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Show 444 INSECTA. abundant in these Heteromera than in the following ones, which ena~les t.hem, even ":hen transfixed and confined with a pin, to hve SIX months wtthout food, a fact I have witnessed i A . n an k1s. Our first division of this family, which in the LinnlEan sys· tern forms the genus TENEBRio, is founded on the presence or absence of wings. Of those which are deprived of these organs, and in which th~ elytra are ge.nerally soldered, some have the palpi almost fihform, or termmated by a moderately dilated joint, and do not form a distinctly securiform or triangular club. They will compose a first tribe, that of the PIMELIARIJE, so named from the genus PIMELIA, Fab., Which is the most numerous of the whole. Sometimes the mentum is more or less cordiform, the superior margin either emarginated in the middle, and divided as it were into two short and rounded lobes, or broadly emarginated or widened. Here, the two last joints of the antennre, or the tenth ot· eleventh always di~dtinct, sometimes unite to form an ovoid or pyriform body: or are eVl ently separated from each other. The superior margin of the mentum is rounded and emarginated in the middle, or as if divided into two festoons. ~hes~ have th~ anterior margin of the head almost straight or ~roJectmg but shghtly in the middle, without a profound emargina· t10n f~r the re~eption of the mentum, and its lateral margin simply and shghtly dilated above the insertion of the antennre; the head does not seem to be sensibly narrowed behind, nor widened and trun· cated before. The thorax is not cordiform, deeply emarginated before and truncated posteriorly. From these last, we may separate those in which the anteriormar· gin of the head is straight, or nearly so, without any angular or dentiform dilatation in the middle, in which the almost square and moderate sized labrum is entirely exposed, the thorax is transversal, and the abdomen extremely voluminous and inflated. Those, in which the body is more or less ovoid or oval, the thorax narrower than the abdomen even at base, generally convex, without acu~e prolongations at the posterior angles, and without a posterior proJection to the pra:sternum, compose the subgenus properly called COLEOPTERA. 445 PrMELIA-Tenebrio, Lin. These I!eteromera are proper to the countries situated round tl • lC basin of the Mediterranean, to western and southern Asia, and to Africa. They are not found in India, or at least none have as yet b~en discovered there. Some species, usually more elongated, have the mentum exposed and the an ten~~. slight] y and insensibly enlarged at the extremity~ the three last JOints .do ~ot form a club, divided into two equal portions, the last of which IS composed of the tenth and last joint confounded together. In some of these, the abdomen is proportionally wider and more voluminous, and the legs are less elongated; the anterior tibire are in the form of a reversed triangle, elongated, and have the exterior angle of their extremity prolonged; the spurs are stout and the tarsi short. M. Fischer-Entomog. Russ. lmp.-has divided them into three genera, Pimelia, Platyopus and Dieaia, but their characters, being only founded on the greater or less projection of the last joint of the antennre and the dentations of the anterior tibire, do not appear to us sufficiently determinate. The eleventh and last joint of the antenore is most distinct in the Diesire. The anterior tibire are much dentated exteriorly in Platyopa, where the thorax forms a transversal square, the base of the elytra is straight, and the exterior angles or the shoulders slightly project. Among the Pimelire, properly so called of this author, or those in which the eleventh and last joint of the antennre unites, or is almost confounded with the preceding one, where the thorax is almost semilunar and convex, and the abdomen nearly ovoid or globular, is placed the P. 2-punctata, Fab.; Oliv., Col., III, 59, i, 1. Length eight lines; glossy-black; thorax granulated, with two large punctures in the middle, united in some individuals in a transverse line; elytra granulated, each with four elevated lines, the lateral carina included, not visibly dentated, of which the two inner ones are shorter; suture elevated. Common on the shores of the Mediterranean. The Tenebrio muricatus, L., is a different species-Schrenh., Synon. Insect, I, tab. III, 9. P. coronata, Oliv., lb., II, 17. Fifteen lines in length; blackish; covered with reddish-brown hairs; a range of posteriorly curved spines on the lateral carina of each elytron. M. Payraudeau has discovered in Corsica a new spcciesPayraudii- allied to the first, but with a more elongated abdo- |