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NEUROPTERA (Gr. vevpov, a nerve, and ...

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Originally appearing in Volume V19, Page 440 of the 1911 Encyclopedia Britannica.
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NEUROPTERA (Gr. vevpov, a See also:nerve, and ,rmpbv, a wing)  , a See also:term used in zoological See also:classification for an See also:order of the class See also:Hexapoda (q.v.) . No ordinal name used in the class has had so many varying meanings given to it by different authors . As first used by See also:Linnaeus (1735) it included all See also:insects with mandibulate jaws and two pairs of See also:net-veined .wings—See also:dragon-flies, May-flies, See also:stone-flies, lacewing-flies and caddis-flies—and it has been employed in the same wide sense by D . See also:Sharp (See also:Cambridge Nat . Hist. vol. v., 1895) . But detailed study of these various See also:groups of insects shows that beneath their See also:common superficial resemblances See also:lie important distinctions in structure, and essential See also:differences in the course of the See also:life-See also:history . Some of the families —the stone-flies, for example—have the See also:young See also:insect much like the adult, growing its wings visibly outside the thoracic segments, and active at all stages of its life . The dragon-flies and May-flies are also active throughout their lives and possess See also:external wing-rudiments, though the young insects differ rather strikingly from their parents . All such families—falling into the See also:group Exopterygota as defined in the classification of the Hexapodawere separated from the See also:Neuroptera by W . E . Erichson (1839) and See also:united with the See also:Orthoptera, with which order some entomologists still See also:associate them under the name of " Pseudoneuroptera." The other groups of the old Linnean order (such as lacewing-flies and caddis-flies)—which are hatched as larvae markedly unlike the See also:parent, develop wing-rudiments hidden under the larval cuticle, and only show the wings externally in a resting pupal See also:stage, passing thus through a " See also:complete " See also:metamorphosis and falling into the sub-class Endopterygotawere retained in the order Neuroptera, which thus became much restricted in its extent . More recently the subdivision of the Linnean Neuroptera has been carried .still further by the separation of the caddis-flies and See also:scorpion-flies as distinct orders (Trichoptera and Mecaptera respectively), and by the withdrawal of the " Pseudo-neuroptera " from the Orthoptera—with whose typical families they have little in common—and their See also:division into a number of _small orders .

Altogether, eight orders are recognized in the classification adopted here, the first five of these belonging to the sub-class Exopterygota and the last three to the Endopterygota (see HEXAPOD) . The multiplication of orders is attended with See also:

practical difficulties, and the distinctions between the various groups of the Linnean Neuroptera are without doubt less obvious than those between the See also:Coleoptera (beetles) and the See also:Diptera (two-winged flies) for example . But if classification is to See also:express relationship, it is impossible to associate in the same order families whose kinship to insects of other orders is nearer than their kinship to each other . And no student can doubt that the stone-flies are akin to Orthoptera and the caddis-flies to the See also:Lepidoptera, while dragon-flies and May-flies stand in an isolated position with regard to all other insects . In the See also:present See also:article. for the See also:sake of convenience, all the insects which have been regardedby Linnaeus and others as "Neuroptera" are included, but they are distributed into the orders agreed upon by the See also:majority of See also:modern observers, and See also:short characters of these orders and their See also:principal families are given . For further details the reader should consult the See also:special articles on these groups, to which See also:cross-references will be found . Sub-class EXOPTERYGOTA Order Plecoptera . This order was founded (1869) by F . Brauer—the name having been See also:long previously suggested by H . Burmeister (1832)—to include the single See also:family of the Perlidae or stone-flies . They resemble the Orthoptera more nearly than do any other group of the Linnean Neuroptera, having the anal See also:area of the See also:hind-wings folding fanwise beneath the costal area and the whole hind-wing covered by the fore-wing when the insect is at See also:rest, though the forewing is not firmer in texture than the hind-wing, as is the See also:case in the Orthoptera . In the See also:opinion of J .

