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WASP (Lat. vespa)
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See also:WASP (See also:Lat. vespa) , the See also:common name for a well-known sort of stinging See also:insect. The See also:order See also:Hymenoptera is divided into two sub-orders, the Symphyta and the Apocrita. The latter is subdivided into several sections, one of which, the Vespoidea, includes all the true wasps; in addition to the See also:ruby wasps and many of the " Fossores " or digging wasps. The true wasps (forming the old See also:section Diploptera) are in their turn divided into three families—(1) the Vespidae, (2) the 1889–1893 1893–1897 1897–1901 1901-1905 1905-1909 1909 1909- Eumenidae, and (3) the Masaridae, which together comprise some I boo different See also:species. They are characterized by their wings, which are See also:present in both sexes and also in the modified See also:females or workers, being longitudinally folded when at See also:rest, except in the Masaridae. The antennae are usually elbowed, and contain twelve or thirteen See also:joints; in some cases they are clavate. A pair of notched faceted eyes are present, and three ocelli in the See also:top of the See also:head. The mouth-parts are arranged for sucking, but have not reached that degree of perfection found amongst the bees. Hence wasps cannot obtain the sugary secretion from deeply-seated nectaries, and their visits to See also:flowers are confined to such as are shallow or widely opened; they particularly frequent the See also:Umbelliferae. The maxillae are elongated, and compressed, the maxillary palp six-jointed. The labium is prolonged centrally into a " See also:tongue," which is glandular at the tip; the paraglossae are linear. The labial palp has three or four joints. The See also:pro-See also:thorax is See also:oval, and its sides are prolonged backward to the See also:base of the wings. The fore wing has two or three submarginal cells. The legs are not provided with any adaptations for See also:collecting See also:pollen. The See also:abdomen is sometimes pedunculate, its second (apparently first) segment being See also:drawn out into a See also:long stalk, which connects it with the alitrunk, made up of the thorax and the first abdominal segment. The queens and the workers are armed with a powerful sting. The usual See also:colour of these See also:insects is See also:black, relieved to a greater or less degree by spots and patches of yellow or See also:buff. The Diploptera may be subdivided into two See also:groups in accordance with the habits of See also:life of the insects comprising the section. One of the groups includes the See also:family Vespidae, which is composed of social wasps, and includes the hornet (Vespa crabra) and the common wasp (V. vulgaris). The other See also:group contains two smaller families, the Eumenidae and the Masaridae, the members of which are solitary in their mode of life. Family i. Vespidae.—In addition to their social habits the members of this family are characterized by certain structural features. The anterior wings have three submarginal cells. The antennae have thirteen joints in the See also:males and twelve in the females; the claws of the tarsi are See also:simple; the anterior four tibiae have two spines at the tip; the abdomen is but rarely pedunculated, and the posterior segments are often very contractile. dThe members of this family approximate very closely to bees in their social manner of life. The communities are composed of males, fertile females and workers. The latter are females in which the ovary remains undeveloped; they resemble the perfect See also:female in See also:external See also:appearance, but are slightly smaller. It has been shown by P. Marchal that a clear See also:line of distinction between See also:queen and worker cannot always be drawn. Unlike the hive bees', the wasps' community is See also:annual, existing for one summer only. Most of the members See also:die at the approach of autumn, but a few females which have been fertilized hibernate through the See also:winter, sheltered under stones or in hollow trees. In the See also:spring and with the returning warm See also:weather the female regains her activity and emerges from her hiding-See also:place. She then sets about finding a convenient place for See also:building a See also:nest and establishing a new See also:colony. The common wasp (V. vulgaris) usually selects some burrow or hole in the ground, which, if too small, she may enlarge into a chamber suitable for her purpose. She then begins to build the nest. This is constructed of small See also:fibres of old See also:wood, which the wasp gnaws, and kneads, when mixed with the secretion from the salivary glands, into a sort of See also:papier-mache pulp. Some of this is formed into a See also:hanging See also:pillar attached to the roof of the cavity, and in the See also:lower See also:free end of this three shallow See