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THE ESSEX NATURALIST.
Bug, par excellence. So we have three leading ideas conveyed
by the word, viz. : (1) insects in general ; (2) the Hemiptera,
(3) the Bed-bug. It is the second of these to which I invite
your attention this afternoon.
By the Hemiptera, then, we are to understand an Order of
insects, the individual species of which are characterised by the
possession of four flying organs (except in the bed-bug and its
three fellow parasites) antennas with few joints, a sucking mouth,
absence of palpi, and an incomplete metamorphosis.
The Order consists of 2 Sub-orders : (a) Heteroptera, including
the Shield-bugs, Leaf-footed bugs, Stilt-bugs, Leaf-bugs, Damsel-
bugs, Lace-bugs, Bed-bugs, Pond-skaters, Water-scorpions,
Water-boatmen, Giant-Bugs and others ; (b.) Homoptera, in-
cluding Lantern-flies, Cicadas, Frog-hoppers, Tree-hoppers or
Thorn insects, Leaf-hoppers, Plant-lice or Greenflies, Jumping
Plant-lice, White or Snow flies, Scale insects and others.
The unspecified groups in these 2 Sub-orders, not having
attracted popular attention, have not been favoured with ver-
nacular names. The true Lice (i.e., the Sucking Lice), are
comprised in a separate order, Anoplura, chiefly on account
of their unsegmented thorax, sometimes in one piece with
the abdomen.
The principal distinctions between the Sub-orders Hetero-
ptera and Homoptera are that in the latter the antennae are
very short and inconspicuous and the wings entirely mem-
branous, forming a pent-roof over the body at rest, whilst in
the former the antennas are more or less long and always obvious
(except in the section Cryptocerata) and the two front wings,
known as elytra (or hemi-elytra) are thickened and strong,
with flexible membranous tips, except in the Pond-skaters
(Gerris), and lie flat on the dorsal surface of the body with
the membranous tips usually overlapping.
But not all the Heteroptera have fully developed wings and
elytra. In some species the diminution consists in a mere
narrowing of the elytron or a shortening of the membrane only ;
in others both wings and elytra are much reduced in size, some-
times even to mere scales ; in others again the flying organs
are less developed in the female than in the male ; and in yet
other species these organs are entirely absent in one sex or in
both. There are some species also in which fully developed