H . Comstock and J . G . Needham the wing-neuration in this order is the most See also:

primitive to be found in the Hexapoda . The tenth abdominal segment carries a pair of jointed cerci which are often elongate, and the feelers are always long, while the jaws are usually feeble and membrancus, though the typical parts of a mandibulate mouth are present—mandibles, maxillae with inner and See also:outer lobes and palps, and second maxillae (labium) whose lacinae are not fused to See also:form a ligula . Both See also:head and See also:trunk are somewhat flattened dorso-ventrally, giving the insects a very distinct and characteristic aspect . The stone-flies further resemble the Orthoptera in their numerous Malpighian excretory tubes, which vary in number from twenty to sixty . The reproductive See also:organs, both ovaries and testes, become fused together in the See also:middle of the See also:body . A remarkable point in the Plecoptera is the presence in some forms (Pteronarcys) of small branching gills on the three thoracic and the front abdominal segments . These organs appear, however, from the observations of H . A . See also:Hagen not to be functional in the adult insect—they are merely survivals from the aquatic nymphal stage .

Life-history and Habits.—The See also:

nymphs of the Perlidae are closely like their parents and breathe dissolved See also:air by means of tracheal gills on the thoracic segments, for they all live in the See also:water of streams . They feed upon weaker aquatic creatures, such as the larvae of May-flies . The perfect insects, whose See also:flight is feeble, are never found far from the water . A curious feature among them is the frequent reduction of the wings in the See also:males of certain See also:species, contrary to the usual See also:condition among the Hexapoda, where if the sexes differ in the development of their wings it is the See also:female which has them reduced . The Plecoptera are See also:world-wide in their range and fossils referable to them have been described from rocks of See also:Eocene, See also:Miocene and See also:Jurassic See also:age, while C . See also:Brongniart states that allied forms lived in the Carboniferous See also:Period . Order Isoptera . The two families included in this order agree with the Plecoptera in the young insect resembling the parent, but they are all terrestrial d e b C f After C . L . Marlatt, Ent . See also:Bull . 4 (N.S.), U.S .

Dept . Agric . a, Male from above. b and c, Hind segments of male and female abdomens, showing short d, Male from See also:

side. cerci . e, See also:Abdomen of female from f, End of shin and See also:foot-segments. side . throughout life . The hind-wings have no folding anal area and the wings of both pairs, when present, are closely alike (see fig . I) whence the name Isoptera (=equal winged) lately applied to the group by G . Enderlein . The See also:eleventh abdominal segment which carries the short jointed cerci (fig . I, b, c) may remain in a reduced condition distinct from the tenth . There are only six or eight Malpighian tubes—contrasting with the large number of these excretory organs found in the Orthoptera and Plecoptera . The Embiidae are feeble, somewhat soft-skinned insects with the prothorax small and the mesothorax and metathorax elongate .

The feelers are long and See also:

simple, and the wings are very narrow, each with a sub-costal, a radial, a median and a cubital nervure; the branches of the median and the cubital, however, as well as the anal nervures, are vestigial, and there are a few short cross-bars between Q After Marian, Ent . Bull . 4 (N.S.), U.S . Dept . Agric . the radial and the median . Some Embiidae are entirely wingless in the adult See also:state, and it has been suggested that this is always the condition in the female See also:sex . According to the See also:recent investigations of K . W . Verhoeff, the family contains only thirteen known species . The Embiidae live in warm countries, and are very retiring in their habits, hiding under stones where they spin webs formed of See also:silk produced by glands in the basal segments of the fore-feet . The Termitidae (so-called " See also:white ants ") are the other family of Isoptera .

