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Show 264 MR. M. JACOBY ON PHYTOPHAGOUS COLEOPTERA [Mar. 6, acute; antennae extending nearly to the apex of the elytra, black, all the joints, with the exception of the second, elongate, the third joint shorter than the fourth, terminal joint thinner and more cylindrical in shape than the others ; thorax about one-half broader than long, slightly constricted at the base, the angles tuberculiform, the sides nearly straight, the disc with a very deep and broad sulcus, metallic blue, the non-impressed parts very finely punctured, the anterior portion with another small depression; scutellum broad, metallic blue ; elytra finely and closely punctured, with traces of longitudinal sulci, flavous, the margins narrowly metallic blue ; below and the legs metallic blue. Hab. Natal. (Coll. Mr. Andrewes and m y own.) At first sight this species entirely resembles the type of the genus, S. viridicollis Jac. (Trans. Eut. Soc. Lond. 1895, p. 333), but may be at once distinguished by the colour of the antennae and that of the legs; but this is not the only difference. The male of the present insect differs from that of S. viridicollis in having the antennae longer and more robust, with the intermediate joints slightly dilated ; the thorax, instead of having two deep foveae, has a continued broad sulcus, nearly extending to the sides : in the female the antennaB are much shorter, very robust, and the thorax has two foveae as in the allied species; but in all the specimens the colour of the antennae and that of the legs agrees with the male of the insect described here, the general size is also rather larger. PLATYXANTHA BICINCTA, sp. n. (Plate XX. fig. 8.) Flavous, the head and thorax reddish fulvous, the latter impunctate, transversely sulcate; elytra extremely minutely punctured, flavous, a narrow transverse band at the base and another near the apex dark metallic blue. Length 4 millim. Head impunctate, frontal elevations very narrow, in the shape of a transverse ridge, clypeus strongly raised, narrowly triangular ; antennae extending to the middle of the elytra, flavous, the apical joint fuscous, the second joint small, the third and following joints equal, nearly subcylindrical ; thorax scarcely twice as broad as long, of equal^ width, the sides feebly rounded, the angles acute, slightly tuberculiform, the surface impunctate, deeply transversely sufcate, the sulcus interrupted at tbe middle, scutellum fulvous; elytra slightly wider at the base than the thorax, extremely finely punctured, flavous, the base with a narrow transverse band, extending to the margins, the latter and another band near the apex metallic dark blue ; below fulvous, legs flavous ; tibiae unarmed; the metatarsus of the posterior legs as long as the following joints together • anterior coxal cavities closed. Hab. Salisbury, Mashonaland (G. Marshall). A rather small species, possessing all the characters of the genus: it may be known by the colour of the antennae, which have only the last joint dark, and by the two blue transverse bands of the elvtra. |