MAMMALIAN ANATOMY 
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External iliac, giving off branches to external pelvic 
region and continuing as the femoral artery into 
the leg. 
Internal iliacs, passing into the pelvic cavity where 
branches are given off to the bladder and other 
pelvic organs, and to the pelvic walls and the 
gluteal region (to trace these into the pelvic cavity 
the pubic bones must be separated by cutting 
through the symphysis). 
Caudal (median continuation of the aorta). 
( b ) Veins (injected blue). 
i. Anterior branches, entering anterior vena cava: 
Brachiocephalics, right and left (in case there are two 
anterior venae cavae, e.g ., rabbit, there are no 
brachiocephalics): 
Subclavian. 
External jugular. 
Internal jugular. 
ii. Thoracic branches: 
Right azygos, receiving intercostal branches, and 
entering the anterior vena cava. 
iii. Abdominal branches, entering posterior vena cava: 
Phrenics. 
Hepatics. 
Renals. 
Spermatics or ovarian (note lack of symmetry in 
right and left sides). 
Iliolumbars. 
Common iliacs, with divisions and branches corre¬ 
sponding to those of the iliac arteries. 
2. Portal System (injected yellow). 
This consists of branches from the digestive tract, pancreas, 
and spleen which unite to form the hepatic portal vein. 
This enters the liver and divides, distributing the blood to its 
capillaries. 
