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Show 1906.] COLEOPTERA OF THE GENUS SCIOBIUS. 239 of Curculionida3 from both Bothaville and Hoopstad, there was not a single Sciobius among them. Of the comparatively few species with whose habits I am acquainted, the majority feed on low trees and shrubs; and on the Natal coast brevicollis and bistrigicollis are among the commonest beetles to be obtained by general beating. On the other hand, the smallest species, and those with a predominance of bright green colouring, appear to prefer herbaceous plants and are generally obtained with the sweeping-net. The general type of colouring is black or reddish brown variegated with grey, whitish or yellowish scaling, which has a fairly constant tendency to form a denser lateral stripe, often accompanied by a transverse band across the summit of the elytral declivity. In only a few instances are bright colours to be found, and then they are of a green or golden-green hue. There can be little doubt that in every case the colouring of these insects will be found to have a simple procryptic significance. There is a well-marked sexual dimorphism in many of the species, so that in one or two cases the sexes have been described as distinct forms. But these sexual characters are often very different in the various species, and the only one which is constant throughout the genus (or, rather, throughout the 24 species of which both sexes are known) is the form of the last abdominal segment. This is always more acuminate in the $ a Q d is usually slightly convex in the middle; whereas in the S it is more broadly rounded apically and proportionately more transverse, and generally there is a more or less shallow central impression. Another common character is the greater curvature of the tibiae, especially the anterior pair, in the S • But in the case of obesus, dealbatus, opalinus, pollinosus, and marginatus, the tibiae are practically similar in the two sexes. In a few species, such as brevicollis, granosus, and pondo, this distinction is specially well-marked, the tibiae of the S being also broader and noticeably compressed. In the great majority of instances, however, the difference is comparatively slight. Homi presents a special feature in that the anterior tibiae of the S are distinctly sinuate internally. Another striking sexual character is to be found in the rostrum, in which the genae of the d are occasionally produced into long, recurved, horn-like processes. But this is only the case with granosus and cultratus. In bistrigicollis and dealbatus there is a similar production, only to a much less extent, and the process is not recurved. In cinereus, scapular is, griseus, and viridis the genae are only slightly more dilated in the o* than in the <? ; whereas in the remaining 16 species the sexes do not differ in this respect. As a rule, the shape of the prothorax is similar in the two sexes, but in brevicollis, bistrigicollis, barkeri, marginatus, pondo, and tottus this segment is distinctly shorter and more transverse in the £ ; in granosus its sides are more strongly rounded in the tf ', while in cultratus the central portion is more elevated and smoother in the £ than in the cS . In the majority of species the shape of the elytra varies considerably in |