RESPONSES TO LIGHT OF THE ROACH. 



375 



TABLE II. 



SHOWING THE ABILITY OF ADULT MALE ROACHES TO LEARN TO AVOID ENTERING 



A SPECIFIC DARK PLACE. 



DESCRIPTION OF THE EXPERIMENTS. 



The roaches used in these experiments were kept, in solitary 

 confinement, in jelly glasses. A piece of damp sponge supplied 

 the necessary moisture and food was added from time to time. 

 In some cases sand was placed in the bottom of the tumblers. 

 As frequently as necessary the glasses were cleaned. When the 

 time for the experiment arrived the roach was transferred from 

 this jelly-glass to either the middle compartment of box number 



