2SS ARTHUR C. WALTON 



usual result was that the compartment that was discriminated 

 the least accurately received a few more trials than the others. 



Another point gained from the records is that the reaction 

 comes, not from seeing a light over a compartment and then 

 going there when released, but from the fact that when a light 

 was shown over a certain compartment to which he had been 

 trained to go on stimulus, the dog went as a matter of habit. 

 Hence, a light over a compartment to which he was not in the 

 habit of going did not set up in the dog's mind the association 

 of "Light — Movement to Light — Food" or for the incita.tions 

 to the motor response that comes on release, that the training 

 to that compartment would. The dog must be in the habit, 

 gained through thorough training, of going to an indicated 

 compartment on release, or he would not pay any attention 

 to it, but on release would go to one of those to which he was 

 accustomed to go, even though he had received no stimulus 

 to go there. The mechanical is stronger than the reasoning 

 in this case. Addition to the number of compartments means 

 that the dog must have special training on the new one before 

 it can become one of the several to which he is trained to go on 

 release after a stimulus had been given. 



In the "Three Light" problem, condition "A" shows that 

 by course of long training a light stimulus can be made effective, 

 and the dog can remember the cues formed and the associations 

 set up by the light stimulus for the three compartnemts over 

 a period of one minute delay between stimulus and release. 

 The latter part of the records show that the olfactory stimulus 

 to reaction was not an important factor, as the records were 

 as good as when the presence of the food in the bowl gave the 

 possibility of such stimulus. 



The records from Condition "B" show that the sight of the 

 operator placing the food in the bowl and operating the lights 

 gave no cue that was necessary for correct reactions, as the 

 general results of "B" are practically the same as those of "A" 

 while the dog could not see the operator until after the entire 

 reaction had been completed. 



Condition "C" gives results of the effect of orientation and 

 the retaining of the compartments in view during delay period, 

 on the correctness of reaction. The records show that the dog 



