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Show 328 INSECTA. They also approximate, in some respects, to the Insects of the ceding family, and to the Silphce and Necrophori, (genera 0/;:· fourth) in many others. They commonly have a large, flattene~ head, stout mandibles, short antennce, a thorax as wide as the abdo. men, and the elytra truncated at the extremity, but still covering the wings, which preserve their usual extent. The semi-annuli of the top of the abdomen are as scaly as tho~e of the venter. The vesicles of the anus consist in two coni~al and pilose. points, which are pro. truded and retracted at the will of the ammal; a subtile vapour escapes from them, which, in some species, has a strong odour of sulphuric ether. M. Leon Dufour, Ann. des Sc. Nat. VIII, p. IG, has described the apparatus which produces it. The last segment of the abdomen, that which contains the anus, is prolonged and terminates in a point. These Insects, when touched, or while they run, elevate the extremity of their abdomen and flex it in every direction. They also use it to push their wings under the elytra. The tarsi of their two anterior legs are frequently broad and dilated, and their coxre as well as those of the intermediate legs are very large. They are usually found in earth, dung, and excrementitious matters; some live in mushrooms, rotten wood, or under stones; others are only met with in aquatic localities. Some very small ones keep on flowers. They are all voracious, run with great swiftness, and take wing very promptly. The larva bears a close resemblance to the perfect Insect: it has the figure of an elongated cone, the base of which is occupied by the very large head; the last ring is prolonged into a tube, and is accompanied by two conical and hait·y appendages. It feeds on the same matters as the perfect Insect. The first stomach of the Staphylini is small and without plicre; the second is very long and pilose; the intestine is extremely short(!). It is a very extensive genus, which we will divide into five sec· tions. In the first, or that of the FrssrLABRA, the head is completely ex· posed and separated from the thorax, which is sometimes square or semi-oval, and at others rounded, or cordiform and truncated, by a neck or sensible strangulation. The labrum is profoundly cleft and forms two lobes. Such is the (1) According toM. Dufour, the only essential difference between theiralirnen· tary canal and that of the carnivorous Coleoptera consists iu the absence of the crop. Their biliary vessels are inserted at the same lateral point, and, at least in some species, present near the middle, ,a knot or vesicle, not observed in any other Jnsects. Their sexual apparatus differs greatly from that of the carnivorousCo· leoptera. See Ann. des Sc. Nat., Octob . 1825. COLEOPTERA. 329 OxYPORus, Fab. Where the maxillary palpi are filiform, and those attached to the labium are terminated _by a very large and lunate joint. The antenn: e are large, perfohate and compressed; the anterior tarsi are not dilated; the last joint and then the second are the longest. Th~y inhabit the Boleti and Agarici. 0. rufus; Staphylinua rufus, L.; Panz. Faun. Insect. Germ., XVI, 19, About three lines in length; fulvous; head, pectus, extremity and interior margin of the elytra, as well as the anus, black( 1 )· AsTRAPJEus, Grav. The four palpi terminated by a larger and nearly triangular joint; anterior tarsi greatly dilated, the first and last joints the longest(2). In the STAPHYLINus, Fab. Or the true Staphylini, all the palpi are filiform, and the antennre are inserted between the eyes, above the labrum and mandibles. Some, particularly the males, have the anterior tarsi greatly di. lated, and the antennce separated at base; the length of the first joint of the latter is equal, at most, to that of a fourth of the whole number. The head is but slightly elongated. In some systems, those species alone which present the above chuacters, constitute the genus Staphylinus. The S. dilatatus, Fab., Germ., Faun. Insect. Europ., VI, 14, has even been separated from it, to compose another, on account of its antennce, which form an elongated serrated club. According to the observations of M. Chevrolat, a zealous entomologist, this Insect feeds on caterpillars which it searches for on trees. 8. hirtus, L.; Panz., Faun. Insect. Germ., IV, 19. Ten lines in length; black; very hairy; superior surface of the head, thorax, and last abdominal annuli cove1·ed with thick hairs of a glossy golden-yellow; elytra cinereous-grey, with a black base; under part of the bedy bluish-black. North of Europe, France and Germany. 8. olens, Fab., Panz. ib., XXVII, 1. An inch long; dead (1) Add 0. 1nfJ:1:il!mn~s, Fa b.; Panz. lb. 20. The remaining Oxypori of Fabri· cius belong to subgenera of our fourth section. See Oliv., Encyc. Method., genus Oxypore, and the Coleoptera Microptera, Gravenhorst. (2) Staphylinus ulmi, Oliv.; Ross., Faun. Etrusc., I, v, 6; Panz. lb., LXXXVIII, 4; Latr., Gener. Crust. et Insect., I, 284. VoL. III.-2 R |