244 



JOHN D. DODSON 



TABLE 2 Continued 



Special conditions of series II. The strength of the electric 

 shock used for the second series was two hundred and fifty units; 

 and the length of period of hunger was thirty-one hours. 



Results. Detailed results of the above series of experiments 

 are given in tables 1 to 4. These tables also give the results of 

 the retraining of the same subjects after a period of twenty-one 

 days from the day on which each animal perfected the habit. 

 The retraining of each group of rats was done under the same 

 conditions as the training, and the habit was considered re- 

 established when the subject made ten successive right choices. 



Construction of tables. At the top of each table are the num- 

 bers of the subjects (even numbers refer to males and odd to 

 females) trained under the conditions stipulated in the heading 

 of the table. The first vertical column gives the number of the 

 training series; the vertical columns marked W give the number of 

 errors made by the subjects in each training series; columns 

 marked Av. T. give the average time for the choice of the indi- 

 viduals; columns marked Av. E. give the average number of 

 errors made by males and females (according to which the 

 column follows) ; the column marked Gen. Av. in each table 

 gives the general average of both males and females; and the 

 column marked total Av. T. gives the general average time for 

 choice of both males and females in each table. 



