468 



WILLIAM A. HILTON 





II 



U 



c 



Fig. 8 Central nervous system of A. erectus during first larval stage. X 350. 



Fig. 9 Nervous system of A. erectus during the second larval period. X 350. 



Fig. 10 Section through whole larva of A. erectus during the third larval 

 period. X 350. 



Fig. 11 Central nervous system of A. erectus at about the third larval stage. 

 Drawn from a whole mount which did not show as much as some others. X 300. 



Fig. 12 Longitudinal section through the central nervous system of A. erectus 

 during the last larval stage. X 350. 



Fig. 13 The central nervous system of the first larval stage of Ammothella. 

 X 350. 



