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ANATOMY AND PHYSIOLOGY OP 



into the right and left hepatic ; the right, — 

 the larger and shorter one, — after giving off 

 a considerable branch to the portio media, 

 turns back to reach the right lobe ; the left, 

 after giving off a branch or two to the mid- 

 dle portion, penetrates the left lobe. 



The anterior, or great mesenteric, is the 

 next vessel to the coeliac, and arises from 

 the under part of the posterior aorta. From 

 its origin, it passes downward Avithin the 

 layers of the mesentery, detaching some 

 small twigs to the pancreas ; it then sepa- 

 rates into larger vessels (commonly from 

 eight to twelve in number), from which are 

 derived a branch that runs to the duode- 

 num ; several other branches encircle and 

 ramify on and around the intestines. 



The renal or emulgent artsries leave the 

 aorta at right angles just below the preced- 

 ing vessel ; they each pass into the respect- 

 ive kidneys, and therein divide into branches 

 that penetrate the glandular substance. 



The spermatic arteries, right and left, 

 originate from the under part of the aorta ; 

 they pass out of the abdomen, at the ab- 

 dominal ring, to the testicles. In the female, 

 they pass to the ovaries, fallopian tubes, 

 and horns of the uterus. 



The posterior aorta also gives off the 

 small mesenteric, and five or six pairs of 

 lumbar arteries. Under the last lumbar 

 vertebrae, the aorta gives off two pairs of 

 arterial trunks, called the external and inter- 

 nal iliacs. 



The internal iliacs give off a branch 

 called the artery of the bulb, and afterwards 

 branches into three divisions — the obtura- 

 tor, gluteal, and lateral sacral arteries. 



The artery of the bulb passes to the bulb 

 of the penis, where it terminates. In the 

 female, this artery sends its terminating 



branches to the vagina. 



It gives off the 



foetal umbilical artery. In leaving the pel- 

 vis, the prostatic artery, which detaches 

 twigs to the vesiculsB seminales, also distri- 

 butes its ultimate ramifications to the pros- 

 tate gland. It also gives off divers branches, 

 anal and perineal, to the posterior portion 

 of the rectum, anus, and parts comprising 

 the perineum. 



The obturator artery is the lowest of the 

 divisions^ of the internal iliac. Its branches 

 are tlie arteria innominati, and ramifications 

 to the obturator muscles and ligaments. Its 

 divisions are the ischiatic, which distributes 

 its branches to the triceps ; next, the pubic : 

 the internal pubic artery gives two sets of 

 branches, which pass to the penis. 



The gluteal artery is destined principally 

 to supply the gluteal muscles. 



The lateral sacral artery, having reached 

 the coccyx, divides into two branches. It 

 furnishes the sacro-spinal branches, five 

 or six in number, and the perineal artery. 

 It soon divides into several ramifications, 

 of which many run into the gluteal mus- 

 cles ; others descend on the back of the 

 thigh, and others are distributed to the anal 

 muscles, and to the skin and cellular sub- 

 stance of the perineum. The lateral sacral 

 also furnishes the lateral coccygeal, and 

 the inferior coccygeal. 



The external iliac artery, right and left, 

 results from a branch of the posterior aorta, 

 which takes place under the body of the 

 last of the lumbar vertebrae, and passes 

 into muscles, forming the inside of the 

 thighs. The vessel gives off the circumflex 

 artery of the ileum, the artery of the cord, 

 and the arteria profunda : the latter, having 

 reached the posterior quarters, it sends its 

 ramifications into the biceps. Before this 

 vessel dips into the substance of the thigh, 

 it gives rise to a large branch called the 

 epigastic artery. 



The eptg-astric artery, in passing the mar- 

 gin of the internal ring, forms a branch 

 which divides into several small arteries ; of 

 these a twig runs to the groin, and ramifies 

 among the adipose membrane and absorbent 

 glands ; then, next, a slender branch to the 

 cremaster, and subcutaneous twig to the 

 thigh, and, lastly, the external pudic artery. 



The femoral artery. — Regarding the pro- 

 funda femoris as a limb of the external 

 iliac, we descend to the femoral artery, the 

 subsequent continuation of the same trunk. 

 This artery proceeds in an oblique direction 

 down the haunch, preserving nearly the line 

 of its middle ; opposite to the head of the 