They are relatively shorter and broader insects than the Embiidae with large prothorax and long wings, which have a trans-See also:

verse See also:line of weakness at the See also:base and are usually See also:shed after the nuptial flight . The Termitidae are numerous in species in warm countries . The vast majority of individuals in a community consist of wingless forms—" workers " and " soldiers," which are undeveloped members of either sex . Their See also:economy is fully described in a special article on TERMITES . Order Corrodentia . The insects included in this order differ from those of the two preceding orders in their more condensed abdomens which See also:bear no cerci, while the number of Malpighian tubes is reduced to four . In the See also:absence of cerci the Corrodentia are more specialized than the Isoptera and Plecoptera, but some of them show a more primitive See also:character in the retention of vestigial maxillulae—the See also:minute pair of jaws that are found behind the mandibles in the See also:Aptera (Q.v.) . A large proportion of the Corrodentia are wingless . When wings are present the front pair are much larger than the hind pair, and the neuration is remarkable for the concresence of the median with the b After Marlatt, Bull . 4 (N.S.), Div . Ent . U.S .

Dept . Agric . a, From below. c, Second maxillae . b, From above, (eyes, feeler, feet d, Mandible . and claws more highly mag- e, Lacinia or " pick " of first nified). maxilla . f, Its palp . Highly magnified . cubital trunk, and the zigzag course of many of the branches . All the insects of this order are of small See also:

size and the cuticle is imperfectly chitinized, so that the body as a whole is soft . The name Corrodentia was first used by H . Burmeister (1832) and has reference to the biting habits of the insects . Originally, however, the Corrodentia included the order which Enderlein has recently separated as Isoptera (see above) .

Phoenix-squares

As at present restricted, the Corrodentia include two distinct sub-orders . Copeognatha.—This sub-ordinal name has been applied by Enderlein to the " See also:

book-lice." These frail insects, the majority ofwhich have wings of the type described above, are further characterized by the presence of minute but distinct maxillulae, while the inner See also:lobe (lacinia) of the first maxilla is an elongate, hard structure (the " pick," fig . 3, e) and the outer lobe is See also:convex and soft . The labial (second maxillary) palps are reduced to small, rounded prominences external to the still smaller prominences that represent the lobes (fig . 3, c) . The feelers of these insects are elongate and See also:thread-like, consisting of from a dozen to nearly See also:thirty segments . The prothorax is very small . The book-lice are See also:familiar wingless insects, often found in houses See also:running about among old papers and neglected biological collections . They belong to the family Psocidae which has a few See also:score species—most of them winged—living out of doors on the bark of trees and among See also:vegetable refuse . In some Psocidae the wings are in a vestigial state, and the fully winged species rarely if ever See also:fly . H . A .

Hagen observed that some genera possess wing-like outgrowths on the prothorax, comparable to those seen in certain insects of the Carboniferous Period . The Psocidae themselves have not been traced back beyond the Oligocene, in the See also:

amber of which period their remains are fairly numerous . Mallophaga.—This term was first applied by C . L . See also:Nitzsch (1818) . to the degraded wingless parasites (fig . 4) commonly known as See also:bird-lice or biting-lice, differing from the true lice (see See also:HEMIPTERA, See also:LousE) by their jaws adapted for biting (not for piercing or sticking) . By their structure they are evidently allied to the Copeognatha . They are abundantly distinct, however, through the short feelers with only three to five segments and the conspicuous prothorax . The head is relatively very large, but the eyes are degraded and often absent . A remarkable feature is the frequent concrescence of mesothorax and metathorax and in some cases, even, their See also:fusion with the anterior abdominal segments . The legs are stout and spiny, and well adapted for clinging to the See also:hair or feathers of the See also:host See also:animal . It is usual to See also:divide the Mallophaga into two families—the Liotheidae, possessing labial palps and two foot-claws, being fairly active insects, which are capable, on the See also:death of their host, of seeking another, and the Philopteridae, without labial palps and with a single foot-claw modified for clasping (fig .

