174 BINNIE D. PEARCE 



TABLE 4 

 Correct Reactions in Each Succeeding 50. Habit No. 2 



Rats 



are not to be explained by variations in age (which were too 

 small) or in experimental conditions. The essential factor is the 

 interference of habit No. 1 with the formation of habit No. 2. 



The following is a brief examination of representative data 

 secured on habit No. 2. Rat No. 3 had acquired the first habit 

 with great facility after 80 trials. After 1160 trials on the 

 second association he was making only 31 correct reactions out 

 of a possible 50. This rat when set upon the new problem was 

 in perfect condition and had shown no tendency to untoward 

 timidity or the formation of position habits. When presented 

 with the second problem, he at first reacted to the stimuli (8- 

 c.p. light for turning to left; darkness for turning right) as if 

 they had been the former stimuli (32-c.p. light for turning right 

 and darkness for turning left). Upon punishment he imme- 

 diately set up position habits from which he could be forced only 

 with difficulty and into which he fell again and again. Several 

 times he slowly approached the standard of learning; but when 



