THE VASCULAR SYSTEM 



155 



arm and hand. Second, the left 

 subclavian, which supplies the 

 left arm, brain, and sternum. 



There may be considerable 

 variation in the order and arrange- 

 ment of these branches as may be 

 seen by consulting Figs. 78 and 84. 

 The innominate artery has some- 

 times been called the brachio- 

 cephalic. Ten pairs of intercostal 

 arteries supply the intercostal 

 spaces, muscles of the back, and 

 the spinal cord. Two bronchial 

 arteries go to the lung tissue. 

 Two to four esophageal arteries 

 are distributed to the esophagus. 

 Two or three pairs of lumbar 

 arteries pierce the muscles of the 

 back. 



The abdominal aorta gives off 

 the following branches : the celiac 

 axis, the superior mesenteric, the 

 adrenolumbalis, a pair of renal, a 

 pair of genital, an inferior mesen- 

 teric, a pair of iliolumbar, seven 

 or eight pairs of lumbar, a pair 

 of external iliacs, a pair of internal 

 iliacs, (hypogastric), and a caudal 

 artery (Fig. 78). 



The celiac axis is a large branch 

 arising just caudad to the dia- 

 phragm and gives off the hepatic 

 branch to the liver, pancreas, 

 and duodenum, the gastric (gas- 

 trica sinistra) to the stomach, and 



Fig. 78. — Chief Arteries of the 

 Trunk, Ventral Aspect. 

 ar, Arch of the aorta; be, innomi- 

 nate; ce, celiac axis; cd, caudal; e, gas- 

 tric; /, gastric; gr, gastric; gas, gas- 

 troduodenalis; hp, hepatic; ht, 

 location of heart; icn, intercostals; 

 ic, external iliac; it, internal iliac; 

 il, iliolumbar; im, inferior mesenteric, 

 Is, left subclavian; //)/, left pulmonary; 

 m, splenic; o, splenic; r, right pul- 

 monary; re, renal; sp, splenic trunk; 

 Sfns, superior mesenteric; sm, sper- 

 matic or ovarian; s, adrenolumbalis; 

 1 1 2, 3, 4, 5, and 6, lumbar arteries. 



