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Show 456 . INSECTA. Here th~ anterior edge of the head is ahyays emarginated. The two anterior tarsi of the males are alone manifestly wider, or more dilated than the following ones. PEnrNus, Lat. M. Megerle and count Dejean have divided them into several other subgenera, hut without giving their characters. Those, where the males have the four first joints of the anterior tarsi of the same width, with the radical triangular, the three follow. ing transversal and almost equal, all the tibic:e narrow and elongated, the thorax narrowed posteriorly and .t erminated by acute angle.s , form the genus 0PATRINUS of Count Dejean. · They all belong to America( 1 ). Those, where the same tarsi, and in t)le same sex have the first joint, and particularly the fourth, sensibly narrower or smaller than · the two that are intermediate, and in which the thorax is narrowed near the posterior angles, form four other subgenera, the characters of which are so faint and blended that they may all be united in one, that of DENDARtrs, Meg. Dej. ' In some species, as in ,Opatrinus, the tibic:e are narrow, elongated, but slightly dilated at their extremity and almost identical in both sexes; and the thorax is abruptly narrowed on each side near the posterior angles, which form a small acute tooth: they form the Dendari, properly so called(2). In the following, the four anterior tibic:e, or at least the two first, are dilated triangularly at the extremity. The body is oval. Such is the HELIOPHILUS of Count Dejean. Sometimes the thorax ter· minates insensibly on each side in an acute angle. · The body is ' proportionally shorter and wider. ' Certain species, with a large thorax hardly wider than it is long~ with a strong lateral border, and in which the body is but slightly convex above, compose the genus EuRYNOTus of Kirby(3). Others, in which the body is evidently more convex above, and the thorax is transversal and but very slig-htly bordered, form the Iso· oEnus, Meg. Dej.( 4) ( 1) Blapa clathrata, Fab. ;-B. punctata, Fab., and perhaps his Platynotu8 dila· w~ . , (2) See Catalogue, &c., Dej., p. 65, and the PlcttynotU& excavatua,· and crenatm, Fab. (3) Euryrwtus muricatua, Kirb., Lin. Trans., XII, xxii, 1. See Platynotm 1tri· alm, Schcenh., Synon. Insect., I, 1, tab. ii, 6, (4) Catalogue, &c., Dej., p. 65. • COLEOPTERA. 457 In the males o~ the last of the Pedini, the three first joints of the two anterior tarst, always strongly dilated, diminish progressively in breadth, and the fourth is ~ery small. The posterior thi hs of the same m. d 'l V'ld ua I s are. concave and silky underneath( I); theg b ody is o~al and t~e thorax slightly bo.rdered, widening from before posteriorly or shghtly narrowed behmd, always terminated posteriorly and insensibly by a prolonged and pointed angle. Such are the true Pedini of Dejean or the PEniNus, Dej.(2) There, the anterior m~rgin of the head is entire or unemarginate in several. The four anterior tarsi of the males are equally 01• almost equally dilated. The form of the body, and that of the ~borax in particular, is still similar to that of the last Pedini. Those, in which the anterior margin of the head still presents an emargination, form the genus BLAPTINus, Dej.(3) Those in which it is entire or unemarginate, the PLATYSOELis, Lat.( 4) We now come to Melasoma, provided with wings. Their body is usually oval or oblong, depressed or but slightly elevated; their thorax square or trapezoidal, and its posterior extremity as wide as the abdomen. The pal pi are larger at the extremity ; the last joint of the maxillary palpi has the figure of a reversed triangle, or is secnriform; the mentum is but slightly extended in width( 5), and leaves the base of the maxillre exposed. These Insects compose the third and last tribe of the Melasoma, that of the TENEBRIONITEs, formed of the single genus (1) The underpart of the same thighs is also silky in the male Heliophili. (2) Catalogue, &c , Dej ., p. 65. (3) Dej., Catalogue, &c., p. 65.-Blap! tibidena, Schrenh., Synon. Insect., I, i, tab.l ii, 8. (4) Dej., Ibid.; Fisch., Entomog. Russ., II, xx, 1-5. (5) The Epitragi, by their jaws, which are armed on the inner side with a tooth, in a systematic arrangement, should be placed in this tribe; they would be removed from all the subgenera of which it is composed, by'their much larger mentum that covers the origin of the maxillz: but in a natural order, it appears to me they should be placed near Helops. Vot. HI.-3 H |