also:cup-like cells are hung. In each of these an See also:egg is laid. The foundress of the society then continues to add cells to the See also:comb, and as soon as the grubs appear from the first-laid eggs she has in addition to tend and feed them. The development within the egg takes eight ap. he grubs are apodal, thicker in the See also:middle than at either end ; the mandibles See also:bear three See also:teeth; the maxillae and labium are represented by fleshy tubercles. The See also:body, exclusive of the head, consists of thirteen segments, which bear lateral tubercles and spiracles. The larva has no anus. The larvae are suspended with the head downwards in the cells, and require a See also:good See also:deal of See also:attention, being fed by their See also:mother upon insects which are well chewed before they are given to the larvae, or upon See also:honey. At the same See also:time the mother is enlarging and deepening the cells in which they live, building new cells, and laying more eggs, which are usually suspended in the same See also:angle of each See also:cell. After about a fortnight the grubs cease to feed, and, forming a silky See also:cover to their cells, become pupae. This quiescent See also:stage lasts about ten days, at the end of which See also:period they emerge as the imago or perfect insect. The silky covering of the cell is See also:round or See also:convex outwards; and to leave the cell the insect either pushes it out, whenit opens like a See also:box lid, or gnaws a round hole through it. As soon as the cell is vacated it is cleaned out and another egg deposited. In this way two or three larvae occupy successively the same cell during the summer. The first wasps that appear in a nest are workers, and these at once set to See also:work to enlarge the comb, and feed the larvae, &c. The material of the nest, as before stated, is usually dried wood, worked by the mandibles of the wasp, with the addition of its salivary secretion, into a pulp, which can easily be moulded whilst moi.,t; it dries into a substance of a papery appearance, but possessing considerable tenacity. Sometimes See also:paper itself, such as old See also:cartridge cases, is used. The combs are#rranged horizontally; each contains a single layer of cells opening downwards. The second comb is suspended from the first by a number of hanging pillars which are built from the point of See also:union of three cells. The space'between two combs is just sufficient to allow the wasps to See also:cross each other. The combs are roughly circular in outline, and increase in See also:size for the first four or five layers, after which they begin to decrease; the whole is covered by a roughly made coat?ng consisting of several layers of the same papery substance which composes the combs. This is continued down until it forms a roughly spherical covering for the whole, but not giving any support to the combs, which are See also:independent of it. As the nest increases in size, the covering needs to be repeatedly pulled to pieces and reconstructed, its inner layer being cut away as the combs are enlarged. The covering is pierced by apertures for the passage of the wasps. The cells are hexagonal at their mouths, but above become more rounded in their cross section. During the first See also:half of the summer workers only are produced, but, as See also:fruit ripens and See also:food becomes more abundant, fully See also:developed females and males appear, the latter often from parthenogenetically developed eggs of the later broods of workers. The males and females are larger than the workers, and require larger cells for their development; these are usually kept apart from one another and from those of the workers. The males may be distinguished by their longer antennae, by the more elongated outline of their body, and by the See also:absence of a sting. In a favourable See also:season, when the weather is warm and food plentiful, a nest may contain many thousands of cells full of wasps in various stages of development; and, as each cell is occupied two or three times in the course of a summer, those authorities who put the number of the members of the community as high as 30,000 are probably not far wrong. At the approach of autumn the society begins to break up; the males fertilize the females whilst flying high in the See also:air. They then die, often within a few See also:hours. The workers leave the nest, carrying with them any grubs that remain in the cells, and both soon perish. The nest is entirely deserted. The fertilized females, it has been seen, creep into crevices under stones or trees, or hide amongst See also:moss, and hibernate until the warmth of the following spring induces them to leave their hiding-places and set about See also:founding a new community. There are altogether seven species of Vespa met with in See also:Britain. V. vulgaris, the common or ground wasp, V. rufa, the red wasp, distinguished by its reddish-yellow