OCR Text |
Show 532 INSECTA. CALLIDIUM, \Vhich is now divided into three. Those species, in which the head is at least as wide as the thorax and where the latter is almost cylindrical and simply dilated and rounded in the middle, compose the genus CERTALLUM of MM. Megerle and Dejean(!). Those, in which the head is narrowet· than the thorax, elevated, and almost globular, form that of CLITus, Fab. Finally those, in which the thorax, also wider than the head, is flattened and orbicular, have retained the generic appellation of CALLIDIUM. A species of this division, C. sanguineus; Cerambyx sanguineus, L.; Oliv., lb., 70, 1, about five lines in length, black, with villous elytra and thorax of a fino sanguineous-red, is very common in the wood-yards and even houses of Paris, in the spring. The C. arcuatus; Leptura arcuata, L.; Oliv., lb., 70, ii, 16, which is about half an inch long, of a deep black, with two bands on , the thorax, three arcuated streaks on the elytra, and some points on their base and extremity of a golden-yellow, is a Clitus. This insect also is very common. We will terminate this tribe with Insects, which, in rela. tion to their palpi, form of their head, thorax and elytra, as well as in their proportions, present remarkable exceptionsor anomalies. We will commence with those in which the form of the thorax is very analogous to that of the preceding ones, and par· ticularly of the Certalla. It is equal in width to the head, and to the base of the elytra, or scarcely narrower, and either al· most cylindrical, or rounded, or nearly orbicular, and wider near the middle in both cases. The last joint of the pal pi is sometimes attenuated near the end and terminated in a point, and sometimes truncated, thicker, and obconical, at the same extremity. All the thighs are clavate, and supported by an abrupt, slender and elongated pedicle. The elytra of the greater number are either very short or abruptly narrowed at but little distance from their base, and then become subulate. (1) Callidium ruficolle, 'f'ab.;-C. fugax, ejusd.; Callidium setigerum, Germ. COL~OPTERA. 533 In the first place we have those in which no such dissimilitudes are to be found, their forms and relative proportions being always the same as those of the elytra of the preceding Insects. The first genus 0BRIUM, Meg. Dej.-Callidium, Saperda, Fab. Is characterized as follows: the head rounded, and not prolonged anteriorly in the manner of a snout; palpi filiform, the last joint terminating in a point; antenn~ long and setaceous; thorax long, narrow, almost cylindrical, or forming a truncated oval(l ). The second genus RHINOTRAGus, Dalm.(2) Differs from the preceding one in the head, which is narrowed and prolonged anteriorly in the manner of a snout; in the palpi of which the last joint is rather thicker than the preceding ones, and truncated at the end; in the antenn~, shorter than the body, slightly dilated and somewhat serrated at the extremity; and in the almost orbicular thorax. These Insects are evidently allied to those of the following genus; the N ECYDALis, Lin. The only one of this tribe in which the elytra are either very short, and squamiform, or prolonged, as usual, to the extremity of the abdomen, but abruptly contracted a little beyond their origin, then much narrowed, and terminating in a point, or subulate. This is the only point in which these last mentioned Insects resemble the CEdemerre, with which Fabricius has arranged them. The last joint of the pal pi is a little longer, and almost obconical and compressed. Their abdomen is long, narrow, contracted, and as if pediculated at base. The wings are folded at their extremity. Those species in which the elytra are subulate will form a first subgenus, STENOPTERUS, Illig. From which we might separate various species, foreign to Europe, (1) See Catrlogue, &c., of Count Dejean, p. 110. (2) Dalm., Insect. Spec. Nov., p. 513. We may also refer to it the Stenopteri Juridu,, punctatua, albicans, of the Bntom. Bras. of Kliig. |