140. PECKHAM. [Vol. 1, 



these facts, we find the scale-formed plumes of the throat, the 

 crests of the head, and the long cirrhi of the tail, all fully devel- 

 oped before the plumes which spring from the side of the body 

 begin to make their appearance. If, on the other hand, the 

 male paradise birds have not acquired their distinctive plum- 

 age by successive variations, but liave been as they are now 

 from the moment they first appeared on the earth, this succes- 

 sion becomes at least unintelligible to us, for we can see no 

 reason why the changes should not take place simultaneously, 

 or in a reverse order to that in which they actually occur."* 



27(6 Ornamental Plumes of the Gallinacea^. are not Confined to the 

 Area of the Most Powerful Muscles. 



To answer Mr. Wallace's argument from the gallinacete it 

 should be necessary only to present a number of cases of 

 running birds with sexual colors and plumes which are found 

 on other parts of the body than the area of the muscles which 

 move the hind limbs and elevate the tail. The proposition 

 being that where there is great muscular activity there is surplus 

 vitality, which is disposed of in the formation of ornamental 

 plumage, we must show that ornamental plumage frequently 

 arises from parts of the body which have no especial muscular 

 activity. 



We have such a case in the Argus Pheasant, which is as 

 highly decorated as the peacock and is as truly a gallinaceous 

 bird, but which has its chief ornament in a different place. 

 The two elongated tail-feathers are insignificant when compared 

 with the enormous expanse and exquisite marking of the wings, 

 the unwieldy size of which almost deprives the male bird of 

 flight. In "The Geographical Distribution of Animals" Mr. 

 Wallace, in speaking of this bird, says : " It is interesting to 

 note, that during the display of the plumage the bird's head is 

 concealed bj' the wings from a spectator in front, and, contrary 

 to what usually obtains among pheasants, the head is entirely 

 unadorned, having neither crest nor a particle of A'ivid color, — 



' Malay AwhipelnKo. p. .'So9. 



