drops, which quickly increasing in number and size, finally run together, and form a mass of fluid ex- ceeding considerably that of the crassamentum. The separation into serum and crassamentum, though sufficiently evident after a few hours, yet requires some days for its complete accomplishment ; for the coagulum still continuing to contract, expels more and more of the serum. The peculiar complexion of the blood depends upon the red glo- bules. They do not seem to be an indispensable constituent, as many animals are entirely deprived of them, and such as naturally are possessed of them, may have their quantity very much reduced by repeated bleedings. The colouring matter is generally an in- gredient of the crassamentum, so that the whole of the latter has a red appearance ; yet there are some conditions of the body in which a spontaneous separation of it takes place, more or less completely. For example, in inflammatory diseases the blood does not coagulate so soon as in health ; and the red globules, from being naturally heavier than the other constituents of the crassamentum, subside to its bottom and leave it of a white semi-transparent colour. It is this white part upon which depends the whole property of coagu- lating, and which has been called coagulating lymph, or fibrin. We have, therefore, three constituents of blood manifested by its own spontaneous changes ; the Serum, the Red globules, and the Coagu- lating lymph. As in inflammation the red particles subside to the bottom before the coagulation of the fibrin begins, the fibrin is seen more largely on the surface of the clot, and by a strong contraction in coagulating draws the top of the clot into the form of a saucer. There is, how- ever, always a little fibrin left throughout the clot, and holding the red particles together; with the exception of a few which maybe found at the bottom of the vessel, perfectly untrammelled by it. It was ascertained by Sir C. Scudamore that inflammatory blood con- tained more fibrin than healthy blood. Coagulation, contrary to popular opinion, is not assisted by cold, but rather retarded by it : heat assists it.* If the heat be raised to 120°, blood will coagulate five minutes sooner than if left at its na- tural standard, and even sooner than if its temperature be reduced to 50°. If blood be frozen quickly, before it has time to coagulate, * Hunter on the blood. Hewson. SERUM OF THE BLOOD. 209 on being thawed it returns to the fluid state, and will coagulate after- wards. The contact of air does not produce coagulation. The late Dr. Physick, in order to ascertain this point conclusively, took a glass tube, which had a stop-cock at each end, and attached one of its ends to the vein of a dog. A current of blood was then conducted through the tube, and while it was flowing, the far stop-cock was closed, and immediately afterwards the other ; thus, a column of blood was ob- tained which had not touched the air. After permitting it to remain a proper time, the tube was broken asunder, and the blood found coagulated as usual. Rest is not indispensable to the process, for blood, if shaken in a vial, will still coagulate. The division of the blood into small masses expedites coagulation. Therefore when it flows slowly from the blood vessels, falls from some height, or runs for a distance over the surface of a dish, it coagulates sooner than under opposite circumstances. The latter are then auxiliary to the blood manifesting the sizy coat, one of the concomitants of inflam- mation ; because if the coagulation be very rapid, it will prevent the constituents of the crassamentum from separating from one another, by entangling the red globules, in the coagulating lymph. After death the blood is coagulated in the veins, though not so perfectly or generally as is supposed, for there are no subjects which do not bleed from their large veins, when the latter are opened. The coagulation of the blood is sometimes delayed for many hours after death. I have in examining the head of a patient who died of phthisis pulmonalis found the blood which came from the jugular veins, in a thin fluid state and of a bright Vermillion colour ; and upon being spread out on a plane surface it coagu- lated like recent blood. There are many modes of death which prevent entirely the coagu- lation of the blood in the vessels, for example, where life is destroyed by a paroxysm of excessive anger; by electricity ; by lightning; by a blow upon the stomach ; by certain fevers of a typhoid character. Many chemical articles prevent its coagulation on being mixed with it. SECT. I. — OF THE SERUlI OF THE BLOOD. Serum is common to the blood of all animals, and is considered, by Mr. Hunter, to be more abundant in such as have red globules. Vol. II.— 19 210 CIRCULATORY SYSTEM. It is, generally, of a lighter specific gravity than the crassamentum. I have, however, often seen the latter floating in it, which shows the contrary in some instances. Though its separation commonly de- pends upon the coagulation of the latter, yet that process is not in- dispensably necessary, as was once witnessed, by Mr. Hunter, in a lady, in whom the serum was disengaged from the crassamentum, while the latter was yet in a fluid state. The phenomena of dropsy, also, prove the same point. Serum though very fluid, is not so much so as water. It is of a light yellow or straw colour, varying, somewhat, in different subjects. It contains a large quantity, about eight per cent., of albumen, or matter resembling the white of an egg. It also consists of water, about ninety per cent.; of soda uncombined, and of several of the salts of soda, the presence of which may be manifested in several ways. For example, when exposed to a heat of 140 degrees of Fahrenheit, it becomes opaque, and at 160 or 165 coagulates firmly. During this process, a great deal of air is disengaged from it. It is also coagulated by spirits of wine, by all the mineral acids, by cor- rosive sublimate, and by many other articles. They all prove the presence of albumen. Mr. Brande considers the albumen as an albuminate of soda, and that its fluidity depends on the excess of soda ; when, therefore, the latter is removed or neutralized by an acid, the albumen coagulates. Under the action of the Galvanic pile, like the influence of heat, the soda produces mucus, by blend- ing with a part of the albumen ; and the remainder of the latter, not being able to retain its fluidity after the abduction of the soda, coagulates. This mucus or serosity is, probably, the part which Mr. Hunter speaks of as retaining its fluidity when other portions of the serum are coagulated by heat. It is observed in meat either roasted or boiled, and comes from it as a thin, limpid fluid, somewhat tinged with the red globules. The older the animal is, the greater is its comparative quantity : in lamb, there is scarcely any of it, whereas, in mutton five or six years old, it is abundant ; the same rule seems to hold in regard to the human subject. This serosity, or mucus, is coagulable by Goulard’s extract.* The serum is not always transparent, but sometimes wheyish and thin : when it settles, it often throws up a white scum like cream and called Seroline. This more frequently occurs in pregnant women, * Hunter, loc. cit. COAGULATING LYMPH OF THE BL'OOD. 211 though it is not confined exclusively to either sex, or to any known condition of body. The specific gravity of the globules composing this seroline varies ; for though it generally floats on the surface of * the serum, it does not always: it also sometimes swims, and, on other occasions, sinks in water. It has been erroneously considered as chyle not yet assimilated, or as absorbed fat or oil. It is, proba- bly, this substance which presents itself under the form of micro- scopic globules in the coagulum of serum ; and, when serum has been kept for several days, is deposited in the form of globules at its bottom. These globules present a singular motion of ascent and descent in the serum ; upon the application of heat to it by holding in the hand. The presence of soda uncombined in the serum, is readily ascer- tained by an infusion of red cabbage, (Brassica oleracea,) or the juice of the flag, ( Iris versicolor ,) which are both made green by it. Sul- phur combined with ammonia, is also found in it. Owing to the presence of sulphur, serum has the effect of blackening silver when left in it, and also has its power of dissolving the oxydes of mercury, iron, copper, and other metallic preparations. The serum contains a portion of fatty matter allied to the same substance in other parts of the body, and which may be extracted with ether. It also contains animal principles, whose general de- signation is that of extractive matter, and some of the ingredients of which are lactic acid and osmazome. They are believed by Ber- zelius to be the effete parts derived from the continual decomposition of the body, and which are conveyed away through the excretions. There are some other salts besides those mentioned which are found in serum.* The serum has a specific gravity in health of about 1030, and con- tains about 9J per cent, of solid matter including the albumen — the seroline and the mineral constituents. SECT. II. — OF THE FIBRINE OR, COAGULATING LYMPH OF THE BLOOD. Coagulating lymph, or fibrine, when circumstances are suitable lor collecting it free from the red globules, offers the appearance of a * See Henle, Anat. Gen. t. i. p. 483. 212 CIRCULATORY SYSTEM. semitransparent body of a very light drab colour ; it is elastic and strong, and when subjected to the microscope, has the appearance *of muscular fibres, by being composed of colourless globules. Like muscle, it also, when macerated in water, resolves itself into those globules before it putrefies. If the blood, while flowing from an animal, be collected, and, at the same moment, stirred around and around with a rough stick, the fibrine will gather upon the latter in a fibrous form, so as to resemble a mass of entangled and knotted packthread. The fibrine may be afterwards washed almost white, and, at any rate, so as to clear it entirely from the red globules. The fibrine, when dried, loses greatly in its bulk and weight, by the evaporation of the serum from it, so that the proportion which it seems to bear to the whole mass ofblood, is much less considera- ble than one would suppose, from seeing it in the simple coagulated state. The coagulating lymph of the blood being common, probably to all animals, while the red particles are not, w r e must suppose it from this alone to be the most essential part ; and, as we find it capable of undergoing, in certain circumstances, spontaneous changes, which are necessary to the growffh, continuance, and preservation of the animal ; while to the other parts we cannot assign any such uses ; we have still more reason to suppose it the most essential part of the- blood in every animal.”* In examining a drop of blood with a deep object glass, there is apparent in the field of vision one or two white globules, the average diameter of which is about j-g ols of an inch. They are either smooth or granulated on the surface, semitransparent and spherical, or nearly so. They differ from the blood discs, or red globules, in being nearly the same in all animals, they are more obscure in the human subject and mammalia, but are very distinct in reptiles, birds, and fishes. They w r ere first seen by Spallanzani in the Salamander, and then noticed in the blood of Mammalia, by M. Mandl, a few years ago ; they are considered by the latter as produced by a coagulation of fibrin, and, as identical with the globules of pus and mucus. By Mr. Gulliverf they are called nucleated cells or organic germs of fibrin: he is, however, doubtful of their perfect identity with the particles quoted by Mr. Mandl. * Hunter, loe. cit. f Appendix to Gerber’s Gen. Anat., p. 14. RED GLOBULES OF THE BLOOD. 213 Besides the above, Mr. Gulliver has seen a white matter existing in abundance in the form of spherules, of from 4,5^ to t-ttt of an inch. The animals in whom it was witnessed had died chiefly of tubercular phthisis, and he, therefore, is inclined to think this a pa- thological appearance. Besides milky serum, which is sometimes found in the blood after a repast, corpuscles of a peculiar kind have been noticed in the splenic and supra renal veins, which are supposed to come from the spleen and from the capsulse renales. SECT. III. — OF THE RED GLOBULES OF THE BLOOD.* * * § The impression at the present day in regard to the red globules, or Blood discs, as they are also called, is that they are flattened bodies of a circular shape and having a thickness from a fourth to a half of their breadth. To see them of this figure, they should be ex- amined in fresh serum, a weak solution of common salt, or in thin syrup ; if water alone be used they contract into a spheroidal shape. In birds, reptiles, and fishes they are elliptical. In the lower orders of animals the disc appears to have a central nucleus, which projects in a rounded form above the general surface of the disc. In the siren, according to Professor Owen, the disc consists of from twenty to thirty spherical granules. But very great doubt exists in regard to the nucleus in man and the mammalia gene-' rally. Authority of the highest kind may be quoted for either opi- nion. Mullerf says he has seen it, Carpenter is inclined to admit it, Gulliver J denies, and Wagner who once admitted it, now holds it as uncertain, Henle§ says, that drying renders the nuclei of' the corpuscles of the blood very obvious, and that in calcining them, the wrecks of the nucleus and feeble traces of the envelope, are dis- cernible. This is the result of his observations on the lower orders of vertebrata, but in the human subject and mammalia, lie evidently disinclines to the opinion of nuclei existing in the blood discs. He says, in one place that the pretended nucleus is only the depressed * Anat. Atlas, Figs. 434, 435. f Page 115. Appendix to Gerber, p. 15. § Encyclop. Anat., vol. vi., p. 466, Paris, 1843., 19 * 214 CIRCULATORY SYSTEM. centre of the disc, and in another place, he says, that in all his ex- periments, it has scarcely ever occurred to him to see any trace of nucleus. — Numerous opinions for and against may thus be cited, and while the question is agitated by the best observers, others may very properly await their decision. Under common observation the light transmitted through the centre of the blood discs is more intense than elsewhere, which gives to them the appearance of being perforated or annular. By many, each blood disc is considered, notwithstanding the diffi- culties of determining such minute points of structure in the human body, to consist in a capsule, a contained matter, and a nucleus in its centre. The advocates of this opinion, also view it as a de- termined fact, that the blood discs conform in their general character with the isolated cells, which constitute the whole of the simplest plants, each having an independent life of its own. The improvements of the compound microscope have enabled us to determine with accuracy, the diameter of the blood discs or red globules. It appears now that there is no absolute or uniform size to them in the same mass of blood, but that they vary much in this respect, some being about -- u 1 — of an inch, and others about the ■ 3 J . Other animals than man present them of a larger or smaller size, thus in the fish called Squalus Squatina, they are about the — t — of an inch, whereas, in the cat they measure about — J — . The different magnitudes in man are supposed to be accounted for by admitting them as cells in various stages of growth and evo- ution. Their size has no relation to the magnitude of the animal, lor in the Mouse they have three times the diameter of those of the Musk deer. The proportion of blood-discs varies very much in different persons : the average is about 140 in one thousand parts of blood in the male, but it may go to 186 or descend to 110 without ill health. In the female the average is about 112 in the thousand, but it may fall to 71 or rise to 167 in common health. In chlorosis it has been found as low as 27, and not unfrequently is at from 40 to 50 parts in the thousand.* The blood corpuscles, or blood discs, are larger in the embryo than in the adult, Mr. Prevost has seen that they were in the foetal goat twice the size of such as belonged to the maternal. Mr. Barry * Carpenter’s Elem. of Physiol. p. 309. RED GLOBULES OF THE BLOOD. 215 asserts, that the germinal state of every tissue is that of corpuscles, having the same appearance with the blood corpuscles, and Mr. G ulliver, that they are much more abundant in inflammatory diseases than in health. It has been already observed that the red globules are the heaviest part of the mass of blood, and are, therefore, always disposed to subside to the bottom of the crassamentum, though from the quick coagulation of the latter, they can seldom do it fully before they become entangled in it, and thereby fixed to a certain place. They do not invariably retain their form, but are readily dissolved in water. They are, of course, insoluble in serum. Urine does not dissolve them; neither does a solution of muriate of soda, of sal ammoniac, epsom salts, nitre, diluted sulphuric or muriatic acid : the latter, however, deprives them of colour. The solution of red globules in water is manifested by the mixture becoming of a fine transparent red, and the process takes place almost immediately. On the contrary, when the globules refuse to be dissolved, a muddy mixture is formed. When they are dried in serum, and afterwards soaked again in it, they do not resume the regular form. They have more substance than the coagulating lymph, for they do not lose so much of their bulk by drying. The analysis of the blood corpuscles presents two proximate prin- ciples, hoematosin and globulin. The first amounts to about or is of the mass when the globules are dried, and when burned, it yields a quantity of peroxide of iron. The colouring ingredient of the red globule, is commonly con- sidered to be the peroxide of Iron. In some recent experiments of Mr. Scherer, this belief has been assailed, if not invalidated, by his observing, that though the iron be removed, yet alcohol can be made intensely red by boiling in it the globules left after such ex- traction. “ It is difficult to determine by what means the iron, or the sul- phur, or the elementary principles of the calcarious earths, obtain an existence in the blood. If these materials were equally diffused throughout the surface of the earth, we might easily conceive that they were introduced through the medium of food. But as this is not the case, as some regions, like New South Wales, at least, on this side the Blue Mountains, contain no limestone whatever, and others, no iron or sulphur, while all these are capable of being ob- tained apparently as freely from the blood of the inhabitants of such 216 CIRCULATORY SYSTEM. regions, as from that of those who live in quarters where such ma- terials enter largely into the natural products of the soil: it is, per- haps, most reasonable to conclude that they are generated in the laboratory of the animal system itself, by the all-controlling in- fluence of the living principle.”* The red globules, according to the opinion of Mr. Hunter, from not being pushed into the extreme arteries, where the coagulating lymph reaches, and from not being found in all animals, do not con- tribute to the growth and to the repair of the system. But they seem to be connected with strength, in such animals as have them, as the strength acquired by exercise increases their proportion and occa- sions them to be carried abundantly into parts which previously, from a debilitated state, received them but partially if at all. This fact is w r ell known to graziers, who keep their quantity in certain animals, as veal, reduced by quietude and frequent bleeding. Their source is not understood, though many conjectures on the subject have been hazarded. Leeuw r enhoeck asserted, that they had the power of self-repro- duction, and this statement has received additional confirmation by the observations of Mr. Barry. f According to him the propagation takes place by the parent globule splitting into about six others, the development starting from its nucleus. As there is a continual de- composition going on, each disc or cell has a definite period of existence, and while some are dying others are coming into exis- tence. Mr. Hunter’s opinion was, that they do not appear to be formed: in those parts of the blood already produced, but rather to rise up in the surrounding parts : as, in the incubated egg, they exist in the form of a zone, composed of dots, previously to the formation of vessels. The above sentiments of a very celebrated man, it may be well enough to preserve, though they seem to be in contradiction wfith present views, except the appearance at first in the incubated egg. The analysis of Mr. Lecanu, in regard to all the elements, organic, and inorganic, entering into the composition of the blood, is regarded as having a high claim to confidence. The blood w T as obtained in tw T o parcels, each from a stout healthy man: * Good, Stud, of Med. f Phil. Trans. 1840, and 1841. RED GLOBULES OF THE BLOOD. 217 Water 780.145 785.590 Fibrin 2.100 3.565 Albumen 65.090 69.415 Colouring matter, (globules) . 133.000 119.626 Fatty crystallizable matter 2.430 4.300 Oily matter 1.310 2.270 Extractive matter, soluble in water 1 .790 1.920 and alcohol ‘ Albumen combined with soda. 1.265 2.010 Chloride of Sodium u potassium Carbonates 4 of Potash and Soda Phosphates > “ “ Sulphates ) “ “ \ 8.370 7.304 Carbonates, Lime, and Magnesia ) Phosphates, Lime, Magnes. and Iron > 2.100 1.414 Peroxide of Iron ) Loss . * 2.400 1.000.000 2.886 1.000.000 Denis found the proportion of water in man’s blood to vary from 805 to 732 in a thousand parts, and in woman from 848 to 750. According to Lecanu, the quantity of water bears no determined relation to the period of life ; Denis, however, found it more abun- dant in children, and in aged persons. In sanguine temperaments the blood has less water in it than in lymphatic. The proportion of albumen varies from 57.890 to 78.270, and is about the same in the two sexes. The crassamentum consisting of the red globules and of fibrin, varies from about 68.349, to 148.450, and in men it is more abundant than in women, in the proportion of 32.980 parts in the thousand.* * For very erudite and interesting Essays on the blood in regard to its cor- puscles, liquor sanguinis or plasma, quantitative analysis, development, re- generation, and other points connected with it, a full account of which would be too long for the present work ; the reader is referred to the writings of Hewson and Hunter, in the last century. Henle’s Gen. Anat. p. 457, et seq. Paris, 1843. Muller’s Physiology, by Baly, p. 109, et seq. vol. i. London, 1842. Principles of Human Physiology, by W. B. Carpenter, p. 464, et seq. London, 1842. Wagner’s Elements of Physiology, by Willis, p. 230. London, 1842. Animal Chemistry by Dr. J. F. Simon. Phila. 1846. ' 1 X BOOK VIII FART IS. OF THE SPECIAL AMATOIY OF THE CIRCULATORY SYSTEM. CHAPTER, I. Of tlie Heart and Pericardium.* The Heart, (Cor,) the centre of the circulation, is situated in the thorax, between the sternum and the spine ; being bounded on its sides by the lungs, and below by the tendinous centre of the dia- phragm. It is a hollow muscular organ. The heart is of a conoidal shape, but flattened on the surface which lies upon the diaphragm. This flat surface is on a horizontal line with the lower end of the second bone of the sternum ; the base of the cone is towards the vertebrae, and looks obliquely backwards to the right side, while the apex is about the junction of the left fifth rib with its cartilage. Its common weight is about six ounces. Its greatest length, to wit, that from the apex to the base, is about five and a half inches, four of which are taken up by the ventricles : its base is about three and a half inches in diameter. The heart is divided into four cavities ; tw T o auricles and two ven- tricles : the places where the partitions are placed between these cavities are marked on the surface of the heart by fissures or depres- sions, sufficiently distinct to be immediately recognised. The two auricles form the base of the heart, the ventricles constitute its body, and the anterior end of the left ventricle, by being extended somewhat * Anat. Atlas, Figs. 439 to 447, inclusive. 220 CIRCULATORY SYSTEM. beyond the right forms the apex. The right auricle and the right ventricle, are the two cavities which are nearest to the right side of the body, while the left auricle and the left ventricle are the two cavities nearest to the left side. It will, however, be understood, from the general observations already made, that the relative situa- tion of these cavities is such, that the right ones are in front of the others, and present obliquely forwards to the right side, while those on the left look obliquely backwards to the left side. This position of the heart makes it encroach more upon the left cavity of the thorax than it does upon the right ; from which cause its pulsations may be very easily distinguished where the left ribs join their car- tilages, while on the right side of the sternum there is scarcely ever a perceptible pulsation. Being placed between the right and the left pleura, in the mediastinum, it is surrounded by its own proper capsule called the Pericardium. The Pericardium is covered on its sides by the Pleurae, and re- poses on the tendinous centre of the diaphragm, to which it adheres by close compact cellular substance, particularly at its periphery. When the latter attachment is cut through, a separation of the re- mainder is easily effected. Behind, the pericardium is opposite to the bronchia and to the oesophagus. The pericardium does not adhere to the heart, except at the base of the latter; it is, therefore, a loose capsule in, by far, the greater part of its extent. It not only surrounds the heart, but also the roots of the large arteries and veins connected with it. Thus, it includes the aorta, as high up as the great vessels proceeding from its arch ; from the latter, it passes to the trunk of the pulmonary artery, and also includes it, causing the aorta and the pulmonary artery to lie close together. The posterior face of these vessels is not covered so high up as the anterior face. The pericardium also invests the descending vena cava for an inch above its junction with the right auricle : it likewise invests the trunks of the pulmonary veins, and tire ascending cava as it rises above the diaphragm. The pouches which it forms at the base of the heart, in passing from one of these vessels to another, are the cornua of some anatomists. It cannot be considered as pierced for the passage of these vessels, but is lost insensibly on their parietes ; being continued into the cellular cover- ing of the arteries, in accompanying them to a great distance.* * Sabatier, Trait. d’Anat. vol. ii. p. 284. PERICARDIUM. 221 The pericardium is a double membrane, or consists of two layers, an internal and external one. The external membrane, to which the preceding description is especially applicable, resembles strongly the dura mater, but is thinner; it is, therefore, white, semi-transpa- rent, fibrous, and inelastic. Its thickness is greater on the sides, than below where it rests upon the diaphragm; or above, where it goes along the great vessels : its fibres are irregularly disposed and interwoven, but many may be traced longitudinally. The Internal layer lines the external, and gives the polish to its' cardiac surface ; it is then conducted along the surface of the seve- ral vessels that have been mentioned, to the heart, over the whole of which it is spread, and adheres to it by cellular substance, fre- quently containing much adipose matter: it also causes the heart to have a smooth shining surface. This is a very delicate thin serous layer; and secretes a fluid, transparent and somewhat unctuous, like that of the joints, but not so consistent ; which lu- bricates the surface of the heart and permits it to play freely within its pericardium. This fluid, in a natural state, seldom exceeds a tea-spoonful, though two ounces, or a little more, are not considered sufficient evidence of a pathological state : its augmentation consti- tutes a dropsy. After death, we find the pericardium lying loosely around the heart, from the vacuity, and consequently diminished bulk of the latter; but while the circulation is going on, the heart fills and distends it. A striking resemblance is observable between the condition of the pericardium and the moveable articulations. Its external layer corresponds with the strong fibrous capsule that passes from one bone to the other ; while the internal is the syno- vial bag, which scarcely assists in the strength of the apparatus, but secretes a fluid to render motion easy. Several instances are on record of a total absence of pericardium. The Right Auricle {Auricula Dextra , Anterior) is an oblong cu- boidal cavity. It is joined at its posterior superior angle by the de- scending vena cava, and at its posterior inferior angle by the ascend- ing vena cava. The structure of the auricle, between these wet points, seems to be only a continuation of that of the veins. These veins enter with a direction slightly forwards, so that their columns of blood are not directly opposed to each Other. In front of this continuation of the two veins, the auricle is dilated into a pouch Vol. II.— 20 222 CIRCULATORY SYSTEM. called its Sinus: the upper extremity of the latter, just in front of the descending cava, is elongated into a process with indented edges, and has some general resemblance to the ear of an animal, from which it is probable that the term Auricle has been derived. The exterior surface of this cavity is smooth arid uniform, but its internal surface is varied at several places. About midway be- tween the orifices of the two cavae is found a transverse prominence, the Tuberculum Loweri, which is occasioned by the continuous structure of the veins meeting at an obtuse angle. This cavity is separated from the left auricle only by a thin septum, which is com- mon to the two auricles. On the septum, below its middle, is a superficial circular depression, the Fossa Ovalis; it is more distinct above than below, and varies much in its dimensions. It is sur- rounded by an elevated margin, composed of muscular fibres, and called its Annulus, or the Isthmus of Vieussens. The septum of the auricles is thinner at the fossa ovalis than elsewhere, and is fre- quently perforated by one or more foramina. I have, in several instances, seen a hole there, large enough to transmit the finger. On such occasions, from the valvular arrangement of the opening, it is probable that the blood of the two auricles is still kept distinct. The fossa ovalis always presents this foramen in the foetal state. Just below the fossa ovalis is found the Eustachian valve, con- sisting in a duplication of the lining membrane of the auricle. It is crescentic, but varies much in its dimensions and shape. Its left extremity commences at the left inferior margin of the annulus ovalis ; it then extends itself along the front of the orifice of the as- cending cava, where the latter is connected with the auricle, but never to an extent sufficient to arrest the circulation there. Some- times it is reticulated at its margin, and half an inch wide ; on other occasions, it is scarcely developed. Its loose edge looks upwards, and to the right side. Its office in the foetus is clearly, according to the opinion of Sabatier, to direct the blood of the ascending cava through the foramen ovale. In the adult, it may, on the general principle of venous valves, oppose itself to the introduction of re- fluent blood into the ascending cava; but this office cannot be very exactly performed, as the valve is frequently scarcely visible at that age. At the lower part of the right auricle, just to the left of the Eustachian valve and very near it, is the orifice of the large coro- THE HEART. 223 nary vein of the heart: it is protected by a small semi-lunar valve, ( Valvula Thebesii ,) formed also by a duplication of the lining mem- brane of the auricle. This orifice will admit a quill of common size very readily. At the anterior semicircumference of the descending vena cava, there is an oblique fasciculus of muscular fibre, with which the ad- joining musculi pectinati are connected, and which in its contrac- tion will answer, to a limited degree, as a valve or barrier, in pre- venting the reflux of blood from the auricle into the cava. A smaller fasciculus of muscular matter also exists along the base of the Eu- stachian valve, and will execute the same office for the ascending cava. The office however of neither is perfect, but limited to a partial state of occlusion. Between the right auricle and ventricle is a round hole, of more than an inch in diameter, for the passage of the blood ; it is the Ostium Venosum. Its margin, on the auricular side, is smooth and rounded. The parietes of the right auricle are formed by muscular fibres. On the Sinus these fibres are collected into small transverse fasci- culi, called Musculi Pectinati, from their resembling the teeth of a comb. These fasciculi, though slightly united by other fibres, yet leave between them deep interstices, by which the external and the internal membrane of the heart come into contact. The parietes of the auricle are about one line in thickness. Its mus- cular structure is continued for a short distance, on the two venae cavse. There are several orifices of small veins on the internal surface of this cavity, and in greater abundance around the fossa ovalis ; they belong to the system of coronary vessels, and are the foramina Thebesii. The Right Ventricle ( Ventriculus Dexter , Anterior.) The general form of this cavity, which receives the blood from the right auricle, is that of a triangular pyramid, curved somewhat backwards, and having its base downwards. It forms the greater part of the ante- rior surface of the heart, and is about three lines in thickness. It is bounded on its posterior face by the left ventricle, from which it is completely separated by a thick septum. The internal surface of this cavity is covered by muscular fasciculi, of very irregular shapes and dimensions, designated under the term ColumnEe Carnese : some of the latter go from one side to the 224 CIRCULATORY SYSTEM. other ; others contribute to the mechanism of the valvular apparatus between it and the right auricle ; but the greater portion is employed in forming a complicated reticular texture over the internal face of the ventricle. Those connected with the valve vary from four to eight in number : they are rounded, of different lengths and sizes, and detach from their projecting extremities several small rounded tendinous chords, ( Chorda tendinece ,) which are inserted into the floating edge of the valve. These chords form an intertexture among themselves. The Valve, between the ventricle and the auricle, consists in a duplicature of the lining membrane of the ventricle, arising unin- terruptedly from around the ostium venosum, at the left margin, which is there somewhat tendinous. This valve is called tire Tri- cuspid, ( Valvula Tricuspis, Triglochis,) because its loose margin is divided into three points or processes. One of these points, which is at the anterior external margin of the orifice, is much larger than the o&er two and more distinct in its boundaries. The edges of these processes form a sort of reticulated work along with the adjoining ends of the tendinous chords : by this arrange- ment they are always kept expanded and in the cavity of the ven- tricle. The opening for the pulmonary artery is placed above the ostium venosum ; at this point, the cavity of the ventricle, instead of being reticulated, is made smooth, for the more ready transmission of blood. The orifice of the pulmonary artery is round, and about twelve lines in diameter ; it is furnished with three valves, called from their shape Semi-lunar or Sigmoid. Each valve is a semi- circular plane, formed from the lining membrane of the artery, and attached to the latter by its semi-circumference. The diameter of the plane is loose, and, instead of being straight has each semi- diameter of a curved or festooned shape : in the centre of its edge is a small cartilaginous body, the Corpuseulum Aurantii, which when the valve is thrown down by the reaction of the artery, comes in contact with the corresponding bodies of the other valves, so' that they serve as mutual abutments. The Corpuseulum is some- times scarcely discernible. Between the outer face of each valve and the artery there is a pouch, attended with a slight dilatation of the artery, and called the Sinus ValsalvEe. Between the coats of each valve there is an additional fibrous substance, for the purpose of strengthening it. THE HEART. 225 The Pulmonary Artery, immediately after its origin, goes up- wards and backwards to the under part of the curvature of the aorta, and there divides into two trunks, one for each lung. These trunks separate widely, and from the middle of their fork proceeds a liga- mentous substance, the remains of the Ductus Arteriosus of the foetus, to the aorta posteriorly to the origin of the left subclavian artery. The right Pulmonary artery is both longer and larger than the left, and passing transversely behind the aorta and the descending cava, then penetrates the substance of the lung to be distributed as men- tioned. The left pulmonary artery passes to the lung in front of thp descending aorta. Though the pulmonary artery is quite as large as the aorta, its parietes are thinner. The Left Auricle, ( Auricula Sinistra, Posterior ,) in the natural situation of the heart, is concealed by the right auricle and the ven- tricles. Its figure is more regularly quadrangular, or square, than that of the right, and into each of its angles is introduced a pul- monary vein, there being two on each side. Sometimes, however, the latter join together previously, so that the two have but a com- mon orifice. Its tip, or ear -like portion, is situated at the left side of the pulmonary artery, and is longer, narrower, more crooked, and more notched at its margins than the corresponding portion of the right auricle. The parietes of this cavity are muscular, and somewhat thicker than those of the right ; they are smooth and uniform, both exter- nally and internally, with the exception of its appendix or ear-like portion, in which the musculi pectinati prevail. The term Sinus Venosus or Sinus Pulmonalis of anatomists, only means that part of the cavity into which the pulmonary veins empty. The septum be-, tween the auricles, when viewed on this side, has the place of the fossa ovalis marked out principally by its diaphanous condition. Occasionally, there is some appearance of the valve which once existed there. At the inferior part of the anterior side of this cavity is found the. opening between it and the left ventricle, also called Ostium Veno-„ sum ; it is circular, and rather more than an inch in diameter, re-, sembling strongly the corresponding orifice of the right side of the. heart. The Left Ventricle ( Ventriculus Sinister, Posterior) in the shape. 20 * 226 CIRCULATORY SYSTEM. of its cavity resembles a long ovoidal or conical body. Its parietes are generally three times as thick as those of the right ventricle , amounting to about eight lines: it is thicker, however, at its inferior than at its superior part, as it gradually decreases in approaching the aorta.. Its internal surface is arranged on the same principle with that of the right ventricle, being roughened by the presence of numerous fleshy columns ( Columnce Cameo) some of which are connected with the valvular apparatus between it and the left auricle : others form an intricate reticular texture on its sides, and a few pass from one side to the other. As this surface approaches the orifice of the aorta, it becomes smooth, so that no impediment may be afforded to the passage of the blood. The Ostium Venosum, on the side of this cavity, has its margin looking tendinous, and furnished' with a duplicature of the lining membrane that surrounds it. This duplication, by being severed on its loose edge into two divisions, obtains the name of Mitral Valve, ( Valvula Mitralis.) Its margin is secured from being pushed into the left auricle by numerous chordae tendineae, which are at- tached by their other extremities to four or five columnae carneae pro- jecting from the surface of the ventricle. The whole internal ar- rangement of this cavity indicates a great increase of strength over that of the right side : in the robustness of its fleshy columns; the number and size of its tendinous chords ;■ and the greater thickness of its valve. The upper division of the mitral valve is placed im- mediately below the orifice of the aorta, and is considerably broader than the other, so that when it opens to admit blood, it is in some measure thrown over the aortic orifice. There is less of an inter- texture among the tendinous chords here than on the right side of the heart: they cluster more, and, owing to the breadth of the ex- tremities of the fleshy columns, are more parallel. The Septum of the Ventricles is of considerable thickness, being formed almost exclusively by the continuation of the fibres of the left ventricle. Where the large columns carnese elevate themselves on its surface, its thickness is increased. Its shape is somewhat triangular. It forms a round projection into the right v r entricle, while its other surface, which presents to the left, is concave to the same degree. It is rather thinner as it approaches the auricular septum than elsewhere. Its fibres near the apex are less closely connected to each other. THE HEART. 227 The orifice of the Aorta is furnished with three Semi-lunar Valves,* which, in the mode of their arrangement, correspond precisely with those of the pulmonary artery. They are, however, thicker, and the Corpuscula Aurantii are larger. The Sinuses of Valsalva, at- tended with a slight dilatation of the artery, exist in the same way. Just beyond the margin of the right and of the left valve, are ob- served the orifices of the two coronary arteries. The orifice of the aorta is somewhat tendinous, which marks out the distinction of structure between it and the ventricle. Of the Texture of the Heart. The Heart, with the exception of the serous membrane which lines its cavities, called the Endocardium, and of the serous lamina of pericardium which covers its surface, consists almost entirely of muscular fibres. The sides of the auricles, as stated, are much thinner than those of the ventricles. In the right auricle, the stratum of muscular fibres is uniform in its venous portion, but on the sinus is arranged into the parallel fasciculi called the Musculi Pectinati ; a circular fasci- culus surrounds the orifice of the descending cava. In the left auricle, the stratum of muscular fibres forms a uniform layer, and is also thicker than on the right side. These fasciculi commence on the pulmonary veins and run transversely across the auricle, with the exception of the more deeply seated, which are irregular, and crossed upon each other. The septum of the auricles is also formed by a muscular stratum. * Mr. Erskine Hazard has furnished me with the following estimate on the action of these valves : — If the diameter of the artery be put = 10, the length of the superior edge of the valve will also Tig'- 38. be 10. The arc occupied by the valve will be 10.47 = 120° of the circle. The valves, w hen open, will either assume the form at B, or that of the double chord of 60°, as at A. In either case,- being .47 shorter than the arc, they cannot come in contact with it, and must, therefore, leave room for the blood to get behind them, and depress the valves. For the same reason, they cannot close the orifice of the coronary arteries. The chord of 120° would be 8.67. 228 CIRCULATORY SYSTEM. In the ventricles, the superficial fasciculi observe a spiral course, and many of those belonging to the left ventricle may be traced over the right ; as the fibres are more deeply situated, they become shorter and more interwoven. In the septum, between the ven- tricles, the fibres of the two cavities are much interlocked ; but with some trouble may be partially separated. The fibres of the colum- ns carnese are too irregular in their course, to admit even of a gene- ral description. It would appear, however, that they are a conti- nuation of the superficial spiral fibres of the ventricles which penetrate into the interior of the heart at its apex, and leave there a small foramen which is closed only by the pericardium externally, and the lining membrane of the heart. M. Gerdy asserts, that all the fibres of the heart arise from, and are inserted into, the tendinous rings forming the ostia venosa and the orifices of the large arteries ; having in the mean time traversed the course which is peculiar to the several fasciculi, accordingto their being superficial, in the middle, or deep- seated.* All the cavities of the heart are lined by a serous membrane ( Endocardium ) resembling that of the blood vessels. It is the du- plicature of this with some intermediate fibrous tissue, which in each case makes the valves, the thickness of w T hich is proportionate to the requirements of the circulation. Of the Blood Vessels of the Heart. The Heart is furnished with both arteries and veins, which belong to its nutritious system. The Arteries called Coronary, arise, as observed, from the trunk of the aorta, somewhat above the margins of the semi-lunar valves; so that when the latter are applied against the aorta, the orifices of these arteries are still visible. The Right Coronary Artery begins above the anterior valve, and passes to the right, beneath the pulmonary artery ; it then shows itself in the upper part of the fissure, between the right auricle and right ventricle, and follows the course of this fissure to the flat side of the heart. It detaches, as it goes along, several small branches, * For a very detailed exposition of the structure of the Heart, see Wolff Act. Acad. Petrop. 1781 ; and Gerdy, Journal Complementaire du Diet. des. Sc. Med. vol. x. p. 97. VESSELS OF THE HEART. 229 which come off at right angles from it. One set of these branches is distributed upon the right ventricle, and another set upon the right auricle. Small branches are also sent from it to the root of the pulmonary artery, and to that of the aorta. The Left Coronary Artery begins above the left semi-lunar valve. While its root is still obscured by the pulmonary artery, it divides into two principal branches, of which the anterior runs in the fissure on the upper part of the septum of the ventricles to the apex of the heart, and in this course distributes branches to the right and left ventricle : those to the right anastomose with the branches of the right coronary artery, which go to the same ventricle. The other branch goes along the groove, on the septum, between the left au- ricle and left ventricle, and reaches the under surface of the heart; and in this course distributes many branches to the left auricle and left ventricle, both on their upper and under surfaces. It anasto- moses freely with the branches of the trunk that run along the upper part of the septum. In consequence of the frequency of the anastomoses between the two coronary arteries, injecting matter thrown into one very readily finds its way into the other. The Coronary Veins receive the blood, which is distributed by the coronary arteries through the substance of the heart. The Great Coronary Vein ( Vena Coronaria Maxima Cordis ) is formed by the union of several trunks, which run from the apex towards the base of the heart. One of them begins at the apex, goes along the superior fissure of the septum of the ventricles, and then winds to the left side, between the left auricle, and the left ventricle : while in the latter position, it is joined by several trunks coming from the left ventricle and the left auricle : it, finally, emp- ties into the lower part of the right auricle, just in front, as men. tioned, of the orifice of the ascending cava; being there covered by its own valve. The Lesser Coronary Vein (Vena Cor on. Minor Cordis) lies in the inferior fissure of the septum of the ventricles. It begins at the apex, and, going backwards, collects the blood from the fiat surface 230 CIRCULATORY SYSTEM. of the heart, principally on the right ventricle. It discharges into the great coronary vein, just before the latter terminates in the au- ricle. Besides the preceding veins, some of a smaller size exist on the right ventricle and auricle, and about the root of the aorta and pul- monary artery, and empty by several orifices into the right auricle. There are also some veins of a still smaller size, which open into all the cavities of the heart by little orifices, called the Foramina of Thebesius: by Mr. Abernethy they are considered as being larger when the lungs are diseased.