62 



HAROLD C. BINGHAM 



lest the chick should not remain in good physical condition, but 

 at its conclusion the bird was in excellent health, having out of 

 doors range, so the work was repeated with more thoroughness. 

 The last two series (24 and 25) of table 7 were introduced as 

 a different sort of control tests. The circle was larger than the 

 triangle, hence it afforded an opportunity to see if the chick 

 would react to form difference, after this training, rather than 

 size difference. Apparently it was demanding too much of the 

 chick for it became discouraged at this point and the training 

 had to be repeated. 



No. 21. 



TABLE 7 



Form Perception 



Hatched: February 9, 1912. 



Sex: 9 



In table 8 are presented the results of the re-training of No. 

 21. While the record, as shown in the table, indicates that 

 the chick discriminated between the triangle and the circle, 

 it is, nevertheless, equally convincing that the chick did not 

 perceive the form difference. It had reacted properly to the 



A 28 H (D 19+ and — 23+ when the apex of the triangle 



was at the top, but when the triangle was inverted (series 20, 

 March 25), the animal did not choose the triangle more than 

 half of the time. With the triangle again upright, the correct 

 reactions returned. Proper responses were made when the 



