102 EUPHA FOLEY TUGMAN 



bird began to discriminate them again. The previous behavior 

 was evidently due to inability to make the discrimination. 



Female VI was more calm than any of the other birds. Her 

 behavior was even more satisfactory than the behavior of Male 

 IV. After Female VI learned the first problem, to choose the 

 darker of the two lights, she would move about very slowly and 

 deliberately. She would hesitate in the doorway of the entrance 

 chamber for a few seconds, then hop out into the discrimina- 

 tion box. She would hesitate several seconds looking a while 

 to one side, then turning her head and looking to the other side. 

 Presently she would hop on to the side she had chosen and into 

 the alleyway. She was always slow making a choice and gave 

 good results all through the experiment. 



The nervous birds gave the poorer results. 



Cole 13 thought the chicks which were most sensitive to the 

 electric shock learned more rapidly under the influence of weak 

 stimuli. The most sensitive sparrows did not learn most quickly. 

 The two birds which gave the best results, Male IV and Female 

 VI, both required a heavier shock than the other two birds. It 

 was not necessary to shock them frequently. But when it was 

 necessary, the observer had to give them almost twice the 

 strength of current that was given the other birds. As stated 

 before, the final results differed widely. Male V and Female V 

 failed to discriminate lights with which the other birds had no 

 difficulty. The observer thinks that Male V and Female V were 

 inferior to the other two birds in acuteness of vision and prob- 

 ably in mental capacity also. 



(b) Influence of former experiences. At first the birds were 

 greatly influenced by their former experiences. They would 

 tend to respond in the same direction as in the immediately 

 previous test, provided they had not received a shock. If they 

 had just received a shock they would nearly always go to the 

 other light in the following test. But after the birds learned 

 the problem their judgments were founded on visual discrimina- 

 tion and they were not guided much by previous experience 

 except when they acquired the position habit. 



(c) Position habit. The thing that gave the experimenter 

 the most trouble was the tendency of the birds to get the posi- 



13 Cole, L. W. The Relation of Strength of Stimulus to Rate of Learning in 

 Chicks. Journal of Animal Behavior, Vol. 1, No. 1, 1911. Page 111. 



