SONGS OF BIRDS. 203 



seen especially in male humming-birds. Sometimes, how- 

 ever, both sexes are equally ornamented, and in rare cases 

 the female is more highly colored than the male; she is 

 sometimes also larger, as in most birds of prey. There is 

 little doubt that the bright colors of male birds render 

 them more conspicuous and to be more readily chosen by 

 the females as mates, for in birds, as in higher animals, the 

 female may show a preference for or antipathy against cer- 

 tain males. Indeed, as Darwin remarks, whenever the sexes 

 of birds difier in beauty, in the power of singing, or in pro- 

 ducing what he calls "instrumental music," it is almost 

 invariably the male which excels the female. 



The songs of birds are doubtless in part love-notes, 

 though birds also sing for pleasure. The notes of birds 

 express their emotions of joy or alarm, and in some cases 

 at least the calls of birds seem to convey intelligence of the 

 discovery of food to their young or their mates.* They 

 have an ear for music; some species, as the mocking-bird, 

 will imitate the notes of other birds. The songs of birds 

 can be set to music. Mr. X. Clark has published in the 

 American Naturalist (vol. xiii. p. 21) the songs of a num- 

 ber of our birds. The singular antics, dances, mid-air evo- 

 lutions, struts, and posturings of different birds, are with- 

 out doubt the visible signs of emotions which in other birds 

 find vent in vocal music. 



The nesting habits of birds are varied. Many birds, as 



* "It is necessiirjr in a philosoplncal spirit to regaid every sound 

 made by a bird under the all-powerful Influence of love or lust as a 

 ' song.' It seems impossible to draw any but an arbitrary line between 

 the deep booming of tlie emeu, the harsh cry of the guillemot (whicli 

 when proceeding from a hundred or a thousand throats strikes the 

 distant ear in a confused murmur like the roar of a tumultuous crowd), 

 the plaintive wail of the plover, the melodious whistle of the wid- 

 geon, the 'cock's shrill clarion,' the scream of the eagle, the hoot 

 of the owl, the so'ema chime of the bell-bird, the whip-cracking of 

 the manakin, the chaffinch's joj'ous burst, or the hoarse croak of the 

 raven, on the one band, and the bleating of the snipe or the drum' 

 ming of the ruffed grouse ou the other." (A. Newton.) 



