64: 



SEXUAL SELECTION : BIEDS. 



Part II. 



Fig. 42- Outer tail-feather of Scolopax frenata. 



Fig. 43. Outer tail-feather of Scolopax javensis. 



He found that by blowing on these feathers, or by fasten- 

 ing them to a long thin stick and waving them rapidly 

 through the air, he could exactly reproduce the drum- 

 ming noise made by the living bird. Both sexes are 

 furnished with these feathers, but they are generally 



larger in the male than 

 in the female, and emit 

 a deeper note. In some 

 species, as in S. frenata 

 (fig. 42), four feathers, 

 and in S. javensis (fig. 

 43), no less than eight 

 on each side of the tail 

 are greatly modified. Different tones are emitted by 

 the feathers of the different species when waved through 

 the air ; and the Scolopax Wihonii of the United States 

 makes a switching noise wliilst descending rapidly to 

 the earth.^^ 



In the male of the Cliam^ioetes unicolor (a large galli- 

 naceous bird of America) the first primary wing-feather 

 is arched towards the tip and is much more attenuated 

 than in the female. In an allied bird, the Penelope 

 nigra, ]Mr. Salvin observed a male, which, whilst it 

 flew downwards " w ith outstretched wings, gave forth 

 " a kind of crashing, rushing noise," like the falling 

 of a tree.^^ The male alone of one of the Indian 

 bustards (Sypheotides auritus) has its primary wing- 

 feathers greatly acuminated ; and the male of an allied 



'"- See M. Moves" interesting paper in 'Pioc. Zool. Soc' 1858, p. 199. 

 For the habits of the snipe, Macgillivray, 'Hist. British Birds,' vol. iv. 

 p. 871. For the American snipe, Capt. Blakiston, 'Ibis,' vol. v. 1863, 

 p. 131. 



•53 Mr. Salvin, in ' Proe. Zod. Soc.' 1867, p. 160. I am much in- 

 debted to this distinguished ornithologist for sketches of the feathers of 

 the Chamaipetes, and for other information. 



