VISUAL PERCEPTION OF THE CHICK 



79 



the stimuli was an original factor determining the choosing. 

 Thus, among the individual native tendencies that may have 

 existed with these different chicks as influences in forming 

 the habits demanded by this problem, the tendency of right 

 or left choosing appears to be most pronounced. 



TABLE 13 

 Preliminary Series 



With the twentieth test the two preliminary series ended 

 and thereafter the training series began. At this point the 

 chicks, instead of being allowed to escape where they chose, 

 were required to escape from the compartment where the + 

 stimulus was displayed. The animals were aided in releasing 

 the tripping device, because they lacked sufficient weight; but 

 the experimenter could not cause a release of the exit door 

 until the chick stood in the proper place, when a pull on the 

 silk line released the tension of the lifting spring so that the 



