BIRDS. 429 



the female. In an allied bird, the Penelope nigra, Mr. 

 Salvin observed a male, which, while it flew downward 

 *^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 auritus) 

 has its primary wing-feathers greatly acuHiinated; and the 

 male of an allied species is known to make a humming 

 noise while courting the female, f In a widely different 

 group of birds, namely, humming-birds, the males alone of 

 certain kinds liave either the shafts ^^_ 

 of their primary wing feathers ^H>^ ' ??^ >ito^^''^~' 

 broadly dilated, or the webs ab- 

 ruptly excised toward the extrem- 

 ity. The male, for instance, of 

 Selas2)horus platycercus, when 

 adult, has the first primary wing- Fig. 44 Primary wing-feather 



-,,' / ji\,i "^-T of a humming bird, the /Se/o^- 



feather (fig. 44) thus excised. phorus platycerons (from a 



While flying from flower to flower |t 'tL^ of mkt- ; \SS?r 



he makes *^ a shrill, almost whist- figure, corresponding feather 



ling noise ;";[ but it did not appear ^ emae. 



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 toward 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 (d, e, f) in the 

 female. Even the bones of the wing, which support these 

 singular feathers in the male, are said by Mr. Fraser to be 

 much thickened. These little birds make an extraordinary 

 noise, the first " sharp note being not unlike the crack of a 

 whip." 



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

 indebted to this distinguished ornithologist for sketches of the 

 feathers of the Chamaepetes and for other information. 



f Jerdon, "Birds of India," vol. iii, pp. 618, 621. 



^Qould, "Introd'iction to the Trochilidae," 1861, p. 49. Salvin, 

 " Proc. Zoolog. Soc ," 1867, p. 160. 



i? Sclater, in "Proc. Zool. Soc," 1860, p. 90, and in "Ibis," vol. 

 iv, 1863, p. 175. Also Salvin, in " Ibis," 1860, p. 37. 



