April 11, 1902.] 



SCIENCE, 



591 



the reasonable conclusiou that ''two birds, 

 isolated from their own kind and from all 

 hirds, but with a strong inherited tendency to 

 sing, originated a novel method of song, and 

 that four birds, isolated from wild representa- 

 tives of their own kind and associated with 

 these two, who had invented the new song, 

 learned it from them and never sang in any 

 other way." This piece of work seemed to show 

 such carefulness in experiment, in observation, 

 and in the conclusion drawn, as to deserve the 

 highest commendation, and it raised the hope 

 of good work to follow. 



But this hope was not fully realized in the 

 sequel. The second article is devoted to cases 

 of birds having acquired new notes in various 

 ways. Some of the statements in this paper 

 are of value, but some show a very insecure 

 foundation. For example, Mr. Scott quotes 

 from Miss Emily B. Pellet, in Bird Lore, 

 what he considers a 'well-attested case 'of talk- 

 ing in a wild rose-breasted grosbeak. But 

 a critical examination of Miss Pellet's article 

 leads inevitably to the conclusion that the 

 grosbeak was not talking at all, it was simply 

 giving bird notes, and imagination put into 

 them the likeness to human speech. This is 

 indicated by the clear, musical character of 

 the notes, by the peculiar non-human accentua- 

 tion, and by the fact that the words were not 

 repeated in parrot-fashion, but were freely 

 rearranged in different sentences. Even if 

 it were proved that the bird talked, it would 

 be utterly unreasonable to conclude that 

 it had learned to talk while a wild bird; 

 the natural supposition would be that it 

 had learned in captivity and had then 

 escaped. The over-credulity of Mr. Scott 

 in this case leads us to doubt the other 

 examples he cites from unknown observers — 

 those of the whistling and talking of canaries, 

 and that of a duck imitating the call of a tur- 

 key. It is most important to know how close 

 is the imitation in each case, for there is no 

 subject on which popular evidence is so worth- 

 less as on the subject of mimicry. The crudest 

 resemblance in appearance or in sound may be 

 exaggerated into a case of 'perfect' imitation. 

 We can find as much as we choose of this sort 

 of evidence of mimicry. 



As to Mr. Scott's own observations, there is 

 one statement to be criticized, and that is 

 that some birds reproduced the direction of a 

 sound. What can this mean? It shows that 

 Mr. Scott is not familiar with the psychologic 

 basis of ventriloquism, or he would know that 

 the ventriloquist can not indicate direction by 

 his voice, but only by using some means to 

 attract the attention of the listener to the 

 desired point. And as for birds, it is highly 

 improbable that they ever attempt to indicate 

 the direction of a sound. Direction may be 

 suggested by purely extraneous causes, and an 

 example of this kind fell under my notice last 

 spring which so well illustrates the point that 

 I think it worth giving. I was standing on 

 the top of a bluff overlooking a river-bottom; 

 trees grew thickly in the bottom-land and up 

 the bluff till just over my head. I heard the 

 song of a robin, now loud and strong and ap- 

 parently almost overhead ; then very faint, and 

 coming, as it seemed, from the tops "of the 

 trees in the bottom-land. From the robin's 

 habit of singing a loud strain and a faint one 

 alternately, it seemed probable that there was 

 only one songster in this ease, but it was 

 almost impossible, at times, to avoid feeling 

 that there were two birds, one almost over- 

 head, and the other below my position^ in the 

 tops of the trees by the river. By changing 

 my position I was able to see the bird, and to 

 see that the same bird sang both songs. It 

 was on a branch which overhung the bluff, 

 being between the two positions from which 

 the sound had seemed to come. In singing 

 lovidly, it had seemed nearer to me than, it 

 really was. Now, if it had been nearer, it 

 would necessarily have been in the branches 

 which were more directly overhead, and there- 

 fore I seemed to hear the sound coming down 

 from those branches. But when the song 

 sounded far away, it seemed too far to come 

 from the trees of the bluff, and therefore I 

 was forced to think that it came up from those 

 of the bottom-land below. The case of Mr. 

 Scott's birds is undoubtedly explicable in some 

 similar way. The birds imitated only the 

 sound itself, and the faintness of the sound, 

 or the faintness combined with other quali- 

 ties of the sound, was associated in his mind 



