LIBRARY

HEMIPTERA 267
division of the mesonotum, often very large and may even cover the abdomen.
Metanotum - reduced or well developed.
Legs - variable and adapted for crawling, walking, jumping, grasping prey,
and swimming. Femora - frequently greatly enlarged; smooth or spined.
Tibil£ - cylindrical or flattened, plain, swollen, or with leaf-like enlargements,
and with swimming hairs in aquatic forms; often hairy or
spined, but usually without apical spurs. Tarsi - normally three-segmented,
rarely one- or two-segmented and heteromerous; sometimes
greatly reduced. Claws - apical or ante-apical with or without arolia or
empodia.
Wings - adults may be wholly apterous, brachypterous, or have rudimen·
tary wings; two pairs, usually folded flat over the dorsum with the apical
portions overlapping; fore wings or hemelytra with basal portions thickened
or coriaceous and divided into two areas: the clavus and corium (from the
corium may also be separated the narrow embolium and the wedge-shaped
cuneus) and with the apices membranous, hind wings wholly membranous;
veins distinct, obscure, and often few or almost entirely wanting. In some
species (TINGIDlE) the membranous areas are indistinct and in others
(ENICOCEPHALIDlE) the wings are wholly membranous.
Spiracles-two pairs, one each on the meso- and metathorax.
Abdomen - usually rather wide, but long and slender in some groups; nineto
ll-segmented, usually lO-segmented.
Spiracles - usually a pair on each of the first seven or eight abdominal segments;
most often on the ventral sides.
Ovipositor - well developed in the aquatic families NEPIDJE and NOTO­
NECTIDJE and such terrestrial families as LYGJEIDJE, some ANTHQ­
CORID.t'E, and others.
Sound-produdng organs -
1. Prostemal cross-striated furrow scraped by rough apex of the rostrum
in REDUVIIDtE and PHYMATIDtE.
2. Lateral strigose areas on abdominal segments IV and V rubbed by extensions
on the inner sides of hind tibice.
3. Tarsal and femoral dentic1es contacted in a right to left manner and
vice versa.
4. Coxal rasps functioning against similar areaS on the margins of the
coxal cavities in the genus Ranatra.
5. File at base of abdomen contacting comb on venter of wing bases in
certain species of Tessaratoma.
IMPORTANT INTERNAL ANATOMICAL CHARACTERS
Tentorium - absent (present in HOMOPTERA)
Digestive System.
Alimentary canal - complex.
Mouth - no true mouth: entrance to the digestive tract through suction
canal at base of sty lets and pharyngeal duct.