The Frog 



61 



as well as from the innominates which collect blood from the head by 

 means of the internal jugulars and from the shoulder by means of the 

 subscapulars, and the subclavians which collect blood from the fore limbs 

 by means of the brachial, and from the side of the body and head by 



Sino- auricular 

 opening ~ ' 



Pulmonary 

 vein 



R. precaval 

 svem 



Liver - 



£rternd jugular win 

 Innominate vein 

 -Subclavian vein 

 - -Brachial Vein 



--Hepatic vein 



Musculo - 

 '" cutaneous v. 



_ Hepatic 

 portal v 



Kidney - - 

 Testicle - - 



Abdominal v - - 

 'Renal veins - - 



Transverse iliac vein 



^-Postcaval v 



——-Mesenteric v. 



Dorso- lumbar 



veins 



Renal portal v. 



—Pelvic uein 

 Femoral v. 

 Sciatic v 



Fig. 14. The Venous System of the Frog. 

 (Modified from Meissner.) 



Note that the blood returning to the heart from the posterior limbs must do one of two things: 

 (1) It must pass through the kidney (renal portal system), or (2) it must pass, by way of the 

 abdominal vein, through the liver (hepatic portal system). In either case, it enters the sinus venosus 

 by way of the postcaval vein, and from there to the right auricle through the sinu-auricular opening. 



means of the musculocutaneous veins. The posterior vena cava receives 

 blood from the liver by means of two hepatic veins, from the kidneys by 

 means of four to six pairs of renal veins, and from the reproductive 

 organs by means of spermatic or ovarian veins. 



