SCANSORES. 



301 



which being thrown in against the tree acts as a 

 prop. The bird is thus brought to the scene of 

 operations, where, instructed probably by the sense 

 of hearing of the presence of his prey, he has to 

 dig it out. For this purpose, a beak is given him 

 shaped like a wedge, almost as strong and hard as 

 steel, terminating in a fine edge like a chisel. With 

 this efficient instrument, moved by the powerful 

 muscles of the neck, he taps the tree in rapid suc- 

 cession, in an astonishingly short time chisels a 

 hole, and lays bare the insidious grub. But this 

 is not all ; the worm must be extracted, as well as 

 exposed : and here another beautiful piece of mecha- 

 nism is seen. The tongue, by means of a slender 

 elastic bone passing round the back of the head, 

 can be projected far out of the beak : it terminates 

 in a horny point, furnished with little barbs pointing 

 backwards, and is covered moreover with a thick 

 glutinous secretion. 



The species, which are numerous, are scattered 

 over both continents ; six or seven are European, 

 of which one (P. Viridis] is beautifully coloured 

 with green, spotted with white, and marked on the 

 head with red. The most usual colours are glossy 

 black and white arranged in various patterns ; the 

 head, and sometimes other parts, are marked in very 

 many species with vivid crimson or scarlet. 



At the head of the genus may be placed the noble 

 Ivory-billed Woodpecker, (P. Principalis,) so called 

 from the colour and consistence of his polished beak. 

 Wilson says of him, " He may be called the king 



