MIMICR Y OF SED GE- WARBLER 2 1 7 



still calling, though retreating far across the valley. 

 Then I knew that the sedge-bird had deceived me. 

 I then heard it exactly reproduce the twitter of a 

 canary, which, at that time, was hung on a house 

 about fifty yards away ; and then it uttered the 

 most wonderful song I ever heard. It sang a 

 long phrase consisting wholly of alarm-cries, such 

 as one hears when a hawk comes over a numerous 

 population of small birds. The vehement double 

 cries of swallows, the loud cah cah cah of the 

 starling, the cry tourr of the house-sparrow, and its 

 tell tell, with the alarm of the blue tit, were jumbled 

 together as they sometimes are in nature ; and 

 then the sedge-warbler continued his phrase in the 

 single cries of tell in which the old male house- 

 sparrow, watching as a sentinel, warns his neighbour- 

 hood that a hawk is very near. All other cries 

 were abandoned when this signal was reproduced ; 

 and, with lengthening pauses between these notes, 

 the phrase gradually came to a conclusion. The 

 succeeding phrase was of the ordinary kind. On 

 the following day I went to the spot, and saw the 

 singer, a sedge-warbler, in the same bush. 



