REVERSIBILITY OF HELIOTROPISM OF ARENICOLA LARV/E. 159 



TABLE IV. 



EFFECTS OF ALCOHOLS. 



those obtained with alcohols. In no case, however, were the 

 larvae normal in behavior when the temperature was lowered 

 either 5 C. or 10 C. below room temperature. On the other 

 hand, production of negative heliotropism at the higher tem- 

 perature (32) was much more striking with the esters than with 

 any of the alcohols. Table V. gives a summary of these series 

 of experiments. 



TABLE V. 



EFFECTS OF ACETONE AND ESTERS. 



From Tables IV. and V. nothing certain can be concluded as 

 to the temperature coefficient in the production of negative 

 heliotropism, although the time needed to reach the maximum 

 point is about halved by a rise of 10 C. 



