OCR Text |
Show 542 INSECTA. In the following Insects, and of the same subdivision, both sexes are furnished with wings, the thorax is tuberculous or spinous laterally, unequal and as if turned up at the two extremities. They compose the genus Rltagium of Fabricius or Stenocorus of Olivier, including also some of the Lepturetre of the former. Later entomologists have thought it best to divide these Insects into five genera, which may be reduced to four. RHAGIUM, Dahl. Or Rhagium properly so called, where the antennre, always simple, are at most half as long as the body, and where the last joint of the palpi forms a triangular club. The head is large, and almost square; the eyes are entire. Each side of the thorax offeJ'S a conical spiniform tubercle( 1 ). RHAMNUSIUM, Meg. Where the antennre, somewhat shorter than the body, are serrated, with the third and fourth joints shorter than the following ones, The eyes are evidently emarginated(2). ToxoTus, PAoHYTA, Meg. Dej. Where the antenncc are at least as long as the body, simple, and with the first joint much shorter than the head; the eyes are entire or but very slightly emarginated. The abdomen is triangular, or forms a long square, narrowed posteriorly(3). STENODERus( 4), Dej.-Cerambyx, Fab.-Leptura, Kirb.-Stenocorus, Oliv. Where the antennre are also long, but their first joint is at least (1) The Rlwg. bifaaciatum, indagator, inquisitor, mordax, Fab. (2) Rlwgium salicis, Fab. (3) See the Catal., of Dejean and Dahl. In the Leptura virginea and col/aris of Fabricius, which I refer to the subgenus Toxotus, the third and fourth joints of the antennre are rather shorter than the fifth. (4) Near the subgenus Stenoderus come DISTENU. and CoMETEs, two genera established by Messrs Lepeletier and Serville, Encyc. Method., X, 485. Their thorax is tuberculous or spinous laterally, which removes them ft·om Stenoderus, where the palpi are also shorter, and the antennre simply furnished with a dense pubescence, and not pilose as in these two subgenera. The elytra of the Diste· nire are gradually narrowed from their humeral angles to their extremity, which is armed with a spine; they are linear and unarmed in Cometes. The species of both subgenera are from Brazil. COLEOPTERA. 543 as long as the head; their ~ody is long, narrow and almost linear. The palp_i also are mor~ salient. The eyes are entire(l). Sometimes the head. 1s abruptly narrowed immediately behind the eyes. The an~enn~, Inserted near the anterior extremity of their internal emargmat10n, are remote at base. The two eminences from which they rise are almost confounded in one plane. The thorax is almost always smooth or without lateral tubercles. They are the LEPTURA, Dej. Dahl. Or Leptura properly so called. In some the thorax is almost plane above, and trapezoidal or conical. Of this number are L. armata, Gyll.; L. calcarata, Fab., the male; L. subspinoaa, ejusd., the female; which is very common in summet• in the woods, on the flowers of the Bramble. The body is elongated and black, the elytra are yellow with four transverse black lines, the anterior of which is formed by points. The antennre are picked in with black and yellow. The posterior tibire of the male are armed with two teeth. L.nigra, L.; Oliv., Col., 73, III, 36. Black and glossy, with a red abdomen. In others, the thorax is much more elevated and rounded, or almost globular. Such is L. tomentosa, Fab.; Oliv., lb., II, 13. Dlack, with a yellowish pubescence on the thorax; elytra of this same colour, and the extremity black and truncated. Very common in the environs of Paris(2). FAMILY V. EUPODA. Our fifth family of the tetramerous Coleoptera is composed of Insects, the first of which so closely approach the last Longicornes that they were confounded both by Linnreus and Geoffroy, and the last are so closely allied to the Chry~ome1re, (1) Leptura ceramboides, Kirby, Lin. Trans., XII, xxiii, 11, and some other spe~ cies from Brazil. (2) See the species called rubra, virens, ltaatata, 2-punctata, acutellata, &c., and as regards the genus, the Catalogues already quoted, the last volume of Gyllenhall's Insect. Suec., and Olivier, Fabricius, &c. |