236 T/ie Dancing Mouse 



white box immediately ; in the latter, it rushes from the black 

 box into the white one without hesitation. So much evi- 

 dence the discrimination tests furnish of forms of behavior 

 which in our fellow- men we should interpret as rational. 



Comparison of the error curves for the labyrinth tests 

 (Figures 26 and 31) with those for the discrimination tests 

 (Figures 29 and -30) reveals several interesting points of differ- 

 ence. The former fall very abruptly at first, then with de- 

 creasing rapidity, to the base line ; the latter, on the contrary, 

 fall gradually throughout their course. Evidently the laby- 

 rinth habit is more readily acquired by the dancer than is the 

 visual discrimination habit. Certain motor tendencies can 

 be established quickly, it would seem, whereas others, and 

 especially those which depend for their guidance upon visual 

 stimuli, are acquired with extreme slowness. From this it 

 might be inferred that the labyrinth method is naturally far 

 better suited to the nature of the dancer than is any form of 

 the discrimination method. I believe that this inference is 

 correct, but at the same time I am of the opinion that the 

 discrimination method is of even greater value than the 

 labyrinth method as a means of discovering the capacity of 

 the animal for modification of behavior. 



Inasmuch as my first purpose in the repetition of white- 

 black discrimination tests with a number of individuals 

 was to obtain quantitative results which should accurately 

 indicate individual, age, and sex differences in the rapidity 

 of learning, it is important to consider the reliability of the 

 averages with which we have been dealing. Possibly two 

 groups of five male dancers each, chosen at random, would 

 yield very different results in discrimination tests. This 

 would almost certainly be true if the animals were selected 

 from different lots, or were kept before and during the tests 

 under different environmental conditions. But from my 