* The Nerves of the Heart come principally from the cervical ganglions of the sympathetic, and follow the course of the coronary arteries. It has been doubted whether these nerves are actually distributed in the substance of the heart, from the presumption, that as they cannot be traced beyond the third order of branches of the coronary arteries, they are limited to them. But, as the ramifica- tions of the sympathetic are bestowed exclusively upon the branches of the circulatory system, Meckel has very properly suggested, that the heart being also supplied with nerves from the same source, it follows that there can be no departure from the general rule, as the heart is nothing more than the fibrous portion of the blood vessels more completely developed. While the circulation continues, as both auricles contract at the same instant, whereby the blood is thrown into the ventricles, and as immediately afterwards the ventricles contract simultaneously also ; whereby the blood is forced into the aorta and the pulmonary artery, so it is the contraction of the ventricles which causes the heart to strike against the parietes of the thorax. For, as was first pointed out by Dr. W. Hunter, the blood which is forced through the large arteries, by extending them diminishes their curvature, or brings them more into a straight line, in which effort the heart bounds up from the tendinous centre of the diaphragm. The filling of the auricles, while this is going on, also assists in protruding the heart forwards. The French anatomists assert, that during the con- traction of the ventricles, their extremity is elevated or bent up- wards on the body of the heart, which will also increase the mo- mentum of the stroke against the thorax. * London Philosophical Transactions, 1798. BRANCHES FROM THE ARCH OF THE AORTA. 231 CHAPTER II. Of the Arteries. SECT. I. — THE AORTA AND THE BRANCHES FROM ITS CURVATURE. The Aorta is the trunk of the arterial system. Having arisen from the superior posterior end of the left ventricle, its root passes be- neath the pulmonary artery, and is entirely concealed in front by it. Keeping to the right it emerges at the base of the heart, between the right auricle and the trunk of the pulmonary artery, being bounded on the right side by the descending cava. Continuing its ascent it forms a curvature with the convexity upwards, and the summit of which rises to within eight or twelve lines of the superior edge of the sternum. This curvature is in front of the third and fourth dorsal vertebrae, and its direction is nearly marked out by a line drawn from the anterior extremity of the third right rib, to the posterior end or tubercle of the third one on the left side. In this course, therefore, the aorta passes over the right pulmonary artery, across the left bronchus, and applies itself to the left side of the spine, about the third or fourth dorsal vertebra. It is this curvature which ob- tains the name of the Arch of the Aorta, ( Arcus Aortce.) Near its origin, where the aorta is still within the pericardium, it has very commonly, especially in persons advanced in age, a di- latation, which is called the Great Sinus to distinguish it from the lesser sinuses, or those of Valsalva. This dilatation is useful in diminishing the resistance arising from the curvature of the aorta, to the current of blood ; or rather it is a provision for doing away with the effects of friction, as by it a larger current of blood becomes a compensation for diminished velocity. The ascending portion of the arch is to the right of the vertebral column, the descending por- tion to tire left, and the middle or horizontal part goes in front of the trachea i 232 CIRCULATORY SYSTEM. The aorta, in its descent down the thorax, is placed in the pos- terior mediastinum, and is covered on one of its sides, by the left pleura, while the other side is in contact with the left surface of the bodies of the dorsal vertebrae. At the lower part of the thorax it in- clines towards the middle line of the vertebrae, in order to reach the hiatus aorticus of the diaphragm, through which it penetrates to the abdomen. In the abdomen it descends in front of the lumbar ver- tebrae, somewhat on their left side ; and at the intervertebral space between the fourth and fifth vertebrae of the loins, or somewhat above, it ceases, by being divided into two large trunks, the Primitive Iliacs ; one for each lower extremity, and the corresponding side of the pelvis. In this course of the aorta, from the heart to the loins, it first gives off the branches which supply the head and the superior extremities ; then, those which supply the sides of the thorax : afterwards in the abdomen, it detaches the trunks which supply the viscera and the sides of the latter cavity. The Coronary Arteries are, strictly speaking, the first branches of the aorta, but as they belong especially to the heart, their descrip- tion is associated with it. In all the space between them and the superior convexity of the aortic arch no branches are given off; but as the aorta is crossing the trachea three considerable trunks arise from it, which are distributed upon the head and the upper extremi- ties principally. They are, the Arteria Innominata, the Left Primi- tive Carotid, and the Left Subclavian. The Arteria Innominata is first in its origin : in ascending from left to right in front of the trachea, and behind the Transverse vein, it crosses the trachea very obliquely ; is from an inch to an inch and a half, and sometimes, though rarely, two inches long, when it divides into the right subclavian and the right primitive carotid. The left primitive carotid arises from the aorta, close upon the left border of the innominata ; frequently, indeed, from a part of it. The left sub- clavian artery, at its origin near the left carotid, generally leaves a distinct interval of one, two, or three lines. The relative situation of these trunks is particularly alluded to in the account of the supe- rior mediastinum. The last two are, of course, longer than the corresponding trunks of the right side, by the whole length of the arteria innominata. With the exceptions connected with their mode BRANCHES FROM THE ARCH OF THE AORTA. 233 of origin, the arterial trunks of the two sides are exactly alike, and have the same mode of distribution. The Common Carotid Artery ( Carotis Primitiva ) being a branch of the innominata on the right side, and of the aorta on the left, goes up the neck to terminate just below the cornu of the os hyoides. In the early part of its course, the right one is more inclined outwardly than the left, owing to its origin from the arteria innominata in front of, and to the right side of the trachea; whereas, the left, ascends almost vertically. At the lower part of the neck, just above the sternum and the clavicle, the carotid is covered by the sterno-hyoid and thyroid muscles, and by the sternal portion of the sterno-cleido-mastoid. It is crossed obliquely on a line with the lower part of the thyroid cartilage of the larynx, by the omo-hyoid muscle. It lies at the side of the thyroid gland, the trachea, the larynx, the oesophagus, and pharynx, in front of the transverse processes of the cervical vertebrae, and the longus colli muscle ; having on its outer margin, but some- what in front, the internal jugular vein, and the pneumogastric nerve enclosed in the same sheath, and the sympathetic nerve behind. At the side of the larynx, the carotid is very superficial, and with the exception of being crossed by the omo-hyoideus muscle, it is only covered by the platysma myodes and the integuments. The Carotid having got as high as the space between the os hyoides and the thyroid cartilage, but varying slightly in different subjects, there divides into two large trunks, the Internal Carotid, which goes to the brain and to the eye : and the External Carotid, which is principally distributed upon the more superficial parts of the head and neck. The first of these trunks is placed behind the other, and bends outwardly at its root : it is generally the largest in infancy, on account of the proportionate volume of the brain at that age ; it is also swollen at its root, so as to form a sinus there, re- sembling an incipient aneurism. No branch, except in the abnor - mons cases, is given off from the common carotid between its origin and bifurcation. Vol. II.— 21 234 CIRCULATORY SYSTEM. SECT. II. — OF THE CAROTIDS, AND THEIR BRANCHES.* The Internal Carotid, ( Arteria Carotis Interna,) in the adult, is smaller than the external, and extends from the larynx to the sella turcica. It ascends between the external corotid and the vertebrae of the neck, being in front of the internal jugular vein, and having the pneumogastric nerve at its outer margin : as it gets on a level with the base of the lower jaw, it is crossed externally by the digastric and the stylo-hyoid muscles ; it is immediately afterwards concealed in the subsequent part of its ascent by the ramus of the lower jaw. Having gone along the most internal or deeply seated margin of the parotid gland and of the styloid process of the temporal bone, at the side of the superior constrictor of the pharynx, it then penetrates into the cranium through the carotid canal of the temporal bone. It is slightly flexed between its origin and the carotid canal : just before it reaches the latter, it curves upwards and forwards. The first part of its course through the canal is vertical, afterwards it goes horizontally forwards ; and to escape from the canal it has once more to ascend almost vertically, which brings it to the posterior extre- mity of the Sella Turcica. On the side of the Sella Turcica it again passes horizontally forwards through the cavernous sinus ; and at the anterior clinoid process it once more ascends, and, having pene- trated the dura mater, it reaches the brain. In this passage, through the carotid canal, it is attended by the upper extremity of the sympathetic nerve, and gives one or more small branches to the petrous bone ; it also gives a few branches to the dura mater and to the nerves about the cavernous sinus. But, for the full exposition of the distribution of the internal carotid, see the arteries of the Brain and of the Eye. The External Carotid Artery [Art. Carotis Externa ) extends from the termination of the primitive carotid, to the neck of the lower jaw. In the early part of its course, where it is situated in front of the in- ternal carotid, and between the pharynx and the sterno-mastoid muscle, it is comparatively superficial, being only enveloped by its sheath, and covered by the platysma myodes and the skin. Just above this place it is crossed externally by the hypoglossal nerve, * Anat. Atlas, Figs. 448 to 453 inclusive. CAROTIDS, AND THEIR BRANCHES. 235 which detaches the descending branch along the front of its sheath and of that of the primitive carotid. Somewhat above this nerve, it is also crossed externally by the digastric and the stylo-hyoid muscle, and lies there on the side of the superior constrictor muscle of the pharynx, near the tonsil gland. About its middle, it is crossed internally by the stylo-glossus and the stylo-pharyngeus muscle; it then ascends through the substance of the parotid gland, between the ramus of the lower jaw and the ear, to its ter- mination. Several very important branches are given off from the external carotid ; they are as follow : The Superior Thyroid Artery ( Art . Thyroidea Superior) arises from the external carotid, about a line above its root, and is distri- buted to the larynx and to the thyroid gland. It goes at first inwards and forwards on the side of the larynx, being covered by the omo- liyoideus muscle, and by the platysma myodes ; it then descends under the sterno-thyroideus to the upper margin of the lobe of the thyroid gland. In this course it performs several flexuosities, of con- siderable variety in different individuals. The Laryngeal Branch comes from it near the superior margin of the thyroid cartilage ; this branch glides in between the thyro-hyoid muscle and the middle thyro-hyoid membrane or ligament ; after a short course, it penetrates the latter, and is then distributed in a great number of small twigs to the muscles and to the lining membrane of the larynx. A small trunk, either from the laryngeal branch, or from the thyroid artery itself, is spent upon the crico-thyroid muscle, and traversing the front surface of the middle crico-thyroid ligament, anastomoses with its fellow : small twigs from this branch penetrate to the interior of the larynx through the middle crico-thyroid liga- ment. Sometimes this crico-thyroid ramus is superior in size to the one above, in which case it principally supplies the interior of the larynx. The Thyroid Branch is the continuation of the principal trunk : it penetrates into the substance of the thyroid gland, and divides into two ramuscules, one of which goes along the posterior face of the lobe of the gland, and anastomoses with the inferior thyroid ; the other goes along the upper margin of the gland, and anastomoses with its congener of the opposite side. The thyroidal artery is split up into a great many branches in the substance of the gland, it also 236 CIRCULATORY SYSTEM. sends small branches to the pharynx, oesophagus, and the little mus- cles on the front of the neck. The Lingual Artery [Art. Lwgualis ) comes from the external carotid at the distance of from six to twelve lines above the superior thyroid, and goes to the tongue. It is concealed in the early part of its course by the digastric and the stylo-hyoid muscles ; it then penetrates the hyo-glossus muscle just above the cornu of the os hyoides, or goes between it and the middle constrictor of the pharynx ; it then ascends between the hyo-glossus and the genio-hyo-glossus muscle ; advancing forwards, it is placed between the latter and the sublingual gland, and, finally, reaches the tip of the tongue. The lingual artery sends off the following branches. At the root of the tongue one or more trunks arise from it, the Dor sales Linguce which go to the base of this organ, the tonsils, the palate, and the epiglottis; one of these branches is called the Inferior palatine. A little farther on, the lingual detaches another branch, the Ramus Sub- lingualis , which, advancing between the mylo-hyoid and the genio- hyo-glossus muscle, and above the sublingual gland, sends a great many ramifications to these parts and to the lining membrane of the mouth ; it is sometimes a branch of the facial. The Ramus Raninus, is the continuation of the lingual; it advances between the lingualis and the genio-hyo-glossus muscle, to the tip of the tongue, distri- buting continually its twigs on each margin, and ends there by anas- tomosing with the corresponding artery of the other side. The Facial Artery ( Arteria Facialis , Maxillaris Externa ) arises from the external carotid two or three lines above the lingual, and is spent principally on the side of the face below the eye. It is of considerable size, and very tortuous; its root is concealed by the stylo-hyoid and the digastric muscle, and it is traversed externally by the hypo-glossal nerve. It goes forward v i Lin theangle of the lower jaw, and above the submaxillary gland, but very much con- nected with it : it then mounts over the base of the maxilla inferior, at the anterior margin of the masseter muscle, and afterwards shapes its course, in a serpentine manner, to the internal canthus of the eye, passing between the muscles and the integuments of the face. In this course, the facial artery sends off the folio wing branches: As it passes by the submaxillary gland it sends several twigs to it : previously it also sends several little branches to the contiguous CAROTIDS, AND THEIR BRANCHES. 237 muscles, as the internal pterygoid, digastric, and so on ; but they are too small to be of much consequence. The Submental branch arises, then, on a level with the base of the lower jaw; it advances forwards under the origin of the mylo-hy- oideus, and above the anterior belly of the digastricus. It sends several branches to these muscles, some of which anastomose with the ranine artery; behind the symphysis of the jaw it anastomoses with its fellow, it then mounts over the chin, to which and to the lower lip it is distributed, anastomosing there with the inferior coro- nary artery of the mouth, and with the inferior maxillary which comes out from the anterior mental foramen in the lower jaw. When the facial artery has got upon the face, it sends backwards a small branch to the lower part of the masseter muscle. Somewhat above this it sends forwards a branch called the Inferior Labial, which is distributed upon the middle of the chin. When it gets on a level with the corner of the mouth, but sometimes lower down, it sends forward, under the depressor anguli oris, the Inferior Coronary Artery, to the lower lip, which frequently supplies the place of the inferior labial entirely ; but when the latter is large, the coronary is small in proportion : a few lines higher up the facial sends forward a third branch, the Superior Coronary, which goes to the upper lip. These coronary arteries are very tortuous, and are distributed by many branches in the substance of the lips : by anastomosing with their congeners of the other side, they surround the mouth com- pletely. The superior coronary artery, as it passes under the nose,, sends upwards one or more small branches to the integuments of its orifice and septum. After this, the facial artery, in ascending towards the internal canthus of the eye, sends a branch to the ala nasi, and another to anastomose with the infra-orbitar artery. It, finally terminates at the internal canthus of the eye by anastomosing with the branches of the ophthalmic, which come out there upon the side of the root of the nose. Several ramuscules, which are too small to merit spe- cial description, are given by the facial to the integuments and mus- cles of the face, and to the lower eyelid. The Inferior Pharyngeal Artery [Art. Pharyngea Inferior , ascen- dens ) is one of the smallest of the original branches of the external carotid, and generally arises opposite to the lingual ; but there is. much variety in the latter respect, it being sometimes higher up or. 21 * 238 CIRCULATORY SYSTEM. lower down, and not unfrequently a branch of one of the other arte- ries, instead of being an original trunk. It ascends on the side of the pharynx, between the external and the internal carotid, and is covered by the stylo-pharyngeus muscle. It is principally distri- buted on the constrictor muscles of the pharynx, and upon their lining membrane. But one of its branches, called the Posterior Meningeal Artery, ascends through the posterior foramen lacerum of the cranium, between the jugular vein and the pneumo-gastric nerve, and is distributed on the contiguous dura mater. The Occipital Artery (Arteria Occipitalis ) is a very considerable trunk, which comes from the external carotid, generally opposite to the facial, and is spent upon the integuments, on the back part of the head. At its root, it is deeply situated in the side of the neck, below the parotid gland, and has the internal jugular vein and the par vagum on its inside. It goes obliquely backwards, in ascending along the posterior belly of the digastricus between the transverse process of the atlas and the mastoid portion of the temporal bone, and is be- neath the several muscles which are inserted into the latter, as the sterno-mastoid, the splenius, and the trachelo-mastoid. It is covered, for some distance, by the insertion of the splenius capitis, and be- comes at length superficial at the posterior margin of this muscle. The occipital artery is distributed as follows: Shortly after its origin, it sends branches to the digastric muscle behind, to the upper part of the sterno-mastoid and to the lymphatic glands of the upper part of the neck. While enclosed by the mus- cles on the back of the neck, it also sends branches to them, and anastomoses thereby with the vertebral artery ; occasionally, one of these branches is of considerable magnitude, and has been found de- scending very low on the back, between the splenius and the com- plexus muscle. It also sends a small branch to the dura mater, through the mastoid foramen generally, but sometimes through the posterior foramen lacerum. When the stylo-mastoid artery is wanting, it also detaches a branch through the stylo-mastoid foramen to the internal parts of the ear. The occipital artery, having become superficial at the internal margin of the splenius on the occiput, ascends on the latter bone towards the vertex in a tortuous manner, sending off, on each side, CAROTIDS, AND THEIR BRANCHES. 239 many small ramifications. It ends by anastomosing with the pos- terior temporal artery. The Posterior Auricular Artery (Art. Auricular is Posterior ) arises a little above the last, at the lower edge of the parotid gland, from the external carotid, and is one of its smallest branches. It ascends backwards enclosed by the parotid gland, and afterwards between the meatus auditorius externus and the mastoid bone: at the latter place, it sends a ramification to the internal side of the external ear; it then ascends and is distributed, by small branches, on the contiguous integuments of the side of the head. While still in- volved in the parotid gland, it sends some small ramifications through the meatus externus to its lining membrane and the mem- brana tympani. It then detaches a branch through the stylo-mastoid foramen, from which the whole artery is also named Sty lo-Mastoid ; but this branch, as stated, sometimes comes from the occipital. The stylo-mastoid passes along the aqueduct of Fallopius, detaching its arterioles to the tympanum and to the labyrinth. The External Carotid having given off these trunks, penetrates vertically through the inner margin of the parotid gland, and gives to it several small twigs. When it arrives on a line with the neck of the lower jaw, it divides into two large trunks; one of them, the Internal Maxillary, goes to the parts within the ramus of the low'er jaw ; the other, being smaller, is the Temporal Artery. The Temporal Artery ( Arteria Temporalis ) continues to ascend through the substance of the parotid, but becomes superficial in front of the meatus externus, in mounting over the root of the zygoma ; it is then distributed to the integuments on the side of the head. It frequently sends off one or two ramifications, of but little volume, to the masseter muscle. Just above its root, and while surrounded by the parotid, a branch of some importance, the Trans- verse Facial, ( Transversalis Faciei ,) leaves it, and crosses, horizon- tally, the masseter muscle, just below r the parotid duct, sometimes above it. This branch is distributed to the adjacent integuments and muscles, and terminates in front by anastomosing with the facial and the infra-orb itar artery. A little below the zygoma, the Middle Temporal artery [Art. Temp. Media) comes off from the Temporal, and ascending with the parent trunk, perforates the temporal fascia at the upper margin of 240 CIRCULATORY SYSTEM. the zygoma, and is distributed to the temporal muscle by many ramifications, which anastomose with the deep-seated temporal arte- ries. After this, some small twigs, called Auricular, go to the ex- ternal ear from the trunk of the temporal artery. The temporal artery, having ascended for an inch or so between the aponeurosis of the temporal muscle and the skin, it divides into an Anterior and a Posterior Branch. The former ascends towards the side of the os frontis, and is distributed in ramuscules to the orbi- cularis palpebrarum, the anterior belly of the occipito frontalis, and the integuments of the front of the cranium, anastomosing with the frontal artery and the temporal of the other side. The posterior branch is distributed on the integuments of the middle of the side of the cranium, anastomosing with the anterior branch, with its fellow' of the other side, and with the occipital artery. The Internal Maxillary Artery ( Arteria Maxillaris Interna) winds round the neck of the lower jaw, and, passing between the ptery- goid muscles, proceeds in a tortuous manner to the deepest points of the zygomatic fossa. The first part of its course is horizontally inwards ; it then ascends in front of the pterygoideus externus to the bottom of the temporal bone, or the spinous process of the sphe- noidal : it then passes forwards, within the temporal muscle, to the upper part of the pterygo-maxillary fossa. It sends off several branches, and commonly in the following order : — 1. The Arteria Tympanica, to the tympanum, through the glenoid fissure. 2. The Arteria Meningea Parva, to the dura mater, through the foramen ovale. It is most frequently a branch of. the next. 3. The Arteria Meningea Magna, or Media, to the dura mater, through the foramen spinale. This branch having entered the cra- nium, is distributed upon the dura mater in the manner marked off by the furrows upon the internal face of the temporal, the parietal, and the frontal bones. One of its branches enters the aqueduct of Fallopius, through the Vidian Foramen, and is distributed upon the internal parts of the organ of hearing, anastomosing with the stylo- mastoid artery. CAROTIDS, AND THEIR BRANCHES. 241 4. The Arteria Maxillaris, or Dentalis Inferior, descends along the internal face of the ramus of the lower jaw, and having sent off some ramifications of small size to the contiguous muscles and the lining membrane of the mouth, it enters the posterior mental foramen with the inferior dental nerve. Going along the canal in the sub- stance of the lower jaw, it detaches successively from its superior margin ramifications to the teeth. At the anterior mental foramen a trunk is sent forward as far as the symphysis, which supplies in its course the canine and incisor teeth ; the remainder of the inferior maxillary artery comes out at the foramen, and supplies the chin, anastomosing with the facial artery. 5. The Arteriae Teraporales Profundae are two in number. The first of them, called Posterior, arises next to the inferior maxillary. It is concealed between the external pterygoid and the temporal muscle for some distance ; it then ascends in the posterior part of the temporal fossa, beneath the temporal muscle, and is minutely distri- buted upon it. The Anterior deep temporal artery is separated from the posterior, in its origin from the external maxillary, by the ptery- goid and the buccal arteries. It arises near the pterygo-maxillary fossa; and, ascending between the temporal muscle and the fore part of the corresponding fossa, it is minutely distributed upon the former, -anastomosing with the posterior deep, and with the middle temporal artery. 6. The Arteriae Pterygoideas arise after the posterior deep tem- poral. They vary considerably in regard to number, size, and origin, and are distributed upon the pterygoid muscles, as their name implies. One of their branches, which is sometimes an independent trunk from the internal maxillary, goes between the posterior margin of the tem- poral muscle and of the neck of the lower jaw, in front of the latter, to be distributed upon the internal face of the masseter muscle. 7. The Arteria Buccalis, sometimes a branch of the internal maxillary, but frequently coming from one of its trunks, either the alveolar or the anterior temporal, passes along the external face of the upper jaw, and distributes its branches to the buccinator and zygomatic muscles, and to the lining membrane of the mouth. 8. The Arteria Maxillaris Superior, or Alveolaris, proceeds down- 242 CIRCULATORY SYSTEM. wards and forwards in winding round the tuber of the upper jaw bone. It first sends some ramifications through the bone to the roots of the great and small molar teeth, and to the lining membrane of the maxillary sinus ; it then passes forwards along the gums, near the buccinator, and gives ramifications to them and to the contiguous muscles. 9. The Arteria Infra-orbitalis comes from the internal maxillary, at the upper part of the pterygo-maxillary fossa ; it sends some in- considerable ramifications to the fat and the periosteum of the orbit, through the spheno-maxillary fissure. It then enters the infra-orbi- tary canal, and passes through it with the infra-orbitary nerve. On arriving near the anterior orifice of the canal, it detaches downwards a branch which goes to the canine and the incisor teeth, and to the lining membrane of the antrum. It then gets to the face below the origin of the levator labii superioris muscle, and is distributed upon the muscles in front of the upper maxilla, anastomosing with the facial and with the ophthalmic artery. 10. The Arteria Palatina Superior descends through the posterior palatine canal, and having reached the mouth, leaves some ramifica- tions with the soft palate : it then advances- between the bones and the lining membrane of the roof of the mouth, and disperses itself in several small twigs; one of which passes through the foramen in- cisivum into the nostril. 11. The Arteria Pharyngea Superior is sometimes a branch of the last, and is spent upon that portion of the pharynx bordering on the pterygoid processes. 12. The Arteria Spheno-Palatina is the terminating trunk of the internal maxillary : it enters the nose through the spheno-palatine foramen, and divides into two branches, which are minutely dis- tributed over the Schneiderian membrane. One of them descends along the septum narium ; the other along the external margin of the posterior naris, and divides into two principal ramuscules, one of which is dispersed along the middle turbinated, and the other along the inferior turbinated bone. SUBCLAVIAN, AND ITS BRANCHES, 243 SECT. m. — OF THE SUBCLAVIAN ARTERY, AND ITS BRANCHES.* The Subclavian Artery ( Arteria Subclavia) of the right side having arisen from the innominata, and that of the left from the aorta, they each go over the first rib of their respective sides, ad- hering closely to it, in the bottom of the interval between the sca- lenus anticus and medius muscle. The right subclavian is much shorter, and more superficial than the left, from its origin to the scaleni muscles. Near the latter they are each covered in front by the sternal end of the clavicle, by the sterno-hyoid and thyroid muscle, and by the subclavian vein of the corresponding side ; be- hind they are separated from the vertebral column by the longus colli muscle ; below them is the pleura, the left artery being in con- tact with it for its whole passage in the thorax; and on their internal side is the primitive carotid. The subclavian of the right side is crossed near the scalenus anticus by the par vagum ; the phrenic nerve also goes in front of it, but on the internal edge of the scalenus. The subclavian of the left side having a course almost vertical from its origin to the interval of the scaleni muscles, is nearly parallel with and behind the primitive carotid of that side ; the phrenic nerve has the same relative position with it as on the right side ; but the par vagum goes parallel with, and in front of the sub- Flavian artery, for some distance along the root of the latter. At the inner margin of the Scaleni Muscles the Subclavian gives off a cluster of trunks ; to wit, the Vertebral ; the Inferior Thyroid; the Superior Intercostal ; the Internal Mammary ; and the Posterior Cervical Artery. They sometimes arise distinctly, and after the order mentioned : but there is too great a diversity in subjects to establish any rule on these points. 1. The Vertebral Artery ( Arteria Vertebralis ) is the most volu- minous of the branches of the Subclavian. Immediately after its origin it ascends on the side of the spine, and enters the canal of the transverse processes of the neck at the sixth vertebra. Pursuing this course, it gets into the cavity of the cranium through the fora- men magnum occipitis, and is distributed to the brain in the manner mentioned in the description of that organ. * Anat. Atlas, Figs. 454 to 460 inclusive. 244 CIRCULATORY SYSTEM. While in the canal of the transverse processes, it sends off several branches to the heads of the contiguous muscles, and to the medulla spinalis of the neck. The vertebral artery, like some others, is spindle-shaped, its size augmenting as it recedes from its origin ; this imparts some advantage to the current of the blood. 2. The Inferior Thyroid Artery ( Arteria Thyroidea Inferior) arises from the upper face of the subclavian, and goes to the thyroid gland. It ascends at first on the internal margin of the scalenus medius muscle, and then turns suddenly inwards between the vertebrae and the great vessels of the neck. In this course several unimportant twigs are sent from it to the contiguous parts. Near its root it detaches the Anterior, or the Ascending Cervical Artery, which going up the neck is spent upon the heads of the muscles arising from the transverse processes, as the scaleni, the longus colli, and so on. The inferior thyroidal then gets to the thyroid gland, and is very minutely distributed to it, anastomosing with the . other arteries which supply the same organ. 3. The Superior Intercostal Artery, ( Arteria Intercostalis Superior,) arising from the under surface of the subclavian opposite the inferior thyroid, descends across the neck of the first rib, and divides into two branches, which supply the two upper intercostal spaces : each of them also sends backwards near the vertebra a small trunk to the muscles of the back. 4. The Internal Mammary Artery ( Arteria Mammaria Interna, Thoracica) descends at first along the internal margin of the scalenus anticus; having then got fairly into the cavity of the thorax, it con- tinues to descend across the posterior face of the costal cartilages, parallel with, and about nine lines from the outer edge of the sternum, between the triangularis slerni and the intercostal muscles. In this course, besides some distinct twigs to the anterior medi- astinum, it sends a branch ( Phrenica Superior) which accompanying the phrenic nerve between the pleura and the pericardium, reaches finally the diaphragm, and is spent upon it. At each intercostal space which it crosses, the internal mammary sends outwards a branch, which is spent upon the fore part of the intercostal muscles, SUBCLAVIAN, AND ITS BRANCHES. 245 and anastomoses with the corresponding intercostal artery: other branches also leave it at each space, which getting forwards near the sternum, are distributed upon the pectoralis major, and upon the contiguous muscles. The last of these branches, according to M. H. Cloquet, goes transversely across the ensiform cartilage, and, having anastomosed with its fellow, descends between the peritoneum and the linea alba to the suspensory ligament of the liver. On a level generally with the anterior extremity of the sixth rib, the internal mammary divides into two principal branches; the most exterior of which, descending along the cartilaginous margin of the thorax, is distributed in small twigs to the origin there of the dia- phragm and of the transverse muscle of the abdomen. The internal branch reaches the posterior face of the rectus abdominis muscle, and is dispersed upon it: some of its branches go as low as the umbilicus, to anastomose there with the epigastric artery. 5. The Posterior Cervical Artery ( Arteria Cervicalis Posterior , Transversa) is of a very unsettled origin, but comes most frequently, either from the subclavian itself, or from the inferior thyroid. It is but small in some subjects, owing to its place being supplied by branches from the adjoining arteries. It crosses horizontally the root of the neck on the outer face of the scaleni muscles above the subclavian artery. It gets under the anterior margin of the trapezius, and is there divided into two prin- cipal branches; the ascending one is spent upon the trapezius and the levator scapulae; the other descends along the base of the scapula, and is spent in ramifications upon the rhomboidei and the serratus major muscle. Several branches of minor size and import- ance are sent otf from the posterior cervical artery to the muscles on the back of the neck and thorax. The Subclavian Artery having sent off the preceding branches, then escapes from the thorax between the scaleni muscles, and gets to the arm-pit between the first rib and the subclavius muscle. The trunk of it is then continued downwards through the axilla, and at the inner side of the arm to the elbow joint. From the scaleni muscles to the elbow its relative position is as follows: When it first appears between the scaleni, it is bounded above and behind by the collected fasciculi of the axillary plexus of nerves. In front it is separated from the subclavian vein by the Vol. II. — 22 246 CIRCULATORY SYSTEM. insertion of the scalenus anticus. It is placed at the bottom of the depression between the sterno-mastoideus and the trapezius, being covered by the skin, the platysma myodes, and some loose cellular substance below the latter. It then descends between the first rib and the subclavius muscle; escaping from below the latter, it is covered in front by the outer margin of the pectoralis major until it reaches the lower part of the axilla; and in this course it has the following relation to other parts: it passes first under the insertion of the pectoralis minor, then under the shoulder joint, then along the internal face of the coraco-brachialis muscle; it has the axillary vein in front of it, and the axillary nerves plaited around it as far down as the coracoid process, when they begin to disperse. This artery in emerging from the axilla is placed upon the anterior face of the insertion of the latissimus dorsi: it then runs out the length of the coraco-brachialis, and is afterwards conducted along the inner margin of the biceps flexor cubiti and of its tendinous termination ; it lies upon the anterior face of the brachialis internus ; and goes beneath the aponeurosis coming from the tendon of the biceps at the bend of the arm. In the arm it is concealed only by the integu- ments and fascia, and is bordered internally by the brachial vein and the median nerve. This great trunk of the upper extremity loses the name of sub- clavian, to be called Axillary Artery, [Art. Axillaris,) from the sub- clavian muscle to the lower margin of the arm-pit : and from the latter place to the elbow-joint, it is named Brachial Artery, (Art. Brachialis .) It sends off many interesting branches to the thorax, to the shoulder, and to the arm ; and, finally, terminates a little be- low or at the elbow joint by bifurcating. Of the Branches of the Axillary Artery. 1. The Superior Scapular Artery (Art. Dorsalis Superior Scapula) varies considerably in its origin. Sometimes it is a branch of the subclavian, sometimes of the inferior thyroid, and it frequently comes from the upper part of the axillary ; so that it canno’t be re- ferred, with strict propriety, to any determined origin. When it comes from the axillary, it is very tortuous, and has to ascend to its destination, which removes it entirely from any interference with the course of the subclavian over the first rib, and over the upper head AXILLARY, AND ITS BRANCHES. 247 of the serratus major muscle. But in the other cases, it goes trans- versely backwards and outwards, somewhat below the posterior cer- vical, and along the posterior inferior margin of the clavicle, being covered by the sterno-mastoideus, the platysma myodes, and the trapezius; consequently, it is just in the way of the incisions which are made for reaching the subclavian artery, from above the clavicle. It reaches the superior costa of the scapula near the root of the coracoid process, and passing through the notch there, is distributed, by one large branch, upon the supra spinatus muscle ; and by another, which goes across the anterior margin of the spine of the scapula, to the infra-spinatus muscle. In its course, it sends off several small ramifications to contiguous parts. 2. The External Mammary Arteries (Art. Mammarice seu Tho- racica Externa) arise from the axillary, between the subclavius and the pectoralis minor muscle. There are four principal trunks, which go uniformly to certain parts, but vary considerably in their origin ; for sometimes the latter is distinct in the case of each artery, but frequently otherwise. Their distribution is as follows: a. The Thoracica Superior is distributed to the upper part of the pectoralis major muscle, and to the pectoralis minor. Some of its branches reach the mamma in the female, and anastomose with the internal mammary and with the intercostals. b. The Thoracica Longa descends along the posterior face of the pectoralis major, between it and the serratus magnus. It gives many branches to the lower part of the pectoralis major, to the integuments, and, in the female, to the mamma ; anastomosing likewise with the internal mammary and with the intercostals. c. The Thoracica Acromialis, immediately after its origin, makes for the fissure between the deltoid and the great pectoral muscle, and divides there into an ascending and a descending branch. The former reaches the clavicle, and is partly distributed superficially along it, partly to the contiguous muscles, and to the shoulder arti- culation. The other branch follows the cephalic vein along the in- terstice between the deltoides and pectoralis major, and is, finally, distributed to these muscles and to the integuments. d. The Thoracica Axillaris is irregular, both in regard to the number of its branches and to their origin. Instead of a distinct origin by one or more trunks from the axillary artery, the branches belonging to the name of thoracica axillaris, are sometimes derived 248 CIRCULATORY SYSTEM. from the other thoracic arteries. They are generally distributed only to the fat and the lymphatic glands in the axilla. They occasionally exist primitively as a large trunk, which runs on the scapular face of the serratus major the whole length of the scapula, and is distributed to the adjacent muscles, and to the fat and glands of the axilla. 3. The Scapular Artery ( Arteria Scapulans communis , Subscapu- laris ) arises from the axillary below the shoulder joint, at or near the anterior margin of the subscapularis muscle. Giving off some in- considerable branches to the lymphatic glands of the arm-pit, it descends along the anterior margin of the subscapularis, and is dis- tributed to it, to the latissimus dorsi, and to the teres major and minor muscles, A little below the neck of the scapula, it detaches a large trunk, the Dorsalis Inferior Scapulm, which winding around the inferior costa of the bone over the anterior margin of the subscapularis and the teres minor, reaches the fossa infra-spinata. This trunk then divides into two branches : one of which is distributed superficially between the scapular aponeurosis and the infra-spinatus, and the other more deeply near the dorsum of the bone : one of the ramus- cles of the latter ascends beneath the neck of the acromion to anas- tomose with the Dorsalis Superior Scapulae. 4. The Anterior Circumflex Artery {Art. Circumfiexa Anterior, Articularis Anterior) is about the size of a crow quill, and arises from the axillary just above the tendon of the teres major and of the latissimus dorsi. It adheres closely to, and surrounds the front of the neck of the os humeri, passing between it, the coraco-brachialis, and the short head of the biceps. It then divides into several branches, some of which go to the deltoides, and anastomose there with the posterior circumflex ; others go immediately to the articula- tion, and either terminate on it or ascend to the muscles on the dorsum of the scapula, where they anastomose with the scapular arteries. 5. The Posterior Circumflex Artery {Art. Circumfiexa Posterior) is much larger than the last, and arises from the axillary somewhat below it. It surrounds the posterior face of the neck of the os humeri, passing between it and the long head of the triceps muscle, below the insertion of the teres minor. Many of its ramifications go to the capsular ligament of the articulation and to the muscles BRACHIAL, AND ITS BRANCHES. 249 adhering to it. But this artery is principally intended for the deltoid muscle, to the internal face of which the most of its branches go. It anastomoses with the anterior circumflex, and with the scapular arteries. In some cases, the posterior eircumflex arises from the axillary, below instead of above, the tendinous insertion of the latissimus dorsi : when this happens, it commonly gives off the arteria profunda major of the arm, and afterwards ascends on the posterior face of the tendon to its appropriate destination. Of the Branches of the Brachial Artery. 1. The Profound Artery (Arteria Profunda Major Humeri , Spi- ralis,) arises from the brachial, a little below the tendinous insertion of the latissimus dorsi, and having passed downwards, for a short distance, it enters the interstice between the first and the third head of the triceps muscle, and winds spirally downwards around the os humeri in company with the radial nerve. On the outer side of the arm, it becomes superficial between the margins of the triceps and of the brachialis interims, and then directs its course between the latter and the supinator longus to the external condyle. In this course, the artery sends several branches to the triceps muscle, to which, indeed, it is principally destined. Near the ex- ternal condyle, it supplies the brachialis internus and the heads of the extensor muscles of the fore-arm, and anastomoses with the recurrent branch of the radial artery. 2. The Small Profound Artery (Art. Profunda Minor) comes from the brachial, tw r o or three inches below 3 * * * 7 the profunda major, but frequently it is only a branch of the latter, and is generally much smaller. It is distributed superficially on the internal face of the triceps at its lower part, and has its terminating branches reaching as far as the internal condyle. 3. The Nutritious Artery (Art. jYutri.tia) is the next in order from the brachial, and arises from it near the medullary foramen of the os humeri, through which it penetrates, and is distributed to the lining membrane of the bone. It is not larger than a knitting needle. 250 CIRCULATORY SYSTEM. 