INDIVIDUAL DIFFERENCES 



37 



by first going to the closed gate in the second compartment before 

 completing the day's record. After the position of the open gate 

 had been changed, from the right to the left in this case, at the inter- 

 ference point, i.e., the eighteenth day, the mouse tried to pass through 

 the previously open gates, but from the third day after the inter- 

 ference had been given a new rhythm was set up, which lasted until 

 the last trial, where a perfect record of no errors was made. The 

 rhythm in this case reversed the previous rhythm by the mouse try- 

 ing to pass through the closed gate in the first compartment, but fail- 

 ing to pass this gate it quickly ran around to the successful gate and 

 dashing through, continued on to the open gate in the second com- 

 partment. As will be shown in an accompanying table, it is interest- 

 ing to note that this mouse, except for the first three days of training 

 and the first two interference days, made only a single error on any 

 one day. In Table X. are given the daily error records for the same 

 two mice, Nos. 131 and 132, that were made in the maze test. The 

 left half of the table gives the complete record for No. 131, while 

 at the right is given the record of No. 132. The first column gives 

 the number of days and indicates the extent of each learning period ; 

 the second column, the number of times that each mouse tried to 

 pass through the closed gates in each compartment (if two numbers 

 are given for any one day the upper number represents the errors 

 in the first compartment and the lower one errors in the second com- 

 partment) ; while the third column gives the number of trials made 



