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Show 432 INS~~CTA. tibire almost cylindrical, or in the fot·m of an elongated cone, and the spurs at their extremity ~fan equal size. . The sixth and last sectiOn of the ScarabreHles, that of the MELI· TOPHILI, is composed of Insects in which the body is depresstd, most commonly oval, brilliant, and without ho1·ns, and the thorax is trape. ziform, 01• nearly orbicular; an axillary part, in the gTeater number, occupies the space compl'ised between the posterior angles and the exterior of the base of the elytra. The anus is exposed. The sternum is ft·equently extended into a point or projecting horn. The · hooks of the tarsi are equal atld simple. The autennre consist of ten joints, the tht·ee last of which form a club, always foliaceous. The labrum and mandibles are concealed, laminifurm, flattened, and membranous, or nearly so. The maxill:;e tet·minate in a silky, peni· cilliform lobe without horny teeth. The mentum is commonly ovoid, truncated superiorly, or almost square, and the middle of the supe· rior margin more or less concave or emarginate. The ligula is not salient. From the anatomical observations of M. Leon Dufour on several of these Insects, we may conclude, that of all the Scarabreides their alimentary canal is the shortest. 'l'he external tunic of the chylific ventricle is usually covered with extremely small, superficial papillce, in the form of salient points. The inflation which terminates the small intestine is not cavernous, as in the Melolonthre. The copu· lating armature of the males also differs from that of the latter. Each testis consists of ten or twelve spermatic capsules. Their pe· culiar ducts do not unite in one common point to form the vas defe· rens, but communicate with each other in various ways. The num· ber of vesiculre seminales is from one to three pairs. The ejacu· lating canal is extremely tortuous, and becomes greatly inflated before it penetrates into the organ of copulation( I). The larvre live in rotten wood. The perfect Insect is found on flowers, and frequently on trunks of trees, that give out a fluid which they suck. This section is susceptible of being separated into three principal divisions, the first of which corresponds to the genus Trichius, Fab.; the second to that of Goliath, Lam.; and the third to Oetonia, Fab., but reduced and simplified by the abstraction of the second genus, as well as of Rutela and other analogous sections. The Melitophili of the two first divisions have no well mat·ked sternal projection; the lateral portion of the mesosternum, which we have designated by the term axillary-epimet·a of Audouin-is not (1) See Ann. des Sc. Nat., Ill, p. 235, and lV, p. 178. COLEOPTERA, 433 genera Jly visible above, ot· merely occupies a portion of the space rised between the posterior angles of the thorax and the exte-c~ m~ase of the elytra. The thorax does not widen from before postretor~ to 'r ly , as in the Cetonire. The outer side of the elytra is not abtly narrowed or unisinuate a little below the humeral angles, as .ru pt he latter Insects. A more ri. gorous c h aractcr, l1 0wcver, .t s, t h at :ere the labial palpi are inserted in late1·al foss.ulre of the anterior ~ ce of the mentum, so that they are entirely exposed, and that the ~des of this mentum jut beyond them, even at their origin, and \otect them behind. In the two first divisions these pal pi are in~ erted undet· the lateral margin of the mentum, or even in the margin, so that ,vhcn viewed from before the first joints are no~ per-ceptible. In the first-Trichides-the mentum is either isometrical, or longer than wide, and leaves the maxill:;e exposed. It comprises the TRICHius, Fa b.( 1) T. nobilis; Scarabceua nobilis, L.; Oliv., Col., I, 6, iii, 10. About an inch long; golden-green above; cuprcous with yellowish- grey hairs beneath. On umbelliferous plants. T. Jaaciatus; ScarabF£us fasdatus, L.; Oliv.~ lb., i~, 84. Rather smaller; black, w.i.th scattered yellow hatrs; elytra yellow with three transverse, black bands, interrupted at the suture. Very common in spring on flowers. T. eremita; Scarab. eremita, L.; Oliv., lb., iii, 17. Large, and of a brown-black; ma1·gin of the head turned up; three sulci on the thorax.-On the trunk of old trees, in the interior of which resides the larva. The female of the T. llemipterus-ScarabF£us emipteru3, L., Oliv., I b., IX,· 83, xi, I OS-and those of some other species of North America are remarkable for the horny ovipositor at the posterior extremity of their abdomen, by which they effect a lodgement for their ova. These species are generally found on the .groun~, where t~~y move very slowly. The last joint of the1r max1llary pa~pt.~s proportionably shorter and thicker than that of other Tnchu; the length of the first of the posterior tarsi also appe~rs ~o me to be considerably greater than the follow_ing one, whlle m the other Trichii it is not so(2). · (I) Messrs Lepeletier and Sertille, Encyc. Method., have established several new diviaions, some of which, it appears to us, should fot·m separate subgenera. (2) See Schamherr, Synon. Insect., I, iii, p. 99. VoL. 111.-3 E |