4. The Anastomotic Artery ( Jlrteria Anastomotica ) arises from the brachial below the last, and is larger than it. It lies upon the lower internal part of the brachialis internus muscle, and crosses the ridge leading to the internal condyle in order to reach the depression between the latter and the olecranon, where it anastomoses with the ulnar recurrent artery.. The preceding is a common arrangement of the branches pro- ceeding from the brachial artery, yet deviations from it are continu- ally met with, in a deficiency or in a redundancy of these collateral trunks, and in their mode of origin. An account of all the varieties which are observed here would be almost endless, as every subject has some peculiarity. Several small arteries are also sent from the brachial to the coraco-brachialis, the biceps, the brachialis internus, and to the triceps muscle. They, for the most part, are, simply, muscular branches, which are too small and irregular to deserve spe- cifying. A division of the brachial artery into two trunks, the Radial and the Ulnar, will be found in a majority of subjects in front of the brachialis internus muscle on a line with the elbow joint: sometimes it occurs nearer the root of the coronoid process. It is, however, by no means rare to see this bifurcation much above the elbow. Examples of it have been witnessed at every point between the latter and the arm-pit ; in such cases, the course of the radial artery down the fore-arm is generally much more superficial than usual, as it is placed immediately below the skin. Of the Radial Artery. The Radial Artery ( Arteria Radialis) is smaller than the ulnar, and extends from the elbow to the hand. In the upper half of the fore-arm it is placed at the bottom of the fissure between the supi- nator radii longus and the pronator teres muscle. Having crossed the insertion of the latter, it runs in front of the radius between the tendon of the supinator and of the flexor carpi radialis. Below the styloid process of the radius it runs between the outer end of the carpus and the extensor muscles of the thumb ; it then pene- trates to the palm of the hand between the root of the metacarpal RADIAL ARTERY. 251 bone of the thumb and of the fore-finger above the abductor indicis muscle. The following branches are sent from the Radial Artery. 1. The Recurrens Radialis arises at the neck of the radius. It winds, externally around the joint between the external condyle and the muscles coming from it, and anastomoses with the spiralis of the humeral artery, being distributed in many collateral branches, to the joint and to the contiguous muscles. 2. Several small and irregular muscular branches arise from the radial artery, in its progress to the wrist: they have no appropriate names. 3. The Superficialis Volae arises from the radial about the infe- rior margin of the pronator quadratus muscle. It passes superfi- cially over the process of the trapezium to the muscles of the ball of the thumb, and one of its terminating branches joins the arcus sublimis. Sometimes the superficialis voire is the principal branch of the radial. 4. The Dorsalis Carpi arises from the radial at the carpus, runs across the back of the latter below the extensor tendons, and de- taches the posterior interosseous arteries of the back of the hand. They anastomose w'ith branches from the ulnar and interosseous arte- ries of the fore-arm. 5. The Magna Pollicis, a terminating branch of the radial, comes from it in the palm of the hand just at the root of the metacarpal bone of the thumb. It runs beneath the abductor indicis, and at the head of the metacarpal bone divides into two branches which go respectively along the sides of the thumb to its extremity, where they anastomose and terminate. 6. The Radialis Indicis, arising at the same place with the latter, runs along the metacarpal bone of the fore finger, and along the radial side of the same finger to its extremity. 7. The Palmaris Profunda is the third terminating branch of the radial artery. It arises near the same place with the last two, crosses 252 CIRCULATORY SYSTEM. the hand between the metacarpal bones and the flexor tendons ; thus forming the Arcus Profundus, from which branches proceed to the interossei muscles ; and which ends on the ulnar side of the palm of the hand by a connexion with the Arcus Superficialis. Of the Ulnar Artery. The Ulnar Artery, ( Arteria Ulnaris ,) one of the forks of the brachial at the elbow, passes more in a line with it than the radial artery does. It goes, immediately after its origin, under several of the muscles of the internal condyle, to wit: the pronator teres, flexor radialis, flexor sublimis, and palmaris longus, and between the flexor sublimis, and profundus digitorum, being deeply seated ; getting from beneath the flexor sublimis, it afterwards runs parallel with the ulna, or nearly so, lying on the flexor profundus between the flexor ulnaris and the ulnar margin of the flexor sublimis, and concealed two-thirds of the way down the fore arm by the over- lapping of these muscles. At the thin part of the fore arm, com- monly called the wrist, it is superficial, and may be felt pulsating in the living body at the radial margin of the tendon of the flexor ulnaris. The ulnar artery, at the carpus, takes a very different course from the radial; for it passes over the anterior annular ligament of the carpus just at the radial side of the os pisiforme, to which it is held by a small ligamentous noose ; it then proceeds to the palm of the hand. Between the aponeurosis palmaris and the flexor tendons it forms that curve from the ulnar to the radial side of the hand called the Arcus Sublimis. This curve commonly begins a little beyond the anterior margin of the annular ligament, and presenting its con- vexity forwards, terminates about the middle of the ball of the thumb at its inner margin. The branches sent from the ulnar artery are as follow : 1. The Recurrens Ulnaris arises from the ulnar about the lower part of the tubercle of the radius, and, winding upwards, is distri- buted in small branches to the muscles of the internal condyle. One of its ramuscules goes between the internal condyle and the olecranon process to anastomose with the arteria anastomotica of the humeral. ULNAR ARTERY. 253 2. The Interossea arises from the ulnar, just below the other. It is a large trunk, and proceeds but a little distance when it divides into two principal branches, called anterior and posterior interosseal arteries. a. The Interossea Anterior is much the larger ; it runs in contact with the interosseous ligament to the upper margin of the pronator quadratus, giving off branches to the deep-seated muscles of the fore arm in its course. Under the pronator it perforates the interosseous ligament, and distributes branches to the back of the carpus and of the hand, which anastomose with branches of the radial and posterior interosseal. b. The Interossea Posterior is sometimes a separate trunk, arising from the ulnar just above the former. In either case it soon per- forates the interosseous ligament to get to the back of the fore arm. Here it sends backwards a Recurrent Branch ( Recurrens Interossea) to the back of the elbow, which anastomoses with the recurrens ulnaris and radialis. It then proceeds downwards, being deeply seated and distributed to the different muscles on the back of the fore arm. Some of its branches reach the wrist, and anastomose with the carpal arteries. 3. The ulnar artery, in its descent on the fore arm, sends off many small and irregular muscular branches, called by Professor Chaussier, Cubito-muscular : they do not require description. 4. The Dorsalis Manus leaves the ulnar at the lower end of the fore arm, and passes under the tendon of the flexor ulnaris to the back of the hand. It there meets ramuscules of the radial and inter- osseous, and conjointly they supply with very small branches the back of the wrist, of the metacarpus, and of the fingers. 5. As the Arcus Sublimis is about beginning, the ulnar artery sends superficial but small branches to the integuments of the palm ; and a little farther on, a considerable branch, which dives into the bottom of the palm, through the muscles of the little finger, and joins the ulnar extremity of the arcus profundus : this is the Cubitalis Manus Profunda of Haller. 6. The Arcus Sublimis then sends a branch to the ulnar side of 254 CIRCULATORY SYSTEM. the little finger. Afterwards in succession three digital branches are sent off, which, arriving at the interstices between the heads of the several metacarpal bones, each divides into two branches to supply the sides of the fingers which are opposite to each other ; one branch is called Digito-radial, the other Digito-ulnar, according to the side of the finger on which the artery may be placed. In this way the radial side of the little finger, both sides of the ring finger, both sides of the middle finger, and the ulnar side of the fore finger are sup- plied. The digital arteries, before they divide, receive each a small branch from the arcus profundus. The digito-radial, and the digito- ulnar arteries, pass along the sides of the fingers in front to their ex- tremities; at the joints and extremities, many anastomoses between the arteries of the two sides of the same finger occur. The arcus sublimis terminates on the radial side of the palm by a branch which joins the inner branch of the Arteria Magna Pollicis of the Radial. The most frequent distribution of the arteries of the hand is what has just been described : anatomists are, however, not all agreed on this point. It would probably be more just to say, that this occurs more frequently than any other single arrangement. The varieties, in fact, are so great, that before a hand is opened, it is not possible to know in what manner its arteries will be distributed. Sometimes the Radial Artery furnishes one half of the arcus sublimis, and the Ulnar the other half. On other occasions, the interosseous artery, or the superficialis volae, is continued as a large trunk over the liga- ment of the wrist, to join the arcus sublimis, and to complete the digital arteries. SECT. IV. — BRANCHES OF THE DESCENDING THORACIC AORTA.* The Aorta, in its course from the lower part of its curvature to the crura of the Diaphragm, gives off several branches to the viscera and to the parietes of the thorax. The Bronchial Arteries ( Arterice Bronchioles ) are the nutritious vessels of the lungs. There is commonly one for each lung, but *Anat. Atlas, Fig-. 461. DESCENDING AORTA. 255 sometimes two or more. The right arises frequently from the supe- rior aortic intercostal artery, instead of from the aorta, while the left comes from the latter : occasionally they have a common root. On either side they follow the course of the bronchus into the substance of the lung ; and are distributed along with it, by ramifi- cations which become successively finer and finer, and anastomose with the pulmonary artery; after the manner mentioned in the de- scription of the lungs. Before they enter the latter, they send some small ramifications to the posterior mediastinum, to the pericardium, and to the black bronchial glands. The (Esophageal Arteries ( Arteries (Esophageal) are generally five or six small twigs which come successively from the descending thoracic aorta. They ramify minutely in the substance of the oeso- phagus, communicating freely with each other : the lowest of them also anastomose around the cardia with the superior artery of the stomach. The Posterior Arteries of the Mediastinum, (Arterice Mediasti- nales Posteriores,) are numerous and small ; they come from the anterior face of the aorta, as well as from the branches last men- tioned; and are spent upon the posterior mediastinum, and upon its contents. The Intercostal Arteries ( Arterice Intercostales Inferior es, A or tic ce) of the aorta supply the ten lower intercostal spaces on each side, as the two upper ones are supplied by the subclavian artery. There is commonly an intercostal artery arising distinctly from the aorta for each space, but sometimes two of them arise from a common trunk. Those for the right side having to cross the spine behind the oeso- phagus and the vena azygos, are, of course, longer than such as be- long to the left. The upper ones on either side have to ascend, in order to reach their destination. Each artery joins the rib near its tubercle, and goes along the groove in its lower margin, between the external and the internal intercostal muscle, for two-thirds of the length of the rib. It then abandons the groove, and divides into several branches, which go to the intercostal muscles and contiguous parts, and anastomose in front with the internal mammary artery. As each intercostal artery passes the head of the rib, it sends a 256 CIRCULATORY SYSTEM. branch backwards; ( ramus dorsalis ,) between the transverse pro- cesses of the adjoining vertebrae, which penetrates to the posterior face of the trunk, and is distributed to the muscles and skin on the side of the spine. A ramification from this branch enters the inter- vertebral foramen, and is spent upon the medulla spinalis and its membranes. Each intercostal artery also gives off, about the middle of the rib, a branch, ( ramus costalis inferior ,) much smaller than the trunk. This branch advances along the upper margin of the rib below, and gives ramifications to its periosteum and to the adjacent intercostal muscles. The last intercostal artery is remarkable for its size. Its origin is concealed by the small muscle of the diaphragm, to which it gives some ramifications : it then passes, at the under margin of the last rib, behind the upper end of the quadratus lumborum muscle, where it divides into three branches; one of which goes transversely to the broad muscles of the abdomen; while the other two descend be- tween the oblique and transverse muscles towards the crest of the ilium, where they anastomose with the lumbar arteries, and with the circumflexa ilii. SECT. V. — OF THE BRANCHES OF THE ABDOMINAL AORTA.* The Phrenic Arteries ( Arterice Pkrenicce ) are two in number, one for the right and the other for the left side of the diaphragm. They arise singly, but sometimes by a common trunk, from the front of the aorta, immediately on the latter showing itself in the abdomen, between the crura of the diaphragm ; consequently, just below the crossing of the muscular fibres, which takes place between the foramen for the aorta and that for the oesophagus. The phrenic arteries ascend along the lesser muscle of the dia- phragm, and give some ramifications to it and to the capsulse re- nales. They then divide each into two leading trunks, which are distributed over the diaphragm, principally on its concave surface. Some small ramifications from them go to the liver and to the lower part of the oesophagus. The two phrenic arteries anastomose with each other : also, with * Anat. Atlas, Figs. 462 to 465, inclusive. BRANCHES OF THE ABDOMINAL AORTA. 257 the superior phrenics, coming from the internal mammary ; and with the intercostals. Sometimes one or both of them come from the cceliac artery, or its branches. The Cceliac Artery (Arteria Coeliaca) is the next branch of the abdominal aorta, and arises immediately below the phrenics, between the crura of the diaphragm, opposite the junction of the last dorsal with the first lumbar vertebra. It is a very large trunk, and goes off at right angles, being placed between the left lobe of the liver and the superior margin of the pancreas. When it is only half an inch long, it is split into three trunks, the Gastric, the Hepatic, and the Splenic; this division is the Tripus Halleri. The Gastric Artery ( Arteria Gastrica, Coronaria Ventriculi) is the smallest of the three trunks, and frequently arises from one of the others. It advances forwards and towards the cardiac orifice in order to reach the small curvature of the stomach, the course of which it pursues to the pylorus, between the two laminae of the smaller omentum. It gives off the following branches a. Ramifications to the oesophagus, some of which ascend along it into the posterior mediastinum, and anastomose there with the • similar branches coming from the aorta; others go transversely, so as to surround the cardia, reach the greater end of the stomach, and anastomose with the vasa brevia. b. The ramifications to the stomach are abundant, but of an in- determinate number, and arising along its lesser curvature, are dis- tributed in winding branches to the anterior and the posterior sur- faces of this viscus, between its membranes. c. Not unfrequently the artery which supplies the left lobe of the liver is a branch from the gastric, in which case the latter is much larger than usual. 2. The Hepatic Artery ( Arteria Hepatica) is generally consider- ably larger than the gastric, and inclines towards the right side, in order to reach the liver, which it does through the capsule of Glisson. It sends off the following branches : — a. The Right Gastric or Gastro-Epiploic Artery ( Arteria Gas- trica Dextra) comes from it near the pylorus, and descending be- tween the duodenum and pancreas, reaches the greater curvature of the stomach, to the right half of which, and to the correspond- Vol. II.— 23 •258 CIRCULATORY SYSTEM. ing part of the great omentum, it is distributed. In the early part of its course, the right gastric detaches some small ramifications to the pylorus (arteries pylorica ;) also, to the duodenum and to the pancreas (art. pancreatico-duodenales.) The latter communicate, by very free anastomoses, with the superior mesenteric artery. After having sent off this branch, the hepatic artery advances to the transverse fissure of the liver, in front of and to the left of the vena portarum. It then divides into a right and a left branch. The former sends off a ramification to the gall-bladder, (Art. Cys- tica, ) which first reaches its neck, and is distributed, by many arte- rioles, upon the parietes of this reservoir ; the right branch then penetrates deeply into the transverse fissure, and is distributed by many ramifications, throughout the right lobe of the liver. The left branch of the hepatic artery is distributed, in the same manner, throughout the left lobe of the liver. 3. The Splenic Artery ( Arteria Splenica ) is larger in the adult than either of the other two branches of the coeliac, and goes to the spleen along the superior margin of the pancreas, performing, in this course, several considerable flexuosities. It gives off the following branches : — a. The Pancreatic Arteries, (Art. Pancreatica Medice et Sinistra) come successively from its inferior margin, as it goes along the pan- creas. Their number and size are variable, but commonly they are not bigger than a knitting needle ; they penetrate perpendicularly into the pancreas, and then subdivide minutely in furnishing its structure. b. The Left Gastric Artery (Art. Gastrica Sinistra , Gastro-epi- ploica Sinistra) comes from the left extremity of the splenic, and is about the same size with the right gastric artery, but sometimes larger. It attaches itself to the left' extremity of the stomach, and goes along the left half of its greater curvature, terminating by an anastomosis with the right gastric artery. In this course, it detaches ramifications to the front and to the back of the stomach, and to the omentum majus. c. The Short Vessels (Vasa Brevia, Art. Gastrica. Breves ) come from the splenic, immediately before it enters the spleen, and after it has subdivided for that purpose. They are five or six in number, and are distributed upon the greater extremity of the stomach, be- tween the cardia and the left gastric artery. The anastomoses BRANCHES OF THE ABDOMINAL AORTA. 259 between the several arteries of the stomach are so free, that a fine injection pushed into one, readily finds its way into all the others. The splenic artery, when it gets to the left end of the pancreas, is divided into a cluster of branches, and in that condition enters the fissure of the spleen, throughout the interior of which it is divided into innumerable ramifications. The Superior Mesenteric Artery (Arteria Mesenterica Superior ) arises from the aorta, while the latter is still engaged, between the crura of the diaphragm. It is about the same size as the cceliac, and comes off half an inch below it. It is distributed to all the small intestines and to the right side of the large one after the following manner: it first passes behind the pancreas, and then in front of the duodenum, to reach the root of the mesentery, between the two la- minae of which it divides and subdivides into several series of arches, one after another : they become successively smaller and more nu- merous till they reach the margin of the intestine, where they cease by sending a great many small parallel branches. The trunk of the superior mesenteric artery, in descending be- tween the lamina of the mesentery, describes a considerable curva- ture, the convexity of which is to the left side and downwards, while its concavity is in a contrary direction. It is from the convexity of this trunk, that from fifteen to twenty large branches are sent ofif suc- cessively to form the roots of the first row of arterial arches. These branches are shorter, and generally somewhat smaller, the lower down they arise , and their origins very closely succeed each other. Upon the first row of arches or anastomoses is formed a second more numerous and small, and upon the second row is formed a third still more numerous and small, from which proceed the intestinal branches. Besides the preceding branches, the superior mesenteric artery sends off the following : Near its root several small ramifications arise, which go to the duodenum and to the pancreas, and anastomose there with the other arteries supplying the same organs. From about the middle of the concavity of the superior mesen- teric artery, arise the three Colic arteries called Ileo-colica, Colica Dextra, and Colica Media : the first supplies a cluster of branches to the lower part of the ileum and to the head of the colon, anasto- mosing on the left with the last of the small intestinal arteries and on the right with the colica dextra: the Colica Dextra is smaller 260 CIRCULATORY SYSTEM. than either of the other two branches, and going between the laminae of the mesocolon, supplies the ascending portion of the colon by dividing into two principal branches, one of which anastomoses with the ileo-colic artery, and the other with the colica media : the Colica Media, situated between the laminae of the transverse meso- colon, and arising higher up than the colica dextra, advances for- wards and divides into two principal trunks ; one of which supplies that part of the colon in the right hypochondriac region, and the other the remainder of its transverse portion, forming an anasto- mosis with the colica superior of the inferior mesenteric artery. The arteries which supply the colon differ from those supplying the small intestines, in forming but one row of arches ; which, in fact, are produced by the anastomoses spoken of, and have, therefore, ex- tremely large meshes. From the convexity of these arches, many parallel branches run out to supply the colon, and are very minutely distributed to it. The Capsular Arteries, the Emulgents, and the Spermatics, arise from the aorta, between the superior and the inferior mesenteric. But they will be described after the inferior mesenteric, so as to keep together the account of the arteries of the intestines. The Inferior Mesenteric Artery, ( Art . Mesenterica Inferior) gene- rally arises about one inch above the division of the aorta into the two primitive iliacs, and is much smaller than the superior Mesen- teric. It inclines downwards to the left side, and gets between the laminm of the mesocolon ; it then divides into three branches, called the Left Colic Arteries, from their distribution to the left side of the colon. From their relative situation to each other, they are distin- guished into the Superior, the Middle, and the Inferior; sometimes, however, there are but two of these trunks. The Superior Colic (Art. Colica Sinistra Superior) goes horizon- tally towards the colon in the left lumbar region; having got near the intestine it divides into two branches, one of which ascends to the transverse colon to form the anastomosis with the Colica Media of the upper mesenteric, while the other descends to unite with the colica media sinistra. The Middle Colic Artery (Art. Colica Sin- istra Media ) is sometimes a branch of the superior, and is occasion- ally wanting; it goes towards the upper part of the sigmoid flexure BRANCHES OF THE ABDOMINAL AORTA. 261 of the colon, and then bifurcates: one branch ascends to form by anastomosis an arch with the superior colic, while the other branch descends to join the lower colic artery. The Inferior Colic Artery {Art. Colica Sinistra Inferior ) goes towards the middle of the sigmoid flexure of the colon, and there, like the preceding, divides into two branches; one anastomoses with the artery above, while the other joins with the arteries which go to the rectum from the inferior mesenteric. The Superior Hemorrhoidal Artery {Art^Hcemorrhoidea Superior , Interna ,) is the lowest and the last branc^HKe inferior mesenteric. It descends between the laminae of the mes^Tc^n, and is resolved into two symmetrical trunks, which radiate bj^jmviding and sub- dividing on the side of the rectum, and are dispersed in very fine and numerous branches throughout its substance. It anastomoses with the middle and the inferior haemorrhoidal arteries, also with the lateral sacral. The Capsular Arteries {Art. Capsulares ) arise frequently from the aorta just below the superior mesenteric; but quite as often, if not more so, from the emulgents. They are not larger than a crow’s quill, and vary from one to three on either side; generally how r ever not exceeding one: and when they do, they are proportionably small. Passing horizontally outwards, they divide into several small ramifications, which terminate in the capsulce renales. Some of their branches go to the lesser muscle of the diaphragm. The Em ul gent Arteries {Art. Emulgentes , Renales ,) are two in number, one for each kidney, but sometimes more. They are large but short; arise from the side of the aorta immediately below the superior mesenteric, and pass outwardly in a horizontal direction. The right one is longer than the left, somewhat lower down, and passes behind the ascending cava. They are both, in their course, from the aorta to the kidney, covered in front by the emulgent vein, and have to pass through a mass of adipose matter. The emulgent sends off some fine ramifications to the adipose matter, which surrounds it, and before it reaches the fissure of the kidney divides into three or four branches, preparatory to its intro- duction into this gland, upon the structure of which it is ultimately distributed by very fine branches. 23 s5 ■262 CIRCULATORY SYSTEM. The Spermatic Arteries (Arteria Spermatic # , Seminales,) arise from the aorta somewhat below the emulgents, but in some cases from the latter themselves. They are two in number, one on each side, and are about the size of a crow quill in the male subject, but smaller in the female. One comes off generally higher up than the other; they then descend on the sides of the vertebral column before the psoae muscles, and cross in front of the ureters, being in all this course behind the peritoneum. They are tortuous, and shortly after their origin begin to adhere to the spermatic veins, which adhesion is continued to the testicle. The branches that the spermatic artery sends off in the abdomen are inconsiderable, consisting in very fine twigs to the adjacent adipose matter, to the lymphatic glands, to the ureter, and to the peritoneum. In the male subject it passes with the vas deferens, through the abdominal canal, and reaching the testicle divides into branches which supply the body of this gland and the epididymis. In descending from the external ring to the testis, some small rami- fications, to the adjacent parts, leave it. In the female, the sper- matic artery does not leave the cavity of the abdomen, but, de- scending into the pelvis, gets between the laminae of the broad ligament to the ovarium, and is spent principally upon the latter. Some of its branches go to the Fallopian Tube, to the Round Liga- ment of the uterus, and to the sides of the latter, where they anas- tomose with the uterine arteries.* The Lumbar Arteries ( Arterice Lumbares ) are commonly five in number on either side, but seldom less than three, and in their course outwards, correspond with the intercostal arteries. They are much larger than the latter. They arise in pairs from the posterior external face of the aorta, at a point corresponding with the middle of the bodies of the four upper lumbar vertebrae, and pass outwards be- tween the fasciculi of the psoas magnus muscle, to which, to the quadratus lumborurn, and the bodies of the vertebrae, they distribute several branches. Sometimes each pair arises by a common trunk from the posterior face of the aorta. As the latter terminates at the fourth lumbar vertebra, the fifth lumbar artery is a branch from the fourth in most instances. * The spermatic artery is spindle-shaped, the smallest end being' the origin ; this favours the flow of blood in it, which would otherwise suffer from so much friction, BRANCHES OF THE ABDOMINAL AORTA. 263 At the base of the transverse process each artery divides into two branches, a posterior or dorsal one, and an anterior or lumbar. The dorsal branch, which is smaller than the other, detaches a ra- mification through the intervertebral foramen to the lower part of the medulla spinalis and to the cauda equina: it then gets to the back, where it is spent upon the muscles near the spine. The anterior lumbar branch advances between the broad muscles of the abdomen to which it is distributed ; and runs forwards far enough to anasto- mose with the epigastric artery. The first lumbar artery is the smaller, and sometimes comes from the last intercostal : it goes a little below the inferior margin of the last rib, and then descends almost vertically between the peritoneum and the transversalis abdominis muscle. The lower lumbar arteries anastomose with the circumflexa ilii, and with the superficial branches of the gluteal. The Middle Sacral Artery (Arteria Sacra Media ) is generally not so large as a lumbar; it arises from the centre of the bifurcation of the aorta into the two primitive iliacs, or else a line or two above it, behind. It descends, in front of the middle line of the fifth lumbar vertebra and of the sacrum, to the coccyx adhering to the surface of these bones, and performing some flexuosities. It sometimes happens that the last pair of lumbar arteries comes from it, or at least one, according to Meckel, more commonly the left: in which case the sacral is of unusual size. The sacral after- wards sends off, to the right and left, a pair of branches for each pair of sacral foramina. They run across the sacrum, send branches to it, anastomose with the lateral sacral arteries, and then penetrate to the cauda equina. The middle sacral artery is lost at the inferior end of the coccyx, in the fat and cellular tissue of the part. SECT. VI. — OF THE PRIMITIVE ILIAC ARTERIES, AND THEIR BRANCHES. * The Primitive Iliac Arteries, [Art. Iliacce Primitivcc communes ,) one on each side, are, as mentioned, the terminating trunks of the abdominal aorta. They extend from the lower part of the fourth * Anat. Atlas, Fig. 465. 264 CIRCULATORY SYSTEM. lumbar vertebra to the sacro-iliac junction, or near it, where they divide into two trunks, the Internal and the External Iliac. This division however not unfrequently occurs at the inferior lateral edge of the fifth lumbar vertebra, near the base of the sacrum. The primitive iliac is bounded on the outer side by the psoas magnus muscle, and behind by the primitive iliac vein ; it is crossed at its lower part by the ureter. No branches deserving of especial notice are sent from it before it bifurcates; such as exist are very small, and go simply to the parts immediately contiguous. The right artery crosses in front of the root of the left iliac vein. SECT. VII. — OF THE INTERNAL ILIAC, OR THE HYPOGASTRIC ARTERY.* The Internal Iliac Artery (Art. lliaca Interna , Hypogastrica ) descends from its origin near the front upper part of the sacro-iliac junction, to the lower part of the same articulation. In this descent, it is bounded behind by the sacral plexus of nerves, and gives off several arterial trunks ; but the manner by which the last is accom- plished is much varied in different subjects. For the most part, it is an inch or more long before any important branches leave it ; it is then frequently divided into two principal trunks, an anterior and a posterior, from which proceed the several branches that supply the internal and the external parts of the pelvis. The rule of ori- gin of the secondary trunks from these two principal ones,' even when the latter exist, is not fixed ; for sometimes they arise from one, sometimes from the other, and then again from the trunk of the hypogastric itself. The Ilio-Lumbar Artery (Art. Ilio Lumbaris ) is commonly the first branch of the hypogastric, or of its posterior trunk. It ascends outwards and backwards behind the psoas magnus muscle, and there divides into two branches, a superior and an inferior. The former continues to ascend between the psoas magnus and the iliacus interims muscle, to which, and to the quadratus lumborum, it dis- tributes branches: it also sends ramifications into the spinal cavity, and anastomoses with the lower lumbar arteries ; sometimes it sup- * Anat. Atlas, Figs. 469 to 472, inclusive. INTERNAL ILIAC ARTEKY, AND ITS BRANCHES, 265 plies the place of the last lumbar entirely. The inferior branch going outwardly, is divided into two orders of ramifications which supply the iliacus internus muscle, on its surface and more deeply ; also the os ilium by a ramuscule which penetrates the nutritious fora- men of the latter. The inferior branch anastomoses with the cir- cumflexa ilii of the external iliac. The Lateral Sacral Arteries ( Arteries Sacra Laterales ) arise next, either from the hypogastric or from its posterior trunk : their number is commonly equal to that of the foramina on the side of the sacrum in front, though they may come from only one or two roots. They cross in front of the sacrum, and divide into branches, some of which anastomose with the middle sacral artery, while others enter the foramina of the sacrum, to be spent on the lower part of the cauda equina. The Obturator Artery ( Arteria Obturatoria ) comes commonly from the hypogastric or from one of its principal trunks ; in some cases it arises from the epigastric or from the external iliac, near Poupart’s ligament. In the first cases it passes forwards parallel with the brim of the pelvis, and in the latter cases it descends behind the superior ramus of the pubes. Whatever may be the condition of its origin, it gets from the pelvis through the upper part of the thyroid foramen over the superior margin of the obturator internus muscle, having previously sent off some inconsiderable ramifications to the periosteum and the contiguous muscles within the pelvis. It emerges from the pelvis on the upper margin of the obturator externus muscle, and then divides into two principal trunks. The posterior descends along the external margin of the obturator ex- ternus muscle, to which it gives ramifications ; it likewise sends some branches to the heads of the muscles coming from the tuber of the ischium, and thereby anastomoses with the sciatic artery : other branches are spent upon the hip joint, one of which gets into the cavity of the latter through the notch at the lower part of the acetabulum, and is spent upon the adipose matter in its bottom. The anterior branch goes to the heads of the adductor muscles, to the pectineus, to the obturator externus, and to the integuments of the upper internal part of the thigh. Near its origin this branch sends a ramification along the internal margin of the thyroid fora- 266 CIRCULATORY SYSTEM. men to anastomose Avith the posterior branch, so that the foramen, is surrounded by an arterial circle. The Middle Haemorrhoidal Artery [Art. Hcemorrhoidea Media) varies in its origin, being sometimes from the hypogastric itself and, on other occasions, from one of its branches, as the gluteal, ischiatic, &c. It descends on the fore part of the rectum, opposite the loAver fundus of the bladder in the male, and is distributed by branches to the rectum, to the vesicula seminalis, and to the pros- tate gland. In the female it dispenses branches to the vagina. It is called middle, from its position betAveen the upper and the loAver haemorrhoidal arteries. In both sexes, the branches which it sends to other parts besides the rectum, frequently arise from other arteries, and in a man- ner which causes them to have distinct appellations, as vaginal, &c. The Vesical Arteries [Arteries Vesicates) consist in several rami- fications, coming from Avhat was the umbilical artery of the foetus, but which, in the adult, with the exception of a short space near its origin, is converted into a ligamentous chord. These branches ramify upon the parietes of the bladder ; one of them more volumi- nous than any other, and called, by M. Chaussier, A r esico-prostatic, gains the lower fundus of the bladder ; sends branches to it, to the prostate, to the vesicula seminalis, and to the commencement of the urethra. The Uterine Artery [Arteria Uterina ) arises from the hypogastric, or one of its branches, near the vesical, sometimes before, and on other occasions subsequent to them. Being peculiar to the female sex, its size varies according to the individual being in a state of pregnancy or not : in the latter stages of gestation it is as large as any other branch of the hypogastric. It goes inwards toAvards the superior part of the vagina, to which it gives some ramifications ; it then ascends between the laminae of the broad ligament, in a tortuous manner along the side of the uterus, and divides into many branches which are distributed through the tissue of this organ. It anastomoses with the corresponding arteries of the other side, and with the branches of the spermatic artery which go to the Fallopian tube and to the ovarium. Besides the preceding, the Hypogastric, or Internal Iliac artery INTERNAL ILIAC ARTERY, AND ITS BRANCHES. 267 sends off two large branches, the Gluteal and the Ischiatic, which terminate it. In many subjects they are the direct continuation of the two primitive trunks, into which the hypogastric is frequently originally divided. The Gluteal Artery, ( Arteria Glutea ,) shortly after its origin, issues from the pelvis above the pyriformis muscle, at the upper part of the ischiatic foramen, where it adheres closely to the edge of the bone. When it first gets to the dorsum of the ilium, it is covered by the gluteus magnus muscle, and lies at the posterior margin of the gluteus minimus, precisely under a line drawn from the posterior superior spinous process to the top of the trochanter major. It almost immediately afterwards divides into two principal trunks. One of these trunks, the more superficial, advances between the gluteus medius and the magnus, and distributes branches to them ; also, to the posterior margin of the magnus, where it comes from the posterior sacro-sciatic ligament. The more deeply-seated trunk goes forwards between the gluteus medius and minimus, and sub- divides into three orders of branches for their supply. One set follows the superior margin of the gluteus minimus towards the anterior superior spinous process ; another set passes nearer the middle of the gluteus minimus ; and the third set still lower down upon the dorsum of the ilium, above the acetabulum ; some of the ramifications go to the capsular ligament of the joint, where they anastomose with branches from the femoral artery. The Ischiatic Artery ( Arteria Ischiadica ) is somewhat smaller than the gluteal, but looks rather more like the continuation of the hypo- gastric. It descends between the rectum and the pyriformis muscle, and issues under the lower margin of the latter, out of the pelvis, being there placed in front of the sciatic nerve. It goes downwards on the back of the thigh, between the trochanter major and the tuberosity of the ischium, being at the internal edge of the sciatic nerve, and on the posterior face of the small rotator muscles of the thigh. It sends off in the pelvis the internal Pudic Artery, and also some inconstant branches, of small size, to the viscera within the pelvis; when it has emerged from the latter, it detaches some con- siderable branches to the origin and to the inferior margin of the gluteus magnus muscle, and to the small rotator muscles. The branch which may be considered as the continued trunk of the •268 CIRCULATORY SYSTEM. ischiatic, descending on the posterior face of the thigh, along with the sciatic nerve, under the hamstring muscles, is lost in ramifica- tions to them, and by anastomoses with the perforating arteries. The Internal Pudic Artery,* ( Arteria Pudica Interna ,) though a branch of the ischiatic, is only in a slight degree smaller. It arises a little above the spinous process of the ischium, in the pelvis, in front of the sciatic plexus, and getting from the pelvis between the anterior sacro-sciatic ligament and the inferior margin of the pyri- formis muscle, it passes over the posterior face of the anterior sacro- sciatic ligament, at the spinous process of the ischium. It imme- diately afterwards returns into the cavity of the pelvis, between the two sacro-sciatic ligaments, at the place where the obturator internus muscle winds over the ischium ; it then goes along the internal face of the latter bone and of its ascending ramus, at the inferior margin of the obturator internus muscle ; and continues on the internal face of the ramus of the pubes, between the two laminae of the triangular ligament, above the crus of the penis to the symphysis of the pubes. In this course the Internal Pudic Artery detaches several impor- tant branches, in the following order : — a. A ramification along the inferior margin of the pyriformis, to tills muscle and to the parts on the posterior face of the neck of the os femoris, where it anastomoses with the other arteries of this re- gion. b. The Lower Haemorrhoidal Artery [Art. Ilcemorrhoidea Inferior , Externa ) to the inferior part of the rectum, and to the external sphincter ani muscle. This artery arises after the internal pudic has returned within the pelvis, and consists sometimes in several branches. c. The Perineal Artery {Art. Perinea , Transversa Perinei ) has its root near the origin of the transversus perinei muscle, and ad- vancing obliquely forwards is distributed in several ramifications to the muscles and integuments of the perineum, and to the posterior part of the scrotum. It is unavoidably cut in the lateral operation for the stone. In the female it goes to the sphincter vaginae and to the labium externum. d. When the internal pudic has got beyond the transversus peri- nei muscle near the beginning of the crus penis, it detaches to the * Anat. Atlas. Fig. 467. EXTERNAL ILIAC ARTERY, AND ITS BRANCHES. 269 bulb of the urethra, along the posterior margin of the triangular liga- ment, a branch which penetrates to the corpus spongiosum, and is minutely distributed upon it, some of its ramifications reaching to the corpus cavernosum. This branch is called by M. Chaussier, Urethro-bulbar, and instead of being always distinct, it on some oc- casions comes from the Perineal. e. At the under part of the symphysis pubis, between it and the back of the penis, the internal pudic sends forwards, on the dorsum of the penis, a superficial branch, ( Ramus Superficialis Dorsi Penis.) It advances to the end of the penis, under the skin, being parallel with its fellow of the other side, and near to it : sometimes the two unite after a short course. They are dispersed in branches to the integuments, and to the elastic ligament of the penis. f The Cavernous Artery of the Penis (Art. Cavernosa Profunda Penis) may be considered as the terminating trunk of the internal pudic. It penetrates the corpus cavernosum, beneath the symphy- sis of the pubes, and quickly divides into many ramifications. The latter advance, and continue to subdivide upon the cells of the corpus cavernosum, to which they are principally distributed : some of them reach the corpus spongiosum urethras, and others anastomose with the corresponding arteries of the other side. SECT. VIII. — OF THE EXTERNAL ILIAC ARTERY, AND ITS BRANCHES.* The External Iliac Artery (Arteria lliaca Externa) extends from the bifurcation of the primitive iliac to Poupart’s ligament, where it is continued to the lower extremity under the name of the femoral artery. It looks like the continuation of the .primitive iliac, and de- scends at the superior strait of the pelvis along the internal margin of the psoas magnus muscle. In the early part of its course, it is anterior to the external iliac vein ; it then, as it approaches Poupart’s ligament, gets to its outer margin. It is covered by the peritoneum in front. Where it passes beneath Poupart’s ligament to the thigh, it is about half way between the anterior superior spinous process of the ilium and the symphysis pubis, having the vein at its pubic margin and the anterior crural nerve, half an inch from its iliac * Anat. Atlas, Figs. 466, 468. Vol. II.— 24 270 CIRCULATORY SYSTEM. margin. No branches of consequence arise before it reaches the crural arch ; it then sends of two, the Epigastric and the Circumflex Iliac Artery. The Epigastric Artery ( Jlrteria Epigastrica ) arises somewhat above the crural arch, at the line where the peritoneum is reflected |rom the fascia transversalis upon the iliac fascia. It at first passes horizontally inwards, then rises obliquely upwards and inwards, be- hind the spermatic chord, at the pubic margin of the internal abdo- minal ring. Afterwards it reaches the external margin of the rectus abdominis muscle, two or three inches above the pubes: ascending along it for a short distance, it then passes to its posterior face, and continues ascending above the umbilicus; where being divided into several branches, it terminates by anastomosing with the lower ra- mifications of the internal mammary artery. This artery is almost entirely spent upon the anterior parietes of the abdomen, in ramifications, which anastomose with the last in- tercostals and with the lumbar arteries. One of its small twigs, ■called the External Spermatic artery, following the course of the spermatic chord, or of the round ligament, is distributed upon the cremaster, the tunica vaginalis, and the scrotum of the male, and upon the inons veneris of the female. In some cases the epigastric gives off the obturator artery as stated. The Circumflex Iliac Artery ( jlrteria, Circumflexa liii) is of the same size with the epigastric, and comes from the external iliac, sometimes on a level with it, and on other occasions lower down, even below the crural arch. It ascends outwardly towards the an- terior superior spinous process of the ilium, along the posterior mar- gin of the crural arch, and following afterwards the direction of the crista of the ilium, it anastomoses with the corresponding branch of the ilio-lumbar artery. The following branches come from it. In the early part of its course some important twigs are sent to the adjacent muscles, as the sartorius, iliacus interims and so on. At the anterior superior spinous process, it divides into two branches; the smaller ascends between the internal oblique and the transversalis muscle, and is distributed upon them ; the other branch which is the continuation of the main trunk along the crista of the ilium at the margin of the iliacus internus muscle, sends ramifications to the latter, and also FEMORAL ARTERY, AND ITS BRANCHES. 271 to the posterior part of the broad muscles of the abdomen, where it anastomoses with the other arteries of this region. Of the Femoral Artery * The Femoral Artery ( Arteria Femoralis, Cruralis ,) the continua- tion of the external iliac, extends from the crural arch or Poupart’s ligament, to a perforation for its passage through the adductor mag- nus muscle, and which is commonly one-third of the whole length of the os femoris, above the knee joint. This great trunk, imme- diately below Poupart’s ligament is very superficial, and may be felt pulsating where it passes over the pubes. It is there covered only by the common integuments, and the fascia femoris, which is thin; it is bounded internally by the femoral vein, externally by the crural nerve ; is half-way between the anterior superior spinous pro- cess and the symphysis of the pubes, and lies upon the internal face of the psoas magnus over the interstice between it and the pectineus. In the upper third of its course the femoral artery is at the inner edge of the rectus femoris, and at a short distance from it ; it then inclines inwards, and occupies the angle formed by the ad- hesion of the vastus internus to the adductor longus. The sartorius, at first, is remote at its outside, but this muscle, inclining inwards in its descent gets to the exterior margin of the artery, and afterwards covers it completely for the remainder of its course. The femoral .artery is in front of the femoral vein when it has descended three or four inches below the crural arch; behind the two is the arteria profunda. When the femoral artery and vein reach the angle formed by the vastus internus and the adductor longus, they are covered by a strong interlacement of tendinous fibres from these muscles. The femoral artery sends off these branches : 1. The Superficial Artery of the Abdomen (Art. ad Cutem Ab- dominis) is small, and arises at the lower margin of Poupart’s liga- ment: it goes upwards towards the umbilicus, beneath the fascia superficialis abdominis, and is distributed to the integuments of this region. One of its ramifications goes to the inguinal glands. * Anat. Atlas, Figs. 466, 469. 