VISUAL PERCEPTION OF THE CHICK 



65 



results, table 9, the early records are omitted since these tests 

 were made only as a means of getting a discrimination between 

 the later forms. The size of the circle was gradually decreased 

 from o 63 + to © 38 + at which point the tabulation begins. 

 About 400 tests between April 1st and 20th were necessary to 

 bring the chick to the point in its training at which the records 

 of the table commence. 



Table 9 shows that the chick was able to acquire the circle- 

 triangle habit. The plan of controlling the qualities other than 



TEST SHEET 



Title of investigation, Form: A 28H O 63+ 



Experimented on, 21 



Harvard Psychological Laboratory, March 18, 1912 



Record Sheet, 2; Series, 25 



6-4-84.6 



form was carried out as heretofore explained. After No. 21 had 



acquired the o 28-| A 28 -f reaction, the order shown in 



in the table was followed to determine whether or not the bird 

 actually depended upon form difference. If it had a perception 

 of form such as has been found to exist for size, then no marked 

 change in the results should have occurred when o 28 + was 

 replaced by a circle that circumscribed or inscribed the standard 



