242 



THE FOOD OF ANIMALS 



such as young corn and turnips, clover and plantains, but it 

 includes berries and seeds, insects and their larvae, molluscs, 

 myriapods, frogs, or even small reptiles and mammals." 



HORNBILLS 



The remarkable Hornbills (see vol. i, p. 164), native to the 

 warmer parts of Africa, Asia, and Australia, are reserved as the 

 last example of omnivorous flying birds, because they present 

 a marked exception to the very general rule that a mixed diet is 



Fig. 460.— Skull of Hombill [Bttceros galeaius), in section 



associated with what may be called average structural characters. 

 Here, however, we find an enormous beak, suggesting adaptation 

 to a peculiar diet. This organ is not, however, so heavy as it 

 looks, being largely made up of loose spongy bone (fig. 460). 

 The food usually consists of various fruits, roots, insects, and 

 other invertebrates, together with small backboned animals. As 

 a general rule these varied articles of diet are first thrown up in 

 the air, then caught and swallowed whole, the animal part of the 

 food being killed as a preliminary. In explanation of the curious 

 beak it may be remarked that in birds this organ is often used 

 as a defensive weapon, and this appears to be the case in Horn- 

 bills, especially in the female, as will be explained elsewhere. 