272 CIRCULATORY SYSTEM. 2. The External Pudic Arteries (Art. Pudenda Externa ) come from the femoral at the same point-, and are two or three in number ; they are of small size. One of them inclines inwards along the groin, between the skin and the fascia femoris, and is distributed to the integuments of the pubes, to those of the penis, and to the scrotum, or to the labium externum of the female. The second, and the third when it exists, are rather lower down, and are dispersed upon much the same region by branches to the integuments. The lymphatic glands of the groin also derive their supply of blood from these several external pudic arteries. 3. The Profound Artery, ( Arteria Profunda Femoris ,) the great muscular artery of the thigh, is but slightly inferior in size to the fe- moral itself, and comes from the latter at the distance of from one or two inches below the crural arch. It lies behind the femoral artery, and descends in that situation between the insertion of the adductor brevis and the vastus internus muscle, to the upper part of the insertion of the adductor longus. In this course its size is much diminished by the origin from it of several considerable trunks as follows : a. The External Circumflex, ( Arteria Circumflexa Externa ,) though most frequently a branch of the profunda, sometimes comes from the femoral above or below it a short distance. It goes im- mediately outwards between the rectus femoris muscle and the cru- ralis, giving off some inconsiderable ramifications. While between these muscles it divides into two branches, one of which ascends and the other descends ; the former is distributed to the anterior margin of the gluteus medius and minimus, to the capsule of the joint, the parts about the trochanter major, and anastomoses with the gluteal and the ischiatic. It is said by Meckel, that these anas- tomoses have been found much dilated where the external iliac artery has been taken up. The descending branch is about the size of a crow quill, or even larger ; it first passes obliquely downwards between the rectus femoris and the cruralis, it then descends verti- cally under the anterior margin of the vastus externus, between it and the cruralis, to terminate at the knee, where it becomes super- ficial and anastomoses with the articular arteries. It is, how’ever, principally distributed to the vastus externus and to the cruralis. b. The Internal Circumflex Artery ( Arteria Circumflexa Interna ,) arises from the profunda, near the external circumflex, generally PROFOUND ARTERY, AND ITS BRANCHES. 273 below it, but sometimes the reverse ; in some cases, it comes from the femoral artery itself, near the crural arch. It passes transversely inwards, and dips into the interstice between the pectineus and the psoas magnus, after having given off some small twigs to the heads of the adjoining adductors. It then winds under the neck of the os femoris and divides into two branches ; the upper one goes to the capsular ligament of the joint, to the obturator externus muscle, anas- tomoses with the obturator artery, and sends a branch behind the adductor brevis to the upper part of the adductor magnus : the inferior branch is larger than the other; it descends behind the adductor magnus and is distributed in branches to it, to the gracilis, and to the hamstring muscles, sending upwards some ramifications ( rami trochanterici ) to the parts about the trochanter major, where they anastomose with the external circumflex artery. c. Muscular branches of inconstant origin, and of inconsiderable size, are sent from the profunda to supply the anterior face of the ad- ductor muscles. d. The Perforating Arteries [Rami Profundi Perforantes ) obtain the name from their perforating the adductor magnus, which they do near the linea aspera, so as to get to the back of the thigh. They commonly are four in number, and as they come off successively from the profunda, they are designated numerically. In some cases, however, they are reduced to one, by being concentrated in a com- mon trunk, which penetrating high up the adductor magnus, and afterwards descending on its posterior face, is dispersed upon the muscles on the back of the thigh. The First Perforating Artery arises somewhat below T the trochanter minor, and penetrates the adductor magnus a little below its superior margin. One of its branches ascends towards the trochanter major, where it anastomoses with the external circumflex and with the gluteal, while another descending is spent upon the heads of the flexor muscles of the leg. The Second Perforating Artery gets to the back of the thigh, at the lower magin of the insertion of the gluteus magnus into the linea aspera, being distributed in that region, and to the corresponding portion of the long head of the biceps flexor cruris. The Third Perforating Artery penetrates the Adductor magnus somewhat below the commencement of the short head of the biceps, and is dispersed upon the adductor and the adjacent portion of the flexor muscles. 24 * 11 * CIRCULATORY SYSTEM. The Fourth Perforating Artery penetrates the insertion of the ad- ductor magnus an inch and a half above the opening in it, for the femoral artery; it, in the same way, supplies the posterior face of the adductor and the adjacent muscles. As a summary, it will be readily understood that the profunda is, in this way, through the external and the internal circumflex, and through the perforating arteries, distributed upon all the large mus- cles of the thigh. After the origin of the profunda, the Femoral Artery gives off, at different points of its course- to the opening of the adductor magnus, several twigs the size of a large knitting needle ; which go to the sartorius, the gracilis, the adductors and the extensors on the front of the thigh ; but they are too inconstant to require a more particular description. The Anastomosing Artery (. Arteria Anastomotica ) is the last branch of the femoral, and arises just before it perforates the adductor mag- nus. It descends to the knee, in front of the tendon of the latter, concealed by the internal margin of the vastus internus muscle. It sends off many small twigs to the adjacent muscles, and terminates below by anastomosing with the internal articular arteries. It is about the size of a crow-quill. The Popliteal Artery {Arteria Poplitcea)* is the continuation of the femoral, after the latter has passed through the tendinous insertion of the adductor magnus; and extends from this point to the opening in the interosseous ligament of the leg, just below the head of the tibia. It, first of all, passes from the internal margin of the os femo- ris, to the notch between the condyles ; being there placed in the middle between the internal and the external hamstring muscles, and surrounded by a mass of adipose matter which fills up the hol- low of the ham. It is in contact, anteriorly, with the knee joint, and a little below the latter with the popliteus muscle, descending there between the heads of the gastrocnemius. It is covered, in the greater part of its extent, posteriorly, by the popliteal vein, and by the sci- atic nerve, the latter being more superficial than the vein. The popliteal artery sends off some small branches to the ham- * Anat. Atlas, Figs. 471, 473. POPLITEAL ARTERY, AND ITS BRANCHES. 275 string muscles, and to the parts contained between the latter, which are too irregular and inconstant for description. The following arte- ries, also, come from it: — 1. The Superior Internal Articular Artery (Art. Articularis Supe- rior Interna) arises at or above the internal condyle, and frequently consists in two trunks. It passes through the tendon of the adductor magnus, just above the condyle ; it then begins to distribute itself in branches, some of which are spent upon the lower part of the vastus internus muscle, and others upon the superior internal part of the knee joint. 2. The Superior External Articulating Artery (Art. Articularis Superior Externa ) arises from the popliteal, somewhat above the external condyle of the os femoris. It winds, horizontally, above the external condyle, around the bone, between it and the lower part of the biceps flexor cruris, and is then distributed, also, in two orders of branches, some of which supply the lower part of the vas- tus externus muscle, and others the superior external portion of the knee joint. 3. The Middle Articular artery (Art. Articularis Media) is smaller than either of the above, and sometimes comes from one of them, but generally from the popliteal, on a line with the articulation of the knee. It is distributed to the posterior part of the capsular ligament, to the crucial ligaments, and to the corresponding adipose matter. 4. The Inferior Internal Articular Artery (Art. Articularis Inferior Interna) arises on a line with the inferior part of the internal con- dyle, sometimes lower down. Its origin is very much concealed by the internal head of the gastrocnemius ; it passes beneath the latter, and then between the internal lateral: ligament of the knee and the head of the tibia; consequently, it is covered by the internal ham- string muscles. It afterwards ascends towards tire patella, and is distributed in numerous branches to the inferior internal part of the knee joint, and to the adjacent portion of the tibia. 5. The Inferior External Articular Artery (Art. Articularis Infe- rior Externa) arises near the last, below the external condyle, being concealed by the belly of the plantaris. It passes, horizontally, or nearly so, between the popliteus and the outer head of the gastroc- • 276 CIRCULATORY SYSTEM. nemius, and afterwards beneath the tendon of the biceps and the ex- ternal lateral ligament of the joint, around the external face of the head of the tibia. It gives small branches to these several parts, and is then distributed, by two orders of ramifications, to the superficial and to the more deeply seated parts at the external inferior portion of the knee joint. These several articular arteries anastomose - freely with each other, and are minutely ramified on the knee joint and the contigu- ous structure. They also anastomose with the long descending branch of the external circumflex of the thigh, with the anastomotica of the femoral, and with the tibial recurrent. 6. The Gastrocnemial Arteries ( Arteries Gemellce) are two in number, one for each head of the gastrocnemius. They arise commonly between the superior and the inferior articular arteries, and are about the same size. They penetrate into the muscle, and supply it with blood, terminating their course near the lower part of its bellies. Moreover, some small branches, which go to the contiguous mus- cles, are frequently observed here ; also, the nutritious artery of the tibia. But their number and condition are very inconstant. Near tlie head of the fibula, branches go from the popliteal artery to the upper end of the soleus muscle. Generally, on a level with the aperture in the upper part of the interosseous ligament, but sometimes an inch or two higher up, the popliteal artery terminates by dividing into two large trunks, the Anterior and the Posterior Tibial. The Anterior Tibial Artery* (Art. Tibialis Anterior ) passes for- wards through the foramen of the interosseous ligament, just below the head of the fibula, and runs down the front of the leg and foot, as far as the base of the metatarsal bone of the great toe. In this course, its relative situation is as follows: It rests upon the front of the interosseous ligament of the leg, on a line drawm from the middle anterior part of the head of the fibula to the middle of the ankle joint. Superiorly, it is bounded on the tibial side by the tibialis anticus muscle, and on the other by the extensor longus digitorum : lower down on the leg, the place of the * Anat. Atlas, Fig. 474. ANTERIOR TIBIAL ARTERY, AND ITS BRANCHES. 277 latter is supplied by the extensor pollicis pedis. Somewhat above the ankle joint the artery, leaving the interosseous ligament, rests upon the front of the tibia, and then gets to the top of the foot, be- tween the joint and the annular ligament. Under the ligament it is crossed by the tendon of the extensor pollicis, which gets to its in- ner side, and afterwards continues so. The anterior tibial nerve adheres to it, in its whole length. The following branches come from the anterior tibial artery : 1. The Recurrent Tibial (Art. Tibialis Recurrens) ascends through the upper extremity of the tibialis anticus muscle, having come off from the anterior tibial immediately upon the latter getting to the front of the leg. Several small ramifications pass from it to the heads of the contiguous muscles on the tibia, and to the lower part of the knee joint, where it anastomoses with the lower articular arteries of the knee. 2. Several small arterial twigs are afterwards sent to the mus- cles and to the periosteum of the leg, as the anterior tibial descends ; but they are too inconstant in size and position to require descrip- tion. 3. The Internal Malleolar Artery (Art. Malleolaris Interna ) arises from the anterior tibial, an inch or two above the ankle joint. It descends, inwardly, between the tibia and the tendon of the tibialis anticus, and, having gained the internal malleolus, is dis- tributed by branches upon it and upon the adjacent portion of the articulation. 4. The external Malleolar Artery (.Art. Malleolaris Externa ) con- sists most commonly in two arterial twigs of small size, but frequently in one only. It arises in front of the ankle joint, and going out- wardly between it and the tendons of the extensor digitorum longus, is spent upon the external face of the articulation, where it inoscu- lates with the peroneal artery. This artery is sometimes of considerable size, in which case it also supplies the outer part of the tarsus, and is a substitute for the next. 5. The Tarsal Artery (Arteria Tarsea') arises from the anterior 278 CIRCULATORY SYSTEM. tibial, somewhat below the ankle joint near the scaphoides, and, going outwardly beneath the extensor brevis digitorum muscle, it is distributed in branches near the external ankle, and upon the outer upper surface of the tarsus. It anastomoses with the external mal- leolar, with the external plantar, and with the metatarsal artery. Some small branches also pass from the anterior tibial at this point to the upper internal face of the tarsus. 6. The Metatarsal Artery [Art. Metatarsea ) arisesjust below the last. It is directed forwards and outwards beneath the extensor brevis muscle, and forms a sort of arch at the roots of the metatarsal bones. It furnishes several ramifications to the upper surface of the tarsus and the contiguous parts; amongst them is an interosseal artery for each of the three outer interosseal spaces. These arteries communicate, by small anastomoses, with the arteries of the sole of the foot, both at the bases and at the ends of the metatarsal bones, and terminate in front by supplying the backs of the small toes. This artery is sometimes a branch of the tarsal. 7. The Dorsal Artery of the Great Toe [Art. Dorsalis Hallucis ) arises from the anterior tibial at the root of the first metatarsal bone. It runs along the superior face of the first metatarsal interval, and having reached the anterior end of it, divides into two branches, one of which goes to the back of the great toe and the other to the tibial margin of the next toe. / The Anterior Tibial, in its course from the ankle joint to the base of the first metatarsal bdne, is sometimes called Pedal ( Arteria Pedicea;) at the posterior end of the first metatarsal interval, being still of considerable size, it sinks down to the sole of the foo|, and joins itself to the external plantar artery at this point. It frequently happens (hat the anterior tibial being small in its course down the leg, is joined by the continued trunk of the pero- neal, which perforates the interosseous ligament somewhat above the ankle joint. Afterwards the trunk formed by this union, being of considerable s'ze, follows the course and has the distribution mentioned. The Posterior Tibial Artery ( Arteria Tibialis Posticu*) is some- * Anat. Atlas, Fig, 475. THE POSTERIOR TIBIAL ARTERY. 279 times called, at its commencement, till it gives off the peroneal, tibio-peroneal; it extends from the head of the tibia to the sinuosity of the os calcis, in a line from the middle of the ham to the internal ankle. It is at the tibial side of the back of the leg, on the posterior face of the flexor longus digitorutn muscle; and covered by the fascia of the latter. In the two superior thirds of its course, it is concealed behind by the gastrocnemius and the solaeus muscle: in the inferior third, it is at the internal margin of the tendo-achillis. At the ankle joint, before it passes into the sinuosity of the os calcis, it is between the tendon of the tibialis posticus and that of the flexor longus pollicis pedis, being covered by the laciniated ligament. It is accompanied, at its external margin, by the posterior tibial nerve. The posterior tibial artery is distributed after the following manner: 1. The Peroneal Artery ( Arteria Peronea ) is its first branch of any importance, and is but little smaller than the continued trunk. It arises an inch or two below the origin of the anterior tibial, and extends, on the posterior face of the leg, to the external ankle. It is, in some measure, concealed by the posterior side of the fibula, being placed there between the origin of the flexor longus pollicis muscle and the external edge of the tibialis posticus. It is covered behind by the flexor longus pollicis, by the soleus, and by the gas- trocnemius; it is, therefore, deep and of extremely difficult access in the living body. In this course, it sends small branches to the gastrocnemius, to the soleus, and to the other contiguous muscles on the back of the leg. After having descended two-thirds of the length of the fibula, it divides into an anterior and a posterior branch. The former traverses the interosseous ligament, and descending in front of it, covered by the muscles which arise from the lower part of the fibula, is distributed upon the upper external part of the foot near the ankle joint. The posterior branch continues in the primitive course of the peroneal artery at the internal posterior margin of the fibula, and descending behind the tibio-peroneal articulation, reaches the external face of the os calcis: it detaches several small ramifications to the contiguous muscles; and, upon the os calcis, is divided into twigs which supply the adjacent parts and the integu* ments below the external ankle. 2S0 CIRCULATORY SYSTEM. 2. In the descent of the posterior tibial artery to the hollow of the os calcis, it detaches several small muscular branches, princi* pally to the tibialis posticus, and to the flexors of the toes. One twig, which is the nutritious artery of the tibia, comes from its upper part when not furnished from the popliteal artery, and enters the foramen on the posterior surface of the bone. While the posterior tibial is in the hollow of the os calcis, be- tween it and the abductor muscle of the great toe, it furnishes some small twigs to the contiguous muscles, and to the integuments of the sole of the foot ; it then divides into two branches, the Internal and the External Plantar Artery.* The Internal Plantar Artery [Art. Plantaris Interna ) is much smaller than the other. It advances between the abductor pollicis pedis and the internal inferior margin of the bones of the foot, and terminates at the anterior end of the first metatarsal bone, by join- ing the internal digital artery of the great toe. In this course, it sends continually, small ramifications to the muscles of the great toe and to the flexor brevis digitorum pedis. One of the largest of these ramifications comes off near the os scaphoides, and cruises along the internal margin of the abductor pollicis to its anterior end ; another becomes superficial on the sole of the foot, between the ab- ductor pollicis and the flexor brevis digitorum, and goes forward as far as the other. The External Plantar Artery [Art. Plantaris Externa ) is the con- tinuation of the posterior tibial, and diverges from the internal plantar towards the outer margin of the sole of the foot, between the flexor brevis digitorum pedis and the flexor accessorius. Having reached the internal margin of the abductor minimi digiti, it ad- vances along the latter to the base of the metatarsal bone of the fourth toe ; it then makes a curvature forwards and inwards across the metatarsal bones, between the tendons of the flexor longus digi- torum and the interosseous muscles, to the first metatarsal interval, where it is joined by the anterior tibial artery from above. This curvature is the Arcus Plantaris, of which the concavity is behind and inwards. The external plantar artery is distributed as follows : — Anat. Atlas, Figs. 476 to 479, inclusive. POSTERIOR TIBIAL ARTERY, AND ITS BRANCHES. 281 Shortly after its origin, it detaches a branch which goes backwards and outwards, and which keeping close to the os calcis in front of its tuberosity, is distributed to the heads of the muscles arising from it, and to the outer surface of the heel ; it also sends an arteriole along the external edge of the abductor minimi digiti. At the base of the fourth metatarsal bone arises a branch called the External Digital Artery of the Little Toe. It goes at first deeply along the internal margin of the muscles situated on the fifth meta- tarsal bone, and, afterwards, at the head of the latter, it gets between them and the bone, and is distributed along the external margin of the little toe. The four Digital Arteries of the foot arise next successively from the arcus plantaris, at or near the metatarsal intervals. They run along the inferior surface of the interosseous muscles, getting to the bases of the first phalanges above the transversalis pedis. Each artery there bifurcates, so as to supply the opposed surfaces of the adjacent toes, in the same way that the digital arteries of the hand are distributed. The digital artery of the first metatarsal interval which comes from flie internal extremity of the arcus plantaris, where the anterior tibial artery joins the latter, goes forwards concealed by the flexor brevis of the great toe: just behind the sesamoid bones, it sends a branch which supplies the internal side of the great toe, being its in- ternal digital artery, and anastomoses with the internal plantar artery. What remains of it, is still a trunk of considerable magnitude, which advancing to the space between the first phalanx of the great toe and of the toe next to it, there bifurcates, as mentioned, so as to supply the opposite sides of these two toes. The Perforating Arteries, as they are called, are of two kinds, the anterior and the posterior. The former arise from the convexity of the plantar arch and being destined principally to the interosseous muscles, anastomose at the anterior end of the latter with the branches from the metatarsal artery, which supply their superior surface. The posterior perforating arteries come also from the plantar arch, and penetrating the posterior end of the interosseous spaces, anastomose also with the metatarsal arteries on the dorsum of the foot. The preceding trunks of the internal and of the external plantar Von. II.— 25 282 CIRCULATORY SYSTEM. arteries are the principal ones which are found in the bottom of the foot, but from them there arise an immense number of arte- rioles ; which, descending vertically between the interstices of die muscles and of the aponeurosis plantaris, supply the adipose matter and the skin of the sole of the foot, so as to render them extremely vascular. CHAPTER III. Of the Veins. The veins of the body, assembling from differing points, unite successively into the ascending and into the descending vena cava, which discharge their blood into the right auricle of the heart. The veins of the head, of the upper extremities, and of the thorax, run into the descending cava, while the veins of the abdomen and of the lower extremities concur to form the ascending cava. SECT. I. — OF THE VEINS OF THE HEAD AND NECK.* Many of these veins are described elsewhere with the encephalon and with the eye, to wdiich accounts the reader is referred. The others are more superficial, and arise as follows : The Facial Vein ( Vena Facialis) observes the course of the facial artery, being placed behind the latter. It arises upon the forehead by a considerable number of roots, which unite into a single trunk called the frontal vein. This vein descends from the forehead, over the root of the nose, along the internal canthus of the orbit. It there receives re-enforcements from the eyelids, and anastomoses with the ophthalmic veins ; descending afterwards, in the same v r ay with the facial artery, and taking the name of facial vein, it receives successively the veins from the nose, from the outer Anat. Atlas, Figs. 480, 481, 482. OF THE VEINS. 483 side of the orbicularis palpebrarum, from the upper and lower lips, and from the muscles and the integuments of the face. It descends to the neck at the anterior margin of the masseter muscle, and is then augmented by the ranine, the submental, and the inferior pala- tine veins, and immediately afterwards goes into the internal or the external jugular vein. The Ranine Vein ( Vena Ranina ) arises at the point of the tongue, and then goes along its under surface, where it can be readily seen by turning up the end of the tongue. It joins the facial near the posterior margin of the mylo-hyoideus muscle. The Submental Vein ( Vena Submentalis ) arises by ramuscules from the sublingual and the submaxillary gland, and from the contiguous muscles. It joins the facial vein a little below the last: sometimes it runs into the superior thyroidal vein. The Inferior Palatine Vein ( Vena Palatina Inferior ) arises princi- pally from the soft palate and from the tonsil gland, but receives a few twigs from the contiguous parts. It corresponds with the in- ferior palatine artery, a branch of the dorsal lingual, (Dorsalis Lin- gute ;) and descends the pharynx along side of it, and terminates in the trunk of the facial near the last. The Lingual Vein ( Vena Lingualis ) has its origin from a plexus of veins situated on the root of the tongue under its lining membrane, between the epiglottis and the foramen caecum : branches are also sent to it from the muscular structure of the tongue, from the sublin- gual gland and from the adjacent muscles, and it anastomoses with the vena ranina. It goes backwards between the hyoglossus and the mylo-hyoideus muscle, along the superior margin of the os hyoides, and then discharges into the internal jugular vein near the facial. The Pharygeal Vein (Vena Pliaryngea) arises from a plexus of veins belonging to the pharynx, and discharges either into the lingual or into the internal jugular near it. The Superior Thyroid Vein (Vena Thyroidea Superior ) corre- sponds with the distribution of the superior thyroid artery, in the 484 CIRCULATORY SYSTEM. origin of its primitive roots. Having collected the latter into one or more trunks, it passes upwards and backwards beneath the sterno-hyoid and thyroid muscles, and discharges itself into the upper part of the internal jugular, or into one of the large branches of the external jugular. The Occipital Vein (Vena Occipitalis) arises from the branches of the occipital artery, and following the course of the latter, be- neath the muscles connected with the mastoid process of the tem- poral bone, it is discharged into the upper part of the internal jugu- lar or of the external ; more rarely into the latter. The Diploic Veins (Vence Diploicce) have been described in the account of the bones of the cranium as situated between the two tables in the diploic structure, and commence by very fine capillary tubes from its lining membrane. The one in the frontal bone dis- charges itself into the frontal vein, that in the occipital bone into the occipital vein, and the two in the parietal bone into the deep tem- poral veins. They do not open each by one orifice, but by several, which make their terminations not very distinct or abrupt : besides which, they communicate freely by a crowd of ramuscules, with the veins of the scalp on the outside, and with those of the dura mater internally. The Superficial Temporal Vein ( Vena Temporalis Superficialis ) corresponds with the temporal artery, and takes its rise from the terminating ramifications of the latter. It is immediately below the skin. Its branches communicate freely with each other, and with the branches of the frontal and of the occipital vein: at the zygoma it receives the trunk of the Middle Temporal Vein, which, collecting the blood from the temporal muscle and other parts within the zygoma, perforates the temporal fascia to discharge itself into the superficial temporal vein. The Temporal Vein, (Vena Temporalis ,) which is formed by the junction of the Middle and the Superficial Temporal, descends over the root of the zygoma, in company with the artery, and penetrates, like the latter, through the substance of the parotid gland. It is joined, near the neck of the lower jaw, by the internal maxillary vein. It is also joined, in its descent through the parotid gland, by VEINS OF THE HEAD AND NECK. 285 the anterior auricular veins, by the parotid veins, and by the trans- verse facial, all of which correspond with the arteries of the same name. The temporal vein, on issuing from the parotid gland, im- mediately afterwards becomes the External Jugular ; but, occasion- ally, it ends wholly, or in part, in the Internal Jugular. The Internal Maxillary Vein (Vena Maxillaris Interna) is derived from the terminating ramifications of all the arteries into which the internal maxillary is divided; it is, therefore, composed of the spheno-palatine vein, which brings the blood from the nose, of the infra-orbital, of the pterygoids, inferior maxillary, deep-seated tem- poral, and so forth, with the exceptions of the vein, which might belong to the middle artery of the dura mater, but which does not exist according to Portal and to Hippolytus Cloquet. By the aid of the spheno-palatine vein, the internal maxillary communicates with the sinuses in the bottom of the cranium, by branches, called the Emissary Veins of Santorini,* which pass through the foramen ovale, rotundum, and spinale. It also communicates with the plexus of veins on the side of the pharynx. The External Jugular Vein (Vena Jugularis Externa) is generally the continuation of the temporal. It descends on the neck almost vertically, between the platysma myodes and the sterno-mastoideus, in the direction of the fibres of the first, and crossing those of the latter obliquely. Just behind the clavicle, at the external margin of the sterno-mastoideus, it opens into the subclavian vein, in front of the scalenus anticus muscle. Sometimes, instead of one trunk only, there are two or three, which unite at a variable distance above the subclavian. This vein varies also in its size, and in the branches from which it is made up : sometimes it receives the facial vein, and on other occasions the latter runs, as stated, into the internal jugular. The condition and arrangement of the internal and external jugulars, are, indeed, so inconstant, in regard to the trunks that compose them, that it is scarcely possible to give more than a very general description of them with tolerable accuracy. The external jugular, in going down the neck, anastomoses more or less with the internal jugular, either directly or by its branches: one of these anastomoses is found near the angle of the lower jawg, about the trunk of the facial vein, and is so large as to explain the * Obs. Anat. chap. iii. p. 74. 25 * 286 CIRCULATORY SYSTEM. difference of opinion among anatomists in regard to the latter’s ter- mination. Sometimes the occipital vein, or a large trunk from it, joins the external jugular. At the lower part of the neck, the ex- ternal jugular is augmented by the superficial cervical veins. Some of these come from the lower part of the neck, near the shoulder, and join the jugular just above the clavicle ; others are placed on the lower front part of the neck, above the sternum, and there form with each other a remarkable and an irregular plexus, consisting in numerous meshes. It frequently happens that the external jugulars of the two sides, just before they terminate, anastomose with each other by a large horizontal trunk, which runs just above the end of the sternum, in front of the sterno-mastoid, sterno-hyoid, and the sterno-thyroid muscles : this trunk, on other occasions, goes more deeply, and behind these muscles, from one subclavian vein to another, or to a jugular; its mode of attachment is, indeed, much varied: when it exists, however, it frequently receives several of the superficial veins of the neck, and the inferior thyroideal. The Internal Jugular Vein ( Vena Jugularis Interna ) extends from the basis of the cranium to the internal margin of the first rib, at the insertion of the .scalenus anticus muscle. The lateral sinuses of the dura mater, receiving ultimately all the blood of the brain, of the eye, and a portion of that of the nose, convey it from the cra- nium through the posterior foramina lac.era; where they are joined to the upper end of the internal jugular veins, the lining membrane of each sinus being continuous with that of its respective vein. Each vein is somewhat enlarged at its commencement, which is therefore called its Gulf or Sinus ; the right vein is frequently larger than the left. The internal jugular then descends in front of the transverse processes of the vertebra of the neck, on the outer side of the inter- nal and of the primitive carotid artery, and of the pneumogastric nerve. It is concealed above by the styloid process of the temporal bone, and the muscles belonging to it ; it is crossed half way down the neck, by the omo-hyoideus muscle ; and, in the greater part of its course, is beneath, and nearly parallel with the anterior edge of the sterno-mastoideus. Having got behind the sternal end of the cla- vicle, it is joined at the internal edge of the scalenus anticus by the subclavian vein, and the union of the two forms the vena inno- minata. The internal jugular receives frequently the large anastomotic VEINS OF THE HEAD AND NECK. 287 branch, just alluded to, from the external jugular, at the under mar- gin of the parotid gland, between the digastric muscle and the lower jaw, and it is in this vicinage that it is generally re-enforced by the Occipital; the Lingual; the Facial; the Pharyngeal; and the Superior Thyroidal Veins, that have been described. The Vena Innominata, or Brachio Cephalic Vein is the trunk formed on either side by the junction of the subclavian with the internal jugular. On the right side it looks like the continuation of the internal jugular, and descends in contact with the right pleura, behind the right side of the sternum, for the distance of an inch or thereabouts. On the left side it crosses behind the superior end of the sternum, descending obliquely in this course, from left to right, until it joins the trunk on the right side. It lies in front of the great vessels proceeding from the arch of the aorta ; and is much longer than the trunk of the other side. A common name for it is the Transverse Vein. The Vena Cava Superior, or Descendens, arises from the junction of the two vense innominatse. It begins between the cartilage of the first rib on the right side, and the arch of the aorta, and descends to the superior posterior part of the right auricle, into which it empties itself. Its course is not entirely vertical, but inclining somewhat to the left side and forward. It is about three inches long. The supe- rior third of it is free, and is in contact on the right with the pleura, and on the left with the arteria innominata ; the remaining portion of it is invested by the pericardium, and has the aorta on its left an- terior face.'* The following venous trunks discharge into the vense innominatse, or into the descending cava. The Inferior Thyroidal; the Verte- bral ; the Superior Intercostal ; the Internal Mammary ; the Vena Azygos, and some others of smaller size. 1. The Inferior Thyroid Vein ( Vena Thyroidea Inferior ) arises from the inferior part of the thyroid gland, by many small roots, which anastomose with those of the opposite side. It descends in front of the trachea, involved in the loose cellular and fatty matter * In some very rare cases there have been two descending venas cavae, one for the right side and the other for the left. J. F. Meckel. 288 CIRCULATORY SYSTEM. lying upon it, and empties itself into the left brachio-cephalic vein, or Transverse Vein. There is occasionally another thyroid vein, called the middle, which discharges itself into the lower part of the internal jugular. 2. The Vertebral Vein ( Vena Vertebralis ) is placed in the same canal with the vertebral artery. At its upper extremity it anasto- moses with the occipital sinus, by a branch lodged in the posterior condyloid foramen. In its descent of the canal of the transverse processes, it communicates at each intervertebral foramen with the vertebral sinuses, and also receives a branch from the muscles of the neck. It issues at the sixth transverse process, and going on the right side behind the subclavian artery, but on the left, in front of it, is finally emptied into the commencement of the vena in- nominata. 3. The Superior Intercostal Vein ( Vena Intercostalis Superior) is on the right side an inconsiderable trunk, sometimes deficient, which commences by branches belonging to the first two intercos- tal spaces, and empties into the vena innominata just below the vertebral. On the left side it is much larger, and arises from the six or eight superior intercostal spaces. It lies on the left side of the bodies of the upper dorsal vertebrae, and at each intercostal space, as it ascends, receives its contribution of an intercostal vein, corresponding with the intercostal artery ; it also receives branches from the oesophagus, and about the third dorsal vertebra the left bronchial vein is discharged into it. Issuing from the thorax above, it discharges into the left vena innominata near its commence- ment. 4. The Internal Mammary Vein. ( Vena Mammaria Interna ) arises from the terminating branches of the internal mammary ar- tery, and in its situation and course corresponds with the latter. It is re-enforced by small branches from the diaphragm, the pericar- dium, and the thymus gland. Each internal mammary vein dis- charges itself on its respective side into the vena innominata near the superior intercostal. 5. The Vena Azygos* is placed in the posterior mediastinum. * Anat. Atlas, Figs. 489, 490. VEINS OF THE HEAD AND NECK. 289 on the right anterior margin of the Dorsal Vertebrae, and dis- charges itself in making an arch forwards over the root of the right lung, into the descending cava, just above the introduction of the latter into the pericardium. Its orifice there is supplied with a membranous duplicature or valve, which prevents the blood once discharged from re-entering it. The valve is sometimes double, and also somewhat removed from the orifice. It was the observa- tions of these valves, first of all, which called the attention of Syl- vius and of Charles Etienne to their existence in other veins. This vein begins in the abdomen, either by an anastomosis with the ascending cava, or with the upper lumbar vein ; it then ascends into the thorax through the aortic orifice of the diaphragm, and continuing to mount upwards beneath the pleura it lies on the right side of the thoracic duct, and crosses in front of the intercostal arteries of the right side. In this course, it receives from the ten inferior intercostal spaces of the right side, their respective inter- costal veins corresponding in their origin and course with the in- tercostal arteries. About the sixth vertebra of the back, it receives a trunk ( Vena Hemiazygos) which is formed from the four or six lower intercostal veins of the left side, and commences in the ab- domen, also by anastomosis with the left emulgent vein or the left superior lumbar, and which gets into the thorax either through the aortic orifice of the diaphragm, or through a special opening to the left of it. The vena azygos also receives some small ramifica- tions from the oesophagus, and near the fourth dorsal vertebra, the right bronchial vein is discharged into it. Other small ramifica- tions join it from the parietes of the descending cava, of the aorta, and of the right pulmonary artery. Branches also proceed to it, or to the intercostal veins from the interior of the vertebral canal at each intervertebral foramen. This vein is commonly spoken of by anatomists, as forming a great anastomosis between the ascending and the descending cava. The tendency to establish this anastomosis is strikingly confirmed by a preparation made by myself, when I was a student in this institution in 1813 ; and now in the Anatomical Cabinet. In it the ascending cava, instead of emptying, as usual, into the lower part of the right auricle, ascends on the right side of the dorsal verte- brae, and supplanting in situation and office the vena azygos, dis- charge itself into the descending cava, in a manner corresponding 290 CIRCULATORY SYSTEM. with the vena azygos, by making a curvature forwards over the root of the right lung. The Sinuses of the Vertebral Column* ( Sinus Columnce Verte- bralis ) are situated in the vertebral cavity, on the posterior face of the bodies of the vertebrae, and in front of the dura mater of the spinal marrow. They are two long veins, one at each margin of the posterior vertebral ligament, and extend from the foramen mag- num occipitis to the inferior end of the sacrum. They are main- tained in their places by a loose cellular tissue between the bones and the dura mater, and therefore, unlike the sinuses of the brain, are entirely independent of the dura mater. These sinuses are small where they begin in the sacrum, and are there merely two cylindrical veins surrounded by a loose cellular sub- stance, and which have an anastomosis between them. In ascend- ing the spine they enlarge, but not continually, as they are some- what smaller in the cervical than in the dorsal vertebra. On the body of each vertebra they are rather larger than on the interverte- bral substance : this gives them a knotted appearance, which is es- pecially distinct in the loins. At the middle of each vertebra they are joined to one another by transverse branches, which pass beneath the posterior vertebral liga- ment, and receive the veins belonging to the cellular structure of the bone. Externally, they communicate with the vertebral veins in the transverse processes of the neck, with the intercostal, and with the lumbar veins, as an opening occurs between the adjacent vertebra. They also receive many delicate veins from the dura mater of the spine. These two trunks terminate at their upper end by an anastomosis, through the anterior condyloid foramen, with the internal jugular : they also terminate by anastomosis with the ante- rior occipital sinus and with the vertebral veins. From the arrangement of these sinuses, it appears that each bone of the spine has its own venous system or circle ; which also is the case in regard to the corresponding section of medulla spinalis in early life, when it occupies the whole length of the spine. Each of these circles, by the freedom of their anastomoses, therefore, forms a link in a long chain of venous circles belonging to the structure of the spine. * G. Bresehet, Essai sur les Veines du rachis. Paris, 1819. Anat. Atlas, Figs. 483, 484, 485. VEINS OF THE UPPER EXTREMITIES. 291 SECT. II. — OF THE VEINS OF THE UPPER EXTREMITIES.* The veins of the upper extremities are superficial and deep-seated, and arise from the distribution of the arteries. The Deep-seated Veins are found in company with each arterial ramification, there being two veins to one artery generally. We thus have them observing the course of the arteries of the hand, of the fore-arm, of the arm, and of the shoulder. At the bend of the arm, the two radial and the two ulnar veins coalesce into the two brachial veins, which attend the brachial artery, one on each of its sides, and at intervals throw anastomotic branches across it. Some- times, but one of these trunks exists, with the exception of the lower part of the arm, where there are most commonly two. The trunk (or trunks, as the case may be,) is joined by the basilic vein, at a point varying from the middle of the arm to the axilla. These venae comites, or satellites, are invariably called after the arteries which they attend, and having no difference from the latter in relative situation, a farther description of them may be dis- pensed with. The Superficial Veins lie between the skin and the brachial apo- neurosis, and are considerably larger than the preceding. Their earliest roots are seen on the back of the fingers ; they then appear on the back of the hand, on the posterior of the lower end of each interosseous space. There are commonly six trunks in all : the one on the ulnar side of the hand and the three next to it, converge to- wards the middle of the back of the carpus into a single trunk; the two others, one of which comes from the thumb and the other from the back of the fore-finger, converge to the outer end of the carpus, and there form a single trunk also. Between these several trunks, there are frequent anastomoses, and they, finally, assemble into two principal branches called the Cephalic and the Basilic Vein. The Cephalic Vein (Vena Cephalica , Radialis Cutanea ) is the trunk which comes from the thumb and from the fore-finger, and has at first the name of Cephalica Pollicis. It ranges along the an- terior and radial margin of the fore-arm, and receives, continually, * Anat, Atlas, Figs. 486, 487, 488, 494. 292 CIRCULATORY SYSTEM an augmentation from small collateral branches on the back of the fore-arm. Having reached the bend of the arm, it then ascends along the external margin of the biceps flexor cubiti till it touches the lower margin of the pectoralis major muscle ; it then rises superficially along the interstice between this muscle and the deltoid, to within eight or ten lines of the clavicle, where it dips down to join the axillary vein. Along the arm, it receives some small secondary cutaneous branches. The Basilic Vein ( Vena Basilica , Cubitalis Cutanea ) is larger than the cephalic, and begins by the trunk which comes from tire ulnar side of the back of the hand, and is first called the Vena Salvatella. On the fore-arm, the basilic frequently consists in two long trunks, the anterior and the posterior ; in this case the posterior is the prin- cipal one, and runs along the internal posterior edge of the ulna, until it comes to the bend of the arm ; it then mounts over the latter, rising obliquely in front of the internal condyle. The anterior branch begins near the palm of the hand, runs up in front of the ulnar side of the fore-arm, and discharges itself into the median basilic vein over the brachial artery in front of the bend of the arm. These two trunks, or one as the case may be, receive the cutaneous veins belonging to the ulnar side of the fore-arm. Above the elbow joint, the basilic gets below the fascia of the arm at the inner edge of the biceps, and about the middle of the arm becomes, by its junction with the venrn satellites, the Brachial Vein; but sometimes, as mentioned, this junction occurs much higher up. The Median Vein '{Vena Mediana ) arises, by branches, from the -wrist, from the palm of the hand, and from the middle of the front of the fore-arm. It forms a trunk which ascends in front of the fore-arm, and which a few inches below the bend of the arm, di- vides into two. One branch runs outwardly, in ascending for an inch or two, and joins at the outer side of the bend of the arm, the cephalic vein ; it is called, therefore, the Median Cephalic. The other branch continues to ascend, and, crossing obliquely the di- rection of the brachial artery, it receives, near the latter, the an- terior trunk of the basilic vein, and somewhat above the bend of the arm, runs into the proper basilic vein : it is called the Median Basilic. VEINS OF THE UPPER EXTREMITIES. 