[Illustration: FIG. 74.--A Pentatomid (_Stiretrus anchoraga_).]
[Illustration: FIG. 75.--The Blood-sucking Cone-nose (_Conorhinus
sanguisuga_). _a_, mature bug; _b_, pupa.]
For the most part the directions for collecting Coleoptera will apply to
this order of insects equally well, especially so far as concerns the
first section of the order (Heteroptera), and the higher families of the
second section (Homoptera). A few directions may be given for the lower
forms, including the Aphididae, Coccidae, Aleurodidae, and Psyllidae, and
the suborder Parasita, including the degraded forms which infest man and
the lower animals. The Plant-lice or Aphides should always be collected
in connection with their food-plants, and it is very essential also to
collect the same species at different seasons of the year to obtain the
different forms or generations, which frequently present very marked
differences. It is also very necessary to secure the winged forms, which
are usually produced toward autumn, and without which the species are
not easily identified. The Bark lice or Scale-insects should also be
collected in connection with the leaves or twigs which they infest. The
males of these insects are minute and, as a rule, two-winged, resembling
small gnats, and may be bred from the male scales. The females are for
the most part stationary, being fixed to the plant by the protecting,
waxy, excretion or scale. The Flea-lice (_Psyllidae_) frequently produce
galls, and these should always be collected with the insect architects.
Some species do not produce galls, and may be collected by sweeping. The
Hackberry is infested by large numbers of species of Psyllids, and these
produce a great variety of interesting galls. The Aleurodidae
(Fringe-scales) are delicate insects, and easily injured in the
taking; they are therefore best reared from their stationary and
fringed larvae and pupae, which occur on the leaves of many plants. Leaves
bearing the latter should also be collected and pinned or preserved in
alcohol. The Parasita, the lowest representatives of the order, may be
obtained from the domestic and wild animals which they infest.
[Illustration: FIG. 76.--The Bed-bug (_Acanthia lectularia_). _a_,
young; _b_, adult--enlarged.]
[Illustration: FIG. 77.--The Short-nosed Ox-louse (_Haematopinus
eurysternus_). _a_, female; _b_, rostrum; _c_, ventral surface, last
segments of male; _d_, female; _e_, egg; _f_, surface of egg greatly
enlarged.]