EXPERIMENTS ON THE RABBIT 169 



in all. Unfortunately we had reached a period where the young 

 rabbits no longer responded satisfactorily to the tests, whether 

 this was due to the arrival of hot weather or to some other 

 cause. Abednego developed in the course of the seiies many 

 right-hand and left-hand tendencies. Finally he formed an 

 elaborate habit, which consisted in going to the right end of the 

 box, strolling completely around the box, coming back to the 

 front, and pushing the left-hand door. Sometimes he would 

 turn back on his course before getting all the way around, and 

 then he would push the right-hand door, again the first one he 

 encountered. This habit was broken up by putting the box in 

 a corner of the room, but the rabbit seemed to have lost interest 

 in doors and in the box as a whole, so that we felt little confidence 

 in the results. There were, however, six successive days on which 

 no place tendency appeared, and on these the total percentage 

 of choices of the blue was 63, the percentages of the several 

 days being 50, 70, 70, 80, 60, and 66. There is therefore some 

 indication that blue can be discriminated from grey number 2, 

 either as a color or because it looks darker than the grey. 



D. Experiments with Shadrach {male) 



Series 27. Red and Hering grey number 7. Red opens. This 

 series was made during the same period as Series 20, and under 

 the conditions described in the report of that series. 



In the 33 tests performed at the rate of three a day, the rabbits 

 being tested in rotation, Shadrach made a total of 67 per cent. 

 right choices. 



In the 44 tests made at the rate of four a day, Shadrach made 

 a total of 61 per cent, of right choices. 



In the 40 tests made at the rate of four a day, the tests on 

 one rabbit being completed before those on another were begun, 

 Shadrach made a total of 67 per cent, of right choices. 



No experiments were made on this rabbit from April 16 to 

 May 8. On May 9 and 10 he was given 20 tests, 10 a day, with 

 red and gray number 7, and chose the red every time. 



Series 28. Saturated blue and Stoelting black paper. Black 

 opens. This series corresponds to Series 23. Ten experiments 

 were made a day, with the exception of one day on which only 

 six were made. In the 56 tests, Shadrach chose the black 91 