293 There is frequently a departure from the preceding arrangement of the median vein ; the most common is where a trunk begins from the cephalic below the bend of the arm, and runs obliquely in front of the latter to join the main trunk of the basilic above the elbow joint. This oblique trunk stands in the place of median cephalic and median basilic, and receives successively the median, the anterior and the posterior basilic. It is frequently the median itself, and has a short anastomosis, in such case, with the cephalic vein. The Superficial Veins anastomose frequently with each other, so that, when they are all fully injected, a plexus of veins is found immediately beneath the skin of the upper extremity from one end to the other. The Venae Satellites also anastomose frequently by branches which cross the artery to which they belong. At the bend of the arm, at the wrist, and in different places, there are ' also anastomoses between the deep-seated and the superficial veins. The Axillary Vein ( Vena Axillaris ) results from the union of the basilic with the brachial vein. It is below and in front of the axil- lary artery, being included in the same sheath with it, and also in- volved with the axillary plexus of nerves. It retains its name from the lower margin of the arm-pit to the under surface of the clavicle, where, like the artery, it is then called subclavian. In this course it is joined near the points where the corresponding arteries are given off, by the Anterior and the Posterior Circumflex Vein ; by the Scapular ; and by the External Thoracics. The Subclavian Vein ( Vena Subclavia ) extends from the termina- tion of the axillary to the vena innominata, where the latter is con- stituted by the junction of the internal jugular with the subclavian. In its course it goes under the subclavian muscle, and is in front of the subclavian artery from the beginning, but near it : afterwards it is separated from the artery by the latter going between the an- terior and the middle scalenus muscle ; whereas the vein runs over the anterior end of the first rib, in front of the insertion of the scalenus anticus. The Subclavian Vein is joined by some branches coming from the shoulder and from the lower part of the neck ; and, at the Vol. II.— 26 294 CIRCULATORY SYSTEM. outer margin of the origin of the sterno-mastoid muscle, it is aug- mented by the addition to it of the external jugular. It terminates at the internal margin of the scalenus anticus, as mentioned in the vena innominata. SECT. III. — VEINS OF THE LOWER EXTREMITIES.* The veins of the lower extremities, like those of the upper, are deep-sealed and superficial. The former follow the course of the arteries, and are the venre satellites; there being, for the most part, two veins for every artery as far up as the ham, and also as re- gards the muscular branches of the thigh. These veme satellites adhere closely to the artery, and are separated from each other by the latter. They also have frequent anastomoses with each other across the artery. The Popliteal Vein ( Vena Poplitea) is a single trunk formed by the union of the anterior tibial, the posterior tibial, and the peroneal vein. It begins on the posterior part of the head of the tibia, and extends upwards through the ham to the perforation in the adductor magnus muscle, which transmits the femoral artery. It is situated on the posterior face of the popliteal artery, to which it closely adheres; and behind it is the popliteal nerve, the continuation of the great sciatic. The Femoral Vein ( Vena Femoralis ) is the continuation upwards of the popliteal: it at first is placed behind. the artery, but in a short space it gets to its interior face, and continues to adhere to it, in that situation, up to Poupart’s ligament, where it becomes the ex- ternal iliac vein. At the usual distance below the groin, where the arteria profunda is given off’, the femoral vein receives the vena cruralis profunda, which is derived from the branches of this artery, and is rather more superficial than it; the two, however, adhere closely together. Just below Poupart’s ligament the femoral vein receives several small branches of veins corresponding with the ex- ternal pudic arteries. * Anat. Atlas, Figs. 493 to 497, inclusive. VEINS OF THE LOWER EXTREMITIES. 295 The Small Saphena ( Vena Saphena Minor Externa ) commences by several small branches near the external side of the top of the foot, and the external ankle ; a trunk is formed by them behind the latter, which ascends along the tendo-achillis and the posterior face of the gastrocnemius muscle, collecting several small veins from the back of the leg in its course. This vein is superficial in its whole length, being placed immediately beneath the skin. In the ham, it goes for a short distance along the internal face of the popliteal nerve, and then makes a dip through the adipose matter there to empty into the popliteal vein. It is said, by Portal, that the branches of this vein become very apparent in persons who suffer from podagra, and from enlarge- ment of the lymphatic glands in the ham. In such case, their distention has been relieved by the application of leeches along them. The Great Saphena ( Vena Saphena Magna , Interna ) is also super- ficial, has its primitive roots coming from the internal upper part of die foot, and from the sole of the latter. These branches are as- sembled into a trunk which passes upwards in front of the internal ankle, then ascends along the internal face of the leg, in a line cor- responding with the posterior margin of the tibia. The great saphena continues its ascent over the internal condyle near its posterior part, and then mounts up the internal face of the thigh, in aline cor- responding nearly with the internal margin of the sartorius muscle. It finally terminates in the femoral vein, about twelve or eighteen lines below Poupart’s ligament, an opening being left in the fascia femoris for this purpose. In the whole of this course the great saphena is situated between the skin and the fascia of the lower extremity ; it is, consequently, so superficial, that in persons of moderate corpulency it is very visible, and by slight pressure above, along with the erect position, it becomes so much swollen, that it is easily opened Avith the lancet where it passes OA'er the internal ankle. It receives, in its ascent, small branches from the anterior and posterior part of the leg, from the corresponding surfaces of the thigh, and near its termination it gets a few of the external pudendal veins. When the great and the small saphena veins are successfully in- jected, their branches are seen to form a considerable number of 296 CIRCULATORY SYSTEM. anastomoses, which thereby produce a remarkable venous net-work, just beneath the skin of the whole inferior extremity. SECT. IV. — VEINS OF THE ABDOMEN.* The External Iliac Vein, ( Vena lliaca Externa ,) being the con- tinuation of the femoral vein, passes into the abdomen, under Pou- part’s ligament, and in contact with the internal margin of the ex- ternal iliac artery. It there receives the epigastric, and the circum- flex iliac veins, corresponding with the arteries of the same name ; it also receives a vein of some size, which enters by the abdominal canal in adhering to the spermatic chord, and which comes from the coats of the testicle. f It keeps then along the internal side of the artery, somewhat behind it, at the superior margin of the pelvis, and joins the hypogastric vein opposite to the sacro-iliac junction, and thereby forms the common iliac vein. The Hypogastric Vein [Vena Hypogastrica, lliaca Interna ,) comes from the inferior part of the pelvis in front of the sacro-iliac junction, and in company with the hypogastric artery. It arises by branches corresponding with the distribution of the latter to the viscera of the pelvis, and to its external parts ; these branches are so numerous at particular points, and have such frequent anastomoses, that they are formed into a Plexus. Thus, there is a hemorrhoidal plexus for the lower part of the rectum, a vesical for the bladder, a sacral for the sacrum, a pudendal for the parts of generation in the male, a vaginal for the vagina, and an uterine for the uterus of the female. The Plexus Plemorrhoidalis, besides being connected with the hypogastric, also anastomoses with the branches of the vena por- tarum. The Plexus Vesiealis is different in the two sexes. In man it commences at the extremity of the penis by several branches, which unite into two trunks of considerable size, the Venae Dorsales Penis.j: The latter go along the upper face of the penis, near or at its middle, * Anat. Atlas, Figs. 489 to 492, inclusive. f H. Cloquet, Traite D’Anat. \ They are frequently found to unite into a single trunk, called, in such case, the Vena Magna Ipsius Penis. VEINS OF THE ABDOMEN. 29? to the symphysis of the pubesj continually receiving in this course small trunks from the integuments of the penis and from the scrotum. They then get into the pelvis between the root of the penis and the symphysis pubis, and continue horizontally backwards on the side of the prostate gland, of the vesiculae seminales, and of the lower fundus of the bladder. They receive many branches from these parts, which, with the frequency of the anastomoses about here, con- stitute the vesical plexus. The latter, finally, discharges into the lower part of the hypogastric vein by two or more branches. In the female the vesical plexus begins on the dorsum of the cli- toris, by several branches coming from it and from the vulva ; they get into the pelvis under the symphysis pubis, and on the sides of the urethra and of the vagina, forming upon the lower part of the bladder, and on the side of the vagina, with the assistance of branches from these viscera, a remarkable plexus, which also empties into the internal iliac vein. The Plexus Sacralis consists in an order of veins, anastomosing freely with each other, and corresponding with the middle and the lateral sacral veins. They communicate with the inferior end of the vertebral sinuses through the anterior sacral foramina ; they also communicate with the hemorrhoidal and with the vesical veins. They terminate in the venous trunks, nearest the origin of the ar- teries from which they are derived. The Plexus Pudendalis is derived from the branches of the inter- nal pudic vein which go to the perineum, to the posterior part of the scrotum, and to the integuments of the under part of the penis. The trunk formed by the assembling of these several ramifications, follows the course of the internal pudic artery to which it belongs, and gets into the pelvis at the lower part of the sciatic foramen, where it contributes to the formation of the hypogastric vein. ’ The Plexus Uterinus consists in a considerable number of veins, which are distributed upon the surface, and in the texture of the uterus ; they are also found in abundance in the broad ligaments, where they anastomose with the ovarial veins. The Plexus Vaginalis comes from the anterior parts of the organs of generation constituting the vulva, as the labia majora, minora, and so on. It also arises from the whole surface of the vagina, sur- rounds it completely, and anastomoses with the uterine veins. The Gluteal, the Obturator, and the Ilio-Lumbar Veins, also con- 26 * 298 CIRCULATORY SYSTEM. tribute to the Hypogastric. ; their description conforms so nearly to that of the corresponding arteries, that it is unnecessary to detail it. The Primitive Iliac Vein, (Vena Iliaca Primitiva , Communis ,) formed by the junction of the External and of the Internal Iliac, extends from the sacro-iliac symphysis to the lower margin of the fourth lumbar vertebra, where it joins the corresponding trunk of the opposite side of the body, to form the commencement of the ascending vena cava. In this course the left one passes obliquely across the body of the fifth lumbar vertebra, and beneath the right primitive iliac artery. The Vena Cava Inferior is situated on the front of the spinal co- lumn, to its right side, and extends from the lower part of the fourth lumbar vertebra ; or, in other words, from the junction of the primi- tive iliac veins to the under end of the right auricle of the heart, into which it empties. It is larger than the Descending Cava. In its ascent it inclines very gradually to the right side of the spine, so as to reach the opening in the tendinous centre of the dia- phragm, through which, it passes just before it terminates in the auricle. It is bounded on the left side by the aorta ; and above the latter it is in front of the left crus of the diaphragm. Its lower ex- tremity is crossed in, front by the root of the primitive iliac artery ; it is also crossed in its ascent by the duodenum and the pancreas. Its upper extremity is behind the liver, and frequently passes through the substance of this viscus. It receives the middle sacral, the lumbar, the spermatic, the emulgent, the capsular, the hepatic, and the phrenic veins. The Middle Sacral Vein (Vena Sacra Media) forms, as has been just mentioned in the account of the branches of the hypogastric vein, a part of the sacral plexus. Its trunk follows the course of the middle sacral artery on the front of the sacrum, and discharges into the commencement of the vena cava, in the fork formed by the junction of the primitive iliacs. The Lumbar Veins (Vence Lumbales ) correspond with the lumbar arteries, and are commonly four or five in number on. each side. Their primitive roots anastomose with the epigastric, the last inter- costal, and the circumflex iliac veins; the dorsal branches of them VEINS OF THE ABDOMEN. 299 also anastomose with the vertebral sinuses, through the intervertebral foramina. Their trunks pass along with the arteries, between the bodies of the vertebrae and the psoas magnus muscle, or through the fasciculi of the latter : those on the left side pass behind the aorta, in order to reach the vena cava, and are, consequently, longer than such as are on the right. The Spermatic Veins (Vence Spermaticce.) The right one extends from the testicle to the ascending cava, just below the emulgent veins; while the one on the left empties into the left emulgent vein. They are larger than the corresponding arteries, and present some peculiarities in the two sexes. In the male, the extremities of these veins begin in the testicle, and issue from it through the tunica albuginea ; some of them also arise from the epididymis. They anastomose with the superficial veins of the penis and of the scrotum, and disengaging themselves from the tunica vaginalis, at its back part, are assembled into four or five anastomosing trunks ; which envelop the vas deferens and the spermatic artery, and compose a principal part of the bulk of the chord. Having passed through the abdominal canal, they are reduced on each side to one trunk, which creeps along the sper- matic artery on the front of the psoas magnus muscle, and in com- pany with the ureter. Somewhat below 7 the kidney, the spermatic vein is again resolved into a sort of plexus, having frequent addi- tions from the veins, in the adipose substance of the kidney, and some also from the branches of the vena portarum in the mesentery, and in the mesocolon. It then is reduced once more into a single trunk, w T hich terminates as mentioned. The term Corpus Pampi- niforme (vine-like) is, by some anatomists, limited to the last plexus formed by each spermatic vein, but it is also frequently extended to both.* In the female, the spermatic vein is not so large as in the male ; it comes from the ovarium and from the side of the uterus, and is joined by some small branches from the round ligament of the uterus, and from the Fallopian tube. Passing outwardly between the laminre of the broad ligament of the uterus, it crosses the ex- ternal iliac artery, and in the subsequent part of its course is dis- posed of as in the male. * H. Cloquet, Trait. D’Anat. 300 CIRCULATORY SYSTEM. The Emulgent Veins ( Vents Emulgentes, Renales ) are commonly two in number, one on each side, and extend horizontally from the fissure of the kidneys to the ascending cava. They are of a con- siderable size, and owing to the position of the vena cava, the left is much longer than the right, and crosses in front of the aorta. They open on their respective sides of the cava opposite to each other. The branches of which the emulgent vein is composed, coming from the ramifications of the corresponding artery in the kidney, assemble into the single trunk near the fissure of the kidney ; this trunk is joined by some small veins from the adjacent adipose matter and from the capsule renales, and on the left side, as men- tioned, it is also joined by the spermatic vein. The Capsular Veins (Vents Capsulares ) arise from the arteries spent upon the capsulse renales ; and are two in number, one on each side. That on the right discharges into the vena cava, while the one on the left empties into the left emulgent most frequently. The Hepatic Veins ( Vents Hepaticce) take their rise in the liver, and collect into three principal trunks, which converging towards the ascending cava, discharge themselves into it, where it adheres to the posterior margin of the liver, immediately below the diaphragm. Two of these trunks come from the right lobe, and one from the left, moreover, there are several small hepatic veins wdrich dis- charge themselves into the cava, and come principally from the Lo- bulus Spigelii. The Inferior Phrenic Veins (Vents Phrenicte Inferiores) arise in the diaphragm, from the corresponding arteries. They are two in number, and discharge into the ascending cava just above the he- patic veins. SECT. V. — OF THE VENA PORTARUM. The Vena Portarum is derived from the viscera of the abdomen, and presents the singularity of a vein ramifying through a gland, the liver, before its blood is returned to the general circulation. The arteries from which it draws its supply of blood are the superior and the inferior mesenteric, and the cceliac with the exception of its he- VEINS OF THE ABDOMEN. 301 patic branch. The viscera of the abdomen, which contribute to it are the spleen, the gall-bladder, the pancreas, the stomach, the small and the large intestines, the large and the small omentum. a. The Splenic Vein ( Vena Splenica) is formed by several branches, which coming out separately from the fissure of the spleen, unite after a short course into a single trunk. This trunk runs in company with the splenic artery below it, along the superior margin of the pan- creas, it is not quite so tortuous as the artery itself, and proceeding from left to right, is joined to the superior mesenteric Vein in front of the vertebral column. In this course, the splenic receives the small veins,* ( Vents Breves ,) corresponding with the vasa brevia of the great end of the stomach, and then, successively, several branches from the pancreas. It like- wise receives the gastric, or the superior coronary vein of the sto- mach, the right gastro-epiploic, and the left gastro-epiploie of the same viscus, all of which correspond with the arteries distributed to the latter. b. The Inferior Mesenteric Vein ( Vena Meseraica Inferior ) corres- ponds with the inferior mesenteric artery, and, consequently, derives its primitive branches from the rectum by the upper hemorrhoidal veins, which anastomose wuth the lower ; from the sigmoid flexure of the colon ; and from the left descending portion of the latter. The trunk formed by these branches, ascends behind the perito- neum, between the left ureter and the aorta ; and going up behind the pancreas, is discharged into the splenic vein an inch or two from its termination. But, like the veins belonging to the lesser curvature, and the right side of the stomach, it sometimes empties directly into the vena portarum, or into the upper end of the superior mesenteric. c. The Superior Mesenteric Vein ( Vena Meseraica Superior ) is the largest of the trunks which contribute to form the vena portarum. It is derived from the ramifications of the superior mesenteric artery upon the small intestines, the ileo-colic valve, the right ascending and the transverse colon. Its branches constitute in the mesentery and the mesocolon a vascular intertexture, forming arches and meshes adhering to the corresponding ones of the arteries. In the transverse mesocolon, it, like the artery, anastomoses with the infe- rior mesenteric vein. Its trunk being formed by the union of these * M. Bauer discovered, in 1824, valves in these vessels, contrary to the general analogy of the system of the Vena Portarum. His observations have been confirmed by H. Cloquet. 302 CIRCULATORY SYSTEM. several branches, ascends the mesentery, and goes in front of the duodenum, where the latter crosses the spine; immediately after- wards it gets, behind the pancreas, and near its right end is joined by the splenic vein. It here, also, receives small branches from the duodenum, from the pylorus, and from the gall-bladder. The trunk of the Vena Portarum being formed behind the pan- creas by the union of the superior mesenteric with the splenic vein, extends from this point to the transverse fissure of the liver, and is about four inches in length. It ascends obliquely from left to right, behind the second curvature of the duodenum, being bounded on the right side by the biliary ducts, and on the left by the hepatic artery where it is surrounded by a great many nervous filaments and lymphatic vessels, with all of which it is united by a common envelope of cellular substance, and of Peritoneum, called the capsule of Glisson. Having reached the transverse fissure of tlie liver, it divides into two branches, which are each at a right angle to it, but in line with one another : they constitute the Sinus Portarum, of which the right branch being spent upon the great lobe, and the left upon the small lobe of the liver, are ramified almost to in- finity through the structure of the latter. The terminating branches of the vena portarum empty into the venae hepaticae. Several cases are recorded in the annals of anatomy in which the vena portarum, instead of going into the liver, discharged imme- diately into the ascending cava.* In such instances the hepatic artery is much larger than usual. According to J. F. Meckel, not- withstanding they are anomalies, yet, as in most other cases of de- viation from the general type of the human family, a striking analogy may be found between them and what occurs in some of the lower orders of animals. Here the analogy exists with the invertebrated animals. * Lieutaud, Hist. Anat. Med. Huber, Obs. Anat. p. 34. Abernethy, Ph. Tr. 1793, part. i. Lawrence, Med. Ch. Trans, vol. v. PECULIARITIES OF THE FCETUS. 303 CHAPTER IV. Of the Peculiarities iu the Circulatory System of the Foetus. Owing to the want of respiration in the foetus, its circulation is conducted in a manner very different from that of the adult. More- over, its parasitical life requires an alliance, through the organs of circulation, with the mother. Its peculiarities, therefore, may be studied under two heads : those which arise from the want of respi- ration, and those which are required for its nourishment. The pe- culiarities of the first order are situated in the thorax, and those of the second in the abdomen. SECT. I. — OF THE PECULIARITIES OF THE FCETUS, ARISING FROM THE WANT OF RESPIRATION. The Heart, at a very short period after conception, so early as about the end of the first month, is sufficiently developed to be in a state of great activity. The first indication of its existence, and, indeed, of the life of the new animal, is a small tremulous point, called the Punctum Saliens, from its incessant motion. The mus- cular structure of it is soon evolved, and in a few weeks becomes very manifest. At the earliest visible period of the heart in the incubated egg, which affords a satisfactory analogy, it consists of two vesicles united by a canal, (Canalis Auricularis of Haller.) One of the vesicles is the right auricle ; the other is the left ventricle, and is probably the first to pulsate. The aorta is also visible, as well as the venae cavae. The circulation, at this period, is very simple : the blood starting from the left ventricle, is propelled into the aorta ; it is collected from the ramifications of the last into the two venae cavae, and thereby brought to the right auricle; it is then propelled by the right auricle through the canalis auricularis into the left ven- tricle, whereby its round is completed, and it then starts again. This is the most simple kind of circulation, and is found, in fact, during the whole life of such animals as do not breathe by lungs ; 304 CIRCULATORY SYSTEM. for example, fish. As the gills in them take the place of lungs, a branch from the aorta, spent upon the gills, is sufficient for their purposes of respiration. The terms right auricle and left ventricle have been used, because the cavities alluded to perform the functions of the adult state ; but in the progress of the development of the heart, a partition begins to show itself which ultimately divides each of them into two distinct chambers, whereby we have a right auricle and a left one ; a left ventricle and a right one. And the canalis auricularis is reduced from a canal into a short orifice, called Ostium Venosum, commu- nicating from the auricles to the ventricles, and which is afterwards divided into two, one for either side of the heart. The partition be- tween the ventricles is completed about the end of the second month of gestation, at a period when the aorta, from having been simple originally, is converted into two canals, one of which be- comes the pulmonary artery. The partition between the auricles is not completed till birth. In cases of monstrosity, it is interesting to see how much the heart, at the end of uterine life, has still pre- served this original type of simplicity. I have formerly dissected a double foetus, where from the parasitical character of one, no effort had been made for the development of the lungs of the latter. The consequence of which was, the parasites heart consisted only of the right auricle and of the left ventricle, and the pulmonary artery had not been formed at all, there being but the single tube, the aorta, which led from the left ventricle, and had a sort of arrangement in its branches depending upon the tendency to form pulmonary arte- ries.* At birth, the auricular septum has advanced so far that the commu- nication between the two cavities is kept up only by a deficiency, called the Foramen Ovale. This foramen, marked by a depression on the right side, admits a small quill, when conducted obliquely through it, and is protected on the left side by a valve, the edge of which is upwards, and which when applied, is just large enough to cover the whole foramen. The moment that the blood ceases to pass through the foramen ovale, which occurs at the first act of in- spiration, the valve is applied, and the aperture grows up by the ad- hesion of its edge. The mechanism of this process is sufficiently simple. So long as the principal current of the blood was into the * For a detail of this case, See North American Medical and Surgical Journal, Philad., Oct., 1826. PECULIARITIES OF THE FCETUS. 305 right auricle, the valve was pushed off from the side of the septum ; but as breathing establishes, through the lungs, pulmonary veins, and left auricle, a current of circulation equivalent, both in quantity and force, to that through the two vense cavse and right auricle, a perfect equilibrium between the auricles is established, and the valve retains its place against the septum. Notwithstanding the incessant action of the auricles, during all the subsequent periods of life, this equilibrium, in the force and time of their contraction, remains uniform : a circumstance proved, conclusively, by the health and strength of adults in whom the valve has never adhered to the day of their death ; an observation made by many anatomists, and of which I have witnessed several examples. In one of them I passed two fingers readily from one auricle into the other, owing to the unusual size of the aperture. The valve which closes the foramen ovale is, first of all, scarcely perceptible; but as the foetus advances in age, the valve advances in size, and is indeed, large enough to close the foramen some weeks before birth. It is formed from the lining membrane of the two auricles, with an intermediate cellular substance. The Valve of Eustachius, which exists also in the adult heart, is placed at the anterior semi-circumference of the orifice of the ascend- ing vena cava in the right auricle, one of its ends adhering to the anterior margin of the foramen ovale. This valve, contrary to the one in the foramen ovale, is larger in proportion as the foetus is younger, and, when first observed, covers the whole orifice of the vena cava ascendens; its opening, however, is in the direction of the current of blood in the latter. It also is formed by a duplica- ture of the lining membrane of the auricle; and, from its disposition, determines the blood of the ascending cava to flow through the foramen ovale into the left auricle, either wholly or in part, accord- ing to the period of gestation. Its obliquity also gives a direction to the blood of the descending cava, into the right ventricle from the right auricle. These uses of the Eustachian valve were pointed out by the celebrated Sabatier;* their value will be illustrated here- after. The ventricles of the Heart, at birth, have the same structure and internal arrangement as afterwards; they are remarkable, how- * Traite d’Anat. vol. ii. p. 266. Vol. II.— 27 306 CIRCULATORY SYSTEM. ever, for being of equal thickness, or nearly so, an observation of Mr. John Hunter.* This fact is connected with the circumstance of their both contributing to the aortic circulation till respiration begins, owing to the pulmonary artery entering, during foetal life, by its largest branch, into the aorta. The Ductus Arteriosus constitutes this branch of the pulmonary artery, and is, in fact, the continuation of the trunk of the latter into the aorta, immediately behind the origin of the left subclavian artery. The right and the left pulmonary artery at this period, are but inconsiderable trunks, incapable by any means of carrying off all the blood of the right ventricle ; the greater part of it, therefore, is conveyed by the ductus arteriosus into the descending aorta. As the contraction of the ventricles, like that of the auricles, is synchro- nous, it is evident that the column of blood in the descending aorta, is acted upon by both ventricles at the same moment. The ductus arteriosus preserves the principle of a single circula- tion in the foetus, which was first of all manifested by the two ven- tricles, constituting but one cavity, and by the aorta and pulmonary artery being but one trunk. At the first act of inspiration the lungs, which were before solid, and the thorax, which was compressed, are greatly augmented in volume by the introduction of air. The dilatation of the thorax, besides introducing air through the trachea, causes an increased flow of blood through the right and left pulmo- nary arteries, in order to fill the vacuum in the lungs. The pulmo- nary arteries become in that way permanently dilated, and the cir- culation is finally drawn off entirely from the ductus arteriosus, though this takes several weeks or months before it is completely accomplished. The ductus arteriosus in this time is continually contracting, and is at length converted into a ligamentous chord, like other arteries, whose circulation has been arrested. These are the several peculiarities which distinguish the foetal circulation, owing to the privation of respiration; and it is clear, that the collective result is that of a circulation quite as simple as if the heart consisted of but two cavities; while, at the same time, it keeps this organ in a state of preparation for carrying on two dis- tinct circulations, one pulmonary and the other aortic, from the * Animal Economy. PECULIARITIES OF THE FCETUS. 307 moment that respiration begins: so that the whole mass of blood is, in subsequent life, brought successively under the influence of res- piration, by having to pass unavoidably through the lungs. SECT. II. — OF THE PECULIARITIES OF THE CIRCULATION OF THE FCETUS CONNECTED WITH ITS NOURISHMENT. The Umbilical Vein, one of the constituents of the umbilical chord, brings the blood from the placenta to the fcetus. This vessel is from three to four lines in diameter, and enters at the navel; thence it goes along the free margin of the suspensory ligament of the liver, and traverses the anterior half of the umbilical fissure, to terminate in the left branch of the sinus of the vena portarum. In this course through the liver, the umbilical vein sends off to the right and the left lobe, several small branches. As the intestinal circulation of the foetus is too small to send much blood through the vena portarum, it would be sufficiently correct to consider the sinus venae portarum as the bifurcation of the umbilical vein : but, as this might introduce a confusion into the description, it will be better to retain the adult nomenclature. The Ductus Venosus is a vein which occupies the posterior half of the umbilical fissure, and is about a line and a half in diameter. It arises from the left branch of the sinus portarum, opposite to the place where the umbilical vein entered or terminated, and is con- sequently in the same line with the latter. Traversing the posterior part of the umbilical fissure, it terminates in the left vena hepatica, as this hepatic vein is about joining the ascending cava, just be- low the tendinous centre of the diaphragm. Through this route much of the blood of the umbilical vein is carried directly to the right auricle of the heart, and then passed through the foramen ovale into the left auricle by the mechanism of the Eustachian valve. From these considerations, it is evident that the umbilical vein really performs the office of a vein till it reaches the liver, but that there, much of its blood is spent through the portal circulation, upon the structure of this viscus ; and that what remains is carried through the ductus venosus to the heart. Like other veins, it is furnished with 308 CIRCULATORY SYSTEM. valves, of which there are two ; one at its termination in the sinus portarum, and the other at the cardiac extremity of the ductus veno- sus.* The establishment of respiration, by putting the circulation into other channels, likewise causes its obliteration and final conver- sion into a ligamentous chord. The valve, at the sinus portarum, prevents the blood from taking a retrograde course, and thereby keep- ing the umbilical vein open ; the valve of the ductus venosus has the same effect upon the duct to which it belongs, and is aided by the current of blood in the left branch of the sinus portarum, setting across the mouth of the ductus venosus instead of plunging into it from the umbilical vein, as in foetal life. It is worthy of remark, that the left branch of the sinus portarum is bounded, on its right extremity, by the end of the vena portarum, and receives, about its middle, the umbilical vein. In the space, then, between the umbilical vein and the portal, the circulation, from the predominance of umbilical blood in foetal life, is conducted from left to right, but afterwards from right to left, as the portal cir- culation is established and the other is arrested. The Umbilical Arteries discharge the important office of conduct- ing the effete blood of the fcetus to the placenta. They are the con- tinuations of the internal iliacs, and are two in number, one on either side ; they conduct off so much of the blood of the primitive iliacs, as to leave the external iliacs of a very small size. During the early months of uterine life, they are rather, indeed, the continued trunks of the primitive i acs ; the branches from the latter being then so little developed as to appear quite subordinate to the chief function, of carrying the blood out of the fcetus, to the placenta. But as the inferior extremities and the buttocks grow, these subordinate branches are more and more evolved. At birth, the umbilical arteries, after dipping very superficially into the pelvis, rise up at the sides of the bladder and converge towards the navel. They emerge at the latter, cling together and traverse the umbilical chord by twisting spirally around the umbilical vein, like two small strings wound in this w r ay upon a larger one. Their diameter is from a line to a line and a half. They anastomose as they join the placenta, but not previously. Like the circulation between arteries and veins in other parts of the body, the capillaries of the umbilical arteries terminate in those * Bichat, Anat. Descrip, vol. v. p. 419. PECULIARITIES OF THE FCETUS. 309 of the umbilical vein in the placenta. From the observations of Wrisberg, Osiander and the highly distinguished Professor Chapman of the University of Pennsylvania, it seems that there is no direct vascular communication between the mother and the foetus. This opinion is founded upon the leading facts, that the finest injec- tions do not pass from one to the other ; that foetuses, after the death of the mother from haemorrhage, still live and retain their usual quantity of blood ; that if the foetus be expelled entire with the placenta and membranes unhurt, the circulation still continues. One example of which was witnessed nine minutes by Wrisberg;* another fifteen by Osiander ;f some from ten to twenty minutes by Professor Chap- man another for an hour by Professor Channing of Boston, and Dr. Selby of Tennessee, § where a bath of tepid water was used to resuscitate the foetus. Also, from the observations of Breschet, it seems that the globules of the blood of the foetus, when inspected by the microscope, are different in appearance from those of the mother. || Mascagni says that he has made several most minute injections of the pregnant uterus, so as to cover with small vessels its whole internal surface, and to return the injection by the uterine veins : and yet he has never succeeded in injecting, in that way, the secun- dines.^ I have, myself, repeatedly tried by minute injection to pass arti- cles from the foetal into the maternal vessels, and the reverse, but al- ways without success ; in two instances, the experiment was upon human subjects, and, in the others, on the cow. In one of the lat- ter, I perceived that some of the injecting matter thrown into the fcetal vessels had got into the uterine veins ; but as the observation was in opposition to all the others, and solitary, I have no disposi- tion to array it against them, at least, until farther and more decided experience. My second experiment on the human subject was made in April, 1833, under the following circumstances : A white female, aged 24, died at the Alms House, suddenly, and in the ninth month of pregnancy ; the foetus was still in utero, but the mem- branes were ruptured. In the presence of several of the physicians and students, and with the assistance of my young friend, Dr. God- * Meckel, Man. D’Anat. vol. iii. p. 163. f Id. f Chapman’s Med. and Phys. Journal, vol. i. p. 6. § Id. || Am. Med. Jour. vol. i. p. 193. H Prodromo, vol. i. p. 127. 27 * 310 CIRCULATORY SYSTEM. dard, to whose suggestions and manipulations I am indebted for the chemical compounds resorted to, I injected through the aorta one gallon of the saturated solution of Prussiate of potash, and followed it with an equal quantity of a saturated solution of sulphate of iron. The injection penetrated very minutely, as might be expected, and the precipitate of Prussian blue coloured deeply many parts of the skin. On dissecting the uterus, the uterine arteries were found well injected, but the injection did not reach the umbilical vein or arteries, as was proved both by simple inspection and by chemical tests. Having cut out the uterus and taken it to the University, the ex- periment Avas continued the next day in the presence of a large con- course of students and several physicians. The umbilical vessels were first of all injected with a saturated solution of bichromate of potash, and then with a saturated solution of sugar of lead. The result was a strong, yellow precipitate, the bichromate of lead. The injection passed reciprocally from the arteries into the vein, and from the vein into the arteries, conformably to the direction in which it was thrown for the time. The sinuses of the uterus were then injected with similar materials to those of the uterine arteries ; to wit, a solution of Prussiate of potash, followed by one of sulphate of iron. The umbilical vessels were then all filled with liquid plaster of Paris coloured yellow: and the uterine sinuses with liquid plaster of Paris coloured blue, of which they readily received eighteen ounces. A short time having been allowed for the setting of the injection, I cut into the substance of the uterus and of the placenta. No yellow injection was found in the vessels of the uterus, nor was there any blue injection found in the umbilical vessels of the placenta ; there Avas, therefore a deficiency of evidence of direct vascular communi- cation between the foetus and the mother. The placenta was infil- trated with Prussiate of iron, and considerable quantities of blue plaster were found in the cavity of the uterus. In the progress of the injection with the Prussiate of iron, into the uterine sinuses, the membranes were raised from the uterus in vesi- cations. The parts, having been distended and put aside to dry, at the end of a fortnight they were examined again by incisions, and the same evidence of the want of direct vascular communication was renewed. But the placenta was found to be infiltrated according to certain rules seeming to depend on its organization. The blue PECULIARITIES OF THE FCETUS. 311 colouring matter on the part of the uterus, and the yellow on the part of the foetus, determined in it two parts, one uterine and the other foetal, closely and alternately interlocked, like a dove-tailing : the uterine processes passed to within a short distance of the free surface of the placenta, while the foetal processes went almost to the base of the placenta. The confines of the two colours were defined well by this abrupt termination, the borders of these dove-tails. The appearance would, perhaps, be better designated by the terms uterine lobes, and foetal lobes, alternately penetrating, so as to constitute the whole mass of the placenta. No distinct vessel of a blue colour could, however, be seen in the uterine lobes ; but a few very spare yellow ones were visible. On raising up these uterine divisions, the orifices of the uterine sinuses were seen at their base. The inference from this experiment is, that though there is no direct connexion of blood vessels between the mother and the foetus, yet there is a part of the placenta which seems to hold a special connexion with the uterine sinuses, and which may possibly, therefore, by interstitial circulation, establish a connexion with the foetus. The facts are at any rate presented as they occurred. The effete blood of the umbilical arteries becomes regenerated in the placenta, assumes a brighter hue, and is returned to the foetus by the umbilical vein. According to the theory of Sabatier concerning the use of the Eustachian valve, if the latter did not exist, the fresh blood brought to the heart by the ductus venosus, instead of being diverted into the left auricle through the foramen ovale, would be received by the right auricle, and transmitted, either wholly or in a great degree, into the right ventricle. It would then be passed from the latter through the pulmonary artery and ductus arteriosus into the descending aorta, so that no part of the system, above the junction of the duct with the aorta, could receive the benefit of it : this would leave the head and upper extremities unsupplied with fresh blood. Moreover, much of the latter would be fruitlessly introduced, for it would depart almost immediately through the umbilical arteries. But the Eustachian valve determining the flow of blood of the ascending cava into the left auricle, its passage into the left ventricle is a matter of course : thence it begins the aortic circulation fairly, so that every part of the system participates in its benefits. The celebrated Wistar* has also happily suggested, that without * System of Anat. vol. ii. p. 76, 3d edition. 312 ABSORBENT SYSTEM. this arrangement, the blood of the coronary arteries of the heart itself, the purity of which is so essential to the vigour of circulation, would otherwise have been effete, and, consequently, unlit for its object of refreshing the heart. The umbilical arteries become the round ligaments of the blad- der, after the circulation through them has ceased, with the excep- tion of their pelvic extremities, which subsequently constitute the trunks of the Internal Iliac Arteries. CHAPTER V. Histology of the Absorbent System. The Absorbent System is one of the most interesting of those which compose the human body, both on account of its very gene- ral diffusion, and of the office of interstitial absorption that it inces- santly carries on, thereby removing the effete parts of the body and, making room for the deposite of new ones. It is also called the lymphatic system, owing to the transparent colour of the fluid which it conducts. With the exception of an imperfect observation of some of these vessels in the mesentery of a goat, by Herophilus and Erasistratus,. during the reigns of the Ptolemies in Egypt, 280 years before Christ, what is known of them is entirely a modern acquisition in anatomy. In 1564, Eustachius discovered the thoracic duct of a horse, which in the ignorance of its use, he called vena alba thoracis. This fact remained insulated and almost forgotten for seventy years. In 1622, Asellius discovered the absorbents of the mesentery, and in the dis- cussions consequent thereto, the original observation of Herophilus and Erasistratus was relieved from an oblivion of nineteen centuries, to be again brought to light and admired. Asellius seems to have understood that the absorbents of the mesentery collect the chyle from the intestines, but his knowledge ceased there, for he thought \ LYMPHATIC VESSELS. 313 that they discharged into the vena port arum.