Veins. 



247 



597. The Venous Plexus of the 



Spermatic Cord, Plexus pampini- 



formis. 



The inferior Vena cava is formed by 

 the junction of the right and left common 

 iliac veins. It perforates the central tendon 

 of the diaphragm, enters the pericardium, and ter- 

 minates in the lower and back part of the right 

 auricle of the heart. Each common iliac 

 vein is formed by the union of the external 

 (V. cruralis) and internal (V. hypogastrica) 

 iliac veins. The left common iliac 

 vein is longer than the right, and receives 

 the two Venae sacrales mediae. 



The V. cava inferior receives : 



a) The lumbar veins, which freely 

 anastomose with each other and form the Plexus 

 venosus lumbalis ; 



b) The internal spermatic veins 

 arise from the pampiniform plexus of the sper- 

 matic cord, and ascend, the one on the right 

 side directly to the V. cava inferior, the one 

 on the left side to the renal vein ; 



c) The renal veins, the left longer 

 than the right; 



d) The suprarenal veins, the left 

 of which usually opens into the left renal vein ; 



e) The hepatic veins, two or three 

 larger and several smaller ; 



f) The phrenic veins. 



In the foetus the umbilical vein also 

 opens into the inferior Vena cava, whereby this 

 vein receives arterial blood (see Fig. 607). 



Cap. 

 epidi 



