[Illustration: FIG. 82.--A blind Cricket (_Hadenalcus_) from Mammoth
Cave. (From Packard.)]
The insects of this order may all be collected by the use of the
sweeping net. Some of the families are attracted to light, as certain of
the roaches and green locusts, or Katydids (_Locustidae_). Our common
roaches (_Blattidae_) are cosmopolitan insects, and infest dwellings.
Certain species are also found about ponds, under rotten logs, the bark
of trees, and particularly in decaying vegetable matter. In the tropics
the species are very abundant, but aside from the domestic forms, they
occur rarely in northern latitudes. The collection of the egg-cases
(ootheca) is important as they furnish many interesting characters. The
Mantidae, of which the Preying Mantis (_Phasmomantis carolina_) is a
type, are sluggish, carnivorous insects frequently found about houses
and may best be collected by general sweeping of vegetation. The
Phasmidae or Walking-sticks are herbivorous and may be collected in the
midst of vegetation by sweeping or by the hand. The crickets
(_Gryllidae_) frequent, for the most part, moist situations. Certain
forms, like the Mole-cricket and the Jumping Water-crickets
(_Trydactylus_ spp.), burrow in moist soil and occur in numbers near the
edges of ponds and water courses. The katydids and locusts are abundant
on low shrubs or trees and in pasture and meadow land, but are most
numerous in the somewhat dry, arid regions of the West. Most of these
insects mature in late summer and fall and should be collected at this
season. The Forficulidae or Earwigs are very odd-looking insects,
resembling somewhat the Rove-beetles (_Staphylinidae_), and are provided
with a prominent anal forceps. They are very rare in the United States,
are nocturnal in habit; and, flying about at dusk, may be attracted to
light or may be secured by sweeping after nightfall. They feed on
flowers and fruit.