Organs of Nutrition 



125 



such extension of tongue as the deep burrows of the 

 ants necessitate in the case of the Flicker. 



Thus the tongue of a bird seems a very unstable 

 character, acted upon quickly and radically by any 

 change in the diet of the species. The entire tip of the 

 tongue is frequently frayed out into a kind of brush, 



remarkably developed in 

 the parrot-like lories. Yet 

 this curious structure is 

 probably only an elonga- 

 tion of the papillae, hom- 

 ologous with those which 

 make the tongue of a cat 

 or lion so rough. Cocka- 

 toos, although first cousins 

 to the lories, have very 

 different tongues, thick and 

 flesh}' with club-shaped 

 tips. 



In our common gold- 

 finch, the sides of the 

 tongue curl inward, form- 

 ing an admirable seed- 

 scoop, while the same or- 

 gan in the chickadee, being distinctly cleft into sev- 

 eral prongs at the tip, has been likened to a ''four- 

 tined pitchfork" on which its little owner impales the 

 myriad grubs and insects for which it so industriously 

 searches twigs and leaves. The great particoloured bill 

 of a toucan conceals a very curious tongue — a long 



Fig. 97. — Thick fleshy tongue of Cockatoo 



