156 THE IMPORTANCE OF BIED LIFE 



can make good such a gap by delicately manipu- 

 lating the separated barbs until the hooks have 

 once more caught. It is thus possible to mend a 

 very ruined-looking quill. 



The external body feathers of a bird, including 

 those of the wing and tail, are as a rule "normal" 

 in character. They produce the quills and downs 

 employed in the upholstery trade. There is a 

 very wide variation between them, however, and 

 some are the reverse of normal. In some species 

 the feathers, where their tips have been exposed 

 to the light and outer air, are waxy at the end as 

 if they had been dipped into colored paraffin. The 

 plumes of the ostrich, bird of paradise, and in- 

 numerable others, lack a sufficiency of hooked 

 barbules to give them firmness and therefore are 

 filmy or downy in character. In the penguin the 

 wing feathers are really bristle-like scales, and in 

 the wingless Apteryx of New Zealand the body 

 feathers resemble hair. And the nuptial plumes 

 of the famous egret are merely delicate shafts 

 with a sparse scattering of long hair-like barbs. 

 The majority of birds, however, have not exceeded 

 the "normal" requirements of nature. 



Aside from these body — or "contour" — and 

 flight feathers, there are two unimportant kinds 

 still to be found on the average bird. The "filo- 

 plumes" arise as a scattering of long hair-like 

 filaments beneath the main body covering. They 

 are the "hairs" which the cook-books demand be 



