FEATHERS OF BIRDS. 573 



feathers, of which this down, serving the purpose 

 of a first garment, hastily spread over the young 

 bird, is but the precursor ; for the tufts generally 

 soon fall off and disappear, except in the rapa- 

 cious tribes, as the eagle and the vulture, where 

 they remain attached to the feathers for a consi- 

 derable time. 



While this temporary protection is given to 

 the integument, extensive preparations are mak- 

 ing underneath for furnishing a more effective 

 raiment, adapted to the future wants of the bird. 

 The apparatus by which the feathers are to be 

 formed is gradually constructing; and its rudi- 

 ments are receiving the necessary supply of 

 nutrient juices, and of vessels for their circula- 

 tion, together with their usual complement of 

 nerves and absorbents. When first visible, this 

 organ has the form of a very minute cone, 

 attached by a filament proceeding from its base 

 to one of the papillae of the skin, and establishing 

 its connexion with the living system. In the 

 course of a few days, this cone has become elon- 

 gated into a cylinder, with a pointed extremity, 

 while its base is united to the skin by a more 

 distinct bond of connexion formed by the en- 

 larged vessels, which are supplying it with nour- 

 ishment. It is in the interior of this cylinder 

 that all the parts of the feather are constructed ; 

 their earliest rudiments being formed at the upper 

 part, or apex of this organ ; and the materials 



