THE ABDOMEN, INTERIOR. 521 



to leave the abdominal cavity through the caval opening in 

 the diaphragm. It lies at the right side of the aorta, in 

 contact with it below, but separated from it above by the 

 right crus of the diaphragm and Spigelian lobe of the liver. 



The vena cava is crossed by the right spermatic artery, 

 transverse colon, mesentery, duodenum, pancreas, portal 

 vein, and liver, and lies in a deep groove in the substance 

 of the liver (the caval fissure). 



Tributaries. (i) The common iliac veins. 



(2) The lumbar, four on each side, the left being a little 

 longer than the right. 



The lumbar veins are joined together by a vertical vein 

 which runs upward in front of the transverse processes of 

 the vertebrae to communicate above with the azygos major 

 (on the right side), and azygos minor (on the left side). 

 See page 348. 



(3) The spermatic veins (ovarian in the female). Return 

 the blood from the testicle ; on the cord they form a plexus 

 of dilated and convoluted veins called the pampiniform 

 plexus. In the female this plexus is formed about the 

 ovary. The left spermatic (or ovarian) vein empties into 

 the left renal vein. 



(4) The renal veins. Return the blood from the kidneys. 

 The left is a little longer than the right, and receives 



the left spermatic (or ovarian) vein. The renal artery lies 

 behind the vein. 



(5) The suprarenal veins. These return the blood from 

 the bodies of the same name. The left suprarenal usually 

 empties into the left renal, the right into the vena cava. 



(6) The hepatic veins. Two or three large veins. Re- 

 turn all the blood from the liver and empty into the vena 

 cava as it lies in the caval fissure of the liver. 



(7) The inferior phrenic veins. Collect the blood from 



