240 



TEXT-BOOK OF EMBRYOLOGY. 



Flo. 214. Surface view of area vasculosa of a rabbit embryo of n days, van Beneden and Julin. 

 The vessel around the border is the sinus terminalis; the two large vessels above the embryo are 

 the vitelline (omphalomesenteric) veins; the two large vessels converging below the embryo 

 are the vitelline (omphalomesenteric) arteries. 



Dors, aortic root 

 and aortic arches 



Ant. cardinal vein 



Chorionic villi 



FIG. 215. Human embryo of 3.2 mm. His. The arrows indicate the 

 direction of the blood current. 



