450 



REPTILES AND BIRDS. 



ascension by extending their toes, supplied with bent claws, upon the 

 trunk of a tree, and maintain themselves hanging there ; then move 

 themselves a little farther by a sudden and jerked skip, and so on. 

 These movements are facilitated by the disposition of the tail, formed 



Fig. 176. — Ivory-billed Woodpeckers. 



of straight resistant feathers, slightly worn away at their extremities, 

 which, pressed against a tree, serve as a support to the bird. Thanks 

 to this organisation, Woodpeckers traverse trees in every direction — 

 downwards, upwards, or horizontally. Woodpeckers are of a timid 

 and restless disposition ; they live alone in the midst or on the 



