Class II. GREEN WOODPECKER. 241 



they are provided with a long flender tongue, 

 armed with a fharp bony end barbed on each 

 fide, which by the means of a curious apparatus of 

 mufcles * they can exert at pleafure, darting it to 

 a great length into the clifts of the bark, transfix- 

 ing and drawing out the infedls that lurk there. 



They make their nefts in the hollows of trees: in Nest. 

 order therefore to force their way to thofe cavities, 

 their bills are formed ftrong, very hard, and 

 wedge-like at the end -, Dr. Berham obferves, that 

 a neat ridge runs along the top, as if an artift had 

 defigned it for flrength and beauty. Yet it has 

 not power to penetrate a found tree : their per- 

 foration of any tree is a warning to the owner to 

 throw it down. 



Their legs are (hort, but ftrong •, their thighs 

 very mufcular : their toes difpofed, two backwards, 

 two forward : the feathers of the tail are very ftifF, 

 fliarp pointed and bending downwards. The three 

 firft circumftances do admirably concur to enable 

 them to run up and down the fides of trees with 

 great fecurity ; and the ftrength of the tail fupports 

 them firmly when they continue long in one place, 

 either where they find plenty of food, or while they 

 are forming an accefs to the interior part of the 

 timber. This form of the tail makes their flight 

 very awkward, as it inclines their. body down, and 

 forces them to fly with fliort and frequent jerks 



* PbiL Tranf, Martin's ahridg, V. p. 55. plate 2. 



when 



