20 



STELLA B. VINCENT 



number of trials in learning was one-third less and the total 

 number of errors was reduced in the same proportion. The 

 brightness situation must have been responsible for these con- 

 trasting results. The lengthened period of training on the maze 

 before attempting the problem box may account for its greater 

 effectiveness in this case. 



Although the conduct described above was influenced by 



Fig. 8. 



Curves of the blind rats in the black-white maze 

 Time, Errors 



brightness, may there not have been a preference, either in- 

 stinctive or acquired, for black or for white ? It must be 

 remembered that the animals in the experiments described may 

 have been reacting to one color only regardless of any changes 

 in the maze. 



We do not think the reactions were due to preference. If 

 they had been, there would have been greater differences be- 

 tween the results of the experiments where the true path was 



