STRAIGHT-WINGED INSECTS 
291 
Photo by P. 
Dando^ F.Z.S. 
EARWIG 
The forcepi^ 
like append- 
age at the end 
of this insect' s 
body is said to 
be used for 
folding and 
unfolding the 
wings 
STRAIGHT-WINGED INSECTS, OR EARWIGS, COCKROACHES, SOOTHSAYERS, 
STICK-INSECTS, CRICKETS, GRASSHOPPERS, AND LOCUSTS 
BY W. F. KIRBY, F.L.S. 
The insects of this order are less numerous in species than those of any other but the next, 
and are easily recognised. The fore wings are usually of a leathery consistency, and the hind 
wings are folded beneath them like a fan in the more typical families, though in 
the Earwigs and Cockroaches a somewhat different arrangement prevails. In the 
Earwigs, indeed, the wings are doubled back at the ends, and in the Cockroaches 
the wing-cases, or “ tegmina,” as they are technically called, overlap. As a rule 
these insects feed entirely on vegetable substances. The “ Soothsayers” form an 
exception, being carnivorous, though they are not parasitic, like the Ichneumon- 
flies, but feed on fresh food ; and several species of Earwigs, Cockroaches, and 
Crickets, especially those which are semi-domesticated, are omnivorous, and will 
eat animal as well as vegetable food. These insects have an imperfect metamor- 
phosis ^ — that is, there is no inactive pupa-state; but the young, on emerging from 
the egg, already possess a recognisable resemblance to their full-grown parents, 
and their metamorphosis consists of a series of moults, before the last of which 
rudimentary wings appear in those species which ultimately acquire these appen- 
dages. A considerable number of species never have wings, a circumstance which 
frequently renders it difficult to determine whether a specimen is fully developed. 
The antennae are usually long, and the joints distinctly separated, but are very rarely feathered. 
At the other end of the body we often find two long jointed organs, called “ cerci.” The jaws 
are always furnished with strong mandibles. Many Grasshoppers and Locusts have a curious 
arrangement on the shank of the front leg, consisting either of a round or an oval cavity 
on each side, closed by a membrane, or of two long parallel slits in front. These are con- 
sidered to be organs of hearing. The largest known insects belong to this order; the proportion 
of large or moderate-sized species is considerable; and the smallest are probably considerably 
larger than the smallest members of any other group. They are not numerous in temperate 
climates ; there are only about fifty British 
species, and most of the larger of these are 
either naturalised species, or merely casual 
visitors from abroad. 
The Earwigs form the first family. Some 
are wingless, but most have very short wing-cases, 
under which very large wings, forming the most 
beautiful feature of these otherwise unattractive 
insects, are doubled and folded into a very 
small compass. Some of the smaller species fly 
readily ; but others, such as the COMMON Ear- 
wig, though furnished with ample wings, are 
rarely seen to use them. The most conspicuous 
organ of the earwigs is the curious forceps at 
the extremity of the body, the use of which 
does not seem to be well made out, though it 
has been suggested that it is used for folding 
and unfolding the wings. The forceps differs 
very much in size and shape in different species ; 
it is always larger in the male than in the 
female, and often differently shaped. In the 
common earwig the male forceps is flattened 
and contiguous at the base, and rounded and 
Pholt hy IV. P. Dando, F.Z.S. 
AMERICAN 
COCKROACH 
Common in many warehouses and now found in most parts of the 
world 
