[Illustration: After Weed, Riley and Howard, _Insect Life_, vol iii.
FIG. 11.--Cabbage Aphid (_Aphisbrassicae_). a, Male; c, female (wingless). Magnified. b and d, Head and feelers of male and female, more highly magnified.]
[Illustration: After Howard, _Year Book U.S. Dept. Agr._, 1894.
FIG. 12.--Apple Scale Insect (_Mytilaspis pomorum_). a, Male; e, female; c, larva magnified--; b, foot of male; d, feeler of larva, more highly magnified.]
The _Cicadidae_ are for the most part large insects with ample wings; they are distinguished from other Homoptera by the front thighs being thickened and toothed beneath. The broad head carries, in addition to the prominent compound eyes, three simple eyes (ocelli) on the crown, while the feeler consists of a stout basal segment, followed by five slender segments. The female, by means of her serrated ovipositor, lays her eggs in slits cut in the twigs of plants. The young have simple feelers and stout fore-legs (fig. 10) adapted for digging; they live underground and feed on the roots of plants. In the case of a North American species it is known that this larval life lasts for seventeen years. The "song" of the male cicads is notorious and the structures by which it is produced have already been described (see also CICADA). There are about 900 known species, but the family is mostly confined to warm countries; only a single cicad is found in England, and that is restricted to the south.
The _Fulgoridae_ and _Membracidae_ are two allied families most of whose members are also natives of hot regions. The _Fulgoridae_ have the head with two ocelli and three-segmented feelers; frequently as in the tropical "lantern-flies" (q.v.) the head is prolonged into a conspicuous bladder, or trunk-like process. The _Membracidae_ are remarkable on account of the backward prolongation of the pronotum into a process or hood-like structure which may extend far behind the tail-end of the abdomen. Two other allied families, the _Cercopidae_ and _Jassidae_, are more numerously represented in our islands. The young of many of these insects are green and soft-skinned, protecting themselves by the well-known frothy secretion that is called "cuckoo-spit."