56 



FREDERICK S. BREED 



the rectangle were constructed as nearly as possible of equal 

 areas. The regular manner of training was resumed and the 

 reactions of chicks 15, 22, and 2 3 to the circle-rectangle com- 

 bination were tested. At the risk of being tedious I present 

 the results in detail, for whether or not the ability to react 

 selectively in this case would have demonstrated the depend- 

 ence of the reactions on the element of form, it did not seem 

 unreasonable to expect the chick to develop a habit of reacting 

 differently to stimuli as different as these. 



A glance at tables 16, 17, and 18 reveals only negative results. 

 The chicks soon came to a point in these form tests where 

 they did not make an effort to escape from the box. Pre- 

 caution was taken to see that the electric shock was not 

 too severe. Previous experience in the color experiments had 

 shown that a chick occasionally received a shock of too great 

 intensity and thereafter hesitated about entering the electric 

 chambers. But the shock for nos. 15 and 23 ran as low as 6 

 to 6.5 on the scale of the inductorium, and did not reach a greater 

 intensity than 6.5 for no. 22. The regular shock, as stated before, 

 was 5.5. Just prior to the discontinuance of the tests, no. 22 

 would approach the display cards, hesitate, at times shake its 

 bill, and go no further. The expedients of moving a card over 

 the top of the apparatus from the entrance box toward the 



TABLE 16 



Reactions to Form 



Chick no. 15. Hatched 2/5, '08. Sex, Undetermined 



Circle-Square 



Series Date Right 



Wrong 



A. 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 

 10. 

 11. 

 12. 

 13. 

 14. 



