138 K. S. LASHLEY AND JOHN B. WATSON 



take delight in climbing about the cage, twisting and turning 

 in all directions and making little leaps to the ground. He 

 sometimes appeared to wish to draw his mother into the play, 

 stopping in the midst of his rapid climbing and striking out at 

 her. For this, however, he was usually punished severely and 

 so he never dared to persist in it. Often when Dolly lay down 

 he would scramble back and forth across her body, but this 

 is about the only familiarity she permitted him. 



The stalking play was at first directed .toward all conspicuous 

 objects in the cage, but as the baby learned to eat solid food 

 his attention became more and more directed toward this, and 

 his play activities to center around it. In all his play there 

 appeared many of the relaxed idiot type of movements, as well 

 as purposive ones. Plate V shows this sudden undirected ex- 

 penditure of muscular energy, which was at first induced by 

 the sight of food or of any other interesting object. 



"Self imitation," so marked during certain stages of develop- 

 ment of the human infant, was almost entirely lacking. The 

 few actions which might be so interpreted were those of climb- 

 ing and leaping, in which certain movements were performed 

 repeatedly, with evident enjoyment of the activity itself. It 

 is just here that self imitation would be most valuable, since 

 the activities requiring the most accurate judgment of organic 

 stimuli are involved. In most of his play, however, his 

 interest seemed to be centered in external objects rather than 

 in the movements themselves. 



LEARNING 



Many of the little monkey's activities appeared suddenly, 

 apparently without any preliminary practice, but others, par- 

 ticularly those requiring an adaptive response, were acquired 

 only after many unsuccessful trials. New stimuli at first called 

 forth an explosive reaction such as that shown in Plate V. 

 Movements of all parts of the body were initiated, the reaction 

 being wholly non-adaptive. Those random movements which 

 resulted in manipulation of the stimulating object were repeated 

 and the others gradually eliminated. 



It is here that play seems to be of the greatest use, providing, 

 as it does, a variety of undirected activities which are grad- 

 ually moulded to meet the requirements of the environment. 



