358 'Journal of Comparative Neurology and Psychology. 



of the box in order to get food, he put the male monkey in the 

 box with her. "Knowing the trick perfectly he seized the end of 

 the plug with his teeth and removed it. I set the box again. This 

 time the female rushed to it, seized the plug by the end as the male 

 did, and procured the food. This she repeated immediately eight 

 times in exactly the same way. On succeeding days she removed 

 the plug as a part of a combination lock on the same plan, 130 

 times. Recalling that she had failed to work the bear-down lever 

 for opening the box. . . I placed it before her. She rushed up, 

 but missing the plug she sat down. The male passed her, pushed 

 the door down and procured the food. When the box was set 

 again she worked the lever and took the food in the same way that 

 he had done. She manipulated the apparatus several times 

 immediately, and 250 times later as a part of a combination lock. 

 Besides these, once when the male peeped under the bottom of one 

 of the trees, the female came and peeped in the same manner."^ 



Commenting on these results, Kinnaman says: "It seems to me 

 that the two cases with the box are quite as good examples of 

 imitation as could well be gotten even with human beings. While 

 this is an unusual method ot learning on the part of the rhesus, 

 the above example seems to me conclusive evidence that it is at 

 least a possible method for him."- 



I entirely agree with Kinnaman that here w^e have a clear case 

 of intelligent, voluntary imitation. I also agree with Thorndike 

 and Small in regard to the interpretation of their results, as I 

 think that all the apparent cases of imitation brought out in their 

 experiments can be explained as automatic or instinctive imitation. 

 From the fact that the results of their experiments were negative 

 so far as voluntary imitation is concerned, it does not necessarily 

 follow, however, that voluntary imitation does not exist in these 

 animals. It may be that the conditions of their experiments were 

 not favorable for imitative action. 



So much for what has been done in this field by previous inves- 

 tigators. Now let us turn directly to a discussion of our results. 



We found that when two rats were put into the box together, 

 one rat being trained to get out of the box, and the other untrained, 

 at first they were indifferent to each other's presence, but as the 



'Kinnaman. Mental Life of Rhesus Monkeys in Captivity. American Journal of Psychology, Vol. 

 13, p. 121. 1902. 



"Same article, p. 122. 



