1 84 PHYLUM CHORD ATA 



branch of the abdominal vein just mentioned. The hepatic portal 

 receives numerous intestinal veins, which lie in the mesentery and 

 come to it from the small and large intestines. It also receives the 

 splenic vein from the spleen, the two large gastric veins from the 

 stomach, a gastroduodenal vein from the stomach and duodenum, 

 and a number of small pancreatic veins from the pancreas. The 

 anterior portion of its course is through the pancreas. 



The Renal Portal System. This system is made up of veins from 

 the hind legs, the dorsal body wall, the kidneys, and, in the fe- 

 male, the oviducts ; it is joined with the abdominal vein by the 

 pelvic veins, which have just been observed, and with the kidneys 

 by the renal portal veins. 



Two veins, the femoral and the sciatic, collect the blood of the 

 hind leg on each side of the body. The femoral is the larger of 

 these. It is a large vein which appears on the ventral surface of 

 the leg, where it receives the large pelvic vein. 



The sciatic vein lies on the back of the thigh. It passes for- 

 ward and joins the femoral, and the vein so formed is the renal 

 portal, which runs forward to the outer margin of the kidney at 

 its hinder end. The vein then continues within the kidney close 

 to its lateral margin and gives off numerous branches, which 

 break up into capillaries in the kidney. At about the middle of 

 the kidney a vein comes from the side and entering the kidney 

 joins the renal portal. This is the dorsolumbar vein ; it collects 

 blood from the dorsal body wall. In the female a large number 

 of veins from the oviduct also enter the lateral margin of the 

 kidney and join the renal portal vein. 



Trace the abdominal vein back and find the pelvic veins. Follow 

 one of the pelvic veins back to the base of the leg, where it will be 

 seen to join the prominent femoral. Trace this vein forward to its 

 point of union with the sciatic vein ; trace the renal portal vein 

 to the kidney. Study the distribution of the femoral and sciatic 

 veins in the leg. Observe the dorsolumbar vein entering the kid- 

 ney in the middle of its lateral margin and study its distribution. 



Exercise 16. Draw a semidiagrammatic sketch showing the hepatic 

 and renal portal systems, together with an outline of the organs with 

 which the veins enter into relations. 



