92 SEXUAL SELECTION: BIRDS. [Part II. 



ited ; but tlic ])ir(l " when excited often spreads them out 

 hiterally, " so that they can be seen even from above." " 

 The common j>igeon has iridescent featliers on the breast, 

 and every one must have seen how the male inflates his 

 breast while courting the female, thus showing off these 

 feathers to the best advantage. One of the beautiful 

 bronze-winged pigeons of Australia ( Ocyphaps lophotes) 

 behaves, as described to me by Mr. Weir, very differently : 

 the male, Avhile standing before the female, lowers his head 

 almost to the ground, spreads out and raises perpendicu- 

 larly his tail, and half expands his wings. He then alter- 

 nately and slowly raises and depresses his body, so that 

 the iridescent metallic feathers are all seen at once, and 

 glitter in the sun. 



Sufticient facts have now been given to show with 

 what care male birds display their various charms, and 

 this they do with the utmost skill. While preening their 

 feathers, they have frequent opportunities for admiring 

 themselves, and of studying how best to exhibit their 

 beauty. But as all the males of the same species display 

 themselves in exactly tlie same manner, it appears that 

 actions, at first perhaps intentional, have become instinc- 

 tive. If so, we ought not to accuse birds of conscious 

 vanity ; yet when we see a peacock strutting about, with 

 exj^anded and quivering tail-feathers, he seems the very 

 emblem of pride and vanity. 



The various ornaments possessed by the males are cer- 

 tainly of the highest importance to them, for they have 

 been acquired in some cases at the expense of greatly-im- 

 peded powers of flight or of running. The African night- 

 jar i^Cosmetornis), which during the pairing-season has 

 one of its primary wing-feathers developed into a streamer 

 of extreme length, is thus much retarded in its flight, !»1- 

 though at other times remarkable for its swiftness. Tlie 



" ' Birds of India,' vol. ii. p. 96. 



