BUGS. 
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beaks. Although the domestic kinds above mentioned are 
without wing-covers ' and wings, yet most bugs have both, 
and, with the former, belong to an order called Hemiptera, 
literally half-wings, on account of the peculiar construction 
of their wing-covers, the hinder half of which is thin and 
filmy like the wings, while the fore part is thick and opaque. 
There are, however, other insects provided with the same 
kind of beak, but having the wing-covers sometimes entirely 
transparent, and sometimes more or less opaque, and these, 
by most entomologists, are also classed among Hemipte- 
rous insects, because they come much nearer to them than 
to any other insects, in structure and habits. Bugs, like 
other insects, undergo three changes, but they retain nearly 
the same form in all their stages ; for the only transformation 
to which they are subject, from the young to the adult state, 
is occasioned by the gradual development of their wing-covers 
and wings, and the growth of their bodies, which make it 
necessary for them repeatedly to throw off their skins, to 
allow of their increase in size. Young, half-grown, and 
mature, all live in the same way, and all are equally active. 
The young come forth from the egg without wing-covers 
and wings, which begin to appear in the form of little scales 
on the top of their backs as they grow older, and increase 
in size with each successive moulting of the skin, till they 
are fully developed in the full-grown insect. 
The Hemiptera are divided into two groups, distinguished 
by the following characters. 
1. Bugs, or True Hemiptera, ( Hemiptera hcteivptera,') in 
which the wing-covers are thick and opaque at the base, but 
thin and more or less transparent and wing-like at the tips, 
are laid horizontally on the top of the back, and cross each 
other obliquely at the end, so that the thin part of one wing- 
cover overlaps the same part of the other ; the wings are also 
horizontal, and are not plaited ; the head is more or less hori- 
zontal, and the beak issues from the fore part of it, and is 
abruptly bent backwards beneath the under side of the head 
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