74 W. T. SHEPHERD 



In the third trial (the first correct response), in the eighth and 

 in the fifteenth, though giving the correct response to the stimulus, 

 the cat's reactions were slow, as if in some doubt what to do. 

 On the second day, in twenty trials, or forty trials in all, Pet reacted 

 to the louder noise twenty times and to the lesser noise none. 

 In the second and fourth trials it started to respond to the lesser 

 noise but stopped. On the next day, being tested in fifteen trials, 

 the animal made no mistakes. 



We may regard the results of these experiments as positive. 

 In the experiments on pitch discrimination, the criticism may be 

 offered that the experimenter should have sounded the notes 

 out of the animal's sight. This is true, but as I had no assistant, 

 it was not practicable. However, I was careful not to give the 

 cats any cue to the correct response, by any difference of attitude 

 when the food notes were sounded and when the other notes 

 were played. So it does not seem possible to attribute the 

 reactions of the animals to anything else than the association of 

 a certain note with food-getting, and the consequent discrimina- 

 tion of that note from the other notes. Moreover, several 

 observed incidents in the course of the experiments, such as 

 getting up at the wrong note and getting down at once, strengthen 

 this conclusion. Furthermore, the looks and actions of the ani- 

 mals, to an unbiassed observer, would indicate such clear discrimi- 

 nation of the notes. We conclude, therefore, that eats, or at 

 least some cats, discriminate musical pitch, and also discriminate 

 noises of different degrees of intensity. 



It will be noted that in the experiment in which two individuals 

 were tested, i.e., in the discrimination of a difference of two octaves 

 of pitch on a harmonica, while the younger animal formed the 

 association in 45 trials, the older animal required 90 trials to 

 perfect the association. Again, as compared with the ability 

 of raccoons, in similar tests, of the discrimination of the difference 

 of two octaves of pitch on a harmonica, while the cats took 

 respectively 45 and 90 trials, the two raccoons tested required 

 100 and 150 trials respectively to form the association. In 

 exactly similar experiments which the writer made on two Rhesus 

 monkeys, one individual formed the association in 30 trials, and 

 the other in 40. Though, from the fewness of the individuals 

 used in these different experiments, we are not warranted in 

 drawing final conclusions as to the comparative rapidity of the 



