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Show 398 INSECTA. Our second tribe or the SPIIlERIDIOTA," consists of terres. trial Palpicornes, with tarsi composed of five very distinct joints, the first of which is at least as long as the second. The maxillary palpi are somewhat shorter than the antennm with the third joint longer, inflated and in the form of are: versed cone. The maxillary lobes are membranous. The body is nearly hemispherical, the posterior extremity of the prrosternum is prolonged into a point, and the tibiro are spinous '• those that are anterior are palmate.d or digitated in the large species. The antennro always consist of nine joints, or of eight, if the last be considered as an appendage of the penultimate(l ). These Insects are small, and inhabit cow-dung and other excrementitious matters ; certain species are found near the shores of rivers, &c. They compose the genuR SPIIJERIDIUM, Fab. From which, however, we must separate several species, a division already effected by Olivier. Dr Leach only considers as such those in which the anterior tarsi of the males are dilated. Such is S. 4-maculatum; Dermestes scarabreoides, L.; Oliv., Col. II, 15, 1 and 3, II, 11. It is of a shining black and smooth; the scutellum is ~longated, and the legs are very spinous; a blood· red spot at the base of each elytron~ and their extremity reddish. In some individuals these spots diminish or disappear. The species, in which the tarsi are similar in both sexes, and whose antenna} club is closely imbricated, compose the genus Cer· cydion(2) of Leach. The Spha:!ridia might be divided int~ ~everal other sections hy characters drawn from the form of the tlbi<e, and the disposition ~f their spines or dentations, a division which. would facilitate the study of the species, that seem to have been 1mpro· perly multiplied(3). ( 1) Sec Elatcr and several other genera of the Coleoptera. (2) The Spha:ridia unipunctatum, melanoceplwlum, &c.; Zool., Miscell., Jll, 'P· 95. . (3) For the other species, see Olivier, Schrenherr, Gyllenhal, DeJean, Stc. COLEOI>TERA. 399 FAMILY VI. LAMELLICORNES. In our sixth and last family of pentamerous Coleoptera, we find the antennre inserted into a deep fossula under the lateral margin of the head ; they are always short, usuaiJy consist of nine or ten joints, and are always terminated in a c1ub usually composed of the three last, which are lamellar, sometimes fiabelliform or disposed like the leaves of a book, opening and closing in a similar way, sometimes concentrically contorted and fitting in each other, the first or inferior then being semiinfundibuliform and receiving the others, and sometimes arranged perpendicular to the axis and forming a sort of comb. The body is generally ovoid or oval, and thick. The exterior side of the two anterior tibire is dentated, and the joints of the tarsi, with the exception of those of some males, are entire and without brush or pellet beneath. The anterior extremity of the l~ead most commonly projects or is dilated in the manner of an ~pi~toma. The m~nt~m is usually large, covers the ligula or 1s mcorporated wtth tt, and bears the palpi. The mandibles of several are membranous, a character observed in no other coleopterous Insects. The males frequently differ from the females, either by prominences on the thorax or head in the form of horns or tuber-cles, or by the largeness of their mandibles. . This family is very numerous, and with respect to the s1ze of the body, the variety of forms exhibited in the he~d and thorax, sexually considered, is one of the most beauttfu~ of the order, and frequently also as regards the species, whtch in their perfect state live upon vegetable substan~~s, by the splendour of the metallic colours with which they are ornamented. Most of the other species, however, feeding on decomposed vegetable aliment, such as dung, tan, or excrementitious matters are usually of one uniform black or brown hue. Some of th~ Coprophagi, however, · do not yield even |