BIRDS. 427 



" the head appears to he in two places at once." The sound 

 thus produced is audible at a considerable distance, but 

 cannot be described; and I feel sure that its source would 

 never be conjectured by any one hearing it for the first 

 time. As this jarring sound is made chiefly during the 

 breeding-season, it has been considered as a love-song; but 

 it is perhaps more strictly a love-call. The female, when 

 driven from her nest, has been observed thus to call her 

 mate, who answered in the same manner and scon appeared. 

 Lastly, the male hoopoe ( Upupa epops) combines vocal 

 and instrumental music; for during the breeding-season 

 this bird, as Mr. Swinhoe observed, first draws in air and 

 then taps the end of its beak perpendicularly down against 

 a stone or the trunk of a tree, "' when the breath being 

 forced down the tubular bill produces the correct sound." 

 If the beak is not thus struck against some object the 

 sound is quite different. Air is at the same time swallowed 

 and the oesophagus thus becomes much swollen; arfcfthis 

 probably acts as a resonator, not only with the hoopoe but 

 with pigeons and other birds.* 



In the foregoing cases sounds are made by the aid of 

 structures already present and otherwise necessary; but in 

 the following cases certain feathers have been specially 

 modified for the express purpose of producing sounds. 

 The drumming, bleating, neighing or thundering noise (as 

 expressed by different observers) made by the common 

 snipe (Scolopax gallinago) must have surprised every one 

 who has ever heard it. This bird, during the pairing- 

 season, flies to "perhaps a thousand feet in height/' and 

 after zig-zagging about for a time descends to the earth in 



* For the foregoing facts see, on birds of paradise, " Brebm, 

 ' Tliierlebtn," Band iii, s. 325. On grouse, Kichardson, "Fauna 

 Bor. Aineric.: Birds," pp. 343, 359; JVJaj. W. Ross King, "The 

 Sportsman in Canada," 1866, p. 15(>; Mr. Haymond, in Prof. Cox's 

 "Geoi. Survey of Indiana," p. 227; Andubon. "American Ornith- 

 olog. Biograpn.," vol. i, p. 216. On the Kalij pheasant, Jerdon, 

 " Birds of India," vol. iii, p. 533. On the weavers, "Livingstone's 

 Expedition to the Zambesi," 1865, p. 425. On woodpeckers, Mac- 

 gjllivray. " Hist, of British Birds." vol. iii, 1840, pp. 84, 88. 9, 

 95. On. tbe hoopoe, Mr. Sxvinhoe, in " Proc. Zoolog. Soc.," June 3, 

 1863, 1871, p. 348. On the night-jar, Audtibon. ibid, vol. 

 ii. p. 255, and "American Naturalist," 1878, p. 672. The English 

 night-jar likewise makes in the spring a curious noise during its 

 rapid Eight. 



