1902 Encyclopedia > Hemiptera

Hemiptera




HEMIPTERA (hemi [Gk.], half, and pteron [Gk.], wing), an order of the Insecia most commonly known by the name of " bugs," and containing the species so well known to infest houses. In their earlier stages they have what is known amongst naturalists as an incomplete metamorphosis; that is to say, after quitting the egg, and during the two stages of their existence before assuming the perfect form, they move freely about, thus unlike the Lepidoptera, ifec, whose pupa state, or that preceding the perfection of the insect, is quiescent. When the transformations have been completed, the insect generally possesses four wings. The superior pair, or hemielytra as they are called by authors, are attached to the mesothorax, and are composed of two substances,—the basal portion coriaceous, or resembling leather, and the apical one membranaceous, or resembling thin, transparent parchment. The lower pair are attached to the metathorax, and are entirely membranous and generally transparent, and capable of being folded when the insect is in repose. This segment of the sternum likewise bears on each side, anteriorly, a more or less reniform-shaped orifice, within which lies a sac containing the fluid or matter from which so many of the Heteropterous portion of the order emit a most disagreeable odour. They also possess in all stages a mouth (rostrum) composed of three or more joints formed for suctorial purposes.

The order is divided into two sub-orders, Hemiptera-Heteroptera and Hemiptera-Homoptera, and these again are separated into divi-sions and subdivisions, the latter being distributed into families which contain the various genera and species. In the first sub-order (Hemiptera-Heteroptera) there are two divisions, viz., Gymiwcerata and Gryptocerata, and the families comprised under these heads are 69 in number, the following being the generally accepted order in which they are arranged, viz. : Pachycoridce (in this family the scutellum is so enlarged as to cover the whole of the upper side of the abdomen, both pairs of wings being concealed beneath it when not in flight; in one genus at least the species might be mistaken for some of the Buprestidce in Coleoptera, which they resemble in form and brilliancy of colour), Eurygastridce, Podopicke, Odonto-scelidos, Plataspidce, Oxynotidm, Asopidee, Gydnidee, Sciocoridce, Phlceidce (this last contains but one genus, the species of which are most peculiar in appearance, as they resemble small, thin pieces of barkjoined together), Halydidce, Pentatomidce, Urostylidm, Edcssidai, Phylloccphalidw, Megymenidce, Spartoeeridoe, Mictidce, Ncmatopidce, Homceceridce, Syromastidce, Acanthocoridce, Anisoscelidce, Alydidce, Stenocephalidce, Bcrytidaz, Coreidce, Bhopalidac, Lygceidce, Dipso-coridce, Anthocoridm, Microphysidce, Pyrrhocoridce, Largidce, Capsidce, Phymatidce, Macrocephalidm, Hebridm, Zosmenidce, Piesmidce, Tingididce, Brachyrhynchidce, Aradidat, Acanthiidoz, Holoptilidce, Lobocephalidce, Sycanidce, Harpactoridce, Saccoderidce, Hcematoceridce, Tagalidce, Stenopodidos, Reduviidce, Ectrichodidce, Apimneridoz, Piratidoe, Nabida. (the species comprised in the last 12 families are predaceous in their habits, and the larva of one species, Beduvius pcrsonatus, is known to prey upon the common house bug, Acanthia lectularia; some two or three of the species in South America are also known to live with spiders), Saldidce, Pelogonidce, Emesidce, Henicocephalidm, Gerridce, Veliidce, Gal-gulidce, Naucoridce, Belostomidce, Nepidai, Corixidce, and Noto-nectidce (the species pertaining to the last eight families, except the Galgulidce, live either in or on the water, and the genus Belo-stoma contains the largest insect of the order, Belostoma grandis, which measures 34 inches in length by nearly 1J in breadth). In the second sub-order (Hemiptera-Homoptera) there are three grand divisions, viz., Cicadina, PhytopMhires, and Anoplura. The first embraces the families Strid%dantid.ee,Fnlgoridce, Tettigometridce, Membracidce, and Cicadidce; and in these families are to be fnwnd perhaps some of the most curious and wonderful forms of insect life. The well known lantern-fly (Fulgora laternaria, L.) belongs here, and the whole of the stridulating or singing group is also included. The PhytopMhires, or second division, contains three families, viz., Psyllidce, Aphididce, and Coccidce. None of the insects composing this group are of large size, and many of them are only about one line in length, The first family affects trees and plants, in many instances distorting the leaves and buds; one of its species, Rhiiiocola speciosa, has been recorded by Lichtenstein in the annals of the French Entomological Society for 1872 as puncturing poplar leaves which afterwards attain the size and form of a cucumber. The Psyllidce differ from the second family in having the power to leap, their third pair of legs being formed for this purpose. The Aphididce are perha"-" best known by the terms "blight," "green fly," &c. These are to be found almost always in large companies on nearly every kind of tree, plant, and shrub. They are said to produce the honey dew found upon maple and other trees, although this has been disputed by Dr Hooker in the Gardener's Chronicle for July 1873. They are furnished with two setiform pipes or tubes, varying considerably in length in the different species, placed one on each side of the abdomen on the fourth segment from the apex, from which certainly is emitted a sweet fluid which the ants are well known to follow them for and consume. This family also contains the great vine-pest known by the name of Phylloxera vastatrix. The third family, Coccidce, has amongst its members the well-known cochineal insect (Coccus Cacti), from the female of which wdien gathered and killed is obtained the drug or dye used in giving the red colours, scarlet and crimson. It is also used for making carmine. The last division to be dealt with is called the Anoplura, and contains the most degraded forms of the whole order, viz., the lice, the fullest information concerning which may be obtained by consulting the works of Nitzch, Burmeister, Leach, and Denny.





Although the Hemiptera are of very ancient date, remains of some of the fossil forms having been found in the Primary and other formations, the number of these is but few; they are enumerated in a paper on " Fossil Entomology" by Mr H, Goss in vol. xv. of the Entomologist's Monthly-Magazine.

The whole of the group is extremely widely distributed, being found in almost every portion of the globe; and they are very varied both in form and in their modes of life,— man, animals, birds, insects, and plants being subjected to their attacks. On the Continent they have for a long period engaged the attention of naturalists, but in England little was known of the actual number inhabiting these islands until Douglas and Scott in 1865 published their volume of British Hemiptera-Heteroptera, In 1859 Dr A. Dohrn published what may be considered to be the first whole- world catalogue of the order; and, taking it as a basis, for there is no other approximate list, and adding a reasonable amount of new species collected in each year since that time, their number would amount to nearly 10,500 species, 5300 belonging to the heteropterous section and the remainder to the second sub-order. Out of these Europe lays claim to at least 3000, whilst Great Britain is known to possess not fewer than 1000. There is no record of any one of the species being cosmopolitan (except perhaps the house bug, Acanthia lecUdaria), although some of the species inhabiting England are also to be met with in China and Japan. (J. sc.)







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