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"blooded bird clotlied in featbers is very considerable. It is one, 

 moreover, that existed apparently at a remote period, for it is 

 known that the most ancient bird of which we have any actual 

 record was distinguished from its reptilian contemporaries in a 

 similar manner, as the impressions of true feathers occur associated 

 with its remains. Some external characters, however, are 

 common to both classes. Scales defend the naked legs of many 

 birds, and the terminal claws of the extremities are often attached 

 to the wings as well as to the feet, as in the spur-winged goose, 

 the lapwings, the jacanas, and the chakar or crested screamer of 

 South America, which Kitchen Parker considered to be the 

 nearest living ally to the fossil Archaeopteryx, and as half rail, 

 half goose. But the plumose covering clothing the greater portion 

 of the bird's body, and the source of much of its attractive beauty, 

 is peculiarly appropriate to the life that the creature leads, sub- 

 jected to great variations of temperature. It is also more com- 

 plicated in structm-e and grovvth than all modifications of the 

 epidermic system. The plumage of birds influences the contour 

 of their bodies and their capacity for sustained flight, and in a 

 measure regulates their way of life. The shape of the quill 

 feathers of the wing diffeis much in the various flying birds. 

 They are acuminate m the swiftn, or so short and rounded in the 

 gallinaceous birds as to enable them to fly only short distances 

 " with an exertion and vibratory noise well known to every sports- 

 man."* In the haivks and owls a loose soft plumage, permitting 

 them a noiseless flight, assists in the capture of their prey. 



All feathers, notwithstanding great differences in size, 

 consistence, and colour, are composed of the same elements, a 

 quill or barb supporting the shaft, whence a beard or vane 

 diverges on either side. They resemble allied structures such as 

 hair, bristles, and spines, all termed dermatophytes, or skin plants 

 by Nitzsch, as being produced by the skin and rooted therein. 

 But the hair-producing organ is always present and active, while 

 the feather capsule is in a state of alternate activity and repose. 

 Of the four principal kinds of feathers present in the generality 

 of birds, the chief are the contour feathers exposed to the surface, 

 and the inner or down feathers which underlie them. The 

 surface feathers are rufliedby a series of complex muscles, as many 

 as 12,000 being developed in one species {Anas viarila) for that 

 purpose, a remarkable instance of the development of specialised 



*Mr. Charles Dixon in his " Migration of Birds " shows these characteristics 

 to be functional resultants, the birds that migrate the farthest having the 

 Songest and most slender wings. 



