154 HANDBOOK OF ANATOMY 



Tributary. External jugular formed on the surface of the 

 sterno-mastoid by the union of the terminal branch of the 

 temporo-maxillary with the posterior auricular vein, which drain 

 the outer side of the head and neck. 



The Inferior Vena Cava is formed opposite the right side 

 of the body of the fifth lumbar vertebra behind and external 

 to the right common iliac artery by the union of the common 

 iliac veins. It passes up the posterior wall of the abdomen 

 to the right of the aorta and on the right crus of the dia- 

 phragm, and passes through the latter at the level of the eighth 

 dorsal vertebra. It then pierces the pericardium and enters 

 the lower and back part of the right auricle. The vessel lies 

 below on the bodies of the lumbar vertebrae, the right psoas, 

 and the right crus of the diaphragm, the right renal artery, 

 and suprarenal capsule. Anterior to it are the right common 

 iliac artery, the third part of the duodenum, head of the pan- 

 creas, the portal vein, the first part of the duodenum, and the 

 posterior surface of the liver. On its left side are the aorta and 

 the left crus of the diaphragm. 



Tributaries. Hepatic. 



Inferior phrenic. 



Suprarenal. 



Renal. 



Lumbar. 



Spermatic or ovarian. 



The Hepatic veins are two in number, which .open into the 

 inferior vena cava just below the diaphragm, and bring the 

 blood from the liver which has entered it through the hepatic 

 artery and portal vein. 



The Inferior Phrenic veins are formed by the venae comites of 

 the arteries supplying the diaphragm. 



The Suprarenal veins are one each from the suprarenal 

 capsules. Sometimes the one on the left side enters the left 

 renal vein. 



The Renal veins each issue from the hilum of the kidney, the 

 left one being longer than the right. The left one crosses in 

 front of the left psoas, the left crus of the diaphragm, and 

 the aorta just below the superior mesenteric artery, and lies 



