LIBRARY

CHAPTER VIII
6. Order ORTHOPTERA Olivier 1789 1
(Or-thop'ter-a, from Greek ope6s, straight, + 7rTEpa, wings.)
Locusts, Grasshoppers, Katydids, Crickets, Mole Crickets.
Medium-sized to large insects, usually with a pair of narrow leathery fore wings or
tegmina and a pair of well-developed membranous hind wings which fold longitudinally
and are covered by the tegmina when at rest. Many are brachypterous or apterous.
They have strong biting mouth parts; compound eyes; usually two or three ocelli or
none; short or long, simple or segmented cerci j and simple metamorphosis.
This very important and destructive order numbers about 12,000 species,
distributed generally throughout the entire world with the exception of the
polar regions. The members are peculiar in that the vast majority of species
are saltatorial and have the hind legs developed for jumping. Certain species
on every continent migrate in immense hordes and devastate great areas of
native and cultivated plants. Since the dawn of civilization locusts have harassed
every human race, destroying crops and causing suffering and death by
famine. For this reason they appear among the earliest records of antiquity.
They are for the most part ground-living insects, a number being subterranean
and many arboreal. Their food is almost wholly vegetation, which they
consume in quantities. A very few forms are partly or wholly predacious on
other insects and other animals of like size, while even the vegetarian types become
cannibalistic in the absence of normal food. Certain species of crickets and
grouse locusts live near water and swim readily and even dive, but lhe average
orthopteran that ventures into the water is soon destroyed by fishes, as every
country boy knows.
Palreontologically the members of this order may be traced through certain
related ancestors back to the carboniferous period.
External anatomy. - Structurally these orthopterans are peculiarly different
from all other insects. Yet it is possible to point out certain characteristics only
by specimens or by illustrations. The adults are decidedly elongated and more
or less cylindrical in form although many are compressed, others depressed, and
still others quite robust. The exoskeleton is tough and leathery and often protected
by the folded tegmina and wings. The sutures separating the many body
parts are of considerable value in classification. The head is set into the prothorax;
the face is vertical and the mouth ventral. The antennre are often conspicuously
long, filiform, and many-segmented, the compound eyes large and
1 The name ORTHOPTERA was first applied to this group and related forms by Olivier in
1789 and more appropriately reslricted in its use by l.atreille in 1796 who later also designated
them as SALTATORIA in 1817. For years it was a loosely interpreted group which only recently
has been restricted to more homogeneous forms.
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