544 



AMPHIBIA. 



Inferior 

 vena cava. 



II. The inferior vena cava begins between the kidneys, and 

 ends in the sinus venosus. Its components are as follows : — 

 Efferent renal veins from the kidneys. 

 Genital veins from the reproductive organs. 

 Efferent hepatic veins from the liver. 

 The renal portal system, by which venous blood from the 

 posterior region filters through the kidneys on its way back 

 to the heart, is as follows on each side : — 



-sscp 



Fig. 182. — Venous system of Frog. (After Ecker. ) 



till., Mandibular and lingual; £J., external jugular ; ij., internal 

 jugular; s.scp., subscapular; hi., innominate; s.c. subclavian; 

 br., brachial; tiicu., musculo-cutaneous ; hv., hepatic vein; /i./r'., 

 hepatic portal ; G., gut ; a.a., anterior abdominal ; r/>., renal porta! ; 

 /?'., pelvic; A'., kidneys ; sc, sciatic ; y., femoral ; dL, dorso- 

 lumbar ; iz'C, inferior vena cava ; vc, cardiac vein. 



'A posterior branch of the femoral vein from 



the hind limb forms the renal portal vein, 



Renal portal j which receives the sciatic from the back of 



system. | the leg, and the dorso-lumbar veins from 



the dorsal wall of the body, and oviducal 



\^ veins in the female. 



The anterior branch of the femoral vein is called the 



pelvic, and unites with its fellow of the opposite side, and 



