HOEKBILLS 
(Bucerotidw) 
The curious-looking hombills (Malay. Burong^ Knggmg) 
are not only found in the Oriental region, in many parts of 
which they are very familiar birds, bnt members of the family 
are also found in Africa and the Austrahan region. 
In Malaya no less than eleven species are found, some rare 
and denizens of the deep jungk, others common and conspicu- 
ous inhabitants of the trees near human habitations. 
Hombills have always excited attention on the part of 
naturalists for not only is their appearance extremely grotesque, 
but their nesting habits are very strange. The name hornbill 
is of course derived from the large casque which, varying 
greatly in shape in the different species, is situated on the 
upper mandibk. One gets the impression that the bird must 
find its bill rather cumbersome, but this is no doubt not so, for 
with one exception the bill is not sohd but filled with a cellular 
tissue, Hombills are furthermore remarkable in that their 
bones have much larger air spaces than those of most birds aud 
they are also provided with stout eyelashes, rather an unusual 
feature in birds. They are not skilful in the air although 
capable of travelling long distances, and the noise made in fly- 
ing can be heard from afar. This latter fact is no doubt due to 
yet one other peculiar feature in their construction, the noise 
being produced by the rush of air through the open bases of 
the wing-quilis which are not covered by the small feathers 
lining the base of the wing as is usually the case. 
The nesting habits of the hombills are very extraordinary 
for the female is imprisoned in the hollow tree in whicli she 
has laid her eggs, the hole of the nesting cavity being closed 
up with a clay-like substance. Through a small opening in 
this manufactured barrier the male feeds his mate. this 
method seems rather harsh, but perhaps secures immunity' for 
the sitting bird from monkeys and small arboreal carnivorous 
animals. Much more could be related of the very strange 
behaviour of hombills. It could be told how the imprisoned 
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