152 MALL. [Vou. XIX. 
Fic. 13b.—Section through the amnion, jugular veins, umbilical vesicle 
and chorion. XX 30 times. 
Fic. 13¢.—Section through the umbilical vesicle as it joins the chorion. 
x 30 times. The large irregular space in the chorion is a blood space 
which communicates with the veins of the embryo. 
Fic. 13d.—Embryonic vesicle ‘attached to the chorion. * 20 times. After 
His. 
