THE FROG 4 1 



(a) The renal portal system. The renal portal vein 



enters the kidney from behind, coursing along its entire 

 lateral edge. It receives the following branches : 



The dorso-lumbar vein from the dorsal wall of the ab- 

 domen (in the female also from the oviduct) enters the renal 

 portal vein near the middle of the kidney. 



The iliac vein. This is the dorsal branch of the great 

 femoral vein of the thigh and leg. The latter runs forward 

 near the dorsal surface of the thigh past the hip-joint, then 

 turns toward the ventral surface, dividing into two branches : 

 the pelvic vein which unites with its fellow of the opposite 

 side to form the anterior abdominal vein, and the iliac 

 vein which passes dorsally and anteriorly to unite with 



The sciatic vein. This, like the iliac vein, conveys blood 

 from the thigh to the renal portal vein. 



(&) The hepatic portal system. The liver receives 

 venous blood from two sources : first, from the posterior 

 limbs and bladder by means of the anterior abdominal vein; 

 second, from the digestive system by means of the hepatic 

 portal vein. 



The anterior abdominal is formed by the union of the 

 pelvic veins ; immediately beyond this point it receives the 

 vesical vein from the bladder. It passes thence forward 

 along the mid-ventral body wall, receiving branches from 

 the body wall, and opposite the liver it ascends to enter the 

 substance of the liver. Just before reaching the liver it di- 

 vides into three branches, two passing directly to the liver 

 and a third communicating with the hepatic portal vein. As 

 the anterior abdominal vein turns up toward the liver it re- 

 ceives a small branch, the cardiac vein, from the base of the 

 truncus arteriosus. 



