The vasa efferentia of the inguinal glands, three or four in number, are much larger than the vasa inferentia; they receive the contents of all the lymphatics hitherto described, and pass under Poupart's ligament with the femoral ar tery and vein to become the vasa inferentia of the glands associated with the external iliac artery. From the anterior and lateral muscular paries of the abdomen, the lymphatics accom pany the epigastric and circumflexa ilii arteries, and terminate in the external iliac glands. The external iliac glands are also joined by the vasa efferentia from the glands accompanying the internal iliac artery. These latter receive the lymphatics, associated with the gluteal, ischiatic, and obturatrix arteries, which enter the pelvis by the same openings as the arteries which they accompany. The lymphatics from the prostate gland and vesicular seminales, from the bladder and rectum, from the vagina and uterus, those accompanying the internal pudic vessels derived from the interior of the penis and clitoris, and those from the walls of the pelvis, all terminate in the internal iliac glands.
The glands accompanying the common iliac artery, on the one hand, receive their efferent vessels from the internal and external iliac glands, and on the other give their efferent vessels to those, associated with the aorta,which constitute the lumbar glands.
The lymphatics of the testicle, of the kid neys, and renal capsules, those accompanying the lumbar arteries, the lymphatics of the rectum, sigmoid flexure and descending por tion of the colon, all terminate in the lumbar glands. Those from the testicle are derived from the interior as well as from the surface of the organ; they take their course upwards with the spermatic arteries and veins in several branches, to reach the renal and lumbar glands.
The lymphatics of the kidneys emerge from its substance at the fissure of the organ, having taken their course with its bloodvessels, where they are joined by the superficial vessels; they pass through the small renal glands, and ulti mately reach the lumbar glands.
The lymphatics of the renal capsules unite chiefly with those of the kidneys, but also on the left side with those of the spleen, and on the right with those of the liver. They are at length conducted to the lumbar glands. The lymphatics accompanying the lumbar arteries receive their branches from the structures sup plied by those arteries, and empty themselves into the lumbar glands. The lymphatics from the descending colon, from its sigmoid flexure, and from the rectum, take somewhat the course of the inferior mesenteric artery and its branches; they pass through their appropriate glands, and are ultimately received by the lumbar glands.
The vasa efferentia of the lumbar glands cannot be said to receive the contents of all the vessels and glands hitherto described ; they, in fact, empty themselves into the principal lymphatics by whose union the thoracic duct is formed, or into the duct itself soon after its formation. The principal lymphatics above alluded to may be traced more or less dis tinctly from Poupart's ligament to the second lumbar vertebra, where they usually unite to form the thoracic duct, the vessels of opposite sides communicating freely with each other.
Their position and arrangement will be well understood by the accompanying wood-cut.
psow muscles, to communicate freely by cross branches, and opposite to about the third lumbar vertebra to pass inwards, on the right side behind the cava, on the left behind the aorta to unite into one vessel on the body of the se cond lumbar vertebra, behind the root of the right renal artery, and thus to form the com mencement of the thoracic duct. In the subject from which the drawing was taken the branches did not unite in the abdominal cavity. Two nearly equal-sized vessels ascended into the thorax, which, however, soon coalesced. The union generally takes place opposite the abrupt dilatation marked No. 11, and which would be termed the receptaculum chyli, although the lacteals generally enter above this point.
The lacteals, properly so called, take origin from the small intestines. During the process of digestion they contain a white fluid, the chyle, but at other times their contents arc colourless like those of the rest of the lympha In the dissection from which this wood-cut was taken, the injection did not pass freely into the glands, from which circumstance the vessels are more distinctly seen, as it permitted the glands which partlyconcealed them to be removed with out causing extravasation. These vessels, after taking somewhat the course of the external, in ternal, and common iliac arteries, may be seen to ascend pretty close to the inner edges of the tie system ; they are joined by the lymphatics of the caput coli, the ascending and transverse colon; they also communicate with the lym phatics of the liver, spleen, pancreas, and stomach. The more modern opinion is, that the lacteals commence from the villi and from the spaces between the villi in the small intes tines, not by open mouths, but by a delicate net work of vessels, through the coats of which the chyle is supposed to enter by imbibition. This incipient net-work of lacteals terminates at the roots of the villi in branches, which perforate the muscular coats of the intestines, the trunks of which may be easily distinguished under the serous coat, taking a transverse course to gain the cellular interval between the layers of the mesentery. These are what may be termed the deep-seated lymphatics of the intestines which alone contain the chyle, but there are superficial lymphatics belonging to the intes tines situated immediately under the peritoneal coat, which take a longitudinal course and join the deep-seated vessels. From the intes tine the principal branches pass in nearly straight lines between the layers of the mesen tery, where they traverse the mesenteric glands to accumulate from every portion of the small intestine around the trunk of the superior mesenteric artery. The lymphatics from the mecum, the ascending and transverse colon, which have passed through their appropriate glands and have accompanied more or less the ilio-colic and colic arteries between the layers of the meso-colon, now join the lacteal vessels. The vasa efferentia from the mesenteric glands form two or more trunks, which, conducted by the root of the superior mesenteric artery, reach the thoracic duct, into which they empty their contents just above its commencement.