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Encyclopædia Britannica, Ninth Edition/Grasshopper

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GRASSHOPPER (French Sauterelle, Italian Grillo, German Grashüpfer, Heuschrecke, Swedish Gräshoppa), a collective term applied to certain orthopterous insects belong ing to the families Locustidæ and Acrydiidæ, according to the now generally received classificatory views. They are especially remarkable for their saltatory powers, due to the great development of the hind legs, which are much longer than the others and have stout and powerful thighs, and also for their stridulation, which is not always an attribute with them of the male only. The distinctions between the two families may be briefly stated as follows : the Locustidce have very long thread-like antennae, and four- jointed tarsi; the Acrydiidce have short stout antennas, and three-jointed tarsi. As the term "grasshopper" is almost synonymous with Locust, the subject will be more extensively treated under the latter heading (17. v.). Under both "grasshopper" and "locust" are included members of both families above-noticed, but the majority belong to the Acrydiidce in both cases. In Britain the term 13 chiefly applicable to the large green grasshopper (Locusta viridissima) common in most parts of the south of England, and to smaller and more obscure species of the genera Stenobothrus, Gomphoccrus, and Teitix, the latter remarkable for the great extension of the pronotum, which often reaches beyond the extremity of the body. All are vegetable feeders, and, as in all orthopterous insects, have an incomplete metamorphosis, so that their destructive powers are continuous from the moment of emergence from the egg till death. The notorious migratory locust (Pachy- tylus miyratorius) may be considered only an exaggerated grasshopper, and the too-famous Rocky Mountain locust (Caloptetius spretus) is still more entitled to the name. In Britain the species are not of sufficient size, nor of sum cient numerical importance, to do any great damage, and their cheerful " song " more than counteracts the slight mischief they may cause in devouring grasses and other plants. The colours of many of them assimilate greatly to those of their habitats ; the green of the Locusla viridissima is wonderfully similar to that of the herbage amongst which it lives, and those species that frequent more arid spots are protected in the same manner. Yet many species have brilliantly coloured under-wings (though scarcely so in English forms), and during flight are almost as conspicuous as butterflies ; but when settled it is nearly impossible to detect them, even although the spot where they dropped may have been carefully marked ; and they rise again almost under the feet of the observer. Those that belong to the Acrydiidce mostly lay their eggs in more or less cylindrical masses, surrounded by a glutinous secretion, in the ground. Some of the Locustidce also lay their eggs in the ground, but others deposit them in fissures in trees and low plants, in which the female is aided by a long flattened ovipositor, or process at the extremity of the abdomen, whereas in the Acrydiidce there is only an apparatus of valves. The stridulation or " song " is mainly produced by friction of the hind legs against portions of the wings or wing- covers ; but variation exists in the exact method. To a practised ear it is perhaps possible to distinguish the " song " of even closely allied species, and some are said to produce a sound differing by day and night. The British species are not numerous ; but in some parts of the world (and even in Europe) their numbers are very great, both in .species and individuals.