GERMINAL LOCALIZATION IN THE EGG OF CEREBRATÜLUS. Ï3 





a-Cllt' 



b-cut 



[3 perfect. 

 [2 defective. 



3 fairly normal. 



1 pilidium with small gut 

 (Fig. 10 a, A). 



2 auenteria (Fig. 10 b, B). 



c-cut(2 perfect. 



From this experiment it will 

 be seen that the cuts a and c pro- 

 l^iG. 9. cluce little or no malformation at 



Diagrams of the operation in all, while the cut b is liable to 

 ^"^^^^^ cause larvie with a small enteron 



or none at all. This may show that the localization of the 

 ento- and ectodermic bases has advanced a great deal by this 

 time. It is also worth noting that the formation of the ciliated 

 lobes is somewhat disturbed by the cut b at this period. 



EiG. 10. 



A and B, two pilidia arising from the operatinii'^ as indicated in a and 

 b respectively. 



