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 Part III. 234 A N A T O M Y. ward the circumference or cuter furface of the kidneys. The inferior defeending aorta ends at the laft verteOrdinarily, the right renal artery paffes behind the bra of the loins, and fometimes higher, in two large la-, vena Cava .and renal vein on the other fide ; and the left teral branches, one on the right hand, the other on the left, called arteria iliaca ; each of which is a common artery, firft behind and then before the vein. to two other arteries of the fame name. This hi-, The arteries of the renal glands, which may be term- trunk ed capfulares, arife fometimes from the aorta furcation lies on the anterior and left fide of that of the above the arteria renalis, and give out the arteriae adipo- vena cava. fas, which go to the fat of the kidneys. Sometimes' The primitive iliac arteries divaricate gradually as they they come from the trunk of the cssliaca. The right defeend, advancing obliquely toward the anterior and lowcapfular artery comes molt commonly from the arteria re- er part of the olfa ilium, without any confiderable raminalis of the fame fide, near its origin j the left from the fication for about the breadth of three fingers, except a few very fmall arteries that go to the os facrum. They aorta, above the renalis. The fpermatic arteries are commonly two in number, likewife give fmall arteries to the peritonxum, to the coats fometimes more. They are very fmall, and go out an- of the veins, and to the fat and ureters. teriorly from the aorta defeendens inferior, near each o- The right iliac trunk paffes firff on the forefide of t-her, about a finger’s breadth below the arteriae renales, the origin of the left iliac vein, and runs down on the between the two mefentericx, or between the renales forefide of the right vein, almofl: to the place where it goes out of the abdomen, its courfe being there diredted and mefentericx inferiores. They fend off to the common membrane of the kidney more inwardly. The left trunk goes down likewife befmall branches, named arteria adipofa -, and afterwards fore the left vein, but lies a little toward the infide as it they run down upon the pfoas mufclcs, on the fore-fide leaves the abdomen. of the ureters, between the two laminse of the perito- About three fingers breadth from their origin, each iliac trunk is divided into two fecondary arteries, one exKxum. They give feveral confiderable branches to the perito- ternal, the other internal. The external artery has no neum, and communicate both with the mefentericx and particular name; the internal is termed hypogajlrica. adipofx. They likewife fend fmall arteries to the ureters. The external iliaca on each fide runs down on the iliAfterwards, they pafs in men through the tendinous ac mufcle to the ligamentum Fallopii, under which it Openings of the abdominal mufcles in the vagina of the goes out of the abdomen. In this courfe, it gives off peritoneum, and are diftributed to the tellicles and epi- only a few finall arteries to the peritonxum, and other didymis, where they communicate with a branch of the parts near it; but as it paffes out of tfie abdomen under iliaca externa. the ligament, it detaches two confiderable branches, one In women they do not go out of the abdomen, but internal, the other external. are difixibuted to the ovaria and uterus, and communi- The internal branch is named arieria epigajlrica, and cate with branches of the hypogallrica, at the jagged ex- goes out anteriorly from the external iliaca. From thence tremities of the tubx Fallopianx. it runs obliquely upward on the tendon of the tranfverfe The lumbar arteries go out pofteriorly from the infe- mufcle towards the poflerior part of the reftus. rior defeending aorta, in five or fix pairs, or more, much Afterwards the epigaftric artery runs up along the pofterior or inner fide of this mufcle, fending ramifications in the fame manner with the intercofials. They may be divided into fuperior and inferior. The to the tendons of the neighbouring mufcles, be. and fuperior fend final) branches to the neighbouring parts of then lofes itfelf by a true anaftomofis of feveral ramifithe diaphragm and intercoftal tnufeles, and fupply the cations, with the mammaria interna. place of feini-intercoftal arteries. The external branch of the outer iliaca goes off lateThey are diftributed on each fide to the pfoas mufcles, rally from the outfide of that artery under the ligamento the quadrati lumborum, and to the oblique and tranf- tum Fallopii, and from thence to the internal labium of verfe mufcles of the abdomen; and by perforating the the os ilium, where it divides into two, and is ramified oblique mufcles, they become external hypogaftric arte- on tha oblique and tranfverfe mufcles of the abdomen ries. They go likewife to the vertebral mufcles, and to communicating with the arteria lumbaris. the bodies of the vertebrx, and enter the fpinal canal Befides thefe two branches, the external iliaca gives through the lateral notches, to go to the membranes, off a fmall ramus internally, under the ligament, which tire, forming rings much in the fame manner with the runs to the vagina of the fpermatic rope ; and fometimes iptercoftals. another fmall twig goes from the outfide to the os ilium. The arterix facrx go out commonly from the back The internal iliaca or hypogaflrica, having run a little part of the inferior defeending aorta, at the bifurcation. more than a finger’s breadth inward and backward, bends They are two, three, or four in number, and fometimes by fmall degrees obliquely forward, and toward the out, but one. They are ramified on the os facrum, and on fide ; and afterwards contrafling in its dimenfions, it end$ the neighbouring parts of the peritonxum, inteftinum in the umbilical artery, which ought to be looked upon recShim, fat, be. and enter the canal of that bone through as a true continuation of the trunk of the hypogaftrica*. the arcerior holes, being there dillributed towaid each fide. This arteria umbilicalis afeends on the fide of the They likewife fend fmall arteries to the large fafciculi of bladder, and having detached fmall rami ;to that vifeus nerves, which go out through the holes of the os facrum^ and to the neighbouring parts of the peritonxum, be. and they penetrate ths inner fubdance of that bone. it contrafls, and in adults is quite clofed up above the middle