RESPONSES TO LIGHT OF THE ROACH. 



381 



females (Fig. 2, A). The quickest to learn of all of the roaches 

 investigated was a male (Fig. 3, C). Ranking next to this male 

 came an adult female with amputated antennae (Fig. 6, A). 

 Indeed the most striking thing in these investigations is the 



a 



S~ 10 IT IQ if 30 



to v-y 



ff 60 t>r ?o 



a 



a 



a 



C 



f 10 If i.0 if 30 3T 40 1-f 



D 



b f to if o f 30 3r fo r ro rr 60 jr 70 



B 



ff 60 



90 



f to if 20 if jo jy to ts n &~f to t>f TO 



F 



FIG. 3. Reaction curves of five adult male roaches. The numbers represent 

 opportunities to make a choice; a represents refusals to enter the dark chamber, 

 b represents entrances into the dark chamber. 



marked individuality of the roaches. A glance at the few re- 

 action curves published herewith (Figs. 2-6) will serve to empha- 

 size this statement. 



