VOCAL AND INSTRUMENTAL MUSIC. 373 



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 Wilsonii of the United 

 States makes a switching noise whilst descending rapidly to the 

 earth.'" 



In the male of the Chamsepetes unicolor (a large gallinaceous 

 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 "with 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 auri- 

 tus) has its primary wing-feathers greatly acuminated; and the 

 male of an allied species is known to make a humming no'ise 

 whilst courting the female.™ In a widely different group of birds, 

 namely Humming-birds, the males alone of certain kinds have 

 either the shafts of their primary wing-feathers broadly dilated, 

 or the webs abruptly excised towards the extremity. The male, 

 for instance, of Selasphorus platycercus, when adult, has the first 

 primary wing-feather (fig. 44), thus excised. Whilst flying from 

 flower to flower, he makes "a shrill, almost whistling noise;"" 

 but it did not appear to Mr. Salvin that the noise was intentionally 

 made. 



Lastly, in several species of a sub-genus of Pipra or Manakin, 

 the males, as described by Mr. Sclater, have their secondary wing- 

 feathers modified in a still more remarkable manner. In the 

 brilliantly-colored P. deliciosa the first three secondaries are 

 thick-stemmed and curved towards the body; in the fourth and 

 fifth (fig. 45, a) the change is greater; and in the sixth and 

 seventh (b, c) the shaft "is thickened to an extraordinary degree, 

 "forming a solid horny lump." The barbs also are greatly 

 changed in shape, in comparison with the corresponding feathers 



=' See M. Meves' interesting: paper in 'Proc. Zool. Soc' 1858, p. 199. 

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

 p. 371. For the American snipe, Capt. Blakiston, 'Ibis,' vol. v. 1863, p. 

 131. 



" Mr. Salvin, in 'Proc. Zool. Soc' 1867, p. 160. I am much indebted 

 to this distinguished ornitliologist for sketches of the featliers of the 

 Cliamaepetes, and for other information. 



== Jerdon, 'Birds of India,' vol. iii. pp. 618, 621. 



™ Gould, 'Introduction to the Trochilidae,' 1861, p. 49. Salvin, 'Proc. 

 Zoolog. Soc' 1867, p. 160. 

 26 



