so BIRD BEHAVIOUR 



between the small Magpie-sized Hornbills of the 

 genus Tochus, with little or no " top-story " to the 

 bill, to the large typical Hornbills, often as big- as 

 hen Turkeys, with enormous bills generallyj crowned' 

 with a great homy excrescence. The smaller kinds- 

 are more insectivorous than the larger, and thus' 

 show some approach to the Wood^-Hbopocs (Irtiser), 

 which have much more curved bills than the ordinary 

 Hoopoes, and'feed when on trees, while the common 

 Hoopoes are ground-feeders. 



It has been well i suggested that the great bills of' 

 the larger Hornbills and Toucans are adapted' to 

 giving a purchase for wrenching off tough-stalked 

 fruit ; as the birds grew bigger, too, they would' 

 not be able to venture on such slender branches, 

 and so would need more to reach out for their food: 

 And if- the beak had got merely longer ■wjithout 

 acquiring bulk, any wrenching effort vrould have- 

 been liable to dislocate it; That Hornbills at any 

 rate work their beaks^ very hard may be inferred- 

 from the facts that: in the largest and bulkiest-beaked > 

 kinds the edges of the jaws are worn and chipped' 

 in elderly specimens, and that if the fruit will 

 not come away by fair means, some Hornbills think 

 nothing of throwing- themselves bodily off- the 

 bough and wrenching it away by sheer weight. No 

 doubt the effort of recovering their perch in 

 gymnastic exercises like this is what gives these 

 particularly awkward-looking birds the deftness- on 

 the wing which many people must have observed 

 when watching them catch in the air grapes or other 



