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 2 69 ANATOM Y. Part VL are in pan' lodged in the veficula fellis, and in part run The proper membrane having furrounded the kidney dire&ly into the duodenum. all the way to the firms, joins the veftels at that place, and The fpdeen, omentum, appendices epiploicse, adipofe accompanies all their ramifications through the body of ftrata of the mefentery, and thofe of the great inteftines, the kidney, in form of a vagina or capfula. and even the pancreas, with the whole feries of glands We may diftinguift three kinds of fubftances iri the kidin the inteftinal canal, feem to contribute to the forma- ney; an exterior fubftance, which is thick, granulated, tion of the bile, as fo many auxiliary or rather prepara- and in a manner cortical; a middle fubftance, which is medullary and radiated, called Jiriata, fulcata, or tubutof'y'organs. ' The vehicular bile appears to be more exalted than that laris, becaufe it feems to be made up of radiated tubes ; in the hepatic du£t ;• and by meeting in the duitus cho- and an inner fubftance, which is only a continuation of lidochus, they feem to compofe a third kind of bile, the fecond, and terminates on the infide by papilla, for which without the cyftic or vehicular bile would perhaps which reafon it is called papillaris. be too mild, and too acrid without the hepatic. This The papill®, which are only a continuation of the mebile mixes in the duodenum with the pancreatic juice, dullary fubftance, are often a little paler than that fuband with that of the inteftinal glands; and from this ftance. They are ten or twelve in number, very dimixture a fluid refults, which is proper to feparate the ftind from each other, refembling the fame number of chylous matter from the grofs and uhelehs part of the a- cones, with very broad bafes and obtufe apices. limentary pulp, as it comes from the ftomach. At the point of each papilla we fee, even without a microfcope, in a fmall depreffion, feveral very fmall holes, through which little drops may be perceived to RENES & URETERES. run when the papill® are comprelfed. Thefe are little The kidneys are two pretty folid, glandular bodies, drops of urine, which being filtrated, partly in the cortifltuated in the pofterior part of the cavity of the abdo- cal, partly in the medullary or tubular fubftance, do afmen, on each fide of the lumbar vertebrae, between the terwards pafs through the fubftance of the papill®, and iaft falhe ribs and ofl'a ileum. The right kidney lies un- are difcharged by thefe orifices. der the great lobe of the liver, and is confequently low- Each papilla lies in a kind of membranous calix or er than the deft, which lies under the fpleen. infundibulum, which opens into a common cavity called The figure of the kidneys refembles that of a large the pelvis. This pelvis is membranous, being of the bean, their circumference being convex on one fide, and fame ftrudhire with the calices, of which it is a continuaconcave on the other. The concave fide is turned to tion ; and its cavity in man is not uniform, but diftinthe vertebras, and the convex fide the oppofite way. guifted into three portions, each of which contains a In each kidney we obferve a fore and back fide, an certain number of infundibula or calices, together with upper and lower extremity, a great and fmall curvature, the papill® which lie therein. and a convexity and concavity. At the place where thefe infundibula furround the The back-fide is broader than the fore-fide ; and the bafes of the papill®, they fend pi oduftions into the meupper extremity is a little broader and more incurvated dullary or radiated fubftance of the kidney, which acthan the lower. The depreffion in the fmall curvature is company the blood-veflels, and ferve for capful® or vaoblong and uneven, refembfing a finus, furrounded by fe- gin® to all the vafcular' arches, both arterial and venal, veral tubercles; and as it is turned a little toward the and to their different ramifications, quite through the fore-fide, this fide is fomething narrower than the other. cortical fubftance, and as far as the furface of the kidney. The kidneys are furrounded by a very loofe membra- After the infundibula have contracted in a conical form nous and cellular covering, called membrana udipofa, round the apices of the papill®, each of them forms a becaufe in fat perfons the cells of this fubftance are filled fmall ftort tube or gullet, which, uniting at different difwith fat. tances along the bottom of the finus of the kidney, form The proper coat or membrane of the kidneys is com- three large tubes, which go out from the finus in an o pofed of two laminae, between which there is likewife a blique direction from above downwards, and immediatevery fine cellular fubftance, which may be made fenfible ly afterwards unite into one trunk. by blowing through a pipe between the two laminae. This trunk becomes a very long canal, called the ureThe external lamina is very thin, and adheres clofely ter. In men the three tubes fupply the place of what is to the internal lamina, by means of the cellular fub- called the pelvis in brutes, and might properly be callftance. The internal lamina penetrates every where, by ed the roots or branches of the ureters than the pelvis. numerous elongations, into the fubftance of the kidney, The ureters are commonly two in number, one for each from which it cannot be feparated withsut tearing. kidney. The furface of the external lamina is very fmooth, The fimatron of the trunk, and of the roots and polifted and gliftening, and it renders the whole furface branches of each ureter, with refpeCt to the renal artery of the kidney very even and uniform. and vein, is in the following manner: The artery is in The blood-veflels having entered the kidneys, are ra- the upper part of the finus, and partly before the vein. mified every way ; andthefe ramifications fend out other The vein is about the middle, and between the artery capillary rami, which go all the way to the furface, and ureter. The ureter is in the lower part, a little bewhere they appear like irregular ftars, and furnift the hind the vein, and k is partly furrounded by one branch proper membrane of the kidneys. of the artery. From