abdomen, and V. germanica, the See also:German wasp, with three black spots upon its first abdominal segment, are classed together as ground wasps. They build their nests in burrows in the ground, but this is not an invariable See also:rule; they may be distinguished from the See also:tree wasps by their shorter cheeks and usually by the first See also:joint in the antennae of the female being black. Vespa austriaca (arborea) is a See also:race of V. rufa, in whose nest it sometimes lives as an inquiline. The tree wasps build stouter nests upon branches of trees; the first joint of the antennae of the females is yellow in front. The tree wasps are V. sylvestris, norvegica and crabro. The hornet, V. crabro, is the largest species occurring in See also:Great Britain. They have a more distinctly red colour than the common wasp, and a See also:row of red spots upon each See also:side of the abdomen. They occur much more rarely than the common wasp, and appear to he almost confined to the See also:southern half of See also:England. Their nests resemble those described above, but are larger; they are found in hollow trees or deserted out-houses. Their communities are smaller in number than those of the other wasps. The hornet, where it occurs in any number, does a considerable amount of damage to See also:forest trees, by gnawing the bark off the younger branches to obtain material for constructing its nest. It usually selects the ash or See also:alder, but sometimes attacks the See also:lime, See also:birch and See also:willow. Like the wasp, it does much damage to fruit, upon the juices of which it lives. On the other See also:hand, the wasp is useful by keeping down the See also:numbers of flies and other insects. It catches these in large numbers, killing them with its jaws and not with its sting. It then tears off the legs and wings, and bears the body back to its nest as food for the larvae. Wasps also See also:act to some extent as See also:flower fertilizers, but in this respect they cannot compare with bees; they visit fewer flowers, and have no adaptations on their limbs for carrying off the pollen. The genus Vespa is very widely spread; it contains over See also:forty species, distributed all over the See also:world. Some of the largest and handsomest come from eastern See also:Asia. V. mandarina of See also:China and See also:Japan, and V. magnifrca of the See also:East Indies and See also:Nepal, measure 2 in. across the wings; V. orientalxs, found in See also:Greece, See also:Egypt and the East, builds its nest of See also:clay. The only other genus of Vespidae which is found in See also:Europe is Polistes, which occurs in the countries bordering the Mediterranean. The colonies of this genus are much smaller than those of Vespa. Each nest consists of a single tier of cells in the See also:form of a round See also:plate, sup-ported in the middle by a single stalk. This comb is sometimes See also:vertical, the cells then being See also:horizontal or slightly oblique. Some of the members of this genus See also:store up honey, which in the See also:case of a See also:South See also:American species is poisonous, from the nature of the flowers from which it is gathered. The members of this genus have a slender body; the thorax is more oblong than in the genus Vespa, the palps are stouter and the abdomen is more distinctly pedunculate. The genus Ischnogaster, from the East Indies, has many structural features in common with the Eumenidae, but the See also:character of its communities, and its nest, which is very small, justify its position amongst the social wasps. The genus Icaria, common in See also:Australia and the East Indies, builds very small nests, of two or three rows of cells, hanging on one side from a stalk. Synaeca is a South American genus, which builds large nests, sometimes 3 ft. in length, closely applied to the See also:branch of a tree; they never contain more than one layer of cells, which are horizontally placed. The whole nest is built of coarse material, chiefly small pieces of bark; and there is only one opening, at the lower end. Another South American genus, Chartergus, makes a tough nest, pendent from boughs of trees, and opening to the exterior below by a median See also:aperture. The combs are arranged, somewhat like funnels, inside one another, but with spaces between. The See also:apex of each comb is pierced by a hole for the wasps to pass from one See also:gallery to another. The nest of Tatua, which occurs in See also:Mexico and. South See also:America, is also pendent, but the combs are horizontal; the opening from the exterior is at the side, and the passage from one gallery to another is also lateral. The external appearance of the nest of Nectarina, found in See also:Brazil and other parts of South America, resembles that of the comrnon wasp, but is rougher. Internally the combs are arranged concentrically, more or less parallel with the external covering which affords them support. The members