THE CLASS BIRDS. 



325 



thick, arched above, or conical, and generally straight (Fig. 

 309). The pelicans present a remarkable modification of the 

 bill; between the two branches of the lower jaw there is a 



Fig. 305. The Griffon Vulture. 

 (Vultur fulvus). 



Fig. 306. Pouched Crane, or 

 Adjutant-bird. 



wide cutaneous expansion or bag, in which they store their 

 food (fishes), to disgorge it afterwards, and to feed on it at 

 their leisure. 



Fig. 307. Bee-Catcher; 

 Merops. 



Fig. 308. Goat-sucker. 

 (Caprhnulgus.) 



But some birds present singularities in the form of the bill, 

 the uses of which are not understood. Such for example is 

 the bill of the rhinoceros hornbill, or calao (Fig. 312). 



