78, 



THE FETAL MEMBRANES AND EARLY HUMAN EMBRYOS 



cut away. Embryos with 9 and 14 pairs of segments, with three brain vesicles 

 and with the amnion cut away are seen in Figs. 81 and 324. The relation of the 



. I 111 }i ion 



Body stu. 



Fig. 82. — Human embryo of about 2.5 mm. (His, after Coste). X 15. 



fetal appendages to the embryo shows well in the embryo of Coste (Fig. 82). 

 The dorsal concavity is probably abnormal. A robust body stalk attaches the 



A III 111 « 



Branchial clef Is 1-3 



Body stalk 



Ma,\ illiiry process 



Yolk-sac 

 Fig. 83. — Human embryo 2.6 mm. long showing amnion, yollt stalk and body stalk (His). X 25. 



embryo to the inner wall of the chorion. With the growth of the head- and tail 

 folds of the embryo, there is an apparent constriction of the yolk sac where it 



