Chap. XIII. Birds. 359 



with each other. They charm the female by vocal or instru- 

 mental music of the most varied kinds. They are ornamented 

 by all sorts of combs, wattles, protuberances, horns, air-distended 

 sacks, top-knots, naked shafts, plumes and lengthened feathers 

 gracefully springing from all parts of the body. The beak and 

 naked skin about the head, and the feathers are often gorgeously 

 coloured. The males sometimes pay their court by dancing, or 

 by fantastic antics performed either on the ground or in the air. 

 In one instance, at least, the male emits a musky odour, which 

 we may suppose serves to charm or excite the female; for that 

 excellent observer, Mr. Kamsay, 1 says of the Australian musk- 

 duck (Biziura lob da) that " the smell which the male emits 

 " during the summer months is confined to that sex, and in 

 " some individuals is retained throughout the year; I have 

 " never, even in the breeding-season, shot a female which had 

 " any smell of musk." So powerful is this odour during the 

 pairing-season, that it can be detected long before the bird can 

 be seen. 2 On the whole, birds appear to be the most aesthetic of 

 all animals, excepting of course man, and they have nearly the 

 same taste for the beautiful as we have. This is shewn by our 

 enjoyment of the singing of birds, and by our women, both 

 civilised and savage, decking their heads with borrowed plumes, 

 and using gems which are hardly more brilliantly coloured than 

 the naked skin and wattles of certain birds. In man, however, 

 when cultivated, the sense of beauty is manifestly a far more 

 complex feeling, and is associated with various intellectual 

 ideas. 



Before treating of the sexual characters with which we are 

 here more particularly concerned, I may just allude to certain 

 differences between the sexes which apparently depend on 

 differences in their habits of life; for such cases, though 

 common in the lower, are rare in the higher classes. Two 

 humming-birds belonging to the genus Eustephanus, which 

 inhabit the island of Juan Fernandez, were long thought to be 

 specifically distinct, but are now known, as Mr. Gould informs 

 me, to be the male and female of the same species, and they 

 differ slightly in the form of the beak/* In another genus of 

 humming-birds (Grypus), the beak of the male is serrated along 

 the margin and hooked at the extremity, thus differing much 

 from that of the female. In the Neomorpha of New Zealand, 

 there is, as we have seen, a still wider difference in the form of 

 the beak in relation to the manner of feeding of the two sexes. 

 Something of the same kind has been observed with the gold- 



1 < Ibis,' vol. iii. (new series) 1867, 2 Gould, ' Handbook to the Birds 



p. 414. cf Australia,' 1805, vol. iL.p. 383. 



