Descriptive List of the Common Birds 
tail. The beak is nearly a foot in length, and 
is rendered more conspicuous than it would 
otherwise be by a structure known as a casque. 
This is a horny excrescence nearly as large 
as the bill, which causes the bird to look as 
though it were wearing a hat, which it had 
placed for a joke on its beak rather than its 
head. The eye is red, and the upper lid is 
fringed with eyelashes which add still further 
to the oddity of the bird’s appearance.” 
The nesting habits of these birds are curious. 
They nestle in holes in trees. When the eggs 
are laid the hen goes into the hole, the en- 
trance to which is plastered up by the cock 
and hen until the orifice is only just large 
enough to allow of the insertion of the beak. 
Thus the hen remains a voluntary prisoner 
until the young are ready to leave the nest, the 
cock bringing food to her. 
The great majority of hornbills are confined 
to the large forests, and so cannot be called 
common birds. ‘T'wo of the smaller species, 
however, are more widely distributed. (Illus. 
F. III., p. 140.) 
121. Lophoceros birostris: The Common 
Grey Hornbill. (F. 1062), (J. 144), (IV, but 
with the tail a foot long.) 
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