LEARNING IN THE MONKEY 259 



imitation.) After that they all promptly used the lower space 

 and abandoned the wires for reaching food from this box. They 

 seem to be equally quick at it, often requiring only about one- 

 half a second to make the movement. 



The food box was then presented to D, E and F, who were 

 caged together. D, E and F saw A, B and C feed from the 

 box and F may have imitated them, but since he had often 

 reached to the floor before, this is not likely to have been the 

 case. He immediately placed himself in the proper position 

 and reached the food. D and E could not reach the food, 

 although they extended their hands through the proper aperture. 



Before relating D and E's methods of finally acquiring the 

 food from the box it is necessary to make clear the type of 

 movement required to reach the food. The extreme simplicity 

 and naturalness of the position necessary to acquire the food 

 should be given the most consideration. 



To take a nut from the box the movement of A, B, C and 

 F was simply that of crouching close to the floor on all fours 

 with the body parallel to and near the aperture, then extending 

 the forearm of the arm nearest to the bar through this aperture, 

 pronating the hand so that the palm faces the food and simul- 

 taneously pushing the arm through the aperture up to the shoul- 

 der. A, B, C and F did this within a few seconds from the 

 beginning and quickly became so expert that they could per- 

 form the movement in less than a second. All monkeys learn 

 this crouch in infancy, as do most four-footed animals. It 

 is one of their most natural and frequent positions. To crouch 

 on the perch in this manner and reach over the edge with one 

 hand to scratch another monkey below is a very frequent move- 

 ment for all of them to make. So in this movement probably 

 no new motor coordinations were required or sensory stimuli 

 given, and on the other hand one of their most frequent posi- 

 tions and movements was necessary to reach the food. One 

 thing must be added, however. When the monkey's head re- 

 mained above the cross bar and near the wire netting he could 

 see the food while he reached for it; and when he crouched close 

 to the floor and extended his arm through the aperture beneath 

 the cross bar, his face would be beneath the cross bar, and he 

 would be unable to see the food or his hand when he reached. 

 He would have to depend upon touch to orient himself. On 



