120 RELATION OF SONG TO THE TERRITORY 



or at least a large majority of them, have, in 

 greater or lesser variety, cries and calls which 

 are peculiar to certain seasons and certain 

 situations ; and since on many occasions we 

 have indisputable evidence of the utility of 

 the sound produced — as when, upon the alarm 

 being given by one individual, the flock of 

 Lapwing rises, or when, in response to a 

 particular note of the parent, the nesthng 

 Blackcap ceases to call — so are we bound to 

 infer that aU the cries are, in one way or 

 another, serviceable in furthering the life of 

 the individual. 



But besides these caU-notes, birds produce 

 special sounds during the season of reproduc- 

 tion — some by instrument, others by voice, 

 others again by the aid of mechanical device. 

 And not only is this the case, but many 

 accompany their songs with pecuUar flights, 

 such as soaring to a great height, or circling, 

 or floating in the air upon outstretched wings. 

 These special sounds and special flights are 

 those Avith which I now propose to deal 

 including under the heading "song" all sounds 

 whether harsh c/r monotonous or beautiful, and 

 whether vocally or otherwise produced ; and I 

 shall endeavour to show not only that they are 

 related to the "territory," but that they con- 

 tribute not a little to the successful attainment 

 of reproduction. 



The vocal productions are infinite in variety 

 and combination. At the one extreme we 

 have songs composed of a single note repeated 