* In 1634, Weslingius saw the thoracic duct again ; and in 1649, ascertained that the chy- liferous vessels of Asellius terminated in it. In 1650, Olaus Rud- beck, a young man pursuing his anatomical studies in Leyden, saw first the lymphatic vessels of the liver, and in a few months after- wards injected similar ones in the loins, in the thorax, in the groins, and in the arm-pits. Thomas Bartholine, a teacher of great reputa- tion in those days, in a dissertation, dated in 1652, claimed for him- self the priority of these observations, and from the obscurity of Rudbeck, enjoyed for some time the merit of them. In 1654, Rudbeck published and set forth his own pretensions with such force, that he finally triumphed over his antagonist, but not until the whole world of anatomy had been set in commotion ; one party being for the professor, and the other for the pupil, and many bloody strifes having arisen between the students of the respective sides. In 1653, Jolyff, a celebrated anatomist, of London, proclaimed his own rights to this w T armly contested honour ; but the period being rather late, his name is scarcely associated with the history of these feuds. Almost a century then passed before there were many im- portant additions to the knowledge of those times. After which great contributions were made by Dr. A. Monro, f Dr. W. Hunter , X Hewson,§ and Cruikshank,|| but chiefly by the celebrated Mascagni, IT who, having imagined finely pointed instruments of glass for exe- cuting his injections of these vessels, succeeded in demonstrating them in almost every part of the body, excepting the spinal marrow, the brain, the ball of the eye, and perhaps the placenta. In some of these parts, however, he says he has seen them, and he speaks con- fidently of their existence, without exception, every where, even in the enamel of the teeth.** The Lymphatic Vessels are small, pellucid, transparent, cylin- * It is somewhat remarkable, that the celebrated Harvey, who had himself so much to complain of, in the obstinacy with which his cotemporaries adhered to ancient errors, for thirty years resisted the discovery of Asellius, and died, finally protesting against it. f He Yenis Lymphat. Valv. Berlin, 1757-70. X Med. Comment. London, 1762-77. § Experimental Inquiries, London, 1774-77. || Anat. of the Lymphatics, London, 1774-90. If Vasor. Lymph. Corp. Hum. Historia et Ichnographia. Sienna. 1787. ** Prodromo della Grande Anatomia, vol. i. p. 1. 314 ABSORBENT SYSTEM. drical tubes, generally of about a line or less in diameter, whose trunks have been traced to all the external and internal surfaces of the body, and to the depth of all the organs, with the exceptions stated. It is only lately, however, that their existence on the ex- ternal surface of the skin has been put beyond doubt, by the ob- servations and injections of M. Lauth.* Their origin is so attenu- ated, that anatomists have come to no satisfactory conclusion in regard to its manner. The visible origin of the absorbents is, in some 'parts, as in the intestinal canal and on the glans penis, according to Breschet, as a reticulated intertexture, the meshes of which are so close as to leave scarcely an interval between them. In the peritoneal coat of the liver this reticulation is so fine and close that the membrane appears to be composed wholly of them : their connexion, however, with the deeper absorbents is so free that they cannot be preserved in this state owing to the subsidence of the injection, especially if it be mercury. Professor Fohman, of Heidelberg, whose injections are said to be of a most superior kind, is of opinion that in many cases these vessels have a cellular origin, such at least is the appearance of those in the cornea and in the umbilical chord injected by him. Muller, however, doubts the accuracy of his conclusions in regard to the character of these cells. f Fohman is indeed of opinion that cellular substance consists merely of lymphatics. The earlier cultivators of this branch of study, not knowing their absorbent properties, conceived them to be continuations of the arte- ries applied to the reconducting of the serous part of the blood to the heart ; and considered the opinion substantiated by the circum- stance of their being occasionally filled by fine injections thrown into the arteries. More improved views of their uses caused the abandonment of this theory, and the substitution of their absorbing powers ; in w T hich case the minds of anatomists became divided be- tween the ampulla-like mouth, or wide patulous origin of Lieber- kuhn, and the small orifices of Hewson. It is, perhaps, not possible to solve the question in regard to the mode of origin of the lymphatics, at least, in most parts of the body. Meckel, about the middle of the last century, asserted their conti- nuity with the veins. Mr. Ribes has seen matter injected into the vena portarum find its way into the lymphatics of the liver. On * Essai sur les Vaisseaux Lymph. Strasburg, 1824. f Loc. cit. p. 283. LYMPHATIC VESSELS. 315 this subject, M. Chaussier says,* that, ignorant of the manner in which the arteries, veins, nerves, and lymphatics, arrange them- selves collectively into a glandular structure, or, in other words, into a capillary system, we cannot avoid ignorance of the part acted by the lymphatics alone ; we only know that the minute lymphatics form a portion of the elements of each viscus and structure of the body, and that they only become visible in becoming larger trunks. The absorbents in proceeding from their origins, in general be- come larger and less numerous, and form frequent anastomoses with one another. The proportionate increase of magnitude from the successive junction of trunks is by no means equal to what oc- curs in the veins. The larger superficial absorbent trunks of the extremities have not so much disposition to run into one another, hence they retain a size almost uniform from one end of the limb to the other. When fully distended, the appearance of absorbents is not regularly cylindrical, but knotted, owing to the frequent valvular interruptions in their cavities. The absorbents from all parts of the body, are finally united into two tubes ; one on the left, and the other on the right side of the trunk of the body, and which dis- charge their contents into the venous system, each on its respective side, at the junction of the internal jugular and the subclavian vein. The trunk on the right side receives the lymphatics of the right side of the head and neck, of the right lung, and right superior extremity ; while the trunk on the left, called the thoracic duct, receives all the chyliferous vessels and the lymphatics of the remaining part of the body. It would appear, from the observations of the younger Lauth,f that there are also other terminations of the lymphatics in the veins ; to wit, such as in the } r et capillary state end in the veins of the minute structure of organs, and such as empty into them in the interior of the lymphatic glands. Previously to Lauth, this senti- ment of communication with the veins was strongly advocated by several anatomists and physiologists, for the following reasons: 1. That the known roots of the lymphatic system have an area much superior to that of the trunks in which they terminate. 2. That substances introduced into certain lymphatics by absorption or in- jection, have been found in the contiguous veins. 3. That a liga- ture upon the thoracic duct produced death only after ten or fifteen days, and then the articles which had been absorbed by the intestines, * Diet, des Sciences Med. Art. Lymphatiques. ^ f Loc. cit. 316 ABSORBENT SYSTEM. were found in the blood. 4. And that injections had proved this communication. Notwithstanding the well known fact of injections, under certain circumstances, passing from the arteries into the lymphatics, some anatomists of modern date have hesitated in admitting a direct communication. M. Meckel has, indeed, rejected the notion en- tirely, on the ground that the fluid contained in the trunks of the absorbents is always the same as one finds at their commencement. For example, the lymphatics coming from the liver contain a fluid like bile; those which come from the mammae contain a fluid like milk; those which come from parts suffering from an extravasation of blood contain a sanguineous fluid; the bronchial glands are coloured by the black pigment brought to them from the lungs ; poisonous matter, as that of the small-pox or venereal, irritates and inflames the lymphatics that lie in the course of its introduction into the system. For these reasons it would appear to him, that the arteries do not continue themselves into the lymphatics as they do into the veins. The observations of M. Lauth seem to have proved the point, that some of the lymphatics take their origin from the in- ternal surface of the arteries; and it may be through them that in- jections have been forced from one system into the other. In the case of the liver of a child, I have injected its absorbents very successfully from the arteries. The coats of the lymphatics generally are too thin and transparent for an investigation of their structure ; but as those of the thoracic duct are sufficiently thick for the purpose, one may estimate the structure of other trunks by it. It is thus ascertained that they consist of tw T o coats, an internal and an external one.* The external coat is somewhat irregular on its surface, from its connexion with the adjacent cellular substance; and has a filamen- tous appearance more deeply, which has been considered as fibrous, or muscular, by some anatomists, owing to its contraction upon the application of certain stimulants. The internal membrane is ex- tremely fine and perfectly transparent, and is remarkable for its fre- quent duplications, whereby a system of valves is produced re- sembling those of the veins. These valves are generally of a semi-lunar or parabolic shape, and are arranged in pairs, though according to Lauth, f some of them are circular, and do not close * Valentin asserts that there is also a middle coat, and Henle that there is an internal epithelium. f Loc. cit. LYMPHATIC VESSELS. 317 the canal entirely. The pairs are not placed at stated distances from one another, but vary in different parts of the body ; in some places there are several in the course of an inch, and in others not one pair. As a general rule, they are less frequent as the trunk increases in magnitude; hence, the thoracic duct has but very few of them. The valves, by having their semi-circumference fixed, while the diameter is loose and inclined in the course of the circu- lation, prevent the retrograde movement of the contained fluid. An enlargement of the trunk at their outer face into sinuses, resembling those at the valves of the veins, gives also to the lymphatic trunk a knotted condition when it is fully injected. The coats of the lymphatic vessels, though very thin, are yet dense and extremely strong, much more in proportion than those of any other tubes. They are both extensible and elastic, possess striking powers of spontaneous contraction in the living body, and also contract in the dead, but to a less extent. They are furnished with arteries and veins, and probably with nerves also, from their sen- sibility in a state of inflammation. And, as they stand in need of a similar organization with other canals, their parietes are said also to have lymphatics. The absorbent vessels, are, by some, divided into lacteals and lymphatics,* the first term expressing those which convey the chyle from the intestines, and the second such as are found in other parts of the system. As the difference is more in the fluid conducted than in the structure of the vessels themselves, the division is rather superfluous. There is also a distinction of the lymphatics, as in the veins, arising from their situation; some of them are called su- perficial, and the others deep-seated. The arrangement upon which this nomenclature depends, is found in the head, trunk, extremities, and in most of the viscera. The deep-seated trunks are the largest. They are the least numerous in the muscular parts of the body. * This division has been handed down from the time of Bartholine, who, not, suspecting- the absorbing powers of the lymphatics, held them only as organs of circulation for restoring to the heart the serum of the blood. The sagacious mind of Dr. W. Hunter first imagined their absorbing powers, and established the theory of their identity of function, in this respect, with the lacteals. The priority of the theory was warmly contested for Dr. Monro, of Edinburgh. Vol. II.— 28 318 ABSORBENT SYSTEM. Of the Lymphatic Glands. The Lymphatic or Absorbent Glands or Ganglions, sometimes called waxen kernels in common language, are an appendage of a very important description to the absorbent system. They are flat- tened ovoidal bodies, of a reddish ash colour, indurated so as to af- ford a strong resistance to pressure, and of a variable volume, from a line to twelve lines in their long diameter. They are found prin- cipally in clusters or chains, and are more abundant in the neck, in tire groin, in the arm-pit, in the mesentery, and about the bifurcation of the trachea. The lymphatic vessels, in their course towards the thoracic duct, have to pass through one or more of these glands. This rule is almost universal ; some exceptions, however, to it, in the case of the lower extremities, have been stated by Mr. Hewson, and in the case of the back, by Mr. Cruikshank :* the latter believes Mr. H. to have been under a misapprehension in this statement concerning the extremities, as it had not been verified by the result of his own in- vestigations. The vessels mat enter into the glands are called vasa inferentia, while those that depart from them are the vasa efferentia. As, owing to the juxtaposition of many of these glands, the vessels between them are very short, this distinction would likewise seem almost superfluous, because there is scarcely space to apply the term efferentia, before the same vessels enter the consecutive gland, thereby becoming inferentia. For the most part, the vasa inferentia are more numerous and somewhat smaller than the efferentia. The former, as they enter the gland, radiate into smaller branches, while the latter are formed from the junction of smaller branches. Each lymphatic gland is surrounded by a capsule, resembling- condensed cellular substance, which adheres very closely to the gland, and from which cause many anatomists are disposed to deny its existence, at least as a distinct membrane. They are also abun- dantly furnished with arteries and with veins destitute of valves ; but though they are penetrated by nervous filaments, it is not yet satisfactorily ascertained that any remain with them ; it is, however, more probable than otherwise. Their connexion with the surround^ * Anat. of Absorb. Vessels, second edit. p. 79. London, 1790. LYMPHATIC GLANDS. 319 ing cellular substance is sufficiently loose to permit them, in certain parts, to be slid moderately backwards and forwards. When this motion is arrested, it is from inflammation about them. The capsule of the lymphatic gland, like that of other glands, sends processes within to keep its parts together, and to conduct the blood vessels. It also contains a peculiar fluid called, by Haller, succus proprius, which is principally found in young animals, di-. minishes as they advance in age, and finally disappears. It is of various colours, but more frequently white ; it appears to have globu- lar particles in it, which (he late Mr. Hewson, for divers reasons, thought to become afterwards the red globules of blood. When a lymphatic gland is injected with quicksilver, it appears to be made up by the minute branching of the vasa inferentia, and the roots of the vasa efferentia, the former being continued into the latter. There is also some appearance of small cells intermediate to these two orders of vessels. All anatomists admit the former opinion ; but many reject the latter, under a presumption that the appearance is delusive. The arguments seem to be in favour of their existence. Mr. Cruikshank,* whose address in these matters was certainly of the first order, declares that he never failed to per- ceive them, and particularly well, just as the mercury was entering the gland. This arrangement is still more readily made out in ani- mals, as the horse, ass, mule. It also seems, from his observations, that when there are more than one vas inferens and efferens, there are cells for each set, which are kept distinct from the cells of the others, though they communicate freely with their cognates. Mr. Aber- nethy’s investigations, on the mesenteric glands of whales, coincide with the views of Mr. Cruikshank : he states, indeed, the cells as being large spherical bags, into which the lacteals plainly open. The celebrated Mascagni also acknowledges, and, in fact, describes the cellular structure of these glands, f which he had ascertained both by quicksilver and by wax injections. The improved notions of modern anatomy, upon what is called the erectile tissue, that is, the cells intermediate to arteries and veins, as in the penis and other places, and now considered rather as the dilated extremities of vessels, would also assist in warranting the opinion advocated. The celebrated Ruysch thought that he had discovered acini in the lymphatic glands, and sent his injected preparations illustrative of # Loc cit. p. 15, pi. iii. f Vasor. Lymph. HisL 320 ABSORBENT SYSTEM. them to Boerhaave. Some idea of the enthusiasm of the anatomists of old may be conceived by his saying “ Quando jam clarius et per- fect ius videbam hrec omnia, prse gaudio exsiliebam.” When the absorbing powers of the lymphatics had been esta- blished by Dr. W. Hunter, they were for a long time considered as the exclusive functionaries in this operation; and the opinions pre- viously entertained had sunk into such disrepute, from some expe- riments of Mr. John Hunter,* * * § that they were considered rather as food for literary research and curiosity, than for deliberate adoption. In the year 1809, M. Magendie reported his experiments on absorp- tion, which seemed to favour the notion that the veins also assisted in this office, a theory as ancient as Galen. The more recent ob- servations of Fohman, in 1821, and Lauth, in 1824, on the com- munications of the lymphatics with the veins, in the midst of the tissues of organs, and in the lymphatic glands, seem now to explain away again the theories of the absorbing powers of the veins, and to reinstate the lymphatics in their reputed exclusive functions. It is also stated that an anatomist of Florence, M. Lippi, has still more lately found several large lymphatic trunks entering into the ascend- ing cava. The connexion of the lymphatic system with the vena cava ascendens, and also with the external iliac veins has been farther demonstrated by certain preparations, exhibited by M. Amussat to the Academic Royale.f M. Fodera has, however, again brought the subject under discussion, by multiplying the active agents of this function, and says, that his experiments prove that all organized tissues enjoy it, and not certain parts only, as has been heretofore supposed from which it results that most of the rules in regard to the application of local remedies are inexact, and that we should have more regard to the thickness and density of tissues, to the quantity and rapidity of their circulation, than to simple locality. § * Med. Commentaries. f Am. Med. Jour. vol. i. p. 422. £ Reclierclies Experimentales sur 1 ’Absorption et l’Exhalation. Paris, 1824. § For a most interesting and instructive series of experiments on the laws and phenomena of absorption, see Philadelphia Journal of the Medical and Physical Sciences. Nos. 6 and 10. The experiments were executed by Drs. Lawrence, 13. H. Coates, and Richard Harlan, of this city. ABSORBENTS OF THE HEAD AND NECK. 321 CHAPTER VI. Of the Special Anatomy of the Absorbent System. SECT. I. — OF THE ABSORBENTS OF THE HEAD AND NECK. The Superficial Absorbents of the head are found in company with the several branches of the temporal, the occipital, the frontal, and the facial arteries, and, in order to get into the lymphatic trunks leading to the thoracic duct, follow or rather reverse the course of their respective arteries. There are at least two absorbent trunks for one arterial, and frequently more : those on the face are more abundant than such as are on the side of the cranium, owing to the excess of cellular substance on the former. The absorbents of these two regions anastomose freely beneath the external ear, between the skin and the parotid gland. The Deep-Seated Absorbents of the head have been followed to the membranes of the brain, but not farther. Ruysch observed them between the tunica arachnoidea and the pia mater, inflated with air, and called them vasa pseudo-lymphatica. Lancisius, Pacchioni, and others, assert their having found them in the pia mater. Doubts are cast upon these several observations, owing to such vessels not having been injected with quicksilver, and from the want of a valvular appearance in them ; also from the want of lymphatic glands in the cavity for the brain. Their existence, would seem to be sufficiently proved, both from general analogy, and from affections of the brain producing swellings in the glands of the neck. On the dura mater they have been traced along the course of its arteries. They descend from the interior of the cranium into the neck, along the carolid and vertebral arteries. The absence of lymphatic glands in the cranium may be accounted for from the fact, that the ready tendency of these organs to swell upon slight causes of irritation, would have rendered the individual liable to death, from compression of the brain, by their tumefaction. Mr. Cruikshank considers himself to have found lymphatic glands in ths' carotid canal. 28 * 322 ABSORBENT SYSTEM. The Deep Lymphatics of the face, as those from the interior of the nose, of the orbit, of the tongue and mouth, attend the arteries which respectively supply those parts. These several absorbents, from the surface and from the interior of the head, descend to the base of the cranium, and then begin to pass through the chain of lymphatic glands situated along the course of the great blood vessels of the neck. They lie, for the most part, under the sterno- mastoid muscle, and, when successfully injected, are thought to form the most brilliant plexus of absorbents in the whole frame. On each side of the neck, one or more common trunks are, at length, formed; that on the left side joins the Left Thoracic Duct near its termination, while the one on the right assists in forming the duct peculiar to that side, the Right Thoracic Duct, or, more properly called, the right Brachio Cephalic. The lymphatic vessels of the muscles of the neck, and those of the thyroid gland, enter into the trunks of the neck. According to Mr. Cruikshank, those of the thyroid gland may be readily injected by plunging a lancet at random into its substance, and then introducing air or quicksilver. Of the Absorbent Glands of the Head and JYeck. The only claim of lymphatic glands to an existence in the cavity of the cranium, is founded upon the supposition that the Pineal, the Pituitary, and Pacchioni’s Glands are of this character; but it is far from being established, and there seems indeed to be some doubt whether the glands found in the carotid canal, by Mr. Cruikshank, are not the carotid ganglion of the Sympathetic, noticed by Lau- monier. On the external surface of the cranium, over the insertion of the sterno-mastoid muscle, there are from four to six of a small volume ; on the face there is one or more small ones, below the zygoma, and from two to four on the external surface of the parotid ; there is one or more small ones situated in the substance of the parotid gland, which according to Burns, are generally the seat of tumours falsely attributed to the parotid itself. There are also some small glands along the facial artery as it ascends from the base of the jaw to the corner of the mouth. On the neck there are two or more small glands, immediately, ABSORBENTS OF THE HEAD AND NECK. 323 under the skin of the symphysis of the jaw, and eight or nine around the submaxillary gland. The most numerous congeries of glands on the neck is, along its great blood vessels, and covered more or less by the sterno-mastoid muscle, being principally between its posterior margin and the anterior of the trapezius. Along the latter line there are about twenty, in addition to six just above the superior margin of the clavicle. On the trachea, just above the sternum, there are four, forming the upper end of a series which descends along the oesophagus and trachea to the root of the lungs. SECT. II. — OF THE ABSORBENTS OF THE UPPER EXTREMITIES AND OF THE CONTIGUOUS PARTS OF THE TRUNK OF THE BODY.'*' The superficial absorbents of the upper extremities are very nu- merous, and lie between the skin and aponeurosis. They begin at the ends of the fingers and thumb; there being two or more branches for each, both before and behind. The posterior branches pass to the back of the hand and of the fore-arm : some of them, more espe- cially those from about the thumb, run up along the radial side of the fore-arm to the bend of the arm ; but by far the greater part of them incline very gradually in a semi-spiral manner towards the ulna, and then to the front of the fore-arm. Such of the superficial vessels as come from the front of the fin- gers and hand, continue to ascend straight up the fore-arm to its bend. These vessels of the fore-arm are so numerous that for every few lines there is an ascending trunk on its circumference : some of them coalesce, others form plexuses, and their number is much re- duced at the elbow. From the elbow the superficial lymphatics ascend to the axilla in fifteen or twenty parallel trunks, along the internal margin and the front surface of the biceps flexor cubiti. The outer side of the arm has comparatively but few absorbent trunks upon it, but some follow the course of the cephalic vein, penetrate with it into the axilla, and, then join the inferior lymphatics of the neck. The Deep Absorbents of the upper extremity attend the arteries.. * Anat. Atlas, Figs. 498, 499., 324 ABSORBENT SYSTEM. and are at least two for each principal artery. They anastomose with the superficial ones at intervals, and at last terminate in the axillary glands. As they follow strictly the course of the- arteries, a farther specification is needless. The Superficial Absorbents of the contiguous portions of the trunk of the body are not by any means so numerous as those of the upper extremity ; they consequently are more distant from one another, and they also go along in a more serpentine manner. From the nape of the neck to the lower part of the loins they all converge to tire arm-pit. The absorbents which are situated on the front of the pectoralis major muscle, and those on the side of the body from the arm-pit to the hip, also converge to the axilla. In regard to the two latter places, some of their absorbents, by penetrating the pa- rietes of the thorax or abdomen, respectively join the internal ab- sorbent trunk of thes£ cavities. These several lymphatics from the upper extremity and from the trunk, traverse the axillary glands, and are successively reduced in number to four or five voluminous trunks, which' surround the sub- clavian artery. While in the axilla they are re-enforced by the deep lymphatics from beneath the pectoralis major, the latissimus dorsi, and the shoulder. Their number being again reduced, they go along the subclavian vein over the first rib ; those of the left side open either into the thoracic duct at its termination, or into the subclavian vein, near it : but those on the right are finally assembled into the single large trunk, brachio-cephalic, which discharges into the angle of junction of the right internal jugular and subclavian vein. Absorbent Glands of the Upper Extremity. These glands are rarely found on the fore-arm, but when they do exist, it is in the course of the deep absorbents, and they are very small, and but few. From one to four are found scattered on the front of the elbow and internal condyle. From four to seven exist along the sheath of the brachial vessels and nerves. The axillary glands are very numerous, and of different sizes; they are dispersed throughout the cellular substance of the. axilla, reposing on the serratus major anticus, between the pectoral muscles and those of the shoulder, and being for the most part, below the ABSORBENTS OF THE INFERIOR EXTREMITIES, 325 axillary vessels and nerves, but some reposing immediately upon them, and forming a chain from the lower part of the axilla to the clavicle. Their number is from fifteen to thirty-five or forty. All the absorbents which observe the route of the axilla to reach the thoracic duct have to pass through these glands. SECT. III. — ABSORBENTS OF THE INFERIOR EXTREMITIES, AND OF THE CONTIGUOUS PARTS OF THE TRUNK OF THE BODY.* The superficial absorbents, like those of the upper extremities, are placed between the skin and the aponeurosis, in the cellular tissue that contains the subcutaneous veins. They are also very abundant, and are found every few lines on the' circumference of the limb ; they are, however, more numerous internally than externally, and, for the most part, run upwards. Those on the inner or anterior side of the limb are first perceived on the back of the toes and foot. They incline aver the front of the ankle, and its internal face, to the inner side of the leg; they then ascend over the inner side of the knee, and along the same side of the thigh to the groin. The superficial absorbents of the back of the lower extremity are first perceived on the sole of the foot. They ascend along the back of the outer ankle and of the leg above the knee ; they then incline semi-spirally inwards, so as to bring them- selves to the front of the thigh. These several absorbents, though there are but few on the foot, augment continually in number by new accessions in their ascent. All those on the posterior internal face of the thigh wind over its internal side, while such as are on its posterior external face wind over the outer side, to reach the in- guinal glands. The Deep Absorbents adhere to the arteries, being at least two to each, and adopting the same distribution and nomenclature. The anterior tibial set begins in the sole of the foot, and rises to its back between the first two metatarsal bones ; another branch begins * Anat. Atlas, Figs. 503 to 507, inclusive. 326 ABSORBENT SYSTEM. on the dorsum of the foot. The first pursues the course of the an- terior tibial artery through the interosseal ligament to the ham, the second frequently joins the peroneal absorbents about half way up the leg. The posterior tibial and the peroneal absorbents, as they cruise along their respective arteries, do not require any farther com- ment. There is a fourth set of these deep absorbents, amounting to two or three in number, which attend the external saphena vein, and come from the external side of the foot. Getting between the heads of the gastrocnemii muscles, they are re-enforced by other trunks from this muscle ; some of the branches then associate themselves with the superficial lymphatics, and others penetrate the ham, so as to join the deep trunks there. The deep absorbents of the leg coalesce partially in the ham, and ascend along the popliteal artery. On the thigh, there are from four to eight of these trunks attending the femoral artery, and receiving additions as the latter detaches branches. There are two or three lymphatic vessels on each side of the penis, which begin at its glans and prepuce, and traversing the length of this organ, wind above the external abdominal ring to join tire nearest inguinal gland. There are several from the side of the scrotum and perineum, which ascend along the chord and thigh to join also the nearest inguinal gland. In the female, those of the labia externa and clitoris correspond with those of the scrotum and penis. The superficial absorbent trunks, from the lower front of the ab- domen, are not numerous ; they descend and converge also to the inguinal glands. Some of those from the loins, such as do not as- cend to the axilla, advance to the inguinal glands. Those of the buttocks do the same. Absorbent Glands of the Lower Extremities Absorbent Glands, below the knee, are not abundant, or indeed, veiy common ; yet, one or two exist sometimes in the course of the anterior tibial artery in the upper part of the leg. The popliteal glands are three or four; they are small, and scattered at wide inter- vals in the fat of the ham around its vessels. From the latter to th$ groin, they are not usually found at all. The Inguinal Glands are amongst the largest in the system ; they DEEP ABSORBENTS OF THE PELVIS. 327 repose along the anterior margin of Poupart’s ligament and a little below, and are readily felt beneath the skin. The superficial vary in number, in different individuals, from seven to twenty, being more numerous as they are smaller, and are placed between the la- minae of the fascia superficialis. They receive first of all, the super- ficial lymphatics of all the parts mentioned. The deep-seated are smaller, are a little lower down on the thigh, and lie along the course of the femoral artery, beneath the aponeurosis of the thigh ; they are from three to seven in number, but are much less constant than the superficial. SECT. IV. — DEEP ABSORBENTS OF THE PELVIS.* The Deep Absorbents of the parietes of the pelvis, as in other cases, attend the arteries of the part and have the same names. The obturators come from the heads of the adductor muscles, and pass- ing through the obturator foramen, end in the hypogastric glands. The ischiatics come from the small muscles on the back of the hip joint, and getting into the pelvis along with the ischiatic artery, they also terminate in the hypogastric glands. The gluteals come from the three gluteal muscles, and entering the pelvis along with the artery at the superior margin of the sciatic notch, they likewise ter- minate in the hypogastric glands along with some vessels from the anus and the perineum. The ileo-lumbar, the sacral, and the cir- cumflex iliac absorbents, also follow their respective arteries and terminate in the nearest glands. The absorbents of the Testicle are numerous and large: accord- ing to Dr. W. Hunter,! they can sometimes be very completely injected by a pipe thrust into the substance of the testicle, and, according to Cruikshank,j: very advantageously from the vas defe- rens, which has succeeded in my own hands. They form two layers, one superficial coming from the tunica vaginalis testis, and the other from the substance of the gland. They, finally unite, into some six or eight trunks, which§ ascend with the chord through the abdominal canal. Occasionally one or more of them is as large as a crow-quill. By following the course of the spermatic artery, they at last terminate in the lumbar glands. * Anat. Atlas, Fig. 500. f Loc. cit. p. 155. f Loc. cit. § Mascagni, loc. cit. 32S ABSORBENT SYSTEM. The deep absorbents of the Penis accompany the arteries, and, therefore, either get into the pelvis beneath the symphysis of the pubes, or along the crura and the tuberosities of the ischia ; hence, a chancre on the prepuce causes bubo, while one on the glans very rarely does, and yet the constitution will be equally affected.* These absorbents terminate in the hypogastric glands. The deep absorbents of the Clitoris follow, in the same way, the internal pudic artery. The absorbents of the Urinary Bladder are also numerous, and pass in several trunks from its sides to the hypogastric glands. Those of the prostate gland and vesicular seminales are associated with them. The absorbents of the lower part of the vagina accompany the round ligament of the uterus through the abdominal canal, and, finally anastomose with those of the uterus. Those of the upper portion of the vagina are immediately associated with such as be- long to the uterus. The absorbents of the uterus are not so well seen in the unim- pregnated state, but in impregnation they are so prodigiously nume- rous that when injected with quicksilver, one is almost tempted to suppose that the uterus consists entirely of them. Mascagni’s plate on this subject is an exquisite specimen.! As they all terminate in the hypogastric trunks, the latter are in such case as large as goose- quills.:]: The hypogastric plexus, from these several accessions from the parietes and viscera of the pelvis, becomes very large, and follows the course of the hypogastric artery in ascending into the loins. There are likewise some spermatic absorbents in the female, called so from attending the vessels of the same name. They come from the ovarium, the Fallopian tube, and the round ligament, to terminate in the lumbar glands : they anastomose below with those of the uterus. Of the Glands of the Pelvis. Some few glands lie beneath the gluteus magnus muscle, but the majority are within the pelvis. Those which are called the Ex- ternal Iliac are at least six, frequently more, and extend from Pou- * Cruikshank, loc. cit. f Loc. cit. % Cruikshank, loc. cit. ABSORBENTS OF THE ORGANS OF DIGESTION. 329 part’s Ligament to the lower part of the loins, being planted along the external iliac artery, both above and below. The Hypogastric or Internal Iliac Glands are rather more numerous than the others, and form a chain along the hypogastric artery. They are much disposed to form large indurated masses from diseases of the rec- tum, uterus, and bladder.* SECT. V. — ABSORBENTS OF THE ORGANS OF DIGESTION, f The Absorbents of the Stomach are very numerous, and lie in two planes: one is superficial, being immediately beneath the peri- toneal coat, and the other is profound being placed between the muscular and the mucous coat. They are, finally, assembled into three divisions, which follow the course of the principal blood ves- sels of this organ. One division coming from the anterior and the posterior face of the stomach, converges to its lesser curvature, and passes through some six or eight small glands in the adjacent portion of the lesser omentum. Inclining to the right of the cardiac orifice, its trunks then pass through some glands common to them and to the deep lymphatics of the liver. Their numbers being reduced, they then descend behind the pancreas, and terminate in the thoracic duct near the cceliac artery. The second division comes from the left inferior portion of the stomach, and from its greater extremity, and, blending with the ab- sorbents of the spleen and pancreas, goes with them into the tho- racic duct. The third division comes from the right inferior portion of the stomach, and, assembling towards the pylorus, is subsequently mixed with some of the absorbents of the liver and of the small in- testines, and goes along with them into the thoracic duct. The Absorbents of the Great Omentum join those of the stomach and of the colon, at the points most -convenient to them. The Absorbents of the Small Intestines,, like those of the stomach, are both superficial and deep, and from the function of conveying * Cruikshank, loc. cit, Ij- Anat. Atlas, Figs. 501, 505. Vol. II.— 29 330 ABSORBENT SYSTEM. chyle, have been called lacteals, or chyliferous vessels. As the chyle, however, can only be absorbed by the deep ones : as they and the superficial have common trunks, and as they also absorb, from the intestines, fluids not converted into chyle ; there seems to be no necessity for distinguishing them by a particular epithet. The deep are in the cellular coat of the intestine, and follow the ramifi- cations of the arteries, being double their number. The superficial, being immediately beneath the peritoneal coat, run for some distance, longitudinally, on the gut, and then turn off to the mesentery at right angles. On the mesentery these absorbents are not rigidly bound to the course of the blood vessels ; they converge in a slightly tortuous manner from its circumference to its root. They anastomose with one another, by which their number is reduced; and they also have to pass through the series of mesenteric glands. The lacteals of the duodenum and jejunum are larger and more numerous than those of the ileum, in the proportion of the greater extent of the internal sur- face of the former intestines, from the number of their valvulse con- niventes. The vessels of the mesentery, after having cleared the series of glands, and held some intercourse with the lymphatics of the spleen, liver, stomach, and pancreas, are reduced at last into one or more large trunks, which, observing the course of the su- perior mesenteric artery, empty near the root of the latter, but some- times lower down, into the thoracic duct. The absorbents of the Large Intestines are much less numerous than those of the small. They are also superficial and deep, and observe the course of the blood vessels. Those from the right por- tion and middle of the colon join the lacteals of the mesentery, while such as belong to the sigmoid flexure follow the inferior me- senteric artery up to the lumbar glands. Those of the rectum go partly into the lumbar and partly into the hypogastric glands, and as its blood vessels are more numerous than those of other portions of the large intestine, its absorbents are in the same propor- tion.* The Absorbents of the Liver are exceedingly numerous, and are * Cruikshank, loc. eit. ABSORBENTS OF THE ORGANS OF DIGESTION. 331 also injected with unusual ease from the larger into the smaller trunks, from the imperfection of the valvular arrangements. They are also superficial and deep. The Superficial Absorbents of the upper surface of the liver run in several divisions, the number of which is unsettled. Those near the middle front of the liver assemble into six or more trunks, which ascend the suspensory ligament, and enter the thorax between the diaphragm and the sternum. They are joined by several trunks from the diaphragm, and continuing to ascend up the anterior me- diastinum between its laminae behind the sternum, they are re-en- forced by contributions from the pericardium, from the thymus gland, and from the anterior parietes of the thorax. The division then crosses the upper end of the descending cava, and those from the two sides assembling, they go in one or more large trunks along the left vena innominata, and finally empty into the left thoracic duct near its termination. Sometimes they enter into the right thoracic duct. It occasionally happens that a detachment of this division, instead of ascending through the mediastinum, is directed towards the coronary ligament of the liver; and being there joined by other vessels, it enters immediately into the thoracic duct at the upper part of tire abdominal cavity, or at the lower part of the thorax. Another division comes from the upper surface of the right lobe, and gaining the right lateral ligament, penetrates into the thorax through the diaphragm, and advancing along the costal margin of this muscle, terminates in the first division under the sternum. Sometimes one of its branches, thrice as large as a crow-quill, runs backward to the spine, and is inserted into the thoracic duct behind the oesophagus, without passing through any gland; there are also, occasionally, several other arrangements of the trunks of this di- vision.* Another division comes from the upper surface of the left lobe of the liver ; and its trunks advancing to the left lateral ligament, get into the thorax through the diaphragm. Some of the trunks then run forward on the convexity of this muscle, to terminate in the trunks under the sternum, while others retire backward to end in * Cruikshank, loc. cit. 332 ABSORBENT SYSTEM. the glands around the oesophagus, immediately above the dia- phragm. There are various departures from this general arrangement of the absorbents on the upper surface of the liver; as their trunks invari- ably reach the thoracic duct ultimately, the particular routes do not seem to be rigidly fixed. The Superficial Absorbents of the under surface of the liver pre- sent, also, diversities, but they are seldom arranged into so many divisions as those of the upper surface. They communicate freely with the latter, and also with the profound, and, finally, assembling in the transverse fissure, they descend along the capsule of Glisson to join and anastomose with the contiguous trunks from the alimen- tary canal, from the pancreas, and from the spleen. The Deep Absorbents of the liver follow the branching of the vena portarum, and, emerging at the transverse fissure, pass through the glands in the capsule of Glisson, associating themselves at the same time with the superficial trunks, and having a common termination with them. By putting a ligature around the vena portarum of a living animal, many of them are included in it ; they then become exceedingly turgid, and are seen to diverge through the liver like the pori biliarii. The liver is said to be more abundantly furnished with absorbents than any other viscus. The Absorbents of the Spleen are also superficial and deep-seated. The former are between the peritoneal and the proper coat, and are injected with some difficulty in the human subject, but are very demonstrable and numerous in the calf. The latter emerge at the fissure of the spleen, and, traversing the glands that lie along the course of the splenic artery, receive successively the absorbents from the pancreas. They, finally, end in the thoracic duct, after recipro- cal junctions, and anastomose with the vessels from the stomach and liver. The Absorbents of the Pancreas are also numerous, and may be injected, contrary to their circulation, from those of the liver. They arise from the substance of the pancreas, like its. vessels, ABSORBENTS OF THE ABDOMEN. 333 by short trunks, which join those of the Splenic Plexus at right angles. The Absorbents of the Kidneys are superficial and deep ; the former, though numerous, are too small in the healthy state of these organs to be well seen, but they become very distinct from disease, and converge from its periphery to its fissure. The deep absorbents accompany the vessels, and, emerging with them at the fissure, are joined with the superficial; they all then run along the emulgent vessels, and have frequent anastomoses with those of the testicles or ovaries, and with those of the capsulae renales. These absorbents may be filled by putting a pipe into- the excretory duct of the kidney. The Absorbents of the Capsulae Renales unite to those from the kidneys, and, therefore, terminate with them in the lumbar glands Of the Absorbent Glands of the Abdomen. The cavity of the abdomen contains many more glands that any other region of the body, on account of the very great extension of the serous system in it; of the functions exercised by its viscera; and of its being traversed by the absorbents of the lower extremities. Many of these Glands have already- been described under the de- nomination of hypogastric, and external iliac ; in addition to which there are a few between the laminae of the meso-reetum in front of the sacrum. The Mesenteric Glands are exceedingly numerous, and amount to between one and two hundred ; they begin at an inch or two from the small intestines, and may be traced to the root of the mesentery, being placed between its layers, on the convex side of the upper mesenteric artery. As the intestinal cartal is longer in some indivi- duals than in others, they are proportionately more numerous. Their largest size seldom exceeds that of an almond : those belonging to the jejunum are rather more developed than such as belong to the ilium, and they all augment in size as they approach the root of the ipesentery. The Glands of the Mesocolon are placed between the laminae of 29 * 334 ABSORBENT SYSTEM. this membrane, near the intestine ; they receive the absorbents from the large intestines, are much smaller than those of the mesentery, and their number seldom exceeds fifty. Some few of them are situ- ated near the root of the mesocolon. They are by no means so dis- posed to tumefaction from scrofulous affections as those of the Me- sentery. It is stated by Winslow, that lie demonstrated to the Academy of Sciences at Paris, chyle in the absorbents of the Meso- colon ; this fact will assist us in accounting for the effects of nutritive clysters. The Gastro-Epiploic Glands are situated between the laminae of the omenta, where they join the curvatures of the stomach. Their number seldom exceeds four or five for each curvature, and they receive the absorbents of the stomach and omenta. The Coeliac Glands are those which belong to the liver, the spleen, and the pancreas ; they follow the course of the blood vessels of these organs, and are traversed by their absorbents. The trunk of the vena portarum is surrounded by them, and Mr. Cruikshank says, that he has seen the biliary and pancreatic ducts in a state of com- pression from their tumefaction. The Lumbar Glands are very numerous and large ; they are scattered over the whole region, from the base of the sacrum to the pillars of the diaphragm, lying on each side of the bodies of the lumbar vertebrae, and in front of the abdominal aorta and vena cava, being concealed by the root of the mesentery and of the mesocolon. They may be considered as continuations of all the preceding con- geries of glands in the abdomen, and, therefore, when they, along with the vessels leading to them, are successfully injected, they form so thick a plexus of absorbents, reaching from the pelvis to the con- cavity of the diaphragm, that the great blood vessels can scarcely be seen for them. Many of the vessels reaching from one to another are as large as a crow-quill. SECT. VI. — ABSORBENTS OF THE VISCERA OF THE THORAX. The Absorbents of the Lungs are thought to be next in abundance after those of the liver, and are likewise divided into two sets, the ABSORBENTS OF THE THORAX. 