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ICHNEUMON (Gr. ixveu)

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Originally appearing in Volume V14, Page 243 of the 1911 Encyclopedia Britannica.
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ICHNEUMON (Gr. ixveu) .uv, from ixveveav, to track out), the See also:common name of the See also:North See also:African representative of a number of small See also:weasel-shaped mammals belonging to the carnivorous See also:family Viverrivae; the See also:Indian representatives of the See also:group being known as mongooses. A large number of See also:species of the type genus are known, and range over See also:southern See also:Asia and all See also:Africa, the typical Her pestes ichneumon also occurring in the See also:south of See also:Spain. The latter is an inhabitant of See also:Egypt and the north of Africa, where it is known to See also:foreign residents as " See also:Pharaoh's See also:rat." It is covered with See also:long harsh See also:fur of a tawny-See also:grey See also:colour, darker on the See also:head and along the See also:middle of the back, its legs reddish and its feet and tail See also:black. It lives largely on rats and mice, birds and See also:reptiles, and for this See also:reason it is domesticated. It is, however, fond of poultry and their eggs, and its depredations among fowls detract from its merits as a See also:vermin-killer. During the inundations of the See also:Nile it is said to approach the habitations of See also:man, but at other seasons it keeps to the See also:fields and to the See also:banks of the See also:river. The Indian mongoose (H. mungo) is considerably smaller than the See also:Egyptian See also:animal, with fur of a See also:pale-grey colour, the hairs being largely See also:white-ringed, while the cheeks and See also:throat are more or less reddish. Like the former it is fro- Egyptian Ichneumon (Herpestes ichneumon). quently domesticated. It is especially serviceable in See also:India as a See also:serpent-killer, destroying not only the eggs and See also:young of these creatures, but. killing the most venomous adult See also:snakes. The fact that it survives those encounters has led to the belief that it either enjoys See also:immunity from the effects of snake See also:poison, or that after being bitten it has recourse, as the See also:Hindus maintain, to the See also:root of a plant as an antidote. It has been found, however, that when actually bitten it falls a victim to the poison as rapidly as other mammals, while there is no See also:evidence of its seeking a See also:vegetable antidote.

The truth seems to be that the mongoose, by its exceeding agility and quickness of See also:

eye, avoids the fangs of the snake while fixing its own See also:teeth in the back of the reptile's See also:neck. Moreover, when excited, the mongoose erects its long stiff See also:hair, and it must be very difficult for a snake to drive its fangs through this and the thick skin which all the members of the genus possess. The mongoose never hesitates to attack a snake; the moment he See also:sees his enemy, " his whole nature," writes a spectator of one of those fights, " appears to he changed. His fur stands on end, and he presents the incarnation of intense rage. The snake invariably attempts to See also:escape, but, finding it impossible to evade the rapid onslaught of the mongoose, raises his See also:crest and lashes out fiercely at his little persecutor, who seems to delight in dodging out of the way just in See also:time. This goes on until the mongoose sees his opportunity, when like See also:lightning he rushes in and seizes the snake with his teeth by the back of the neck See also:close to the head, shaking him as a terrier does a rat. These See also:tactics are repeated until the snake is killed." The mongoose is equally dexterous in killing rats and other four-footed vermin. ICHNEUMON-See also:FLY, a See also:general name applied to parasitic See also:insects of the See also:section Ichneumonoidea (or Entomophaga), See also:order See also:Hymenoptera, from the typical genus Ichneumon, belonging to the See also:chief family of that section—itself fancifully so called after the Egyptian mammal (Herpestes). The species of the families (Ichneumonidae, Braconidae, Evaniidae, Proctotrypidae, and Chalcididae are often indiscriminately called " Ichneumons. " but the " super-family " of the Ichneumonoidea in the See also:classification of W. H. Ashmead contains only the Evaniidae, the Stephanidae, and the large assemblage of insects usually included in the two families of the Ichneumonidae and the Braconidae, which are respectively See also:equivalent to the Ichneumones genuini and I. adsciti of older naturalists, chiefly differing in the former having two recurrent nerves to the anterior wing,whiist the latter has only one such See also:nerve.

