290 BIRD BEHAVIOUR 



(Geopelia humeralis) has one note exactly like that 

 of the common Cuckoo. 



Cuckoos themselves are just as remarkable for 

 curious notes as for parasitism and for resemblances 

 in appearance to birds of alien families ; thus 

 we have the well-known " Brain- fever- bird " of 

 India {Hierococcyx vatius), with its strange tri- 

 syllabic notes running up the scale, and preceded 

 by an overture, while the dissyllabic note of the 

 Koel {Eudynamis honorata) also runs up the scale. 

 Our own Cuckoo's note is known to be so truly 

 musical that it can be imitated easily by mechanical 

 means and even struck on the piano, and as every 

 one knows is so readily rendered by the human 

 voice that " early Cuckoos " are always regarded 

 with grave suspicion. 



Nightjars also have many strange notes, the 

 machine-like whirring of our familiar species being 

 rivalled by the singular sound produced by a 

 common Indian species (Caprtmulgus indicus), which 

 is ju^t like the sound of a stone bounced along ice; 

 and the human-sounding notes of the American 

 " Whip-poor-will " (Caprtmulgus vociferus) have 

 long been celebrated. 



Other mammalian voices besides man's come in 

 for this fortuitous imitation ; the roar of the cock 

 Ostrich is not unlike that of the lion, and the 

 American Cat-bird {Galeoscoptes carolinensis), which 

 is a Mocking-Thrush, and the Australian Cat-bird 

 i/Elurcedus viridis), one of the Bower-birds, have 

 obtained their names from their cat-caUs, while 



