146 Journal of Entomology and Zoology 



is not altogether borne out by the facts. But I believe that the 

 primary condition of a nervous system was superficial and sensory, 

 as development seems to show and as the study of echinoderms 

 seems to indicate. 



In the brain some functional divisions are easy to make out in 

 segmental animals, because certain pure sensory nerves are more 

 easily traced. 



14. I believe there are certain advantages in the study of simple 

 types of nervous systems. 



15. Almost every form so far examined is worthy of re-exam- 

 ination in connection with the solution of general problems. 



(Contribution from the Zoological Laboratory of Pomona College) 



