THE DIFFERENTIATION OF SPECIES. 



73 



! 



s . 



1-H 



!" 

 I 



Jli 



^. co w 



II 



lo 



11' 



|J 



o 



w 

 EC 





I 



I! 





w 

 

 w 

 O 





I! 



rt 





s 



s 



^ 3 



* 2 



W 



, 



N 



3 S g 



f 



X 



