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Show 502 INSECTA. Some others, also inhabiting the same country, arranged by Schrenherr in the genus Polydrosus sericeus, Gyll., micana, be. tuhe, &c.--although small are not less attractive by their goldeD or silvery-green colour. In .some the mandible.s of the males are nan·ow, pointed, and project forwards. Th1s character is common to species foreign to Europe. The subgenus LEPTosoMus, Schrenh. Although formed of a single species-Curc_ulio acur:'inatua, ~ab. Oliv.-presents such isolated charactet·s, that ~t may st1ll be retame.d as a subgenus. The head is elongat~d p~stenorly and the sno.ut 1s very shot·t. The thorax is almost cylmdncal. The elytra termlllate in the manner of diverging spines. The antennce are short. We now pass to another subgenus, that of LEPTOOERUS, Wh. h d'ffers from the first in the two anterior legs, which are lC 1 d 'b' lat·ger than the following one, with the thick thighs, arcuate t1 1re, and the tarsi f1·equently dilated and ciliated. The antenn~ are usually long and slender. The thorax is almost globular or triangular. The abdomen is hardly wider than the thorax. These Insects are most abundant in Brazil, and several analogous spect· es are found in the Isle of France, or that of Bourbon. Others inhabit Africa(l). A fourth subgenus, that of PHYLLOBIUS, Will include other Brevirostres of the same division, also fu~· nished with wings, but in which the lateral sulci of the probosc~s are stt·aight, short, and even consist of a simple fossul~. To this we um· te van·o u.s genera of M • Schrenherr-h1s Phyllobzus, Macro· rynus, Myllocerus, Cyphicerus, .!lmblirldnus and Phytoscapus. (1) The genera Prostomus, Leptocerus, Cr a t opus, Le'~:'r~ rO:'rT IUS ' Il. adromerus, Hyb-Sonotus of Scha:nherr. The Ilybsonotes have t l1 e b o cl Y P1· o Po rttOnally no.rrhow er, and mo' re elongated; the proboscis almost as long as t h e h ead an d thor.· axI; t eT ahne· tennal sulci almost straight, but oblique, and the thorax lobate t~ter~ortyJoint of Leptoceri are distinguished fr·om all the others, by the length 0 t lde Irs h d· in the antenncc, the end of whr. ch when thrown b ack ext enus beyon tT 1le Ceara t'o pi the other genera it extends to but little, if at all beyond the .eyesd. f ~~e Indian . f B ·b nd some other 1slan s 0 are peculH\1' to the Isles o France, out on, a f versed Ocean. Their thorax is trapezor. dal, and ther· r a bdo men 'n the form o are L • d on males only, . triangle. The genus Prostomus has, perhaps, been estabhshe their mandibles being sometimes larger than those of the females. COLEOPTERA. 503 Those Brevirostres, in which the penultimate joint of the tarsi is bilobate, but that are apterous .and almost always destitute of a scutellum, will form other subgenet·a, viz. 0THIORHYNouus and· 0MIAS . ' in whish the antenna! sulc1 at·e straight; and PAOHYRHYxouus, PsA-LIDIU. M, 'fl:IYLACITES, and SvzYGOPs, in which those sulci a1·e curved. The Othiorhynci are distinguished from Omias by the auricular dilatation of the lateral and infel'ior portion of the proboscis, which gives the insertion to the antenn~; the Syzygops, or Cyclops of Dejean, by theit· eyes, almost united superiorly; the Psalidia by their salient and arcuated or crescent-shaped mandibles. The Thylacites are removed from the Pachyrhynci by their attenuated antennre, as long or nearly as long as the thorax, whilst hct·e they are thick and much shorter. The abdomen also is ventricose. To Omias( 1) and Thylacites(2) we unite several of the genet·a of Schcenherr. We may retain that of HYPHANTus, closely related to Othiorhynchus(3), but distinguished from it by the thorax, w.hich, compared to the abdomen, is very large and almost globular. Our second general division of the genus Curculio of Fabricius difl'et·s from the first in the narrowing of the mentum, which, not occupying the whole width of the buccal cavity, leaves the jaws exposed on each side, and in the mandibles that are evidently dentated. The club of the antennce is frequently formed by the five or six last joints. Some have scarcely more than two teeth in the mandibles. Their labial palpi are distinct. The club of the antenn::e, which is tolerably abrupt, only commences at the eighth or ninth joint, and is not elongated and fusiform. The body, although frequently oblong, is not of the same figure. Some are apterous, and their tarsi are destitute of pellets. Their penultimate joint is slightly bilobate. Such is the subgenus MYNIOPs, Schrenherr, to which may be united his Rhytir1'ltinus. · In others, also apterous, the under part of the tarsi, as in mos.t of the Rhynchophora, is furnished with pellets, and the penultimate joint is strongly bilobate. They form the subgenus LIPARus, which will also comprise various other genera of the same author( 4). Those which are winged may form two other subgenera, viz. HvPERA, Germ.,-Phytonomus, Coniatus, Schrenh., where the tibire have (1) The genera Peritelus, Pracltyphlreus, Episomus, Pholicodes, Ptocltus, Stomo-du, Sciobius, Cosmorhinus, Eremnus. (2) The Lioplllmus, Barynotus, Brachyderes, Herpisticu1 . (3) To this genus add the genera Tylodera and Elytrodon. (4) Molyte.rJ, Plinthus, Hypporhinu1, Epirhynchus, Geopltilu1. |