(b) 
(c) 
(d) 
THE ABDOMINAL AORTA. 203 
aorticus and passing to the diaphragm (usually seen better 
on the right side). 
The suprarenolumbar artery (a. suprarenolumbalis), 
arising on either side from the renal artery, and passing antero- 
laterad to the body-wall, supplying also the suprarenal body. 
The lumbar arteries (aa. lumbales), seven pairs of vessels 
distributed metamerically to the lumbar portion of the 
body-wall. Six pairs arise from the dorsal wall of the aorta, 
the seventh from the median sacral artery. They arise as 
single trunks, branching into right and left. 
The median sacral artery (a. sacralis media) arises from the 
dorsal wall of the aorta near its posterior end, and passes 
backward on the ventral surface of the sacrum in the middle 
line. Its first portion is concealed from the ventral surface 
by the common hypogastric vein. 
2. The common iliac artery (a. iliaca communis) is a short 
trunk, the branches of which pass to the posterior limb, the wall of 
the pelvis, and the pelvic viscera. After giving off the iliolumbar 
artery (a. iliolumbalis), which passes laterad to the body-wall, the 
common iliac divides into two branches the connections of which 
may be traced as follows: 
(a) 
(b) 
The external iliac artery (a. iliaca externa) is the larger 
lateral branch, directed toward the inguinal ligament, over 
which it passes to the medial surface of the limb, becoming the 
femoral artery. Near its crossing with the ligament it gives 
off the inferior epigastric artery (a. epigastrica inferior), 
the main portion of which passes forward in the medial 
portion of the abdominal wall. 
The hypogastric artery (a. hypogastrica) is the smaller 
medial branch, directed backward on the dorsal wall of che 
pelvis. Its course may be traced without injury to the 
nerves of the lumbosacral plexus. At its junction with the 
external iliac the vessel gives off the umbilical artery 
(a. umbilicalis) to the bladder, or in the female first to the 
vagina and uterus (a. uterina). The obturator artery 
(a. obturatoria) passes laterad to the pelvic wall and the 
middle haemorrhoidal to the side of the rectum and 
