20 JOSEPH U. Y ARE ROUGH 



TABLE II 



Animal Trials 



25 120 



26 120 



27 140 



28 120 



29 120 



50 TOO 



Average 120 91 . 1 



A set of test trials was interpolated after each 20 trials of the 

 regular series in order to measure the gradual growth of the asso- 

 ciation. The average number of trials necessary to master this 

 problem was 120, but a study of the curve in Fig. 4 and the 

 records of the individuals of the group show that after 60 trials 

 some of the group held their record to and above the 90 per cent 

 mark, and that after 80 trials no animal fell below this point. 



2) One-second Interval. Group III was used in these tests. 

 The buzzer was presented one second before pain, to which they 

 had previously learned to respond negatively. If the old re- 

 sponse to pain was transferred to the sound stimulus, and the 

 animals turned around for it, no pain was given. But if they 

 failed to turn around to the buzzer and instead continued toward 

 the food-box, the pain was given at the end of one second. 

 Results are given in Table III. It was unnecessary to give the 



TABLE III 



Animal Trials 



I 118 



12 131 



22 128 



24 126 



35 148 



37 120 



Average 128.5 91.1 



special test series in this group in order to determine the gradual 

 growth of the association, for if, in the regular training series, 

 the animals failed to turn around before pain was given, the 

 response was recorded an error: if they turned at the sound no 



