DISTRIBUTION OF EFFORT IN LEARNING IN WHITE RAT 45 



are necessary, and probably many more animals will have to 

 be employed. 



RETENTION TABLE I 

 Latch Box Alone 



The group showing the best average on the retention test is marked with an X. An X is also 

 for convenience in reading placed before the figures showing the average. 



TABLE II 

 Latch Box with Two Other Problems 



TABLE III 

 Maze Alone 



