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2^3 Part VI. A N A T 6 M V. curvature of that canaf, and carry it as in a fcarf or fling. cover an infinite number of fmall veflels of another This is what forms the external or membranous coat of kind running from gland to gland. Thefe veflels are extremely thin and tranfparent, and the inteflines. on the infide with numerous valves, which apThe mefocolon is the continuation of the mefentery, furnifhed on the outfide like little Imall knots very near each which having reached the extremity of the ilium, con- pear They go out from each gland by ramificationsr tradls and changes its name. At this place the particu- asother. fo many roots, and having formed a fmall trunk, lar lamina which is turned to the right fide, forms a theyby are again divided, and enter fome neighbouring fmall tranlverfe fold, called ligamentum coii dextrum. gland by the fame kind of ramifications by which they Afterwards the mefocolon afcends towards the right kidney, where it feems to be loft by the immediate ad- went out from the former. hcfion of the colon to that kidneyj and to the firft incur- They are termed lymphatic vefiels, becaufe for the vation of the duodenum. Then it appears again, and, in- moft part they contain a very clear, limpid, though mucreafing in breadth, it continues its courle aim oft tranf- cilaginous ferum, called lympha by anatomifts. But as verfely under the liver, ftomach, and fpleen, where it be- they have likewile been obferved to be filled with a white gins to turn downward, under the left hypochondriunj, milky fluid, called chyle, they have been called vafa chyIfera,, or verne ladle*. They have-the name of veins, toward the kidney on the fame lide. Through this whole courfe, the mefocolon extends in becaufe their valves are difpofed as thofe of the ordinary breadth, and forms nearly a tranfverfe femicircular plane, blood-veins, and becaufe the fluid which they contain very little plaited at its great circumference. By this runs from fmaller into larger tubes. circumference or edge, it is connected to the colon ; and They derive their firft origin from the tunica villofa of hides that ligamentary band of this inteftine, which runs the inteftines, and chiefly from that of the fmall inteftines, along its fmall curvature. By its Ihort or fmall edge, it by a. great number of fmall capillary roots. From thefe forms the triangular cafe of the duodenum ; and by its roots there arifes, between the coats of the inteftines, a great edge, the external coat of the colon, in the fame kind of rete mirabile, which furrounds. almoft the whole manner as the mefentery does that of the fmall inteftines. circumference of the inteftinal canal, between the mufeuAs it paftes under the large extremity of the ftomach, it lar and external coat. adheres a little to the lower portion of that extremity, as This reticular texture of lafleal velfels keeps clofe to the diaphragm does to the upper. the external coat, and leaves the canal along with it, on Having got below the left kidney, it contrails and the fide of the mefentery, where it forms two planes of Forms another tranfverfe fold, called ligamentum celiji- ramifications, plainly diitinguilhed from each other by nijlrum. Afterwards it expands again, but not fo much the cellular fubftance, and adhering clofely to the infide as in the upper part, and runs down on the left pfoas of the two membranes of the mefen.tery. In this fepainufcle, toward the laft vertebras of the" loins. This rate ftate they run on the laminae of the mefentery, as defcending portion is fixed to the convolutions of the co- far as the firft mefenteric glands, where they unite again lon in the fame manner as the fupersof portion is to the into one plane. arch of that inteftine. After this union, the ladeal vefiels are diftributed alThe inteftinum redtum is likewife inverted by a parti- moft uniformly through the whole extent of the mefencular production of the peritonaeum, called commonly by tery, from its circumference to its origin or adhefion to the barbarous name of meforeftum. This production is the vertebras cf the back, between the mefenteric glands, very narrow ; and, about the middle of the forefide of the which they join, and form frequent anaftomofes or comreCtum, it forms a tranfverfe femicircular fold, which munications. appears when the inteftine is empty, but is loft when it Having pafled through the mefentery, the ramifications is filled. begin to unite as they approach the fpina dorfi, and confequently their number is leflened, and their fize increa; and having pafled the laft mefenteric glands, they glandula: mesenterica:, vasa fed terminate about the middle of the adhefion cf the mefoLYMPHATICA & LACTEA. colon in fmall common trunks, which receive a great Between (he laminae of the mefentery, a great numof lymphatic vefi'els from the glanduke lumbares, ber of glands lie fcattcred through the cellular fjbftance. number and others below thefe. In the natural ftate, thefe glands are fomethingof the fi- The ladfeal veflels which he between the meftnteric gure of lentils or little round beans ; fonie of them being glands and middle of the mefocolon to the fpina orbicular, others oval, but all of them a little flatted. dorfi, run down onadhefion the body of the inferior aorta, beThefe glands are of the number Of thofe that anato- tween the extremities of ike final! mufeie of the diamifts call glandule conglobate, the ftruCture of which and terminate m a kind of erftern, called by fome. is not as yet fufficiently known. They feem to be of a phragm, chyli, by others receptaculum Pecquetts. cellular fubftance, furroundcd by a very fine membrane receptaculum part of the receptaculum chyli lies beor coat, on which, by the help of microfcopes, we difco- hindThethegreateft right portion cf the inferior mufcle of the diaver an intertexture Of particular filaments. phragm, cn the of the aorta, at the union of Befides the blood-velfels which are diftributed in a laft vertebra ofrightthe fide back with the firft of the loins. reticular manner in the mefenteric glands, and bdides the It is a kind of membranous veficle, the conformation of many nervous filaments fpread through them, we dif- which is various in human fubjetts, Sometimes it is of