of the two remaining families, the Eumenidae and the Masaridae, resemble one another in their solitary mode of life; only males and normal females exist—no workers being found. Family 2. Eumenidae. Solitary species, with three submarginal cells in the fore wing; antennae with thirteen joints in the male, twelve in the female; abdomen sometimes pedunculate, posterior segments contractile. In the foregoing structural features the Eumenidae resemble the Vespidae, but they differ in having bifidclaws on their tarsi, and the two anterior tibiae have but one spine at the tip. The mandibles are elongated, and form a See also:kind of rostrum, in this respect approaching the Fossores. See also:Eumenes coarctala is the only See also:British species of this genus. The female is z in. long, the male somewhat shorter. The abdomen is connected with the thorax by a long peduncle. The colour is black, relieved by spots of yellow. It constructs small spherical cells of mud, which are found attached to stems of See also:plants, very generally to the See also:heath. At first the cell opens to the exterior by means of a round See also:pore; one egg is deposited in each cell, and a store of honey as food for the larva when hatched; the cell is then closed with mud. The larvae of some species are carnivorous, and then the food-See also:supply stored up in the cell consists of caterpillars and other insect larvae which have been paralysed by the See also:parent wasp FIG. q. stinging thern through the cerebral ganglion; Eumenes smathii. when the larva of the Eumenes emerges from the egg it sets upon these and devours them. The genus Odynerus contains a very large number of species, found in all parts of the world. The members of this genus are about the size of a See also:fly, and they differ from Eumenes in having a sessile abdomen. Some of the species construct their cells in See also:sand-heaps, lining them with agglutinated grains of sand; others live in cavities of trees lined with the same material, whilst others build their nests of mud. Like some of the species of Eumenes, they store up paralysed Lepidopterous and Chrysomeleous larvae as food for their carnivorous grubs. Family 3. Masaridae.—The members of the third family, the Masaridae, are sharply distinguished by the See also:possession of only two submarginal cells in the fore wing, which folds imperfectly or not at all when at rest. Their antennae are frequently clavate, particularly so in the genus Celonites; they are twelve-jointed, but as the terminal joints are almost fused they appear to be composed of only eight joints. The wings are not so completely folded as in the other two families, and the abdomen is but slightly contractile. The maxillae are See also:short and their palps very small, with but three or four joints. The number of genera comprised in this family is small; none occur in Britain, but in southern Europe some species are found. They make their nest in cavities in the See also:earth, generally in a See also:bank, and construct an irregular gallery leading down to it. During hot See also:fine summers wasps cause a good deal of loss to See also:market gardeners and fruit growers. During this time of See also:year they live almost exclusively upon the sweet juices of ripe fruit, occasionally carrying off small particles of the flesh. At the same time they have not entirely lost their carnivorous tastes, for they frequently attack the See also:meat in See also:butcher's shops, but render See also:compensation by killing and carrying off to feed their grubs considerable numbers of See also:blow-flies. Wasps also perform an important service in keeping down the numbers of cater-pillars. The larvae are almost exclusively carnivorous, living upon insects captured by their parents and reduced by them to a pulp before being given to the See also:young. During the spring the first broods that appear live largely upon honey; and this forms the See also:staple food of the genus Polistes throughout their whole life. In attempting to rid a See also:district of wasps, unless the nest can be taken, there is little good in killing stray members of the community. On the other hand, the killing of queen-wasps in See also:early spring probably means that the formation of a nest and the See also:production of a society whose members are counted by thousands is in each case prevented. The number of wasps is kept down by numerous enemies. The most effective of these live in the nests and devour the larvae; among them are two species of See also:beetle, Rhipiphorus paradoxus and Lebia linearis. Two species of See also:Ichneumon, and a species of Anthomyia, also infest the nests of wasps and See also:prey upon the grubs. The larvae of the syrphid flies Volucella, found in the nests of both wasps and bees, are now believed to be scavengers rather than parasites. Additional information and CommentsThere are no comments yet for this article.
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