LIBRARY

266 COLLEGE ENTOMOLOGY
Suborder HETEROPTERA Latreille 1810
(Het'er-op'ter-a, from the Greek gTfPOS, other, different,
+ rrTEpa, wings; referring to the marked differences between
the fore and hind pairs of wings.) German, Wanzen.
Bugs.
IMPOR.TANT EXTERNAL ANATOMICAL CHARACTER.S
Size - small to very large insects, up to 100 mm. or nearly 4 in.
Shape - slender and sub cylindrical or more commonly rounded, oval, broadly
elongate and flattened, or shield-shaped.
Integument - usually hard and coriaceous or leathery and parchment-like;
pigmented; punctured and rugose, or smooth and shiny; rarely hairy or
spiny.
Color - variable from dull and drab to a great variety of brilliant colors, some
of which are metallic. Some species are varicolored and bizarre.
Head - variable in form and suturation; usually prognathous, but hypognathous
in some forms; generally free and often with a neck-like region.
Compound eyes -large and prominent, many-faceted, widely separated or
small, and absent.
Ocelli - usually present and two in number, rarely absent. Both compound
eyes and ocelli absent in family POL YCTENIDiE.
Antenn:e - usually present and well developed or rarely atrophied or absent;
inserted above or below the eyes; usually four- or five-segmented; segments
simple or ornamented with enlargements; free or fitting into a groove in
the head or prothorax.
Mouth parts - modified for piercing and sucking fluids from plants and
animals. Clypeus - dorsal, small and poorly developed except anteriorly
in the CIMICIDJE and POL YCTENIDJE. Labrum - short, triangular,
slender, and sharply pointed apically Or broad and flap-like; covering bases
of mouth parts. Mandibles - the anterior outer pair of stylets which are
bristle-like and may be serrated apically. Maxill:e - the maxillary,
posterior or inner pair of stylets arising from a basal sclerite or the fused
cardo and stipes; bristle-like and two-grooved along inner margin so as to
form two capillary tubes - a dorsal suction tube and a ventral salivary
ejection tube. Maxillary palpi - vestigial or usually absent. Labium,
rostrum, or proboscis - very small and simple to greatly enlarged into a
short or long, rigid, curved or straight, three- or four-segmented sucking
tube with a dorsal channel enclosing the mandibular and maxillary stylets;
folded between the legs along the venter at rest. Gula - a large chitinized
ventral area behind the base of the labium. Genre -lateral ventral areas
at the sides of the head behind the eyes.
Thorax - compact and closely fused. Prothorax - small or large, sometimes
long and neck-like, and may have lateral prolongations or horns. Meso- and
metathorax - complex, with many sclerites. Scutellum - most important