COURTSHIP AMONG BIRDS 109 



former runs along the ground uttering a resonant " too-u 

 tooo-u " repeated seven or eight times in rapid succession, 

 all the while he approaches nearer to the apparently very 

 much-otherwise-engaged female. This effort failing, he 

 will then often rise on quivering wings twenty or thirty 

 feet into the air, and dive gracefully down again imme- 

 diately afterwards, deflating this curious balloon to await 

 a more favourable opportunity. 



In some species where wind-bags are employed as 

 aphrodisiacs the outer skin is brilliantly coloured and 

 exposed during the display. The Prairie-hen affords a 

 case in point. In this species the air-chamber is fur- 

 nished, not by the gullet, but by the air-sacs of the neck. 

 When these are inflated they appear as two large orange- 

 coloured bodies standing boldly out among the feathers. 

 Their effect is heightened by a tuft of long stiff feathers 

 which are thrust forward like a pair of horns, on each 

 side of the head, while at the same time the feathers of 

 the back are set on end, the tail is spread like a great 

 fan, and the wings are half opened and trailed like those 

 of the Turkey. 



The displays take place in the early hours of the morning, 

 when parties of from a dozen to fifty, of both sexes, meet 

 on some slight knolls where the grass is short. Having 

 duly assembled, the more ardent cocks immediately begin 

 to prepare for the morning revels, the first part of the 

 performance apparently being of a comparatively passive 

 nature — the parade of the air-sacs and the erection of 

 the feathers. 



Then some " proud cock, in order to complete his 

 triumph, will rush forward at his best speed . . . through 

 the midst of the love-sick damsels, pouring out as he 

 goes a booming noise . . . which may be heard for at 



