276 



THE BIOLOGY OF THE FROG 



CHAP. 



behind the crest of the ileum. The femoral vein branches 

 in front of the base of the thigh into two parts, one of which 

 passes ventrally and joins its fellow of the opposite side to 



Fig. 77. — The hepatic portal system, showing its relations to the stomach, 

 intestine, pancreas, and hver. a\ branch from the anterior abdominal 

 to the portal vein ; ant.ab, anterior abdominal vein ; du, duodenum ; 

 du' , artery to same; g, gastric vein; g.bl, gall bladder; Iv' , Iv" , right 

 and left lobes of the liver respectively; /, portal vein; pc, pancreas; st, 

 stomach. (After Howes.) 



form the anterior abdominal vein, which runs forward in 

 the middle of the ventral body wall ; the other branch, the 

 external iliac, passes forward, and dorsally, and joins the sci- 

 atic vein to form the commo7i iliac or renal portal vein, 

 which runs forward along the outer margin of the kidneys, 

 into the substance of which it sends its branches. The renal 

 portal receives the dorso-liunbar vein, from the body wall, and 



