THE BEHAVIOR OF THE CROW 197 



3 centimeter circle was presented with the 5 centimeter circle, 

 the crow reacted to the 3 centimeter circle thirty-seven times 

 negatively and. three times positively. On August 26th, the 3 

 centimeter circle, displayed with the 2 centimeter circle, was 

 reacted to positively in every case. The results for crow no. 1 

 with the 6 centimeter circle when displayed with the 4 centi- 

 meter and the 9 centimeter circles, on August 26th and 27th, 

 were almost as decisive. 



TABLE 3 



Reactions to Relative Sizes of Circles 



Correct choices 

 Date No. of tests Crow No. 1 Crow No. 2 



Relative reactions, 3 centimeter — 2 centimeter circle 

 Aug. 26 5 5 5 



" 26 5 5 3 



Training series, 6 centimeter — 4 centimeter circle 

 Aug. 26 10 7 9 



Relative reactions, 9 centimeter — 6 centimeter circl 

 Aug. 27 5 4 2 



" 27 5 5 3 



Training series, 6 centimeter — 4 centimeter circle 



Aug. 27 8 2 ' 5 



"28-10 6 8 



" 28 8 5 3 (Righ habit) 



"29 5 4 .4 



" 29 5 4 3 



" 29 6 5 5 



Relative reaction -, 3 centimeter — 2 centimeter circle 

 Aug. 30 5 5 2 



" 30 5 5 4 



Tra ! ning se.ies, 6 centimeter — 4 centimeter circle 

 Aug. TO 5 5 2 



Relative reactions, 9 centimeter — 6 centimeter circle 

 Aug. 31 5 2 4 



" 31 5 4 3 



Only one day intervened between the conclusion of the tests 

 of the relativity of the reactions and the beginning of experi- 

 ments to determine the ability of the crow to distinguish circles 

 from triangles, squares and hexagons. ' 



With the beginning of this study of form perception the 

 experimenter became more convinced than ever that the results, 

 obtained in the previous experiments, did not truly indicate the 



