INTERFERENCE OF HABITS IN THE WHITE RAT 



65 



100 trials of the 30-day test with B. It will be seen from this 

 table that there is no essential difference between the initial 

 stages of the two habits. 



TABLE 9 



IX 



Conclusions. — The present paper opens up problems in an all 

 but unexplored field of animal behavior. Keeping in mind the 

 limitations imposed by the number of animals and the type of 

 experiment, the following conclusions may be stated as the 

 more important ones to which our work points: 



1. Habit interference occurs in the white rat between a first 

 habit and the formation of a second one. 



2. This interference may or may not manifest itself at the 

 beginning of the second habit and may or may not manifest 

 itself later during the second learning. 



3. ' Interference ' is most marked between the end of the 

 perfected habit and the beginning of the new habit. In many 

 cases this may show not genuine interference, but merely the 

 beginning of a new habit. 



4. Habit interference may serve greatly to slow up the forma- 

 tion of a new habit. Clear evidence of this forward reference 

 has been found. We have brought to light no evidence that 

 learning the second habit as such interferes with the retention 

 of the first habit. 



5. It seems clear that in some cases the lapse of time may be 

 more effective than intervening training in disintegrating a habit. 



