368 The Descent of Man. Part II, 



Vocal and instrumental music, — With birds the voice serves to 

 express various emotions, such as distress, fear, anger, triumph, 

 or mere happiness. It is apparently sometimes used to excite 

 terror, as in the case of the hissing noise made by some nestling- 

 birds. Audubon 25 relates that a night-heron (Ardta nycticorax, 

 Linn.) which he kept tame, used to hide itself when a cat 

 approached, and then " suddenly start up uttering one of the 

 " most frightful cries, apparently enjoying the cat's alarm and 

 " flight." The common domestic cock clucks to the hen, and 

 the hen to her chickens, when a dainty morsel is found. The 

 hen, when she has laid an egg, " repeats the same note very often, 

 " and concludes with the sixth above, which she holds for a 

 longer time ; " 26 and thus she expresses her joy. Some social 

 birds apparently call to each other for aid ; and as they flit from 

 tree to tree, the flock is kept together by chirp answering chirp. 

 During the nocturnal migrations of geese and other water-fowl, 

 sonorous clangs from the van may be heard in the darkness 

 overhead, answered by clangs in tne rear. Certain cries serve 

 as danger signals, which, as the sportsman knows to his cost, 

 are understood by the same species and by others. The 

 domestic cock crows, and the humming-bird chirps, in triumph 

 over a defeated rival. The true song, however, of most birds 

 and various strange cries are chiefly uttered during the breed- 

 ing-season, and serve as a charm, or merely as a call-note, to the 

 other sex. 



Naturalists are much divided with respect to the object of the 

 singing of birds. Few more careful observers ever lived than 

 Montagu, and he maintained that the " malos of song-birds and 

 " of many others do not in general search for the female, but, 

 " on the contrary, their business in the spring is to perch on some 

 K conspicuous spot, breathing out their full and amorous notes, 

 " which, by instinct, the female knows, and repairs to the spot to 

 " choose her mate." 27 Mr. Jenner Weir informs me that this 

 is certainly the case with the nightingale. Bechstein, who kept 

 birds during his whole life, asserts, " that the female canary 

 " always chooses the best singer, and that in a state of nature 

 " the female finch selects that male out of a hundred whose 

 " notes please her most." 28 Thero can be no doubt that birds 

 closely attend to each other's song. Mr. Weir has told me oi 



25 ' Ornithological Biograph.' A-ol. vogel,' 184-0, s. 4. Mr. Harrison 

 v. p. 601. Weir likewise writes to me: — "I 



26 The Hon. Daines Barrington, "am informed that the best singing 

 ' Philosoph. Transact.' 1773, p. 252. " males generally get a mate first, 



27 ' Ornithological Dictionary,' " when they are bred in the same 

 1833, p. 475. « room."" 



2? ' Natursreschichte del Stubea- 



V 