The Ichneumonidae proper are one of the most extensive See also:

groups of insects. Gravenhorst described some 165o See also:European species, to which considerable subsequent additions have been made. There are 6 sub-families of the Ichneumonidae, viz. the Ichncuntoninae, Cryptinae, Agriotypinae, Ophioninae, Tryphoninae and Pimplinae, differing considerably in See also:size and facies, but See also:united in the common attribute of being, in their earlier stages, parasitic upon other insects. They have all long narrow bodies; a small See also:free head with long filiform or setaceous antennae, which are never elbowed, and have always more than sixteen See also:joints; the See also:abdomen attached to the See also:thorax at its hinder extremity between the See also:base of the posterior coxae, and provided in the See also:female with a straight ovipositor often exserted and very long; and the wings veined, with perfect cells on the disk of the front pair. Ashmead proposes to See also:separate the Agriotypidae (which are remarkable for their aquatic See also:habit, being parasitic on caddis-See also:worms) from the Ichneumonidae on See also:account of their See also:firm ventral abdominal segments and spined scutellum. He also separates from the Braconidae the Alysiidae as a distinct family; they have See also:peculiar mandibles with out-turned tips. Their parasitic habits render these flies of See also:great importance in the See also:economy of nature, as they serve to check any inordinate increase in the See also:numbers of injurious insects. Without their aid it would in many cases be impossible for the agriculturist to hold his own against the ravages of his See also:minute See also:insect foes, whose habits are not sufficiently known to render artificial checks or destroying agents available. The See also:females of all the species are constantly on the alert to discover the proper living See also:food for their own larvae, which are hatched from the eggs they See also:deposit in or on the eggs, larvae or pupae of other insects of all orders, chiefly Lepidoptcra, the caterpillars of butterflies and moths being specially attacked (as also are See also:spiders). Any one who has watched insect See also:life during the summer can hardly have failed to See also:notice the busy way in which the See also:parent ichneumon, a small four-winged fly, with constantly vibrating antennae, searches for her See also:prey; and the clusters of minute cocoons See also:round the remains of some See also:cabbage-butterfly See also:caterpillar must also have been observed by many. This is the See also:work of Apanteles (or Microgaster) glomeratus, one of the Braconidae, which in days past was a source of disquietude to naturalists, who believed that the life of the one defunct larva had transmigrated into the numerous smaller flies reared from it. Ichneumon-flies which attack See also:external feeders have a See also:short ovipositor, but those attached to See also:wood-feeding insects have that See also:organ of great length, for the purpose of reaching the haunts of their concealed prey.

Thus a species from See also:

Japan (See also:Bras-on penetrator) has its ovipositor nine times the length of the See also:body; and the large species of Rh yssa and Ephialtes, parasitic on Sirex and large wood-See also:boring beetles in temperate See also:Europe, have very long See also:instruments (with which when handled they will endeavour to sting, sometimes penetrating the skin), in order to get at their secreted victims. A common reddish-coloured species of Opltion (0. obscurum), with a sabre-shaped abdomen, is noteworthy from the fact of its eggs being attached by stalks outside the body of the caterpillar of the puss-See also:moth (Cerura vinula). Lepidopterists wishing to breed the latter cut off the eggs of the See also:parasite with See also:scissors. The larvae of the ichneumon-flies are white, fleshy, cylindrical, footless grubs; the See also:majority of them spin See also:silk cocoons beforepupating, often in a See also:mass (sometimes almost geometrically), and sometimes in layers of different See also:colours and texture. AuTHORrTIEs.—Among the older See also:works on Ichneumonoidea may be specially mentioned J. L. K. Gravenhorst, Ichneumonologia Europaea (See also:Breslau, 1829); A. H. Haliday (Entom. Mag. i.-v., 1833–1838), and A. See also:Forster (Verhandl.

Naturhist. Ver. Rheinl. u. Westph. xix., See also:

xxv., 1862, 1868). Full reference to the systematic literature of the group will be found in C. G. de Dalla Torre's Catalogus hymenopterorum, vols. iii., iv. (See also:Leipzig, 1898-1902), and a comprehensive See also:summary in W. H. Ashmead's See also:recent memoir (Prot. U.S. Nat. See also:Mus. See also:xxiii., 1901).

For the See also:

British species consult C. See also:Morley, Ichneumons of Great See also:Britain (See also:Plymouth, 1903), and T. A. See also:Marshall (Trans. Entom. See also:Soc., 1885-1899). (G. H.

End of Article: ICHNEUMON (Gr. ixveu)

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