335 superficial and the deep-seated. The former are beneath the pleura pulmonalis. Mr. Cruikshank* says, that they are not always to be found, though commonly he has readily shown them covering with their meshes the whole external surface of the lung. The larger meshes follow the interstices of the lobules, and within them are others of extreme delicacy. The same author states, that one of the easiest methods of finding them, is to inflate the lungs of a still-born child, from the trachea, and the air in passing from its proper cells, will get into the absorbents; a puncture being then made into one of the latter, quicksilver may be very readily introduced. Some of their trunks penetrate to the bottom of the fissures of the lungs, and pass through the glands there, while others continue more superficial along the internal face of the lung, and so reach the bronchial glands. The deep absorbents of the lungs observe the course of the pul- monary vessels and of the bronchia. They arise from the substance of the lung, anastomose very freely with the superficial vessels, and in parting from the lung, pass through the bronchial glands, where they are joined by the superficial. By the junction of the branches from the left lung, three consi- derable trunks are formed ; one, which is sometimes the size of a goose-quill, is inserted into the thoracic duct, immediately behind the bifurcation of the trachea ; another ascends between the trachea and the oesophagus, to join the thoracic duct near its termination; and the third joins the glands belonging to the absorbents of the heart, f The absorbents of the right lung also coalesce into three principal trunks at the root of the lung: one of them ascends across the front of the superior cava, making, in its course, many elegant convolu- tions, and at length terminates in the second trunk on the left side.j; The other trunks, ascending on the side of the trachea, and having traversed their glands, discharge into the right thoracic or brachio- cephalic trunk, or else near it into the right internal jugular, or into the right subclavian vein. There are, in these respects, diversities in different subjects. The trunks of the Absorbents of the Heart follow the course of the coronary vessels, and distribute themselves by branches over its whole surface. They are, without previous management, easily * Loc. cit. p. 194. f Cruikshank, loc. cit. % Ibid. 336 ABSORBENT SYSTEM. discovered ; but if the heart be macerated in water for several days, so as to become somewhat putrid, the absorbents are filled and dis- tended by the gaseous exhalation : on the puncture of one of these vessels and the introduction of a pipe, they may all be readily filled. There are three principal trunks of these absorbents ; one follows the right coronary artery to the root of the aorta, and then ascends over the front surface of the latter to the top of its arch, where it enters a gland. The other two trunks follow the two principal branches of the left coronary artery, and, coalescing near its origin, they ascend to the bifurcation of the pulmonary artery, and from that along the posterior face of the arch of the aorta, to enter a gland between it and the trachea. These several vessels subsequently traverse the lymphatic glands about the trachea, common to the heart and to the lungs : and ultimately terminate under varied cir- cumstances, either directly or indirectly, in the left thoracic duct, the left internal jugular, or the left subclavian vein. Mr. Cruikshank says, that the right coronary trunk empties into the lymphatic trunks of tlie right side of the neck, which shows that there is no fixed arrangement. The Absorbents of the Pericardium may also be found ; they ter- minate like the others of the heart, in the bronchial glands, and are particularly associated with those of the thymus gland. The Absorbents of the (Esophagus are so numerous as to form a:, plexus from one end to the other of it. They run into the bronchial glands, and, therefore, have a common termination with the absor- bents of the heart and lungs. Mr. Cruikshank says, that he has reason to believe that he has seen life sustained through them alone and the absorbents of the mouth, in a case where stricture prevailed for some months just above the cardia, and where the food, after remaining for three or five minutes in the oesophagus, was vo- mited up.* The Absorbents of the Thymus Gland are very abundant in the infant, but diminish with the rest of the structure in the adult : they terminate in the bronchial glands also. * A, case somewhat similar occurred in the practice of Dr. Physick. ABSORBENTS OF THE PARIETES OF THE TRUNK. 337 SECT. VII. — ABSORBENTS OF THE PARIETES OF THE TRUNK. In addition to the absorbents mentioned as belonging to the in- ternal and external parietes of the pelvis, there are some others belonging to this cavity, as the ilio lumbar, the sacral, and the cir- cumflex. The Ilio Lumbar Lymphatics come from the parts to which the artery of the same name is distributed, and, assembling into two or more large trunks which pass beneath the psoas magnus muscle, one of them joins the lumbar glands, and another the hypogastric. The Sacral Lymphatics arise from the cellular tissue in front of the sacrum and from the spinal canal in the latter. Emerging through its foramina in front, they terminate in the lower part of the lumbar and in the hypogastric plexus. The Circumflex Iliac Lymphatics attending the artery of the same name, arise from the lateral inferior parietes of the abdomen, in the thickness of its broad muscles ; the several branches assemble into a few trunks, which descend along the posterior margin of Poupart’s ligament to terminate in the external iliac plexus. The Epigastric Absorbents are derived from the inferior anterior parietes of the abdomen, along the region of distribution of the epi- gastric artery. Their trunks coalesce into larger ones, and descend along this artery to end in the external iliac plexus, near the crural arch. The Lumbar Absorbents arise from the muscles of the loins, from the posterior part of those of the abdomen, and from the spinal cavity. Their trunks correspond with the lumbar arteries, and passing beneath the psoas magnus muscle towards the spine, they terminate in the lumbar glands. The Intercostal Absorbents take their origin from the parietes of the thorax, and following the course of the respective intercostal arteries, pass through some small glands occasionally found be- 338 ABSORBENT SYSTEM. tween the external intercostal muscles near the heads of the ribs. They are there joined by trunks from the spinal cavity and from the muscles of the back, and afterwards passing through some small glands on the front of the vertebral column, they anastomose more or less with one another, and finally terminate in the left thoracic duct. The absorbents of the pleura costalis and of the posterior part of the pericardium terminate in the intercostals. The Internal Mammary Absorbents have their roots in the ante- rior region of the parietes of the abdomen, above the umbilicus, where they anastomose with the epigastric. They ascend, along with the internal mammary arteries, behind the sternal cartilages, pass through some small glands, and receive contributions from the anterior extremities of the intercostal spaces. Those of the left side, assembling into one or two trunks, cross in front of the left sub. clavian vein, traverse the inferior cervical glands, descend after- wards from this point, and terminate in the left thoracic duct, or in one of the contiguous trunks of the venous system. Those on the right execute the same movements, but terminate in the right thoracic duct, or in one of the contiguous venous trunks on that side. The Absorbents of the Diaphragm are exceedingly numerous, and very much connected with those of the liver. The anterior ones join the internal mammary absorbents, while the posterior fol- low the phrenic arteries, or go to contiguous trunks belonging to the intercostals. The front ones on the right side, then terminate in the right thoracic duct, while the remainder go in the various routes of the absorbents, with which they are connected, into the left thoracic duct. They are principally seen on its upper surface. Mr. Cruik- shank* says, that he once saw them to the amount of three hundred or more, filled with chyle from the mesentery that had passed through the substance of the liver. Asellius was, therefore, probably justified by an accident of this kind, in asserting that the lacteals went to the liver. The Absorbents of the Female Mammae, like their arteries and veins, are superficial and deep ; the former attend the external tho- * Loc. cit. p. 90. THORACIC ABSORBENTS. 339 racic blood vessels, and the latter the internal mammary. The superficial arise from the circumference of the nipple, from the skin and cellular membrane, and according to the injections of Mr. Cruik- shank, communicate freely with the vesicles of the tubuli lactiferi. They run towards the axilla, having occasionally to pass through some glands which are situated half way ; they then enter the first series of glands of the axilla in their direction, and afterwards others successively, until they terminate in the lymphatic trunks of the up- per extremity, high up in the arm-pit. Some few of these superficial vessels ascend over the pectoralis major to the glands in the neck, just above the clavicle. The deep absorbents of the mammse arise from their thoracic face, and penetrating the intercostal spaces, join the absorbents that at- tend the internal mammary artery. Of the Absorbent Glands in the Thorax. There are, as mentioned, a few small glands in the intercostal spaces near the heads of the ribs between the internal and external intercostal muscles, intended to receive the lymphatics of these spaces. There are also several small ones situated on the front of the dorsal vertebrae, along the aorta and the oesophagus, in the pos- terior mediastinum. There are also from six to ten along the in- ternal mammary artery ; and some others in the anterior mediastinum, along the sternal face of the pericardium. They are said to be very rarely affected by disease. The most considerable and striking glands in the thorax are those called Bronchial or Pulmonary, which receive the absorbents of the lungs. They cluster about the bifurcation of the trachea, and follow the bronchia for some distance into the substance of the lungs. They are from ten to twenty in number, and vary in size from an inch to a few lines in diameter. Till puberty they have a reddish colour, but afterwards they become gray, and finally black, following in these respects the change of colour in tire lungs. According to Mr. Pearson, their complexion depends upon the deposit of pure carbon. In pulmonary consumption these glands are always enlarged, and look scrofulous. 340 ABSORBENT SYSTEM. SECT. VIII. — OF THE THORACIC DUCTS.* The Left Thoracic Duct ( Ductus Thoracicus Sinister ) is the main stream of the absorbent system to which almost all the others are but tributary, and by divers routes ultimately find their way into it. It begins about the second or third lumbar vertebra, in front of its body. Shortly after its commencement, while still in the abdomen, it suffers a dilatation more or less considerable, and varying in its shape in different subjects. This is called the Reservoir of Pecquet, or the Receptaculum Chyli ; the dilatation, however, is frequently absent, and does not seem to be an essential part of the structure: in our preparations at the University some have it, and others have it not. The thoracic duct enters the thorax between the crura of the dia- phragm, to the right of, and behind the aorta ; it then ascends on the front of the dorsal vertebra, between the aorta and the vena azygos, in front of the right intercostal arteries, and behind the oesophagus. At the fourth dorsal vertebra it begins to incline in its ascent to the left side, and then ascends into the neck near the head of the first rib ; it rises commonly as high up as the upper margin of the seventh cervical vertebra ; it then turns downwards and forwards, over the left subclavian artery within the scaleni muscles, and, finally discharges into the angle of junction of the left subclavian and in- ternal j ugular vein. The preceding is the most simple, and perhaps the most common form, under which the thoracic duct is presented, but varieties are continually occurring in its place and mode of origin, in its trunk, and its manner and place of termination. It commonly begins by the union of three absorbent trunks ; one for each side of the pelvis, along with the corresponding lower extremity; and a middle one for the chyliferous vessels, which unites with the common trunk of the other two, a few lines above its point of formation ; on other occa- sions, the chyliferous trunks join it in a confused manner by nine or ten distinct channels. Sometimes an intricate plexus of several large trunks; derived from the lumbar and mesenteric glands, by the gradual reduction of the number of meshes from the successive joining of trunks; begins to assume, at the crura of the diaphragm, * Anat. Atlas, Fig. 502. THORACIC DUCTS. 341 the form of a solitary trunk, which is the thoracic duct. The trunk of the duct is also disposed to keep up the anastomosing plan, even in the thorax ; we hence see it sometimes dividing itself into two or three channels of equal size, which unite again after a shorter or longer distance, and perhaps in a little space repeat the same ar- rangement : sometimes a small arm is sent off, which runs along for an inch or two, and joins into the parent stream; sometimes spiral turns are adopted by the thoracic duct ; sometimes nodosities, or small pouches are formed on its sides ; sometimes it is dilated at in- tervals in its whole circumference. Sometimes it splits into several channels at its termination ; one channel terminating in one vein and another in a contiguous one, of the several trunks forming the vena innominata ; on other occasions, instead of entering into a venous trunk of the left side, it goes into the corresponding one of the right. Commonly, it is about the size of a large crow-quill, but some- times as large as a goose-quill, or even still more voluminous, seem- ing to be in a varicose state, of which Mr. Cruikshank mentions an example where it was half an inch in diameter, and took two pounds of mercury to fill it. There is generally a pair of valves at the ter- mination of the thoracic duct, or if it be divided into several streams there is a pair at the embouchure of each, to keep the venous blood out of it. There are also valves in its length, but they are not numerous, and vary in different subjects. The thoracic duct, as stated, is the grand outlet for the lymphatics of the left side of the head and neck, of the left superior extremity, of the left side of the thorax, of all the intercostal spaces, of the viscera of the abdomen, and of the inferior extremities. Though those of the viscera of the abdomen and of the lower extremities have this route, yet, from the observations of Mr. Lippi, of Florence, as mentioned, they have also some more direct means of getting into the general circulation. For example, he has found several large lymphatic trunks emptying into the ascending cava, one of them opposite the third lumbar vertebra; another into the primitive iliac vein : he has also found some of the lymphatics of the liver dis- charging into the vena portarum. The Right Thoracic Duct, ( Ductus Thoracicus Dexter,) as it is called, but more properly the Right Brachio-cephalic, after the name given by M. Chaussier to the vein, is not more than an inch long, and descends to empty itself, as mentioned, into the junction of the Vol. II.— 30 342 ABSORBENT SYSTEM. right interna] jugular with the right subclavian vein. It is derived from the lymphatic trunks of the right side of the head and neck, of the right upper extremity, the superficial lymphatics of the right side of the thorax, the lymphatics of the right lung, of the right side of the diaphragm, and some of those of the right side of the liver, the courses of all of which have been detailed. Though the single trunk is formed from these several tributary streams, yet the latter have sometimes several embouchures into the venous system at or near the point mentioned, and, as on the other side of the body, there is a proper security, by valves from the in- troduction of blood into them. There is always an ample system of anastomosis, not only between the branches which concur to form the right and left thoracic ducts, but even between the ducts themselves,* so that if one be occluded or impeded, its circulation can be turned into the other, as in the case of veins. * Meckel, Man. D’Anat., tom. ii., p. 581. BOOE IX* PART f. HISTOLOGY OF THE NERVOUS SYSTEM, Nervous System. The Essential ingredient of this System is a peculiar animal matter called Neurine , the texture of which is so soft, that in the natural state it has the least possible consistence. It is, therefore, protected in a variety of ways ; by being enclosed in bone, where it is collected in large masses ; and by being surrounded by ligamentous or cellular matter, where flexure is required. The nervous system in man, and other vertebrated animals, con- sists in two portions of dissimilar forms ; one is spheroidal, elongated at its base into a cylindrical process, and is contained in the cranium and in the spinal canal ; the other is an assemblage of arborescent rays, which proceed from different points of the first portion, to every part of the body. The first portion is the Central or Internal part of the nervous system, composed of the Brain and Spinal Marrow ; while the radiating portion is called the External or Peri- pheral, and consists in the Nerves of the brain and spinal marrow. The nervous system is remarkable for its symmetry. As it is uni- versally double, it very seldom happens that any striking difference of it on the two sides of the body is manifested, particularly as re- gards its Central portion ; it is said, however, that aberrations, in this respect, are more common in man than in other mammiferous animals. 344 NERVOUS SYSTEM. The central portion of the nervous System is composed of two kinds of the substance called Neurine, distinguished by their colour and relative situation : one is improperly enough called Medullary, ( Substantia Medullaris ,) but as the name is now sanctioned by uni- versal usage, it is impossible to dispense with it. The other is called Cineritious, ( Substantia Cinerea ) with, perhaps, sufficient propriety, from its colour. They are both of a soft pulpy consistence, and constitute the chief mass of the brain and spinal marrow: some an- atomists have desired to add, from a slight distinction of colour, two other substances, a yellow and a black, but that seems unne- cessary, and has not been generally acknowledged. These sub- stances differ from one another in regard to their quantity, the me- dullary being more abundant than the cineritious ; it is also harder, and receives fewer vessels. The cineritious, or gray substance of the brain and spinal chord is formed of globules, according to Valentin, of a spheroidal shape. These globules have a nucleus,, and in the circumference of this a nucleolus. The quantity of these globules determines the shade of the gray substance, but there are parts of the latter of a darker colour which is owing to a pigment of the globule. It is thought by Muller, that the cineritious globules of the nervous system are connected together by peculiar filaments ; the same ar- rangement existing, in the ganglia of nerves. The Medullary Matter, when quite fresh and scraped in particular directions has a filamentous condition, which may be rendered still more distinct by hardening it in alcohol, in boiling oil, in a solution of the neutral salts, or im diluted mineral acids. If an attempt be then made to tear it, it will be immediately perceived that the fibres separate in a fixed direction, and in no other. These fibres, are, in some instances, parallel ; in others, concentric ; and in others, di- verging or converging.* The elementary form of white nervous matter consists in those fila- ments or threads, and which in the nerves are held together by cellular substance. Each filament in both the brain and the nerves consists in a membranous tube, containing a soft matter. In the brain the * See Lessons on Practical Anatomy, by W. E. Horner, for description of Brain according to Gall and Spurzheim. HISTOLOGY OF THE NERVOUS SYSTEM. 345 latter is a mere pulp, but in the nerves it may be separated from its tube in a linear form for some distance. The fibres or filaments of the brain when pressed upon, become swollen at intervals so as to be knotted or like a string of beads, and if the pressure be much they are separated into globules of dif- ferent sizes. The elementary nervous fibres are smaller in the brain and spinal marrow than elsewhere ; in the nerves themselves they vary from \\ — July 1846. SCR 0~F U L A, ITS NATURE, ITS PREVALENCE, ITS CAUSES, AND THE PRINCIPLES OF ITS TREATMENT. BY BENJAMIN PHILLIPS, M. D., F. R. S., &c. In one neat octavo volume , with a plate. u There can be no doubt that there was ample room for a fresh review of scrofula, and that a work on tho subject, from a writer of learning, industry, and talent, must be acceptable; and such, after a careful perusal, the work before us appears to be. Very uncommon pains seem to have been taken in collecting information from men as well as hooks. Our impression of this work is, that it is a very important accession to our profes- sional literature, and does the greatest credit to the industry, research and talent of the author. Its utility is, we think, likely to extend far beyond the limits of professional society.” — The London Medical Gazette. This work is just published. The author has been for years engaged in the collection of materials and sta- tistics from all parts of the world. SMALL BOOKS ON GREAT SUBJECTS. . v « u ’ re. id i *, “The Connection between Physiology and Intellectual Science.” Forming No. 2 of a series of small works now issuing at Twenty-five Cents each. To be followed shortly by “ Philosophical Theories and Philosophical Experience,” — On Man’s Power over Himself to Prevent or Control Insanity,” — “An Introduction to Practical Organic Che- mistry,” — “An Introduction to Vegetable Physiology, with References to the Works of De Can- dolle, Lindley, &c.,” and several other new and valuable works. Each one to form a very neat and portable volume. OCr These works have acquired great popularity in England, and the publishers take pleasure in introducing the series neatly printed, and at so low a price. LEA & BLANCHARD’S PUBLICATIONS. 13 COMPENDIUM OF CHAPMAN’S LECTURES. A COMPENDIUM OF LECTURES ON THE THEORY AND PRACTICE OF MEDICINE. DELIVERED BY PROFESSOR CHAPMAN IN THE UNIVERSITY OF PENN- SYLVANIA. PREPARED. WITH PERMISSION. FROM DR. CHAPMAN’S MANUSCRIPTS, AND PUBLISHED WITH HIS APPROBATION, BY N. D. BENEDICT, M. D. IN ONE VERY NEAT OCTAVO VOLUME. CONTENTS. Remarks on the Classification ofDiseases — Feverin General — Intermittent Fever — Remittent Fever ■ — Continued Fever, (Mild, Intermediate, and Extreme Forms) — Yellow Fever — Endemic Pneu- monic, or Spotted Fever — Diseases of the Heart and Blood-vessels, (Inflammatory, Organic, and Nervous) — Acute Carditis, Pericarditis, and Endocarditis — Chronic Carditis, Pericarditis, and En- docarditis — Hypertrophy of the Heart — Dilatation of the Heart — Atrophy of the Heart — Rupture of the Heart — Affections of the Valves of the Heart — Palpitations — Acute Arteritis — Degenera- rations of Arteries — Aneurism of Arteries — Phlebitis — Acute Inflammation of the Throat — Chronic Inflammation of the Throat — Dysphagia — Parotitis — Dysentery, (Inflammatory) — Dysentery, (Con- gestive) — Diarrhoea — Cholera Morbus — Cholera Infantum — Flatulent Colic — Bilious Colic- — Colica Pictonum — Acute Peritonitis — Chronic Peritonitis — Acute Catarrh — Catarrhus jEstivus— Chronic Catarrh — Acute Bronchitis — Chronic Bronchitis — Catarrhus Senilis — Acute Infantile Bronchitis — Chronic Infantile Bronchitis — Croup — Acute Infantile Asthma — Whooping-Cough — Acute Laryn- gitis — Chronic Laryngitis — Pleuropneumonia — Congestive Pneumonia — Chronic Pleurisy and Pneumonia — Apoplexy — Palsy — Epilepsy — Hysteria — Chorea — Neuralgia — Diabetes. The subjects treated of in this volume are entirely distinct from those considered in Dr. Chapman’s two works on “Thoracic and Abdominal Viscera,” and on “Eruptive Fevers,” &c. These works are all printed and bound to match, and form three very neat octavo volumes. LECTURES ON THE MORE IMPORTANT DISEASES OF THE THORACIC AND ABDOMINAL VISCERA. DELIVERED IN THE UNIVERSITY OF PENNSYLVANIA. BY N. CHAPMAN, M. D. PROFESSOR OF THE THEORY AND PRACTICE OF MEDICINE, ETC. In One Volume, Octavo. CHAPMAN OfT~FEVERS, &c. LECTURES ON THE MORE IMPORTANT ERUPTIVE FEVERS, HAEMORRHAGES AND DROPSIES, AND ON GOUT AND RHEUMATISM, DELIVERED IN THE UNIVERSITY OF PENNSYLVANIA. By N. CHAPMAN, M.D., PROFESSOR OF THE THEORY AND PRACTICE OF MEDICINE, ETC. ETC. In One Neat Octavo Volume. “ The name of Chapman stands deservedly high in the annals of American medical science. A teacher anil a lecturer for nearly forty years, in the oldest and, we believe, the first medical school on this side of the At- lantic, the intimate friend and companion of Rush, Kuhn, Physick, Wislar, Woodhouse, Dewees, and a host of others, scarcely less renowned, Professor Chapman reflects upon the profession of this generation something of the genius and wisdom of that which has passed ; he stands out the able and eloquent champion of the doc- trines and principles of other times, when Cullen’s “ first lines” formed the rule of faith for all the Doctors in Medicine throughout Christendom. In him is embodied the experience of three score and ten, strengthened by reading, and enlightened by a familiar intercourse with many of the ablest medical men in the New and Old World. In conclusion, we must declare our belief that the name of Chapman will survive when that of many of his cotemporaries shall have been forgotten ; when other generations shall tread the great theatre of human affairs, and when other discoveries yet undisclosed, shall shed a brighter light upon the path of medi- cal science. The various lectures which he has been publishing, containing, as they do, the doctrines that he has so long and so eloquently taught to large and admiring classes, we doubt not will be welcomed with delight by his numerous pupils throughout the Union .”— Netc Orleans Medical Journal. 14 LEA & BLANCHARD’S PUBLICATIONS. HORNER’S ANATOMY, NEW EDITION— To be Ready by October. SPECIAL ANATOMY AND HISTOLOGY. BY WILLIAM E. HORNER, M. D., PROFESSOR OF ANATOMY IN THE UNIVERSITY OF PENNSYLVANIA, &c. &c. SEVENTH EDITION, WITH MANY IMPROVEMENTS AND ADDITIONS. In two Octavo Volumes, ivith Illustrations on Wood. This standard work has been so long before the profession, and has been so extensively used, that, in announcing the new edition, it is only neces- sary to state that it will undergo a most careful revision ; the author will introduce many illustrations relating to Microscopical Anatomy, and will add a large amount of text on these various points of investigation that are rapidly advancing and attracting so much attention. Tins new edi- tion will be arranged to refer conveniently to the illustrations in Smith and Horner’s Anatomical Atlas, and will be ready for the Fall Lectures. HORNER’S DISSECTOR. THE UNITED STATES DISSECTOR, BEING A NEW EDITION, WITH EXTENSIVE MODIFICATIONS, AND ALMOST REWRITTEN, OF “HORNER’S PRACTICAL ANATOMY.” IN ONE VERY NEAT VOLUME, ROYAL 12mo. With many Illustrations on Wood. The numerous alterations and additions which this work has under- gone, the improvements which have been made in it, and the numerous wood-cuts which have been introduced, render it almost a new work. It is the standard work for the Students in the University of Pennsyl- vania. BUDD ON THE LIVER. ON DISEASES OF THE LIVER. BY GEORGE BUDD, M.D., F.R.S., Professor of Medicine in King’s College, London, &c. &c. With colored plates, and numerous wood-cuts. In one neat octavo volume. i: We cannot too strongly recommend llie diligent study of tliis volume. The work cannot fail to rank the name of its author among the most enlightened pathologists and soundest practitioners of the day.”— Medico- Cltirurgical Review. A MLA GNTFICENT AND CHEAP WOES. SMITH & HORNER’S ANATOMICAL ATLAS. Just Published, Price Five Dollars in Parts. AN ANATOMICAL ATLAS ILLUSTRATIVE OF THE STRUCTURE OF THE HUMAN BODY. BY HENRY H. SMITH, M. D., Fellow of the College of Physicians, $c. UNDER THE SUPERVISION OF WILLIAM E. HORNER, M. D., Professor of Anatomy in the University of Pennsylvania. In One large Volume, Imperial Octavo. This work is but just completed, having been delayed over the time intended by the great difficulty in giving to the illustrations the desired finish and perfection. It consists of five parts, whose contents are as follows : Part I. The Bones and LigamentSj with one hundred and thirty engravings. Part II. The Muscular and Dermoid Systems, with ninety-one engravings. Part III. The Organs of Digestion and Generation, with one hundred and ninety-one engravings. Part IV. The Organs of Respiration and Circulation, with ninety-eight engravings. Part V. The Nervous System and the Senses, with one hundred and twenty-six engravings. Forming altogether a complete System of Anatomical Plates, of nearly SIX HUNDRED AND FIFTY FIGURES, executed in the best style of art, and making one large imperial octavo volume. Those who do not want it m parts can have the work bound in extra cloth or sheep at an extra cost. This work possesses novelty both in the design and the execution. It is the first attempt to apply engraving on wood, on a large scale, to the illustration of human anatomy, and the beauty of the parts issued induces the publishers to flatter themselves with the hope of the perfect success of their undertaking. The plan of the work is at once novel and convenient. Each page is perfect in itself, the references being immediately under the figures, so that the eye takes in the whole at a glance, and obviates the necessity of continual reference backwards and forwards. The cuts are selected from the best and most accurate sources ; and, where neces- sary, original drawings have been made from the admirable Anatomical Collection of the University of Penn- sylvania. It embraces all the late beautiful discoveries arising from the use of the microscope in the investi- gation of the minute structure of the tissues. In the getting up of this very complete work, the publishers have spared neither pains nor expense, and they now present it to the profession, with the full confidence that it will be deemed all that is wanted in a scientific and artistical point of view, while, at the same time, its very low price. places it within the reach of all. It is particularly adapted to supply the place of skeletons or subjects , as the prof ess ion will see by examining the list of plates M These figures are well selected, and present a complete and accurate representation of that wonderful fabric, the human body. The plan of this Atlas, which renders it so peculiarly convenient for the student, and its superb artistical execution, have been already pointed out. We must congratulate the student upon the completion of this atlas, as it is the most convenient work of the kind .that has yet appeared; and, we must add, the very beautiful manner in which it is ‘ got up 5 is so creditable to the country as to be flattering to our national pride.” — American Medical Journal. “This is an exquisite volume, and a beautiful specimen of art. We have numerous Anatomical Atlases, but we will venture to say that none equal it in cheapness, and none surpass it in faithfulness and spirit. We strongly recommend to our friends, both urban and suburban, the purchase of .this excellent work, for which both editor and publisher deserve the thanks of the profession.” — Medical Examiner. “We would strongly recommend it, not only to the student, but also to the working practitioner, who, although grown rusty in the toils of his harness, still has the desire, and often the necessity, of refreshing his knowledge in this fundamental part of the science of medicine.” — New York Journal of Medicine and Surg. “ The plan of this Atlas is admirable, and its execution superior to any thing of the kind before published m this country. It is a real labour-saving affair, and we regard its publication as the greatest boon that could be conferred on the student of anatomy. It will be equally valuable to the practitioner, by affording him an easy means of recalling the details learned in the dissecting room, and which are soon forgotten.” — American Medi- cal Journal. “It is a beautiful as well as particularly useful design, which should be extensively patronized by physicians, surgeons and medical students.” — Boston Med. and Surg. Journal. “ It has been the aim of the author of the Atlas to comprise in it the valuable points of all previous works, to embrace the latest microscopical observations on the anatomy of the tissues, and by placing it at a moderate price to enable all to acquire it who may need its assistance in the dissecting or operating room, or other field of practice.” — Western Journal of Med. and Surgery. “These numbers complete the series of this beautiful work, which fully merits the praise bestowed upon the earlier numbers. We regard all the engravings as possessing an accuracy only equalled by their beauty, and cordially recommend the work to all engaged in the study of anatomy.” — New York Journal ofMedicme and Surgery. “A more elegant work than the one before us could not easily be placed by a physician upon the table of bis student.” — Western Journal of Medicine and Surgery. “We were much pleased with Part I, but the Second Part gratifies us still more, both as regards the attract- ive nature of the subject, (The Dermoid and Muscular Systems.) and the beautiful artistical execution of the d lustrations. We have here delineated the most accurate microscopic views of some of the tissues, as, for instance, the cellular and adipose tissues, the epidermis, rete mucosum and cutis vera, the sebaceous and perspiratory organs of the skin, the perspiratory glands and hairs of the skin, and the hair and nails. Then follows the general anatomy of the muscles, and, lastly, their separate delineations. We would recommend this Anatomical Atlas to our readers in the very strongest terms.” — New York Journal of Medicine and Sur- gery. 16 LEA & BLANCHARD’S PUBLICATIONS. THERAPEUTICAL LIBRARY. PEREIRA’S MATERIA MEDICA. WITH NEARLY THREE HUNDRED ENGRAVINGS ON WOOD. A NEW EDITION, LATELY PUBLISHED. THE ELEMENTS OF MATERIA MEDICA AND THERAPEUTICS. COMPREHENDING THE NATURAL HISTORY, PREPARATION, PROPERTIES, COMPO- SITION, EFFECTS AND USES OF MEDICINES. BY JONATHAN PEREIRA, M.D., F.R.S. and L.S., Member of the Society of Pharmacy of Paris; Examiner in Materia Metlica and Pharmacy of the University of London ; Lecturer on Materia Medica at the London Hospital, &c. &.C. Second American, from the last London Edition, enlarged and improved. WITH NOTES AND ADDITIONS BY JOSEPH CARSON, M.D. In Two Volumes, Octavo, containing Fifteen Hundred very large Pages, illustrated by Two Hundred and Seventy-five Wood-cuts. Part I. contains the General Action and Classification of Medicines and the Mineral Materia Medica. Part II., the Vegetable and Animal Kingdoms, including diagrams explanatory of the Processes of the Pharmacopoeias, a tabular view of the History of the Materia Medica, from the earliest times to the present day, with the Introduction of the Processes of the New Edinburgh Pharmacopoeia, and a very copious index. It also contains additional articles on Blental Remedies, Light, Heat, Cold, Electricity, Magnetism, Exercise, Dietetics and Climate, and many additional Wood-cuts, illustrative of Pharmaceutical Operations, Crystallography, Shape and Organization of the Feculas of Commerce, and the Natural History of the Materia Medica. In passing through the press the second edition of this standard work, the opportunity has been taken by the editor to correct any mistakes or inadvertencies that may have escaped him or the author, in the first edition. It may now be considered as entirely worthy of the confidence of the physician and pharmaceutist, as an accurate edition of the most complete work extant on the subject. “An Eneyelopcedia of knowledge in that department of medical science — by the common consent of the pro- fession the most elaborate and scientific Treatise on Materia Medica in our language .” — Western Journal of Medicine and Surgery. THE STUDENT’S TEXT-BOOK OF MATERIA MEDICA. NOW AT PRESS, A MANUAL OF MATERIA MEDICA AND THERAPEUTICS. By J. FORBES ROYLE, M. D., PROFESSOR IN KING’S COLLEGE, LONDON. EDITED BY J. CARSON, M.D., Professor of Materia Medica and Pharmacy in the Philadelphia College of Pharmacy, etc. etc. In One Octavo Volume, with Numerous Splendid Illustrations. This work will contain all the most recent information and investigations in the various branches connected with the Materia Medica, and under the supervision of its able editor, will receive whatever alterations and additions may be necessary to adapt it to the United Slates Pharmacopoeia, and to the practice of this country. The high character of the author will attract attention to the work as a text-book for the next session of the various colleges, if ready. The numerous and beautiful illustrations will far surpass anything that has as vet been attempted in this way. This volume will be brought out in a style to match Fer- guson’s Surgery, Wilson’s Anatomy, &c., and will be sold at a low price. LEA & BLANCHARD’S PUBLICATIONS. 17 THE GREAT MEDICAL LIBRARY. THE CYCLOP/EDIA OF PRACTICAL MEDICINE; COMPRISING TREATISES ON THE NATURE AND TREATMENT OF DISEASES, MATERIA MEDICA & THERAPEUTICS, DISEASES OF WOMEN AND CHILDREN, MEDICAL JURISPRUDENCE, &c. &c. EDITED BY JOHN FORBES, M. D., F. R. S., ALEXANDER TWEED IE, M.D., F.R.S., AND JOHN CONOLLY, M.D. REVISED, WITH ADDITIONS, By ROBLEY DUNGLISON, M.D. THIS WORK IS NOW COMPLETE, AND FORMS • FOUR LARGE SUPER-ROYAL, OCTAVO VOLUMES, CONTAINING THIRTY-T WO . HUNDRED AND FIFTY-FOUR UNUSUALLY LARGE PAGES IN DOUBLE COLUMNS, PRINTED ON GOOD PAPER, WITH A NEW AND CLEAR TYPE. THE WHOLE WELL AND STRONGLY BOUND, WITH RAISED BANDS AND DOUBLE TITLES. Or, to be had in twenty-four parts, at Fifty Cents each. For a list of Articles and Authors , together with opinions of the press, see Supplement to the No- vember number of the Medical News and Library. This work having been completed and placed before the profession, has been steadily advancing in favor with all classes of physicians. The nu- merous advantages which it combines, beyond those of any other work ; the weight which each article carries with it, as being the production of some physician of acknowledged reputation who has devoted himself especially to the subject confided to him, the great diversity of topics treated of ; the compendiousness with which everything of importance is digested into a comparatively small space ; the manner in which it has been brought up to the day, everything necessary to the American prac- titioner having been added by Dr. Dunglison ; the neatness of its mecha- nical execution, and the extremely low price at which it is afforded, combine to render it one of the most attractive works now before the pro- fession. As a book for constant and reliable reference, it presents advan- tages which are shared by no other work of the kind. To country prac- titioners, especially, it is absolutely invaluable, comprising in a mode- rate space, and trifling cost, the matter for which they would have to accumulate libraries, when removed from public collections. The steady and increasing demand with which it has been favored since its completion, shows that its merits have been appreciated, and that it is now universally considered as the LIBRARY FOR CONSULTATION AND REFERENCE. 18 LEA & BLANCHARD’S PUBLICATIONS. WORKS BY PROFESSORS CHURCHILL, MEIGS, &c. CHURCHILL’S MIDWIFERY. A New Edition, Just Published. ON THE THEORY AND PRACTICE OF MIDWIFERY. BY FLEETWOOD CHURCHILL, M.I)., M.R. I. A., Licentiate of the College of Physicians in Ireland; Physician to the Western Lying-in Hospital ; Lecturer on Midwifery, &e., in the Richmond Hospital Medical School, &c. &c. WITH NOTES AND ADDITIONS BY ROBERT M. HUSTON, M.D., Professor of Materia Medica and General Therapeutics, and formerly of Obstetrics and the Diseases of Wo- men and Children in the Jefferson Medical College of Philadelphia; President of the Philadelphia Medical Society, &c. &c. SECOND AMERICAN EDITION. WITH ONE HUNDRED AND TWENTY-EIGHT ILLUSTRATIONS, ENGRAVED BY GILBERT FROM DRAWINGS BY BAGG AND OTHERS. In One beautiful Octavo Volume. The call for a second edition of Dr. Churchill’s Midwifery, within so short a time after the ap- pearance of the first, is satisfactory evidence that the profession in this country appreciate the high value of the work. Both as a text-book for the student and as a manual for the practitioner, it has a deservedly great reputation, especially for the fulness and clearness with which the physiological details are wrought out and brought to illustrate the practical part. To render the present edition worthy of a continuance of the favor and confidence so signally manifested towards its predecessor, the editor has carefully added all the new facts and observations which have transpired since the publication of the last edition, or such at least as appeared to him deserving of being recorded. These relate to some of the most important points in physiology and obstetrical practice. Various new illustrations have been introduced, and the whole brought up, as far as possible, to the day of publication. A NEW EDITION OF CHURCHILL ON FEMALES. THE DISEASES OF FEMALES, INCLUDING THOSE OF PREGNANCY AND CHILDBED. BY FLEETWOOD CHURCHILL, M.D., Author of “ Theory and Practice of Midwifery,” &c. &c. THIRD AMERICAN, FROM THE SECOND LONDON EDITION, WITH ILLUSTRATIONS- EDITED, WITH NOTES, BY ROBERT M. HUSTON, M. D., &c. &c. In One Volume, 8vo. “ In complying with the demand of the profession in this country for a third edition, the Editor has much pleasure in the opportunity thus afforded of presenting the work in its more perfect form. All the additional references and illustrations contained in the English copy are retained in this.” A TREATISE ON THE DISEASES OF FEMALES, AND ON THE SPECIAL HYGIENE OF THEIR SEX. WITH NUMEROUS WOOD-CUTS. BY COLOMBAT DE L’ISERE, M. D., Chevalier of the Legionof Honor; late Surgeon to the Hospital of the Rue de Valois, devoted to the Diseases of Females, &c. &c. TRANSLATED, WITH MANY NOTES AND ADDITIONS, By C. D. MEIGS, M.D., Professor of Obstetrics and Diseases of Women and Children in the Jefferson Medical College, &c. &c. In One Large Volume, 8vo. “We are satisfied it is destined to take the front rank in this department of medical science; it is beyond all comparison, the most learned Treatise on the Diseases of Females that has ever been written, there being more than one thousand distinct authorities quoted and collected by the inde- fatigable author. It is in fact a complete exposition of the opinions and practical methods of all the celebrated practitioners of ancient and modern times. The Editor and Translator has per- formed his part in a manner hardly to be surpassed. The translation is faithful to the original, and yet elegant. More than one hundred pages of original matter have been incorporated in the text, constituting a seventh part of the whole volume .” — New York Journal of Medicine. LEA & BLANCHARD’S PUBLICATIONS. 19 WORKS BY PROFESSOR W. P. DEWEES. MEW EDITIONS. DEWEES’S^MIDWIFESY, A COMPREHENSIVE SYSTEM OF MIDWIFERY. CHIEFLY DESIGNED TO FACILITATE THE INQUIRIES OF THOSE WHO MAY BE PUR- SUING THIS BRANCH OF STUDY. ILLUSTRATED BY OCCASIONAL CASES AND MANY ENGRAVINGS. Tenth Edition, with the Author's last Improvements and Corrections. BY WILLIAM P. DEWEES, M. D., LATE PROFESSOR OF MIDWIFERY IN THE UNIVERSITY OF PENNSYLVANIA, ETC. In one volume, octavo. That this work, notwithstanding the length of time it has been before the profession, and the numerous treatises that have appeared since it was written, should have still maintained its ground, and passed to edition after edition, is sufficient proof that in it the great practical talents of the author were fully placed before the profession. Of the book itself it would be superfluous to speak, having been so long and so favorably known throughout the country as to have become identified with American Obstetrical Science. DEWEES ON FEMALES. A TREATISE ON THE DISEASES OE FEMALES, BY WILLIAM P. DEWEES, M. D., &c. LATE PROFESSOR OF MIDWIFERY IN THE UNIVERSITY OF PENNSYLVANIA, ETC. EIGHTH EDITION, With the Author’s last Improvements and Corrections. In one octavo volume, with plates. D E W E E S ON CHI L D R E N . A TREATISE ON THE PHYSICAL AND MEDICAL TREATMENT OF CHILDREN, BY WILLIAM P. DEWEES, M.D., LATE PROFESSOR OF MIDWIFERY IN THE UNIVERSITY OF PENNSYLVANIA, ETC. ETC. EIGHTH EDITION. In one volume, octavo. This edition embodies the notes and additions prepared by Dr. Dewees before his death, and will be found much improved. The objects of this work are, 1st, to teach those who have the charge of children, either as parent or guardian, the most approved methods of securing and improving their physical powers. This is attempted by pointing out the duties which the parent or the guardian owes for this purpose, to this interesting but helpless class of beings, and the manner by which their duties shall be fulfilled. And 2d, to render available a long experi- ence to those objects of our affection when they become diseased. In attempting this, the author has avoided as much as possible, “technicality,” and has given, if he does not flatter himself too much, to each disease of which he treats, its appropriate and designating characters, with a fidelity that will prevent any two being con- founded together, with the best mode of treating them, that either his own experience or that of others has suggested. Physicians cannot too strongly recommend the use of this book in all families. ASHWELL ON THETdISEASES OF FEMALES. A PRACTICAL TREATISE ON THE DISEASES PECULIAR TO WOMEN. ILLUSTRATED BY CASES DERIVED FROM HOSPITAL AND PRIVATE PRACTICE. By SAMUEL ASHWELL, M. D., Member of the Royal College of Physicians ; Obstetric Physician and Lecturer to Guy’s Hospital, &c. Edited by PAUL BECK GODDARD, M. D. The whole complete in one large octavo volume. “ The most able, and certainly the most standard and practical work on female diseases that we have yet seen.” — Medico-Chirurgical Review. 