4) which never leave the host and perish themselves soon after its death . Order Ephemeroptera . This order includes the single family of the Ephemeridae or May-flies . The name, although quite recently proposed by A . E . See also:

Shipley, should be used rather than A . S . Packard's older term Plectoptera on See also:account of the See also:great liability of confusion between the latter and Plecoptera . The May-flies are remarkably primitive in certain of their characters, notably the elongate cerci, the paired, entirely mesodermal genital ducts, and the occurrence of an ecdysis after the acquisition of functional wings . On the other See also:hand, the reduced feelers, the numerous Malpighian tubes (40), the large complex eyes, the vestigial condition of the jaws, the excessive size of the fore-wings as compared with the hind-wings and their complex neuration with an enormous number of crossnervules are all specializations . So in some respects is the life-history, with a true larval preparatory stage, unlike the parent form, and living an aquatic life, breathing dissolved air by means of a paired See also:series of abdominal tracheal gills . Except for its aquatic adaptations, however, the ephemerid larva is wonderfully thysanuran in character, and possesses conspicuous and distinct maxillulae .

See special article on MAY-FLIES . Order Odonata . The distinctness of the dragon-flies from other insects included in Linnaeus's Neuroptera was long ago recognized by J . C . See also:

Fabricius, who proposed for them the ordinal name of Odonata (1775) . They resemble the May-flies in their " hemimetabolous " life-history; the young insects are markedly unlike their parents, inhabiting fresh water and breathing dissolved air, either through tracheal gills at the tip of the abdomen, or by a branching See also:system of air-tubes on the walls of the rectum into which water is periodically admitted . The winged insects resemble the May-flies in their short feelers and in the large number (5o to 6o) of their Malpighian tubes, but differ most strikingly from those insects in their strong well-armoured bodies, their powerful jaws adapted for a predaceous manner of life, and the See also:close similarity of the hind-wings to the fore-wings . All the wings are of See also:firm, glassy texture, and very complex in their neuration; a remarkable and unique feature is that a See also:branch of the See also:radius (the radial sector) crosses the median nervure, while, by the development of multitudinous cross-nervules, the wing-area becomes divided into an immense number of small areolets . The tenth abdominal segment carries strong, unjointed cerci, while the presence of reproductive See also:armature on the second abdominal segment After See also:Osborn, Ent . Bull . 7 (0.S.), U.S . Dept .

Agric . 440 of the male is a character found in no other order of the Hexapoda . See special DRAGON-FLY . Sub-class ENDOPTERYGOTA Order Neuroptera . The insects retained in the order Neuroptera as restricted by modern systematists are distinguished from the preceding orders by the presence of a resting pupal stage in the life-history, so that a " complete metamorphosis Is undergone . Structurally the Neuroptera are distinguished by elongate feelers, a large, See also:

free prothorax, a labium with the inner lobes of the second maxillae fused together to form a median ligula, membranous, net-veined wings without hairy covering, those of the two pairs being usually alike, the absence of abdominal cerci, and the presence of six or eight Malpighian tubes . The larvae are active and well-armoured, upon the whole of the campodeiform " type, but destitute of cerci; they are predaceous in See also:habit, usually with slender, sickle-shaped mandibles, wherewith they See also:pierce various insects so as to suck their juices . The order contains nine families, most of which are wide in their See also:geographical See also:distribution . Fossil Neuroptera occur in the See also:Lias and even In the Trias if the relationships of certain larvae have been correctly surmised . The Sialidae or See also:alder-flies (q.v.) differ from other Neuroptera in the jaws of the larva—which is aquatic, breathing by paired, jointed abdominal gills—resembling those of the imago, and being adapted for the mastication of solid See also:food . Some See also:American genera (Corydalis) which belong to this family are gigantic among insects and their males possess enormous mandibles . The Raphidiidae or snake-flies (q.v.) are remarkable for the long, narrow, tapering prothorax which gives the See also:appearance of a constricted See also:neck, while the female has a long ovipositor .

