134 ELEMENTS OF MAMMALIAN ANATOMY. 



The abdominal aorta gives off the following branches: 

 the coeliac axis, the superior mesenteric, the adrenolumbalis, 

 a pair of renal, a pair of genital, an inferior mesenteric, a 

 pair of iliolumbar, seven or eight pairs of lumbar, a pair 

 of external iliacs, a pair of internal iliacs, and a caudal 

 artery (Fig. 72). 



The coeliac axis is a large branch arising just caudad to 

 the diaphragm and gives off the hepatic branch to the liver, 

 pancreas, and duodenum, the gastric to the stomach, and 

 is continued as the splenic, supplying the pancreas and the 

 spleen. The phrenic artery, supplying the diaphragm, 

 sometimes arises from the coeliac axis, but usually from the 

 adrenolumbalis. 



The superior mesenteric is about the same size as the 

 coeliac axis, and arises within one centimeter caudad. It 

 sends branches to the pancreas and both intestines. The 

 adrenolumbalis is a small branch on the left side dividing 

 into the adrenal, phrenic, and muscular. The renal arteries 

 supply the kidneys and usually the suprarenal bodies. The 

 genital arteries are small, and arise from one to two centi- 

 meters caudad of the renal arteries. They pass obliquely 

 caudad to the ovaries in the female, and the testes in the 

 male. The inferior mesenteric is almost as large as the 

 superior mesenteric. It is distributed to the large intestine. 

 The pair of iliolumbar arteries are small branches supply- 

 ing the muscles of the iliac region. 



Four or five pairs of lumbar arteries are given off from 

 the dorsal side of the aorta at regular intervals between 

 the diaphragm and the origin of the external iliac arteries. 

 They supply the muscles of the back and spinal cord. The 

 external iliac arteries are the largest branches of the ab- 

 dominal aorta and carry blood to the hind-limbs. The 

 internal iliac arteries arise more than a centimeter caudad 

 to the external iliacs and furnish blood to the pelvic viscera 



