INARTICULATE SOUNDS IN THE PARROT 



363 



speak in response to similar sounds. Believing that this result 

 could be repeated easily, I made no records at this time. Later 

 I was unable to get any response at all when the bird could not 

 see me. However, in view of the fact that the bird was hardly 

 familiar with the piano, not at all with the violin or cello, and 

 had learned to sing by hearing the human voice only, the lack 

 of control experiments does not seem to invalidate the results. 



EXPERIMENT 2. TIMBRE 



With the purpose of bringing out a somewhat wider range 

 of sounds the following experiment was undertaken. Whistling, 

 coughing, smacking of the lips, whispering and guttural speech 

 were used as stimuli, repeated in irregular order. The results 

 were : — 



Stimulus Times given 



Guttural speech 10 



Whistling 10 



Whispering 10 



Cough 10 



Smacking of lips 5 



Response Times given 



Guttural muttering. . . 10 



Whistling 10 



Whispering 10 



Cough 10 



A similar sound 4 \ 



Whispering 1 / 



Control experiments are again lacking but I did succeed in 

 obtaining the responses while my hand was so held that the 

 bird could not see the movements of my lips in making the 

 sounds. The results of this and the preceding experiment seem 

 to furnish sufficient evidence that the responses were given upon 

 the basis of sound and that the bird is able to distinguish clangs 

 and musical tones through the range of pitch and timbre em- 

 ployed. He does not reproduce the timbre of the sounds with 

 absolute accuracy (there is no difference between his responses 

 to the piano, violin and voice) and, while this is probably due 

 to the limitations of his vocal apparatus, it makes it somewhat 

 more difficult to state with certainty that the responses are 

 imitative. The reproduction of pitch offers a more conclusive 

 test of this, since it is less likely to have been learned by any 

 chance system of reward or punishment. 



EXPERIMENT 3. PITCH 



The bird's singing register is about one octave extending 

 upward from C 2B8 . Notes within this interval were sounded 



