VASCULAR SYSTEM 53 



B. — Post-cava. 



The Post-cava or Inferior Vena Cava is the large 

 vein which returns blood from the posterior part 

 of the body, and empties into the right auricle. It 

 receives its first branch as it pierces the diaphragm. 



1. The Phrenic Veins collect blood from the dia- 

 phragm, and enter the post-cava just as it pierces 

 that organ. 



2. The Hepatic Veins collect the blood from the 

 liver, and empty into the post - cava, near the 

 phrenic veins. 



3. The Suprarenal Veins collect the blood from 

 the abdofninal walls and adrenal bodies, and usu- 

 ally empty into the post-cava, near the level of the 

 corresponding arteries. 



4. The Renal Veins correspond to the arteries of 

 the same name. 



5. The Spermatic and Ovarian Veins correspond to 

 the spermatic and ovarian arteries, though usually 

 those of the left side empty into the renal vein in- 

 stead of the post-cava. 



6. The Ilio-lumbar Veins also correspond to the 

 ilio-lumbar arteries. 



7. The Common Iliac Veins are two large veins 

 which unite with the caudal vein to form the post- 

 cava. They are formed by the union of the in- 

 ternal and external iliac veins, which have a 

 similar distribution to the arteries of the same 

 name. 



