IvANGUAGK OI^ BIRDS 



corded a case of a blackbird that used to utter the 

 words " Pretty Polly" quite distinctly from a 

 tall tree near his bed-room window in Regent's 

 Park. He believed that unless the utterance of 

 those words were a mere fluke the bird may have 

 picked them up from a neighbouring parrot, for, 

 he adds, the blackbird is at times imitative, though 

 not nearly so much so as the starling, the sedge- 

 warbler, or even the song-thrush. 



Those who are fond of endeavouring to trace 

 the " utility " of any unusual trait exhibited by 

 wild creatures may be interested in dealing with 

 this curious trick of mimicry. Although for the 

 most part, we may take it, it comes merely from 

 a natural delight in repeating sounds that are 

 impressive, there are cases where it seems to be 

 adopted with an ulterior motive. Audubon, the 

 great American ornithologist, states that the 

 Northern shrike imitates the cries of a bird in 

 distress in order that it may lure others of the 

 same species within striking distance, and the 

 same habit has been attributed to our own great 

 grey shrike. Mr. Frank Finn, in his valuable 

 work " Bird Behaviour" calls attention to the 

 fact that an Indian shrike, that preys on frogs, 

 has a way of incorporating the screams of the 

 hapless batrachians in its song, and he argues that 

 other shrikes might easily begin imitating the 

 cries of distressed birds merely for amusement, 

 and then develop the habit for profit as well as 

 pastime. 



D1A1.ECT IN Birds' Song. 



Most observers are aware that the songs of 

 birds of the same species differ considerably even 

 in a single locality. Thus a thrush or a skylark 

 may often be noted that exceeds all other in the 

 neighbourhood in the power and variety of its 

 notes. In the Hartz mountains where the 



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