26 L. W. SACKETT 



use the mouth in Hfting food. How long this would have per- 

 sisted unfortunately can not be known, for No. 8 died soon 

 after this part of the experiment was completed. 



No. 9 acquired equal facility in this line but after much 

 greater effort, and even then the habit was not exercised very 

 freely in remote parts of the cage. No. g would also revert to 

 the natural method of feeding the moment the experimenter's 

 attention was diverted. This tendency to lapse to the more 

 primitive type of beha^4or is seen whenever the animal's train- 

 ing does not conform to his natural habits. Even the celebrated 

 chimpanzee "Peter" drops on all fours under intense excite- 

 ment or when his keepers are not observing closely. The habit 

 of picking up food with the hands did not persist in any marked 

 degree with porcupine No. g, although this animal employed the 

 hands in other experiments more than is customary with the 

 porcupines and occasionally grasped food found in the cage, 

 raising it to the mouth with one hand. Whether this was a 

 mere coincidence of individuality, or the result of a permanent 

 modification of behavior, is uncertain, though the latter seems 

 to be far more probable. 



No. 9 was then set the task of handling a cup in one hand 

 and taking food from it with the other hand. Porcupines do 

 not need to be taught to hold a cup or box in both hands and 

 take the food from it with the mouth, as they frequently seize 

 the food-boxes in that manner if an opportunity is afforded. 

 But this different use of the two hands involved a new co-or- 

 dination, one which is not seen in an untrained animal unless 

 it be the same co-ordination necessary in holding down branches 

 of trees and picking off fruit, but even here the mouth is used 

 to pull food off' and the free hand to assist in getting it into the 

 mouth. The mental side of the association became well estab- 

 lished but the muscular co-ordination was not so well perfected. 

 The cup merely hung from the hand and was not held up as 

 we hoped it would be. This may be accounted for either by 

 the fact that the cup was unsuited to the hand, or the hand 

 was not suited to this kind of adjustment. 



More than six months later this same animal was again tested 

 on the tendency to pick up food with the hands. There had 

 been no analogous training during that time. Many times 

 when food was offered the animal it had reached with its hands, 



