THE VASCULAR SYSTEM 393 



the jejunum and ileum as well as the mesentery. The colic arteries carry 

 blood to the colon. 



The renal arteries supply kidneys, adrenals, and the upper portion 

 of the ureters. Thus the adrenals receive blood from three sources, 

 phrenic, renal, and middle adrenal arteries. The internal spermatic 

 arteries are given off just below the renals and pass along the spermatic 

 cord to the testes. From them branches are given off to the ureters, 

 cremaster muscle, and epididymis. The ovarian arteries in the female 

 correspond to the spermatic arteries of the male. Branches from the 

 ovarian arteries pass to the ureters, ovaries, uterine tubes, uterus, and 

 to the round ligaments of the uterus. 



The inferior mesenteric artery leaves the abdominal aorta about an 

 inch and a half above its division into the iliacs. It is distributed chiefly 

 to the colon and rectum. Arising just above the bifurcation of the 

 abdominal aorta, a median sacral artery supplies the last lumbar vertebra, 

 sacrum, and coccyx. 



The common iliac arteries are formed by the bifurcation of the abdom- 

 inal aorta when it reaches the level of the fourth lumbar vertebra. At 

 the level of the lumbo-sacral articulation, the right and left common 

 iliacs divide into internal or hypogastric and external iliac arteries. 

 From the internal iliac arteries both visceral and parietal branches are 

 given off. The visceral branches are the umbilical, inferior vesical, 

 middle hemorrhoidal, uterine, and internal pudendal arteries. The 

 parietal branches are the ilio-lumbar, lateral sacral, obturator, and gluteal 

 arteries. The ilio-lumbar arteries are serially homologous with the 

 lumbar arteries and have a similar distribution to the vertebrae and 

 lumbar muscles. 



The lateral sacral arteries, as their name suggests, supply chiefly 

 the sacrum. The obturator artery supplies the bladder, iliac and pubic 

 bones, and obturator and adjacent muscles. The gluteal arteries supply 

 gluteal and neighboring muscles. 



Of the visceral branches of the hypogastric artery the umbilical 

 artery supplies chiefly the bladder. The inferior vesical artery sends 

 branches to the bladder and prostate gland. The middle hemorrhoidal 

 artery carries blood to the rectum and, in the female, to the vagina. 

 The uterine artery after a tortuous course supplies the uterus and vagina. 

 The internal pudendal artery is distributed to the muscles of the perineum, 

 penis or clitoris, and to the scrotum or labia majora. 



The external iliac artery is the larger of the two vessels into which 

 the common iliac artery divides. In its course it gives off inferior epi- 

 gastric, deep circumflex, iliac, as well as smaller branches to adjacent 

 muscles. As the external iliac passes into the thigh it becomes the 

 femoral artery. Continuing to the knee it becomes the popliteal artery. 



