358 



REPRODUCTION 



ductus venosus, and blood which has come from the pla- 

 centa indirectly through the liver. Considering that blood 



FIG. no. Diagram illustrating the circulation through the heart and 

 the principal vessels of a fetus. (From Yeo after Cleland.) 



a, umbilical vein; b, ductus venosus; f, portal vein; e, vessels to the viscera; 

 d, hypogastric arteries; c, ductus arteriosus. 



from the body of the fetus is venous and that blood directly 

 from the placenta is arterial, the contents of the ascending 

 vena cava are mixed when they enter the heart. The Eus- 



