IMITATION OF BIRDS 191 



have heard it repeat exactly the pirn im imimim of 

 the blue tit. The hedge-accentor is said to sing some- 

 what like the wren, as it does, but it is as possible 

 that this similarity may have been derived from some 

 persistent source, say, the murmuring of a stream, as 

 that the one bird copied the other. The adherence 

 of this bird to local variations in song can only be 

 accounted for as due to the power of filial mimicry. 

 The Cape broad - billed fly - catcher (Platyrhynchus 

 Capensis) " has a curious harsh, loud, and monotonous 

 note which almost exactly resembles that of the 

 owl Scops Capensis, and is uttered in about the same 

 intervals, four or five times in a minute " (Layard, 

 op. tit. p. 344). The influence of surroundings, 

 in presenting to the notice of birds a restricted 

 range of subjects for imitation, is indicated in their 

 songs. Bechstein wrote of the (wild) red-backed 

 shrike, or butcher-bird (Collurio\ that "it almost 

 exclusively imitates the birds of its immediate 

 neighbourhood," and that in the house its song is 

 composed of the warbling of the birds hung near 

 (op. cit. p. 1 3 7). The resemblance of the song of 

 the scarlet bullfinch (Pyrrhula erythrina) to "some 

 of the notes of the reed-bunting is a remarkable 

 fact. Both these birds live in its immediate neigh- 

 bourhood ): (Naumann, quoted in Bree's Birds of 



