38 WALTER S. HUNTER 



Preliminary tests insured an absence of emotional disturbances 

 in the reactions. 



The animals tested under these conditions were : Rats 1 3 , 

 15, 16 and 17 (No. 17 was the only one tested with a choice of 

 three boxes) ; both dogs (Brownie alone was tested with a 

 choice of three boxes) ; raccoons Jack, Jill and Bob (Jill alone 

 was tested with three boxes). 



Table 6 gives a comparative statement of the animals' abil- 

 ities with large and small release. Both records for each animal 

 are for discriminations with the same number of boxes. It 

 will be seen from this that rat No. 13, the dog Blackie and the 

 raccoons Jack and Bob are the only ones that failed to delay 

 longer with the large release. This fact can be readily explained 

 in the case of Jack and Blackie. The experimenter was prim- 

 arily interested in discovering whether any new mode of be- 

 havior would appear under these conditions. When this ques- 

 tion was answered, tests were discontinued with all the animals 

 although in the case of Jack and Blackie the interval of delay 

 was being steadily increased. The increase in delays made by 

 the other animals is to be correlated w4th the changed condi- 

 tions of experimentation. This point will be amplified when 

 the detailed behavior of the animals is discussed. 



TABLE VI 

 Small release Large release 



Per cent of Per cent of 



Animal Delay correct reactions Delay correct reactions 



Rat No. 13 4 sees. 88 3 sees. 95 



Rat No. 15 1 sec. 86 6 sees. 86 



Rat No. 16 1 sec. 50 9 sees. 82 



Rat No. 17 7 sees. 68 1 sec. 37 



Blackie 5 mins. 80 1 min. 80 



Brownie 2 sees. 68 6 sees. 96 



Jill 3 sees. 93 7 sees. 80 



Jack 20 sees. 85 15 sees. 88 



Bob 25 sees. 90 20 sees. 76 



(c) Effect of backgrounds of different brightnesses upon the 

 interval of delay. — When the apparatus for the animals was 

 constructed, every effort was made to secure qualitative simi- 

 larity in the three light boxes. The backgrounds surrounding 

 the entrances to the light boxes were all of the same brightness. 

 During the course of the tests, the attempt was made to deter- 



