Bugs, Cicadas, Aphids, and Scale-insects 207 
sharp stylets or lancets (maxillse and mandibles) to lacerate the plant-tissues, 
and then the pharyngeal pump sucks up from the wound the flowing sap. 
When too many pumps are drawing away too much sap, the leaves wilt, 
yellow, and die. When too many leaves wilt, the plant starves to death. 
And if the leaves happen to be the corn-leaves, and the pumpers chinch- 
bugs, we have the result estimated for us (by the official U. S. statistician) in 
millions of dollars of loss, as in 1887, when this particular loss in the Missis¬ 
sippi Valley states was $60,000,000. 
The eleven plant-feeding families of true bugs (Heteroptera) can be 
distinguished by the following key: 
Antennae 4-segmented. 
Fore wings reticulated and of uniform thin substance throughout. Tingitid^e. 
Fore wings of various forms or absent, but not reticulated, and not of uniform thin 
substance throughout. 
Beak 3-segmented; body greatly flattened. Aradid^e. 
Beak 4-segmented; body not greatly flattened. 
* Membrane (apical area) of fore wings with one or two closed cells at base, but 
otherwise without veins (Fig. 268).Capsid^e. 
Membrane of fore wings with four or five simple or anastomosing longitudinal 
veins arising from the base; or with a larger number of veins arising from 
a cross-vein at the base. 
Ocelli wanting; membrane of fore wings with two large cells at the base, and 
from these arise branching veins (Fig. 268).Pyrrhocorid^e. 
Ocelli present. 
Head with a transverse incision in front of the ocelli. Berytid^e. 
Head without transverse incision. 
Membrane of fore wings with four or five simple veins arising from the 
base of the membrane; the two inner ones sometimes joined to a 
cell near the base (Fig. 268). Lyg.eid.e. 
Membrane of fore wings with many usually forked veins springing from 
a transverse basal vein (Fig. 268). Coreid,e. 
Antennae 5-segmented. 
Scutellum nearly flat, narrowed behind. 
Tibiae unarmed or furnished with very fine short spines. Pentatomid^e. 
Tibiae armed with strong spines in rows. Cydnid^e. 
Scutellum very convex and covering nearly the whole of the abdomen. 
Small, black (sometimes with bluish or greenish tinge). Corimel^nid^:. 
Not black... Scutellerid^e. 
The first of the families in the above table, the Tingitidae, includes the 
curious small lace-bugs (Fig. 287), readily recognized by the delicate gauze- 
or lace-like appearance of the back, due to the uniform thin and reticulated 
character of the fore wings and of the wing-like expansions of the prothorax. 
About twenty-five species are found in this country, all being plant-feeders, 
living mostly on shrubs and trees. Hawthorn-bushes and oak-, sycamore-, 
and butternut-trees all have particular species of lace-bugs on them. In the 