20 LEA & BLANCHARD’S PUBLICATIONS. LATELY PUBLISHED, A NEW EDITION OF WILSON’S HUMAN ANATOMY, MUCH IMPROVED. A SYSTEM OTTuITN ANATOMY, GENERAL AND SPECIAL. BY ERASMUS WILSON, M.D., LECTURER ON ANATOMY, LONDON. SECOND AMERICAN EDITION, EDITED BY PAUL B. GODDARD, A.M.,M.D., Professor of Anatomy and Histology in the Franklin Medical College, Philadelphia. WITH OVER TWO HUNDRED ILLUSTRATIONS. Beautifully Printed from the Second London Edition, in One very neat Octavo Volume. “ Mr. Wilson, before the publication of this work, was very favorably known to the profession by his trea- tise on Practical and Surgical Anatomy; and, as this is the Second American Edition, from the second London Edition, since 1840, any special commendation of the high value of the present work, on our part, would be supererogatory. Besides, the work has been translated at Berlin, and overtures were repeatedly made to the London publisher for its reproduction in France. The work is, undoubtedly, a complete system of human anatomy, brought up to the present day. The illustrations are certainly very beautiful, the originals having been expressly designed and executed for this work by the celebrated Bagg of London; and, in the American edition they have been copied in a masterly and spirited manner. As a text-book in the various colleges we would commend it in the highest terms .” — New York Journal of Medicine. WILSON’S DISSECTOR. THE DISSECTOR; OR, PRACTICAL AND SURGICAL ANATOMY. BY ERASMUS WILSON, Author of “A System of Human Anatomy, &c. WITH ONE HUNDRED AND SIN ILLUSTRATIONS. MODIFIED AND RE-ARRANGED BY PAUL B. GODDARD, M. D., Professor of Anatomy and Histology in the Franklin Medical College, Philadelphia. In One Large Royal Duodecimo Volume, Sheep. “ It strikes us as being all that a “ Dissector” should be. The wood-cuts are numerous and will afford the student the most essential aid in the dissecting room.” — West. Journ. of Med. and Surg. WILSON ON THE SKIN. A PRACTICAL AND THEORETICAL TREATISE ON THE DIAGNOSIS, PATHOLOGY AND TREATMENT OF DISEASES OF THE SKIN; ARRANGED ACCORDING TO A NATURAL SYSTEM OF CLASSIFICATION, AND PRECEDED BY AN OUTLINE OF THE ANATOMY AND PHYSIOLOGY OF THE SKIN. BY ERASMUS WILSON, ' Lecturer on Anatomy and Physiology in the Middlesex Hospital Medical School, &c. &c. In One Neat Octavo Volume, Cloth. “ It is a sound book of practice. As a practical guide to the classification, diagnosis and treatment of the dis eases of the skin, the hook is complete. We know nothing, considered in this aspect, better in our language ; it is a safe authority in all the matters which, in this range of diseases, engage the practitioner’s attention, and possesses the high quality, unknown, we believe, to every older manual, of being on a level with Science’s high water mark . — Medical Times. LEA & BLANCHARD’S PUBLICATIONS. 21 A NEW AND COMPLETE WORK ON FEVERS. FEYEES; THEIR DIAGNOSIS, PATHOLOGY & TREATMENT. PREPARED AND EDITED WITH LARGE ADDITIONS, FROM THE ESSAYS ON FEVER IN TWEEDIE’S LIBRARY OF PRACTICAL MEDICINE, BY MEREDITH CLYMER, M. D, Professor of the Principles and Practice of Medicine in Franklin Medical College, Philadelphia ; Consulting Physician to the Philadelphia Hospital ; Fellow of the Col- lege of Physicians, fyc. |c. In one octavo volume of 600 pages. The want of a distinct treatise on Fevers, embodying the received doctrines of their pathology and treatment has long been felt and generally acknowledged. To supply this deficiency in medical literature is the object of the present volume. It has been prepared from the Essays on Fever contributed by Drs. Christison, Shapter, Burrows, Gregory and Locock, to Dr. Tweedie’s “ Library of Practical Medicine,” and will be found to embrace the whole class of Idiopathic Fevers, — Continued, Periodical, Eruptive, and Puerperal, The additions of the Editor, amounting to about one-half of the volume, have been chiefly made with reference to the Fevers of this country. It has been his aim to render the work as complete as possible, and to adapt it particularly to the necessities of the American Practitioner. WILLIAMS’ PATHOLOGY. PRINCIPLES OF MEDICINE, COMPRISING GENERAL PATHOLOGY AND THERAPEUTICS, AND A GENERAL VIEW OF ETIOLOGY, NOSOLOGY, SEMEIOLOGY, DIAGNOSIS AND PROGNOSIS. BY CHARLES J. B. WILLIAMS, M. D., F. R. S., Fellow of the Royal College of Physicians, &c. WITH NOTES AND ADDITIONS, BY MEREDITH CLYMER, M.D.,&c. In one volume, 8uo. WILLIAMS AND CLYMER ON THE CHEST, & c A TREATISE ON THE DISEASES OF THE RESPIRATORY {ORGANS, INCLUDING THE TRACHEA, LARYNX, LUNGS, AND PLEURA. BY CHARLES J. B. WILLIAMS, M.D., Consulting Physician to the Hospital for Consumption and Diseases of the Chest ; Author of “Principles of Medicine,” &c. &c. " WITH NUMEROUS ADDITIONS AND NOTES, BY MEREDITH CLYMER, M.D., &c. In one neat octavo volume, with cuts. This work recommends itself to the notice of the profession as containing a more particular and detailed account of the affections of which it treats than perhaps any other volume before the public. “The wood-cuts illustrating the physical exmination of the chest, are admirably executed, and the whole mechanical execution of the work does much credit to the publishers. This work is undoubtedly destined to take precedence of all others yet published on the ‘ Respiratory Organs,’ and as a text-book for teachers and students, no better in the present state of the science is to be expected/' — Ntu > York Journal of Medicim. 22 LEA & BLA CHARD’S PUBLICATIONS. KIRBY & SPENCE’S ENTOMOLOGY, FOR POPULAR USE, AN INTRODUCTION TO ENTOMOLOGY; OR, ELEMENTS OF THE NATURAL HISTORY OF INSECTS : COMPRISING AN ACCOUNT OF NOXIOUS AND USEFUL INSECTS, OF THEIR METAMORPHOSES, FOOD, STRATAGEMS, HABITATIONS, SOCIETIES, MOTIONS, NOISES, HYBERNATION, INSTINCT, &c., &c. With Plates. Plain or Colored. By WILLIAM KIRBY, M.A., F.R.S. And WILLIAM SPENCE, Esq., F.R.S. FROM THE SIXTH LONDON EDITION. Which was Corrected and Considerably Enlarged, In One Large Octavo Volume , extra cloth . This work, as il at present stands, is acknowledged to be the best extant as a popular introduction to the science, containing an immense amount of singular and interesting information, conveyed in a simple and agreeable manner. In preparing the. last edition, from which this is printed, the authors have omitted the two last volumes, as being too scientific for popular use, and arranged it as it now is, forming a complete exposi tiou of the principles of the study, unincumbered with Anatomical or scientific details. “We are well aware that the physician engaged in an engrossing practice, whether in town or country, has not much leisure for the perusal of books unconnected with his profession ; but we know just as well, that while the few are thus immersed in business, the many have the command of more time than they are disposed to give to professional reading. How many are the hours wasted by nearly every young physician, waiting for practice — anxious, dreary hours, because unoccupied ! Why not spend these hours in the study of such works as that of Kirby & Spence, wherein the physiologist, farmer, horticulturist, philosopher, and moralist, may find matter to instruct him . — The Western Journal of Medicine and Surgery. “The republication of this work, which has for many years enjoyed a very high and constantly increasing popularity in Great Britain, confers a decided benefit upon natural science in this country. It is a free, careful and authentic exposition of the very extensive department of study, of which it treats, and has done much abroad to attract attention to a branch which, until its publication, has found comparatively little favor with the scientific students of Great Britain. The treatise of Messrs. Kirby & Spence is well adapted, not only by its intrinsic merit, but by its attractive style, to introduce the subject to popular favor. It is thrown into the form of letters, and although abounding to some extent in scientific terms, it is divested of technicality so far as pos- sible, and by a very agreeable intermixture of anecdotes. &c.. is made a pleasant and entertaining, as well as very instructive and important work. It is now reprinted from the sixth London edition, which has been revised and corrected, and forms a very handsome octavo volume of about GOO pages. Those who have never given any attention to the subject of which it treats, will find embodied in it an immense amount of very inte- resting and useful information, set forth in an agreeable and attractive style.” — N. Y. Courier and Enquirer. THE CHEMISTRY OF THE FOUR SEASONS, BY THOMAS GRIFFITH, Lecturer on Chemistry at St. Bartholomew’s Hospital, &c. &c. IN ONE VERY NEAT DUODECIMO VOLUME. With Numerous Wood- cuts. A New Work. The object of this little book is to show in a popular and agreeable manner the chemical agency exerted in the various phenomena of nature. It forms a neat volume for the Centre Table. A TEXT BOOK OF PRACTICAL GEOLOGY AND MINERALOGY. WITH INSTRUCTIONS FOR THE QUALITATIVE ANALYSIS OF MINERALS, BY JOSHUA TRIMMER, F. G. S. WITH TWO HUNDRED AND TWELVE WOOD-CUTS. A handsome octavo volume, bound in embossed cloth. This is a systematic introduction to Mineralogy, and Geology, admirably calculated to instruct the student in those sciences. The organic remains of the various formations are well illustrated by numerous hgures, which are drawn with great accuracy. LEA & BLANCHARD’S PUBLICATIONS. 23 GRAHAM’S CHEMISTRY., THE ELEMENTS OF CHEMISTRY. INCLUDING THE APPLICATION OF THE SCIENCE TO THE ARTS. With Numerous Illustrations. BY THOMAS GRAHAM, F. R. S. L. and E. D. Professor of Chemistry in University College. London, &c. &e. WITH NOTES AND ADDITIONS, BY ROBERT BRIDGES, M.D., &c. &c, In One Volume Octavo. The great advancement recently made in all branches of chemical investigation, renders neces- sary an enlarged work which shall clearly elucidate the numerous discoveries, especially in the department connected with organic Chemistry and Physiology, in which such gigantic strides have been made during the last few years. The present treatise is considered by eminent judges to fulfil these indications, and to be peculiarly adapted to the necessities of the advanced medical student and practitioner. In adapting it to the wants of the American profession, the editor has endeavored to render his portion of the work worthy the exalted reputation of the first chemist ot England. It is already introduced in many of the Colleges, and has universal approbation. FOWNES’S CHEMISTRY FOR STUDENTS. ELEMENTARY CHEMISTRY, THEORETICAL AND PRACTICAL. By GEORGE FOWNES, Ph. D., Chemical Lecturer in the Middlesex Hospital Medical School, &c. &c. With Numerous Illustrations. Edited, with Additions, By ROBERT BRIDGES, M. D., Professor of General and Pharmaceutical Chemistry in the Philadelphia College ol Pharmacy, &c. &c. In one large duodecimo volume, sheep or extra cloth. The character of this work is such as to recommend it to all colleges in want of an elementary text-book, and to all practitioners who wish to place a compendious manual in the hands of their students. It is fully brought up to the day, containing all the late views and discoveries that have so entirely changed the face of the science, and it is completely illustrated with very numerous wood engravings explanatory of all the different processes and forms of apparatus. Though strictly scientific, it is written with great clearness and simplicity of style, rendering it easy to be mastered by those commencing the study. The low price at which it is sold, places it within the reach of all. Though this work has been so recently published, it has already been adopted as a text-book by many of the Medical Institutions throughout the country. As a work for the first class student, and as an introduction to the larger systems of Chemistry, such as Graham’s, there has been but one opinion expressed concerning it, and it may now be considered as THE TEXT-BOOK EOR THE CHEMICAL STUDENT. SIMON’S CHEMISTRY OF MAN. ANIMAL CHEMISTRY. WITH REFERENCE TO THE PHYSIOLOGY & PATHOLOGY OF MAN. BY DR. J. FRANZ SIMON. TRANSLATED AND EDITED BY GEORGE E. DAY, M. A. & L. M. Cantab., &c. With plates. In one octavo volume , of over seven hundred pages, sheep, or in two parts, boards . This important work is now complete and may be had in one large octavo volume. Those who obtained the first part can procure the second separate. “ No treatise on physiological chemistry approaches, in fulness and accuracy of detail, the work which stands at the head of this article. It is the production of a man of true German assiduity, who has added to his own researches the results of the labors of nearly every other inquirer in this interesting branch of science. — The death of such a laborer, which is mentioned in the preface to the work as having occurred prematurely in 1S42, is indeed a calamity to science. He had hardly reached the middle term of life, and yet had made himself known all over Europe, and in our country, where his name has been familiar for several years as amon» the most successful of the cultivators of the Chemistry of Man It is a vast repository of facts, to which the teacher aud student may refer with equal satisfaction.”— The Western Journal of Medicine and Surgery, :4 LEA «Si BLANCHARD’S PUBLICATIONS. WATSON’S PRACTICE OF PHYSIC. New Edition by Condie. LECTURES ON THE PRINCIPLES AND PRACTICE OF PHYSIC. DELIVERED AT KING’S COLLEGE, LONDON. BY THOMAS WATSON, M. D., &c. &c. Second American, from the Second London Edition, REVISED, WITH ADDITIONS, BY D. FRANCIS CONDIE, M. D., Author of a work on the “ Diseases of Children,” &c. In one Octavo Volume, Of nearly ELEVEN HUNDRED Large Pages, strongly bound with raised bands. c< We know of no work better calculated for being placed in the hands of the student, and for a text-book, and as such we are sure it will be very extensively adopted. On every important point tiie author seems to have posted up his knowledge to the day .” — American Medical Journal. The rapid sale of the first edition of this work is an evidence of its merits, and of its general favor with the American practitioner. To commend it still more strongly to the profession, the publishers have gone to a great expense in preparing this edition with larger type, finer paper, and stronger binding, with raised bands. It is edited with reference particularly to American practice, by Dr. Condie; and with these numerous improvements, the price is still kept so low as to be within the reach of all, and to render it among the cheapest works offered to the profession. It has been received with the utmost favor by the medical press, both of this country and of England, a few of the notices of which, together with a letter from Professor Chapman, will be found in the Supple- ment to The Medical News and Library, for November, 1845. A NEW AND IMPROVED EDITION OF RAMSBOTHAM’S STANDARD WORK ON PARTURITION. THE PRINCIPLES AND PRACTICE OF OBSTETRIC MEDICINE AND SURGERY, IN REFERENCE TO THE PROCESS OF PARTURITION. ILLUSTRATED BY One hundred and forty-eight Large Figures on 55 Lithographic Plates, BY FRANCIS H. RAMSBOTHAM, M. D., &c. A NEW EDITION, FROM THE ENLARGED AND REVISED LONDON EDITION. In one large imperial octavo volume, well bound. The present edition of this standard work will be found to contain numerous and important improvements over the last. Besides much additional matter, there are several more plates and wood-cuts, and those which were before used have been re-drawn. This book has long been known to the profession, by whom it has been most flatteringly received. A more extended advertisement, with a recommendatory letterfrom Professor .Hodge of the University of Pennsylvania, may be seen in the November Supplement to The Medical News. CONDIE ON CHILDREN. A PRACTICAL TREATISE ON THE DISEASES OF CHILDREN, BY D. FRANCIS CONDIE, M. D., Fellow of the College of Physicians; Member of the American Philosophical Society, &c. See. IN ONE VOLUME, OCTAVO. fry* The Publishers would particularly call the attention of the Profession to an examination of this work. “Dr. Condie, from the very great labor which he has evidently bestowed upon this book, is entitled to ou r respect as an indefatigable and conscientious student; but if we consider the results of his labor, we cannot but admit his claim to a place in the very first rank of eminent writers on the practice of medicine. Regard- ing his treatise as a whole, it is more complete and accurate in its descriptions, while it is more copious and more judicious in its therapeutical precepts than any of Us predecessors, and we feel persuaded that the Ame- rican medical profession will very soon regard it, not only as a very good, but as the very best ‘ Practica Treatise on the Diseases of Children.’ ” — Am. Med. Journal. LEA & BLANCHARD’S- PUBLICATIONS. 25 THE SURGICAL WORKS OF SIR ASTLEY COOPER, LEA & BLANCHARD have how completed the last volume of the illustrated works of Sir Astley Cooper. They form an elegant series; the works on Hernia, the Testis, the Thymus Gland and the Breast, being printed, illustrated and hound to match, in imperial octavo with numerous LITHOGRAPHIC PLATES, while the Treatise on Dislocations is in a neat medium octavo form, with NUMEROUS WOOD CUTS similar to the last London edition. SIR ASTLEY COOPER ON HERNIA, With One Hundred and Thirty Fig ures in Lithography. THE ANATOMY AND SURGICAL TREATMENT OF ABDOMINAL HERNIA. By Sir ASTLEY COOPER, Bart. Edited by C. Aston Key, Surgeon to Guy’s Hospital, &c. This important work of Sir Astley is printed from the authorized second edition, published in London, in large snper-royal folio, and edited by his nephew. Professor Key. It contains all the Plates and all the Letterpress — there are no omissions, interpolations, or modifications — it is the complete work in One Large Imperial Octavo Volume. With over 130 Figures on 26 Plates, and over 400 Large Pages of Letterpress. The correctness of the Plates is guaranteed by a revision and close examination under the eye of a distin- guished Surgeun of this city. ANOTHER VOLUME OF THE SERIES CONTAINS HIS TREATISE ON THE STRUCTURE AND DISEASES OF THE TESTIS. Illustrated by U0 Figures. From the Second London Edition. BY BRANSBY B. COOPER, ESQ. AND ALSO ON THE ANATOMY OF THE THYMUS GLAND. Illustrated by 51 Figures . The two works together in one beautiful imperial octavo volume, illustrated with twenty-nine plates in the best style of lithography, and printed and bound to match. The Series is concluded by COOPER ON THE ANATOMY AND DISEASES OF THE BREAST, &>., This large and beautiful volume contains THE ANATOMY OF THE BREAST: THE COMPARATIVE ANATOMY OF THE MAMMARY GLANDS: ILLUSTRATIONS OF THE DISEASES OF THE BREAST; And Twenty-five Miscellaneous Surgical Papers, now first published in a collected form. Br Sir ASTLEY COOPER, Bart., F. R. S., &c. The whole in one large imperial octavo volume, illustrated with two hundred and fifty-two figures on thirty six Lithographic Plates ; well and strongly bound. COOPER ON FRACTURES AND DISLOCATIONS, WITH NUMEROUS WOOD-CUTS. A TREATISE ON DISLOCATIONS AND FRACTURES OF THE JOINTS. By Sir ASTLEY COOPER, Bart., F. R. S., Sergeant Surgeon to the King, &c. A NEW EDITION MUCH ENLARGED ; Edited by BRANSBY COOPER, F. R. S., Surgeon to Guy’s Hospital. WITH ADDITIONAL OBSERVATIONS FROM Professor JOHN C. WARREN, of Boston. With numerous engravings on wood , after desig?is by Bagg , a memoir and a splendid portrait of Sir Astley. In one octavo volume. The peculiar value of this, as of all of Sir Astley Cooper’s works, consists in its eminently practical charac- ter. His nephew, Bransby B. Cooper, from his own experience, has added a number of cases. Besides this, Sir Astley lefi behind him very considerable additions in MS. for the express purpose of being introduced into this edition. The volume is embellished with ONE HUNDRED AND THIRTY-THREE WOOD-CUTS, and contains the history of no less than three hundred and sixty-one cases, thus embodying the records of a life of practice of the Author and his various editors. There are also additional Observations from notes fur- nished by John C. Warren, M. D., the Professor of Anatomy and Surgery in Harvard University. “ After the fiat of the profession, ii would be absurd in us to eulogize Sir Astley Cooper’s Work on Fracturea and Dislocations. It is a national one, and will probably subsist as long as English Surgery,” — Medico-Chi- rurgical Review. 26 LEA & BLANCHARD’S PUBLICATIONS. A NEW MEDICAL DICTIONARY, In one Volume, large 12mo., now ready, at a low price, A DICTIONARY OF THE TERMS USED IN MEDICINE AND THE COLLATERAL SCIENCES; By RICHARD D. HOBLYN, A.M., Oxon. FIRST AMERICAN, FROM THE SECOND LONDON EDITION. REVISED, WITH NUMEROUS ADDITIONS, By ISAAC HAYS, M. D., Editor of the American Journal of the Medical Sciences. Believing that a work of this kind would be useful to the profession in this country, the publishers have issued an edition in a neat form for the office table, at a low price. Its object is to serve as an introduction to the larger and more elaborate Dictionaries, and to assist the student commencing the study of Medicine, by presenting in a concise form an explanation of the terms most used in Medicine and the Collateral Sciences, by giving the etymology and definition in a manner as simple and clear as possible, without going into details ; and bringing up the work to the present time by including the numerous terms lately introduced. This design the author has so ably executed as to elicit the highest encomiums of the medical press. It has been edited with especial reference to the wants of the American practitioner, the native medicinal plants being introduced, with the formulae for the various officinal preparations : and the whole being made to conform to the Pharmacopoeia of the United States. It is now ready in one neat royal duodecimo volume of four hundred pages in double columns. TAYLOR’S MEDICAL JURISPRUDENCE. MEDICAL JURISPRUDENCE. By ALFRED S. TAYLOR, Lecturer on Medical Jurisprudence and ChemiBtry at Guy’s Hospital, &c. With Numerous Notes and Additions, and references to American Practice and Law. Br R. E. GRIFFITH, M. D. In one volume, 8vo. “ We recommend Mr. Taylor’s work as the ablest, most comprehensive, and, above all, the most practically "Useful book which exists on the subject of legal medicine. Any man of sound judgment, who has mastered the contents of Taylor’s 1 Medical Jurisprudence,’ may go into a court of law with the most perfect confidence of being able to acquit himself creditably.” — Medico-Chirurgical Review. “ As we expected, it has become truly the manual of both the medical and legal professions, and is regarded by all as the standard authority on the subject; the author, also, as we find from the public prints, is the person consulted, almost as a matter of course, in the more difficult medico- legal cases. — The British and Foreign Medical Review. LAWRENCE ON THE EYE. New Edition— Now Ready. A TREATISE ON THE DISEASES OF THE EYE. BY W. LAWRENCE, F, R. 8., Surgeon Extraordinary to the Queen, Surgeon to St. Bartholomew’s Hospital, & c. &c. SECOND AMERICAN, FROM THE LAST LONDON EDITION, With many Modifications and Additions, and the Introduction of over one hundred Illustrations, BY ISAAC HAYS, M. D., Surgeon to Will’s Hospital, Physician to the Philadelphia Orphan Asylum, See. Sec. IN ONE LARGE OCTAVO VOLUME. The character of this work is too well known to require a word of commendation. It is justly considered the best we possess on the subject. In this edition will be found many important alterations and improvements, bringing the work up to the level of the present state of knowledge on the subjects of Ophthalmic Surgery and Practice. The chapters on the Anatomy and Physiology of the Organ have received especial augmentations; and many new cuts have been introduced, rendering the whole clear and comprehensible. LEA & BLANCHARD’S PUBLICATIONS. 27 MILLER’S SURGICAL WORKS. THE PRINCIPLES OF SURGERY. BY JAMES MILLER, F. R. S.E., F.R. C.S. E., Professor of Surgery in the University of Edinburgh, &c. In one neat octavo volume, to match the Author's volume on “ Practice .” “ No one can peruse this work without the conviction that he has been addressed by an accom- plished surgeon, endowed with no mean literary skill or doubtful good sense, and who knows how to grace or illumine his subjects with the later lights of our rapidly advancing physiology. The book deserves a strong recommendation, and must secure itself a general perusal.” — Medical Times. “ We feel no hesitation in expressing our opinion that it presents the philosophy of the science more fully and clearly than any other work in the language with which we are acquainted.” — Phi- ladelphia Medical Examiner. “ To the student who wishes to acquire a useful practical knowledge of the pathology of sur- gical diseases, it is impossible to recommend abetter guide than the present treatise by Mr. Mil- ler.” — Edinburgh Medical and Surgical Journal. “ An admirable epitome of the surgical science of the day. Being written by a sound practical surgeon accustomed to the public teaching of his science, it has the clearness of diction and ar- rangement which renders it an excellent manual for the students as well as that amount of scien- tific and practical information which makes it a safe and valuable guide to the practitioner.” — The Lancet. JUST PUBLISHED. THE PRACTICE OF SURGERY. BY JAMES MILLER. Professor of Surgery in the University of Edinburgh. In one neat octavo volume. This work is printed and bound to match the “ Principles of Surgery,” by Professor Miller,'lately issued by L. & B. Either volume may be had separately. “ This work, with the preceding one, forms a complete text-book of surgery, and has been under- taken by the author at the request of his pupils. Although, as we are modestly informed in the preface, it is not put forth in rivalry of the excellent works on practical surgery which already exist, we think we may take upon ourselves to say, that it will form a very successful and formidable rival to most of them. While it does not offer the same attractive illustrations, with which some of our recent text-books have been embellished, and while it will not, as indeed is not its design, set aside the more complete and elaborate works of reference which the profession is in possession of, we have no hesitation in stating that the two volumes form, together, a more complete text-book of surgery than any one that has been heretofore offered to the student.” — The Northern Journal qf Medicine. “ Mr. Miller is already known in his profession as an able writer and a well informed surgeon, and the book before us is calculated to maintain his reputation. We recommend it to those who want a sound guide, or wish to refresh their recollections. The characteristics which especially distinguish the work are, its plain good sense, or the selection of the important from the unimport- ant announcements in surgery ; the sound indications of the judgment to be exercised in the treat- ment of surgical diseases.” — The Lancet. A NEW AND IMPROVED EDITION OF FERGUSSON’S OPERATIVE SURGERY. A SYSTEM OF PRACTICAL SURGERY, BY WILLIAM FERGUSSON, F.R. S.E. SECOND AMERICAN EDITION, REVISED AND IMPROVED. With Two Hundred and Fifty-two Illustrations from Drawings by Bagg, Engraved by Gilbert, With Notes and Additional Illustrations, BY GEORGE W. NORRIS, M. D,, &c. In one beautiful octavo volume of six hundred and forty large pages. • 11 If we weTe to say that this volume by Mr. Fergusson, is one excellently adapted to the student, and the yet inexperienced practitioner of surgery, we should restrict unduly its range. It isofthe kind which every medi- cal man ought to have by him for ready reference, as a guide to the prompt treatment of many accidents and injuries, which whilst he hesitates, may be followed by incurable defects, and deformities of structure, if not by death itself. In drawing to a close our notice of Mr. Fergusson’s Practical Surgery, we cannot refrain from again adverting to the numerous and beautiful illustrations by wood-cuts, which contribute so admirably to elucidate the descriptions in the text. Dr. Norris has, as usual, acquitted himself judiciously in his office of annotator. His additions are strictly practical and to the point .”— Bulletin of Medical Science. 2 $ LEA & BLANCHARD’S PUBLICATIONS, LIBRARY OF SURGERY. CHELIUS’S SYSTEM OF SURGERY. A SYSTEM OF SURGERY. By J. M. CHELIUS, Doctor in Medicine and Surgery, Public Professor of General and Ophthalmic Surgery, etc. etc. in the University of Heidelberg. TRANSLATED FROM THE GERMAN, AND ACCOMPANIED WITH ADDITIONAL NOTES AND OBSERVATIONS, By JOHN F. SOUTH, SURGEON TO ST. THOMAS'S HOSPITAL. EDITED, WITH REFERENCE TO AMERICAN AUTHORITIES, By GEORGE W. NORRIS ; M.D. Publishing in Numbers, at Fifty Cents each. Nine Numbers are now ready: and the whole is expected to be complete by September next, forming Three Large Octavo Volumes. That this work should have passed to six editions in Germany, and have been translated into no less than seven languages, is sufficient proof of its value. It contains what is, perhaps, embraced to an equal extent by no other work on the subject now before the public— a complete System of Surgery, both in its principles and practice. The additions of the translator, Mr. South, are very numerous, bringing the work up to the very day of publication, and embodying whatever may have been omitted by the author respecting English Sur- gery; while Dr. Norris will take equal care in representing the state of the Science in America. “Judging from a single number only of this work, we have no hesitation in saying that, if the remaining por- tions correspond at all with the first, it will be by far the most complete and scientific System of Surgery in the English language. We have, indeed, seen no work which so nearly comes up to our idea of what such a pro- duction should be, both as a practical guide and as a work of reference, as this; and the fact that it has passed through six editions in Germany, and been translated into seven languages, is sufficiently convincing proof of its value. It is methodical and concise, clear and accurate; omitting all minor details and fruitless speculations, it gives us all the information we want in the shortest and simplest form The New York Journal of Medicine. “The scope of Professor Chelius’s Manual is indicated by its title: it professes to treat, systematically, of the science and art of Surgery, but within such compass as to render the work an appropriate introduction and companion to his lectures. The care, however, which has been bestowed upon its construction, and the labor which its research evinces, would be ill repaid were it confined to this sphere; and we may conscientiously say, that we know of no Manual of Surgery, on the whole, more deserving of public confidence, or more vali> able as a guide and refresher to the young practitioner. It is not our intention at present critically to analyze Mr. South’s labors; but we should be guilty of an injustice to him and to our readers if we did not cordially recommend his work as having fair promise of forming, what it is the translator’s ambition it should be, a sound and comprehensive system of Practical Surgery. The notes and text are so intermingled as to render it con- tinuously readable, without presenting those abrupt transitions which are so disagreeable in many works simi- larly arranged. The faults of omission, &c., at which we have hinted in our comments on the first chapter of our author's work, (viz. that on ‘ Inflammation ’) have been amply compensated by the copious and excellent digest of his translator and annotator who is justly proud of availing himself of the labors of our own coun- trymen in this department of pathology, while he gives their due meed of notice and respect to the contributions of our continental brethren. The references which are given to original works have evidently been carefully collated, and will be found of great value to the student and practitioner who may wish for more copious in- formation on any particular branch of Surgery; and the practical remarks and illustrations with which the work abounds, are a good guarantee of the translator’s ability to do justice to his task, at the same time that they prove that Mr. South has not failed to avail himself industriously of the large opportunities which his Hos- pital appointment has affdrded him.” — The British and Foreign Medical Review. “ We will, therefore, content ourselves for the present with directing the attention of the profession to it, as being the most complete system of Surgery in any language, and one that is of equal utility as a practical guide and as a work of reference. The fact of its having reached six editions in Germany, and its having been trans- lated into seven languages,.are more convincing proofs of its value than anything that we can say. Mr. South has performed his task with much judgment, and has certainly made a most useful addition to the medical lite- rature of this country by rendering Chelius’s work into English The Lancet. “ This work has long been the chief text-book on Surgery in the principal schools of Germany, and the pub- lication of five editions of it in the original and of translations into no less than eight foreign languages, show the high estimation in which it is held. As a systematic work on Surgery it has merits of a high order. It is methodical and concise— and on the whole clear and accurate. The most necessary information is conveyed in the shortest and simplest form. Minor details and fruitless speculations are avoided. It is, in fact, essen- { tially a practical book. This work was first published nearly twenty years ago. and its solid and permanent j reputation has no doubt led Mr. ^outh to undertake the present translation of the latest edition of it, which, we ,| are informed, is still passing through the press in Germany. We should have felt at a loss to select any one better qualified for the task than the translator of Otto*s Compendium of Human and Comparative Pathological | Anatomy — a surgeon to a large hospital, whose industry and opportunities have enabled him to keep pace with | the improvements of his time.” — The Medico- Chirurgical Review. “Although Great Britain can boast of some of the most skilful surgeons, both among her past and her present I professors of that branch of medical science, no work professing to be a complete system of Surgery has been | published in the British dominions since that of Benjamin Bell, now more than half a century old. “This omission in English medical literature is fully and saiisfactorily supplied by the translation of Professor | Chelius’s System of Surgery by a gentleman excellently fitted for the task, both by his extensive reading, and | the opportunities of practical experience which he has enjoyed for years as surgeon to one of our largest me- j tropolitan hospitals. The fact ot Professor Chelius’s work having been translated into seven languages is suf- ; ficient proof of the estimation in which it is held by our continental brethren, and the English edition, now in i course of publication, loses none of the value of the original from the treatment received at the hands of its I translator. The notes and additions of Professor South are numerous, and contain the opinions resulting from I his vast experience, and from that of his colleague. “ We are free to confess, prejudiced though perhaps we are, in favor of the English practice of surgery, that j ®his work is one of great value, and one which every practitioner and advanced student should possess.” — The j Medical Times. WORKS IN VARIOUS DEPARTMENTS OF MEDICINE AND SURGERY, PUBLISHED BY LEA & BLANCHARD. AMERICAN JOURNAL OF THE MEDICAL SCIENCES. Edited by Isaac Hays, M. D. Published quarterly at §5 00 per annum. ANDRAL ON THE BLOOD. Pathological Haematology ; an Essay on the Blood in Dis- ease. Translated by J. F. Meigs and Alfred Stille. In one octavo volume, cloth. ARNOTT’S PHYSICS. The Elements of Physics in plain or non-technical language. A New Edition. Edited by Isaac Hays, M. D. In 1 vol. 8vo., sheep, with 176 wood-cuts. ABERCROMBIE ON THE STOMACH. Pathological and Practical Researches on Dis- eases of the Stomach, Intestinal Canal, &c. Fourth Edition. In 1 vol. 8vo., sheep. ABERCROMBIE ON THE BRAIN. Pathological and Practical Researches on the Dis- eases of the Brain and Spinal Cord. A New Edition. In one octavo volume, sheep. ALISON'S PATHOLOGY. Outlines of Pathology and Practice of Medicine. In three parts, containing Preliminary Observations, Inflammatory and Febrile Diseases, and Chronic or Non-Febrile Diseases. In one neat octavo volume, sheep. BIRD ON URINARY DEPOSITS. Urinary Deposits, their Diagnosis, Pathology and The- rapeutical Indications. In one neat octavo volume, cloth, with numerous wood-cuts. BERZELIUS ON THE KIDNEYS AND URINE, in 1 vol. 8vo., cloth. BUCKLAND’S GEOLOGY. Geology and Mineralogy, with reference to Natural Theology. A Bridgewater Treatise. In two octavo volumes, with numerous maps, plates, &c. BRIDGEWATER TREATISES. The whole complete in 7 vols. 8vo., containing Roget’s Animal and Vegetable Physiology, in 2 vols., with many cuts; Kirby on the History, Habits and Instinct of Animals, 1 vol. with plates ; Prout on Chemistry ; Chalmers on the Moral Condition of Man ; Whewell on Astronomy ; Bell on the Hand ; Kidd on the Phy- sical Condition of Man; and Buckland’s Geology, 2 vols., with many plates and maps. BARTLETT ON FEVERS OF U. S. The History, Diagnosis and Treatment of Typhus and Typhoid Fevers, and on Bilious Remittent and Yellow Fever. In L vol. 8vo., ex. cloth. BARTLETT’S PHILOSOPHY OF MEDICINE. Essay on the Philosophy of Medical Science. In two Parts. One neat octavo volume, extra cloth. BRIGHAM ON MIND, &c. The Influence of Mental Excitement and Mental Cultivation on Health. In one neat 12mo. volume, extra cloth. BILLING’S PRINCIPLES OF MEDICINE. The First Principles of Medicine. From the Fourth London Edition. In one octavo volume, cloth. CHITTY’S MEDICAL JURISPRUDENCE. A Practical Treatise on Medical Jurispru- dence. With Explanatory Plates. In one octavo volume, sheep. CLATER AND SKINNER’S FARRIER. Every Man his own Farrier. Containing, the Causes, Symptoms, and most approved Methods of Cure of the Diseases of Horses. — From the 28th London Edition. Edited by Skinner. In one 12mo. volume, cloth. CLATER AND YOUATT’S CATTLE DOCTOR. Every Man his own Cattle Doctor— Containing the Diseases of Oxen, Sheep, Swine, &c. Edited by Youatt, and revised by Skinner. With Wood-cuts. In one volume 12mo. DURLACHER ON CORNS, BUNIONS, &c. A Treatise on Corns, Bunions, the Dis- eases of Nails, and the General Management of the Feet. In one 12mo. volume, cloth. ELLIOTSON’S MESMERIC CASES. In one octavo pamphlet. ESQUIROL ON INSANITY. Mental Maladies, Considered in Relation to Medicine, Hy- giene and Medical Jurisprudence. Translated by E. IC. Hunt, M. D., &e. In 1 vol. 8vo. GUTHRIE ON THE BLADDER, &c. The Anatomy of the Bladder and Urethra, and the Treatment of the Obstructions to which those passages are liable. In I vol. 8vo, HARRIS ON MAXILLARY SINUS. Dissertation on the Diseases of the Maxillary Sinus. In one small octavo volume, cloth. 29 30 LEA & BLANCHARD’S PUBLICATIONS. KIRBY ON ANIMALS. The History, Habits and Instinct of Animals. A Bridgewater Treatise. In one large volume 8vo. with plates. HARRISON ON THE NERVES. An Essay towards a correct Theory of the Nervous System. In one octavo volume, sheep. LAWRENCE ON RUPTURES. A Treatise on Ruptures, from the fifth London Edition. In one octavo volume, sheep. MAURY’S DENTAL SURGERY. A Treatise on the Dental Art, founded on Actual Ex- perience. Illustrated by 241 Lithographic Figures and 54 Wood-cuts. Translated by J. B. Savier. In one octavo volume, sheep. MULLER’S PHYSIOLOGY. Elements of Physiology. Translated by Wm. Baly, M.D., and edited and arranged by John Bell, M. D. In one large octavo volume, sheep. PROUT ON THE STOMACH. On the Nature and Treatment of Stomach and Renal Diseases. In one octavo volume, sheep, with colored plates. POPULAR MEDICINE, BY COATES. In one octavo volume, sheep, with Wood-cuts. PHILIP ON INDIGESTION. A Treatise on Protracted Indigestion. In 1 vol. 8vo. ROGET’S PHYSIOLOGY. A Treatise on Animal and Vegetable Physiology, with over 400 illustrations on Wood. In two octavo volumes, cloth. A Bridgewater Treatise. ROGET’S OUTLINES OF PHYSIOLOGY. Outlines of Physiology and Phrenology. In one large octavo volume, cloth. RIGBY’S MIDWIFERY. A System of Midwifery. With Wood-cuts. In 1 vol. 8vo. RICORD ON VENEREAL. A Practical Treatise on Venereal Diseases ; with a Thera- peutical Summary, and a Special Formulary. In I vol. 8vo., cloth. ROBERTSON ON TEETH. A Practical Treatise on the Human Teeth, with plates. One. small volume octavo, cloth. TRAILL’S MEDICAL JURISPRUDENCE. Outlines of a Course of Lectures on Medi- cal Jurisprudence. Revised, with numerous notes. In one octavo volume, cloth. THOMSON’S SICK ROOM. Domestic Management of the Sick Room, Necessary in Aid of Medical Treatment, for the Cure of Diseases. Edited by R. E. Griffith, M. D. In one large royal 12mo. volume, extra cloth, with Wood-cuts. WALSHE ON THE LUNGS. Physical Diagnosis of the Diseases of the Lungs. In one neat 12mo. volume, extra cloth. YOUATT ON THE HORSE. The Horse: containing a full account of the Diseases of the Horse, with their mode of Treatment; his Anatomy, and the usual Operations per- formed on him; his Breeding, Breaking, and Management; and Hints on his Sound- ness, and Purchase and Sale. Together with a General History of the Horse ; a Dis- sertation on the American Trotting Horse, how trained and jockeyed, an account of his remarkable performances; and an Essay on the Ass and the Mule. By J. S. Skinner, Assistant Postmaster General, and Editor of the Turf Register. In one volume, octavo, with numerous Cuts. jnEDICJlli WORKS, at Press and Preparing. A MANUAL OF MATERIA MEDICA AND Therapeutics. By J. Forbes Royle, M. D., &c. Edited by J. Carson, M. D., &c. In 1 vol. 8vo., numerous wood-cuts, ( nearly ready). TODD & BOWMAN’S PHYSIOLOGICAL ANA- tomy and Physiology ofMan. Many wood-cuts, ( publishing in the Medical News and Library ). A TREATISE ON OPHTHALMIC MEDICINE and Surgery. By T. Wharton Jones. In lvol. beautifully illustrated. PRINCIPLES OF GENERAL AND COMPA- rative Physiology. By Wm. B. Carpenter, M. D.,&c. From a new London edition, with numerous improvements and additions. In 1 vol. large 8vo., many steel plates. A TREATISE ON ANIMAL PHYSIOLOGY, with very numerous illustrations. By Wm. B. Carpenter. — To be followed by his other works on Natural Science. A NEW AMERICAN FORMULARY. By J. Carson, M. D., &c. In one volume, (preparing). A SYSTEM OF SURGERY. By J. M. Chelius. Translated by South, and Edited by Norris. — Publishing in numbers at 50 cents each. To be complete in three octavo volumes. HORNER’S AMERICAN DISSECTOR, in one large 12mo. vol., with many cuts, (nearly ready.) AN ANATOMICAL DESCRIPTION OF THE Diseases of the Organs of Circulation and Re- spiration. By C. E. Hasse. Translated and Edited by W. E. Swaine, M. D., &c. In 1 vol. 8vo., (nearly ready). A TREATISE ON AURAL SURGERY. In 1 vol. 8vo., many illustrations. A COMPLETE MEDICAL BOTANY, especially adapted to the United States. By R. E. Grif- fith, M. D. In 1 vol. large 8vo., with many illustrations. LECTURES ILLUSTRATIVE OF VARIOUS Subjects in Pathology and Surgery. By Sir B. Brodie — completing his works. CALORIC, its Mechanical, Chemical, and Vital Agencies in the Phenomena of Nature. By S. L. Metcalfe, M. D., &c. In 1 large 8vo. vol. GOLDING BIRD’S ELEMENTS OF NATU- RAL PHILOSOPHY. With numerous wood- cuts. VOGEL’S PATHOLOGICAL ANATOMY.— Translated and Edited by G. Day, M. D., &c. In 1 vol. large 8vo., many plates. BURROWS ON CEREBRAL CIRCULATION, with plates. Together with other JVew Works. LEA & BLANCHARD’S PUBLICATIONS. 31 (See Page 33.) THE MEDICO-CHIRURGICAL REVIEW, EDINBURGH MEDICAL AND SURGICAL JOURNAL, AND NUMEROUS OTHERS. WHILE FROM FRANCE THE GAZETTE MEDIC ALE DE PARIS— L’EXPERIENCE— REVUE MEDIC ALE —JOURNAL DE MEDECINE— JOURNAL DES CONNAISSANCES MEDICO-CHIRURGICALES, AND VARIOUS OTHERS, WITH THE ZEITSCHRIFT FUR DIE GESAMMTE MEDICIN, WITH SEVERAL OTHERS FROM GERMANY , AND THE BIBLIOTHEK FOR LH3GER, OF DENMARK, TOGETHER WITH Alii* THE AMERICAST JOURCTAX.S, ARE PUT IN REQUISITION. It will thus be seen that the material for a full Summary of all NEW MATTERS AND IMPORTANT DISCOVERIES is full and ample, while the exertions of the Editor and the time of publication insure a fulness and newness to this department. ALL THE LATE AND IMPORTANT AMERICAN INTELLIGENCE, is fully recorded— while THE MOATMLY MEWS furnishes the lighter and floating information, and embraces important Books for THE LIBRARY DEPARTMENT. Among those works already published in the Monthly Library and News, may be mentioned WATSON’S LECTURES ON THE PRACTICE OP PHYSIC, AS ALSO BRODIE’S LECTURES ON SURGERY, CONCLUDED IN MARCH OF THIS YEAR, (1846). The work for the year 1S46 is a new one, TODD & BOWMAN’S PHYSIOLOGICAL ANATOMY & PHYSIOLOGY OF MAN, NOW PUBLISHING IN ENGLAND. This work has already earned for its authors a high reputation in Europe and this country. It will be reproduced entire, with all the numerous and beautiful wood-cuts. Each Work in the Library is regularly paged so as to be bound separately. THE TERMS ARE For the Medical Journal and the Medical News, if paid for by the first of February of each Year, and the amount remitted free of cost to the Publishers, ----- Five Dollars. For the Journal only, when ordered without funds, or paid for after the first of February of each year, - - - Five Dollars. For the Medical News only, to be paid for always in advance, and free of postage, ------- One Dollar. In no case can the News be sent without pay in advance. =#§ 32 TWO MEDICAL PERIODICALS FOR FIVE DOLLARS A YEAR. AMERICAN JOURNAL OF THE MEDICAL SCIENCES, Edited by ISAAC HAYS, M. D. SURGEON TO WILLS’ HOSPITAL, ETC. Published Quarterly on the first of January, April, July and October ; each Number having at least 264 large and closely printed pages. AVHEN NECESSARY, CASES ARE Fully Illustrated with LITHOGRAPHIC PLATES and WOOD-CUTS. ALSO, &()e JlteMcal Stfevus a nb Cibrarg, Of 32 Large Pages, Published Monthly, is given Gratis to Subscribers to The Journal who pay, by the first of February of each year, Five Dollars free of expense to the Publishers. Under the new law the postage on the Journal is reduced to about 13| cents per number, while the News and Library is sent through the mail as a Newspaper. Persons wishing to subscribe, to commence with the January number for 1847, should advise the publishers at once, as the whole quantity for the present and two past years was taken up early in the year. The publishers do not deem it necessary to refer to the past course of the Journal. It is suffi- cient that for the last TWENTY-SEVEN YEARS it has received the approbation of the profession at home and abroad ; but they would call attention to the extended and liberal arrangement exist- ing and to be pursued that shall embody the latest intelligence from all quarters. ITS PAGES WILL BE DEVOTED FIRST TO ORIGINAL COMMUNICATIONS FROM ALL SECTIONS OF THE UNION, WITH REVIEWS OF ALL NEW WORKS OF INTEREST, AND i D ! L D © © IR /& P U Q © A L ^©TB©Eig While its QUARTERLY SUMMARY will embrace a full and extended RETROSPECT AND ABSTRACT FROM THE VARIOUS FOREIGN AND DOMESTIC JOURNALS. With reference to this department, the arrangements of the publishers are very extensive and em- brace for the gleanings of the editor the various Journals from GREAT BRITAIN, FRANCE, GERMANY, DENMARK, ITALY, .7.V/J OTHER SECTIONS OF THE WORLD. INCLUDING AS PROMINENT AMONG THE ENGLISH, BRAITHWAITE’S RETROSPECT, RANKING’S HALF-YEARLY ABSTRACT, THE LONDON MEDICAL TIMES, THE LONDON MEDICAL GAZETTE, FORBES’ BRITISH AND FOREIGN QUARTERLY. (Continued on Page 31.) frCr This paper may be delivered to any physician if declined by the person to whom it is ad- dressed, or if they have removed — and Postmasters and others will particularly oblige the publish- ers by furnishing a list of the Physicians and Lawyers of their county or neighborhood. In addition to the business it may bring to the office, a copy of “ The Complete Florist,” or such other volume, will be sent by mail gratis for any ten or more names furnished free of cost. Philadelphia, July, 1846. • v\» »