20 FREDERICK S. BREED 



Spots on the card runs thus in its first test, as detailed above : 

 I-I-I-I-2-I-I-I. Table 2 shows the accuracy of its pecking 

 from Dec. 13 to Dec. 26. 



TABLE 2 



Chick no. 7. Dec. 13-26, 1907. Pecking 



Date 13 14 16 17 18 19 20 21 24 26 



Missed 1 



Struck 7 5 2 3 17 1 2 



Seized 3 3 1 2 1 1 1 



Swallowed 17 13 12 17 14 19 13 18 19 17 



Chick no. 14, as just stated, had been placed in the same 

 enclosure with no. 7 at the same hour on the same date, and was 

 kept there till 4:25 p. m., Dec. 11. After 38 hours and 55 min. 

 thus enclosed, it was tested in the same way as no. 7. On the 

 first pecking attempt it pushed its bill, mandibles closed, into 

 a bread crumb. Then followed six pecks that missed. Attempted 

 to scratch its head and lost its balance. Seemed weaker than 

 the other chicks. Pecked toes and bare black cardboard; 

 scratched bill. A second time it pushed its bill slowly into a 

 bread crumb. Then followed a reaction in which it missed, etc. 

 The summarized record for this test appears thus: 2-1-1-1-.1- 

 1-1-2-1-2-2-1-2-2-2-2-1-3-2-2-2-2-3-2-2-2. The accuracy of 

 its later pecking, Dec. 13 to Dec. 26, is shown in the follow- 

 ing table: 



TABLE 3 



Chick no. 14. Dec. 13-26, 1907. Pecking 

 Date 13 14 16 17 18 19 20 21 24 26 



Missed 1 1 



Struck 96 12 65 341 



Seized 2 1 1 1 1 2 



Swallowed .... 9 13 8 13 14 20 19 16 14 18 



A comparison of the records of these three chicks for Dec. 

 13 with the corresponding records of five others of the same 

 age which were not subjected to confinement in darkness shows 

 that there was no noteworthy difference in the development at 

 this time. The averages of the three chicks on the above 

 date were .7, 4, 2, and 13.3 for reactions i, 2, 3, and 4, respect- 

 ively, while the other five chicks averaged .8, 1.4, 4, and 13.8 

 for the same reactions, in a total of twenty reactions. On the 



