COURTSHIP. 97 



formed, having a stiff, sabre-shaped shaft with the 

 oblique barbs of unusual length, the outer webs 

 being strongly bound together. He found that by 

 blowing on these feathers, or by fastening them 

 to a long thin stick and waving them rapidly 

 through the air, he could reproduce the drumming 

 noise made by the living bird. . . ." In some 

 species four feathers and in others no less than 

 eight on each side of the tail are greatly modified. 

 The variation in the number and shape of these 

 feathers give rise to a corresponding variation in 

 the tone of the sound produced. 



The guan, a South American game-bird, pro- 

 duces a similar sound with its wings. The late Mr 

 Salvin says of it, " I well remember being startled 

 by a strange sound when shooting in one of the 

 ravines in the Volcan de Aqua in Guatemala. 

 Not at first perceiving whence it arose, I walked 

 on, when the noise was again repeated. I then 

 set about discovering the cause and soon found 

 that it was produced by a male Fenelopina nigra 

 (the black penelope) which, when flying in a 

 downward direction with outstretched wings, 

 gave forth a kind of crashing, rushing noise, 

 which I likened at the time to the falling of a 

 tree." 



The manakins — small perching birds of South 

 America — have the shafts of the secondaries, or 

 quill-feathers of the forearm curiously "thickened 

 to an extraordinary degree, forming a solid, horny 

 lump." . . . These little birds make' an extra- 

 ordinary noise, the lirst " sharp note being not 

 unlike the crack of a whip." 



A very remarkable form of drumming is 

 G 



