[Illustration: Fig. 92.--Galgulus Oculatus (Mag.)] _Family 13, Galgulidæ._--This family only includes a few American species, which are generally brown spotted with yellow. _Galgulus oculatus_ inhabits the southern part of the United States, and measures about two-fifths of an inch in length. _Family 14, Nepidæ._--The species of this family are not very numerous, but are of considerable interest. They are of large size, and very fierce and voracious. The genus _Betostoma_, found in the East Indies and America, includes the largest species of _Heteroptera_, some of which measure four and a half inches in length, and nearly six inches in expanse of the wing. Their food consists of small fish, frogs, etc. [Illustration: Fig. 93.--Nepa Cinerea.] The best-known species in our own country is the Water Scorpion (_Nepa cinerea_), which has the power of inflicting a very painful wound if handled. It measures about an inch in length. In colour it is yellowish-grey, the back of the abdomen being red, and its large front legs, which somewhat resemble the claws of a scorpion, have given rise to the name by which it is popularly known. It is very common in stagnant water. [Illustration: Fig. 94.--Notonecta Glauca.] [Illustration: Fig. 95.--Metacanthus Punctipe (Mag.)] _Family 15, Notonectidæ._--These insects are commonly known as "Water Boatmen," from their habit of rowing themselves about on their backs with their long hind legs. They are carnivorous, feeding on small insects and other "fry." The most typical British species is _Notonecta glauca_, a yellowish insect about half an inch long. It is a most predaceous insect, and can bite severely. Another common species inhabiting our own country is _Coriax Geoffroyi_, which is nearly half an inch long. The _Notonectidæ_ are all very powerful and active creatures. [Illustration: Fig. 96.--Corisa Striata.] SUB-ORDER II.--HOMOPTERA. This extensive sub-order includes the Cicadas, Lantern Flies, Plant Lice, Scale Insects, etc. [Illustration: Fig. 97.--Fulogra Horsfieldi.] As already pointed out, the most striking general character of this group consists in the uniform texture of the forewings. [Illustration: Fig. 98.--Cixius Cunicularius (Mag.)] There are eleven families included in the _Homoptera_, all the species belonging to which feed upon vegetable juices. _Family 1, Cicadidæ._--These insects are mostly inhabitants of warm climates, and our only British representative of the family (_C. anglica_) is one of the smaller species, the wings only expanding about an inch and a quarter. Four or five hundred species, however, are known to inhabit the world, and some of them attain to considerable dimensions. [Illustration: Fig. 99.--Delphax Longipennis.] [Illustration: Fig. 100.--Derbe Strigipennis (Mag.)] They generally live upon trees and shrubs, and obtain their nourishment by piercing the tissues and sucking out the juices of their young tender shoots.