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EARWIG
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EARWIG , an See also:insect belonging to the Forficulidae, a See also:family usually referred to the See also:Orthoptera, but sometimes regarded as typifying a See also:special See also:order, to which the names Dermaptera, Dermatoptera and Euplexoptera have been given, in allusion to certain peculiarities in the structure of the wings in the See also:species that possess them. The front wings are See also:short and horny and when at See also:rest meet without overlapping in the See also:middle See also:line, like the wing-cases of brachelytrous (cocktail) beetles. The See also:hind wings, on the contrary, are for the most See also:part membranous and, when extended, of large See also:size; each consists of two portions, the distal of which, in virtue of the arrangement and jointing of its nervures, is capable of being both doubled up and folded fanwise beneath the proximal, which is partly horny when the wing is tucked away under the front wing-See also:case of the same See also:side. Apart from these characteristics, the most distinctive feature of earwigs is the presence at the end of the See also:abdomen of a pair of pincers which are in reality modified appendages, known as cercopods, and represent the similar limbs of Japyx and the caudal feelers of See also:Campodea and some other See also:insects. The Forficulidae are almost See also:cosmopolitan; but the various species and genera differ from each other both in structure and size to a comparatively slight extent. The length and See also:armature of the pincers and the presence or See also:absence of wings are perhaps the most important features used by systematists in distinguishing the various kinds. Of particular zoological See also:interest in this connexion is a Ceylonese genus Dyscritina, in which the cercopods are See also:long, many-jointed and filiform during the See also:early stages of growth, and only assume at the last See also:moult the forcipate structure characteristic of the family. The best known earwig is the See also:common See also:European species, Forficula auricularia. This insect is gregarious and nocturnal. It hides by See also:day under stones or From Strasburger's Lehrbuch der Bolanik, by permission of Gustav See also:Fischer. GeasterGranulosus, nat. size. the loosened bark of trees or in any crevice or hole sheltered from the See also:light. At See also:night it crawls about in See also:search of See also:food, which consists to a small extent of dead See also:animal or See also:vegetable See also:matter, but principally, as gardeners are aware, of the petals and other parts of See also:flowers of growing shoots and soft ripe See also:fruit. During the See also:winter earwigs See also:lie dormant; but in the early months of the See also:year See also:females with their eggs may be found in the See also:soil, frequently in deserted See also:earthworm burrows. Maternal instincts are well See also:developed, both the eggs, which number about fifty, and the See also:young being carefully brooded and watched over by the See also:parent. Except for the absence of wings, the young are See also:miniature See also:models of the adult. As growth proceeds the integument is periodically See also:cast; and at the final moult the perfect winged insect appears. See also:Males and females are like each other in size, but may be distinguished by the difference in the number of visible abdominal segments, the male having nine and the See also:female seven. In the male, moreover, the pincers are caliper-like and toothed at the See also:base, whereas in the female they are untoothed and only lightly curved at the tip. These See also:differences suggest that the pincers aid in the pairing of the sexes. However that may be, they are known to be used in the folding of the wings; and their importance as weapons of See also:defence is attested by the precision and effect with which they are wielded against assailants like ants. (R. I. Additional information and CommentsThere are no comments yet for this article.
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