Class 3. Insecta. Order 1. Orthoptera. 253 



2. Locusts (genus Locusta and others) resemble the previous group in 

 habits, in the stnictiu-e of the wings and hind legs, etc., biit differ in certain other 

 important characters. The antenna are bristle-like, usually very long, and 

 always composed of numerous short joints. On the tibiae of each of the front 

 legs there are two auditory organs (whilst there are none on the abdomen), and 

 the males make sounds by rubbing the basal portion of one elytron, the under- 

 side of which is provided with a ti-ansversely ridged edge, over a corresponding 

 portion of the other. The female possesses a long, sabre-like ovipositor. One 

 of the best known species is the large bright green Locusta viridissima, which, 

 like Locusts in general, devours both animal and vegetable food. Nearly allied to 

 the Locusts are the Crickets [Gryllidas), which agi-ee with them in the pos- 

 session of multiai'ticulate antennae, and in the position of the auditory organs 

 and the vocal apparatvis, but differ iu the shorter hiud legs and the long 

 cerci (the cerci of both Locusts and Grasshoppers are very short), and generally, 

 too, in that the posterior portions of the wings which are folded up, are not 

 covered by the elytra, but project from these as a pair of pointed appendages. 

 Here belong the Cricket (Gryllus domestious), in bake-houses and similar 

 warm places ; and the Field-cricket {O. campestris), common in arid fields, 

 and making passages in the ground ; both vrith well- developed elytra, the female 

 with pro j ectiag ovipositor : f ui-ther the Mole-cricket or Earth-crab 

 {Gryllotalpa vulgaris), whose front legs ai'e developed as enoiinously powerfid 

 digging limbs ; with very large prothorax, short elytra, and no ovipositor ; they 

 lead a subterranean existence, feeding upon plants and animals : all three in 

 Great Britaiu. 



3. Cockroaches (Blatta) ; flattened forms, with long bristle-like antennae, 

 and strong running legs with large femurs; the fore wings ai'e thin elytra, 

 pai-tially overlapping; the abdomen has two anal cerci posteriorly; the head 

 is covered by the anterior edge of the prothorax. Often both pah's of wings, 

 especially in the females, are short or rudimentary. The eggs are laid in 

 chitiL .us capsules, which are carried about for a long time by the female, 

 projecting half out of the genital aperture ; each capsule contains a number of 

 eggs lying in two rows. Two large species of this gi'onp, one of which is the 

 well-known "Black-beetle" {B. \Periplaneia'\ orientalis), have been intro- 

 duced from the tropics into Eui-ope, where they live in houses ; several species 

 occur in the open in England. 



4. The Mantidse are allied to the Cockroaches, but differ in various 

 respects. The body is on the whole more elongate, the prothorax being 

 especially long. The first pan- of legs is prehensile, with large coxs, strong 

 femurs with two rows of spines, and tibisB also furnished with two rows of 

 spines, which can be folded back upon the femurs ; with these appendages the 

 animal seizes its prey, which consists of other Insects. Wings well developed ; 

 in other respects like the Cooki-oaches ; jointed cerci. The ova are attached to 

 plants in groups, sm-rounded, as in Cockroaches, by a capstde formed as a 

 glandular secretion. A large green species of this genus [M. religiosa, the 

 Praying Mantis), occurs in South Etirope. 



5. Earwigs (Forficula), somewhat flattened Insects, which are chiefly 

 characterised by the condition of the wings. The elytra are qxiite short plates, 

 which do not completely cover the thin hind wings, although the latter are much 

 folded. The larger part of the abdomen is left uncovered by the wings; it is 

 strongly chitinised, freely movable, and possesses, posteriorly, a pair of un- 

 jointed cerci, curved to form a pair of pincers. The Eaj-wigs usually remain 

 hidden by day ; they live principally upon vegetable food. The females brood 

 over the eggs. Sevei-al species occur in England. 



6. The Stick- and Leaf-insects {Phasmidx), form a small division 

 of the Orthoptera, including a number of aben-ant species ; they are only 



