A few are brilliantly colored, and many are grotesque in shape. 
They are closely related to members of the order Hemiptera, but 
are distinguished by their uniformly-textured wings and by the 
point of origin of the beak at the back of the underside of the 
head. The mouth parts consist of four piercing stylets (the man- 
dibes and maxillae). Many species are wingless, at least in the 
female sex under certain conditions. Where wings are present, 
they are usually four in number with the front pair longer and 
the hind pair often wider. The wings do not overlap much at the 
tip, and their bases are never abruptly thicker than their tips. 
They usually stand sloping roof-shaped over the abdomen while 
the insect is at rest. Members of many families are able to conceal 
themselves beneath various protective coverings such as froth, 
waxy tufts, hard waxy shells, and the sloughing epidermis of 
bark. The majority are also able to produce honeydew. 
Homopterous insects differ greatly in their biologies; some 
species produce several generations per year while others may 
require several years to complete one life cycle. The life history 
of some species is also very complex, involving both bisexual and 
parthenogenetic generations, winged and wingless individuals 
and generations, and sometimes the regular alteration of food 
plants. However, all species are phytophagous, and they feed on 
an almost endless variety of plants of all sizes and ages. They 
feed by inserting their beaks into plant tissues and extracting the 
sap. A large number of species are injurious both to cultivated 
crops and to forest, shade, and ornamental trees. 
FAMILY FLATIDAE 
FLATID PLANTHOPPERS | 
A number of species of flatid planthoppers feed on trees and 
shrubs, but they are seldom of economic importance. Members of 
different genera differ greatly in body and form. Those occurring 
in this country are usually less than 12 mm. in length, and many 
have the head greatly modified, with the part in front of the eyes 
greatly enlarged and snoutlike. A useful characteristic for recog- 
nizing them is the position and form of the antennae. The two 
basal segments are stout, whereas the remainder consist of a 
nearly pear-shaped basal segment and a segmented, bristle-like 
terminal part. They also have a few large spines on the hind tibiae. 
Two fairly common species are Anormenis septentrionalis (Spin.) 
and Metcalfa pruinosa (Say). The nymphs, which feed on the 
undersurfaces and midribs of leaves, resemble small masses of 
cotton, and are about 6 mm. in diameter. They jump when dis- 
turbed. Osborn (574) and Van Duzee (731) discuss the group. 
FAMILY CICADELLIDAE 
THE LEAFHOPPERS 
This is one of the largest families of insects in the world; all 
appear to be plant feeders. The adults range in length from about 
3 to 15 mm., and come in an almost endless variety of colors. 
Certain species resemble flatid planthoppers but they differ in hav- 
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