10 



K. S. LASHLEY AND L. E. WILEY 



different mazes used. The groups are designated Normal and 

 Operated I, II, III, and IV, corresponding to the number of 

 the maze in which the animals of the group were first trained. 



St 



II 



II 



II 



NI5 

 Op 30 



NI5 - 



P 32 ^ 



V 



II 



NI5 

 P 3I 



IV 



S 



NI5 



On 34 



/ 



N60 

 P 125 



Fig. 1 General plan of the experiments. The four comparison mazes (actually 

 constructed by subdividing the largest) are shown at the left, the control maze 

 at the right. The number of animals trained in each maze is indicated. F, food 

 compartment; S, starting compartment; N, normal group; Op., operated group. 



METHODS 



Mazes 



For comparative tests, mazes of the general plan of 

 Lashley's maze III ('29) were used. This plan has the ad- 

 vantage that the number of blind alleys can be increased in- 

 definitely without introducing any fundamental change in the 

 general plan. It has the possible disadvantage that the cor- 

 rect path is one of simple alternation, capable of easy 



