152 M. !•'. WASHBURN AND EDWINA ABBOTT 



Nose) were tested alternately, four tests being made with each 

 on a single day. The rabbit to be tested was admitted to the 

 yard from the hutch door, The experiment box was placed 

 opposite the hutch door, about five feet away from it. As the 

 hutch door was nearer the left side than the middle of the hutch, 

 it was impossible to place the experiment box in such a way 

 that the rabbit should not enter the yard more nearly opposite 

 the left than the right hand door of the experiment box. This 

 fact seemed to have no effect, however, in producing a tendency 

 to push the left hand door oftener than the right hand one. 

 After one rabbit had finished a test, it was driven back into the 

 hutch, and the gravel on the floor of the yard was raked over, 

 to prevent the second rabbit's being guided by the smell of food 

 on the ground where the first rabbit had been eating : the second 

 rabbit was then admitted to the yard for a test. The series 

 made with Polly in the autumn of 191 1 were carried on in the 

 same way, except that no other rabbit was being tested at the 

 same time. In the experiments performed in the laboratory 

 room, the rabbit to be tested was taken alone into the room and 

 dropped about three feet in front of the experiment box, which 

 stood on the floor. This method of confronting the animal 

 with the box is not in general to be recommended, as uncon- 

 sciously the experimenter might give the rabbit an impulse 

 toward one or the other door. But since the results of these 

 series confirmed those obtained under the other circumstances, 

 and since under both conditions the discrimination was acquired 

 in the case of red and grey and not acquired in the case of red and 

 black, no such error seems to have been involved. 



II. SUBJECTS. 



Our first subjects were two young brown rabbits, a male, 

 Light Nose, and a female, Dark Nose, obtained from a dealer 

 in animals and probably born in captivity, though upon this 

 point the dealer could not enlighten us. Nor did we know 

 their age, but they were neither full grown nor sexually mature. 

 We began our work with these on November 18, 1910. The 

 experiments with the female continued until June 12, iqii, 

 with three interruptions, one of eighteen days during the Christ- 

 mas recess, one of twelve days due to illness on the animal's 

 part , and one of four days during the spring recess. With these 



