240 



EDWIN <:. BORING 

 TABLE III 



for either side. D was injured and had to be discarded. B 

 was still fatigued. After approximately four days B showed a 

 slight preference for the left. 



REVERSAL OF REACTION 



It has already been noted that the planarian under directive 

 light frequently turns abruptly toward the source of illumina- 

 tion in a manner, which, by reason of its quickness and sudden- 

 ness, is quite different from the slower continuous turning from 

 the light. Although less markedly, the animal also tends to 