Both these families are very sparingly represented in our See also:

fauna . The Myrmeleonidae are large insects with short clubbed feelers on their prominent heads, and two pairs of closely similar net-veined wings, with See also:regular oblong areolets at the tips . Their predaceous, suctorial larvae are the well-known See also:ant-lions (q.v.) . No members of this family inhabit our islands, though a few species occur in neighbouring parts of the See also:continent . The same Is the case with the allied Ascalaphidae, which are distinguished from the Myrmeleonidae by their elongate feelers—as long as the body—and by the irregular apical areolets of the wings . The curious Nemopteridae have slender feelers and very long strap-shaped hind-wings . The Mantispidae are remarkable among the Neuroptera for their elongate prothorax, raptorial fore-legs and hypermetamorphic life-history, the young campodeiform larva becoming transformed into a See also:fat eruciform See also:grub parasitic on young See also:spiders or See also:wasp-larvae (see See also:MANTIS-FLY) . The last-named two families are confined to warm regions of the See also:earth . The lacewing-flies (q.v.), however, of which there are two families, the Hemerobiidae and Chrysopidae, whose larvae feed on Aphids, sucking their juices, are represented in our fauna . So are the tiny Coniopterygidae, which are covered with a white powdery secretion, and have very small hind-wings . Their larvae resemble those of the lacewings, attacking See also:scale-insects and sucking their juices . Order Mecaptera .

This small order was founded (1869) by F . Brauer—under the name of Panorpata—for the small family of the Panorpidae or scorpion-flies (q.v.) . The name Mecaptera Is due to Packard . They may be distinguished from the Neuroptera by the See also:

elongation of the head into a See also:beak, the small prothorax, the narrow, elongate wings with predominantly See also:longitudinal neuration, the presence of abdominal cerci and the eruciform larva . They are generally but sparingly distributed over the earth's See also:surface and can be traced back in See also:time to the See also:early Jurassic See also:epoch . Order Trichoptera . The caddis-flies (q.v.) constitute this order, the name of which (suggested by H . Burmeister) indicates the hairy covering of the wings . They are abundantly distinct from the Neuroptera and Mecaptera, through the absence of mandibles in the imago, the maxillae—both pairs of which possess the typical inner and outer lobes and jointed palps—forming a suctorial apparatus . The feelers are long, slender and many-jointed . While the fore-wings are elongate and narrow, the hind-wings are broad, with a folding anal area . At the base of each wing projects a dorsal lobe—the jugumand the neuration is predominantly longitudinal, resembling so closely that of the See also:lower Lepidoptera (q.v.) that a nearer relationship of the Trichoptera to that order than to any group of the old Linnean Neuroptera is certain .

Fossil Trichoptera occur in rocks of Liassic age . Frequently the whole of the Trichoptera are included in a single family, but most special students of the order recognize seven families . In all Trichoptera the maxillary palps of the female are five-segmented . The family Phryganeidae have males with four-segmented hairy palps; the larvae inhabit stagnant water and See also:

hake cases of vegetable fragments . In the Limnephilidae the maxillary palp is three-segmented in the male, the larvae are variable in habit, many forming cases of See also:snail-shells . The males of the Sericostomatidae have two or three segmented palps; their larvae inhabit running water and make cases of grains of See also:sand, or of small stones . In the13,002 . It has three Evangelical churches, one of which belongs to the See also:Herrnhut brotherhood, a See also:Roman See also:Catholic See also:church and an orphanage . Its largest See also:industry is, perhaps, the manufacture of thread; there are also in the See also:town ironworks, breweries, See also:shipbuilding yards and See also:electrical See also:works . See also:Neusalz became a town in 1743 . See Bronisch, Geschichte von Neusalz an der See also:Oder (Neusalz, 1893) .

End of Article: NEUROPTERA (Gr. vevpov, a nerve, and ,rmpbv, a wing)
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