72 W. T. SHEPHERD 



indications of forming the association ; in thirty trials 6 it responded 

 to A-3, the food-note, fourteen times, and to A-l two times. 

 Its first correct reaction was in the eleventh trial, the next in the 

 twelfth, next the fourteenth, then the seventeenth, and in an 

 increasing degree throughout that day's tests. On the second 

 day, in fifteen trials, or in forty-five trials in all, Pet had per- 

 fected the association. In fifteen trials on that day it responded 

 to A-3 fourteen times with one doubtful response, and to A-l 

 one time with three doubtful. In two trials that day, the fourth 

 and the seventh, the animal got up at A-l, but got down at once 

 and appeared, from its looks and actions to know that it had 

 made a mistake. In ten test trials four days later, the cat 

 reacted to A-3 ten times and to A-l none. 



Mary.— The older animal showed no definite indication of 

 forming the association until the third day. On that day, in 

 ten trials, it responded to A-3 eight times and to A-l five times 

 with two doubtful responses. After this, Mary continued to 

 improve, and on the seventh day had perfected the association. 

 In twenty trials that day, or in ninety trials in all, the animal 

 responded to A-3 nineteen times, and to A-l, five times, with two 

 doubtful. At the twentieth trial, when I sounded A-l, Mary 

 went to "washing her feet," and appeared, by her actions, to 

 know that no food was to be gotten at that note. In two ad- 

 ditional day's tests, Mary responded to A-3 twenty times in 

 twenty trials each day, with five and four wrong responses res- 

 pectively on the eighth and ninth days. This cat never entirely 

 inhibited the tendency to react to A-l. 



2. Discrimination of a Difference of One Octave of Pitch. 

 Notes A-2 and A-l on a Harmonica. Fed at A-2. 



Pet. — In the first day's experiment, in ten trials, the animal 

 gave no positive response. I had handled it rather roughly on 

 the previous day, and the cat appeared uneasy and afraid of 

 me. Also it did not seem hungry. On the following day, in 

 twenty trials, or in thirty trials in all, Pet reacted to A-2 eighteen 

 times and to A-l two times. It did not respond to A-2 in the 

 first trial nor in the eleventh. The animal reacted to A-l 

 (wrong) in the third and fifth trials only. When it got up at 

 A-l in the fifth trial, it got down at once, and gave every indication 

 6 That is in thirty trials of each auditory stimulus. 



