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Show 804 MR. G. F. ANGAS ON HELIX SEPULCHRALIS. [NOV. 20, Secondly, Helix subsepulchralis, Crosse (Plate LXXX. fig. 3.). Shell much smaller and more solid ; spire conical; whorls with the concentric depression and coarse plication absent; colour dark chestnut, with a narrow white band at the periphery and a broader one at the base; umbilicus more contracted, and non-perspective ; umbilical region invariably of a dark colour ; whilst the brown colouring shows on the interior of the lip. This is the shell figured by Reeve as H. sepulchralis, var. b. Thirdly, I will briefly diagnose the shell figured as var. c. This appears, ou the examination of many specimens, quite distinct from the H. subsepulchralis of Crosse. The shell is about the same size, but less conical; the umbilicus is more contracted ; there is a faint development of the depression on the upper part of the last whorl ; the painting invariably consists of three broad chestnut zones on a pale yellowish-olive ground ; and the umbilical region is constantly of a light colour. For this species I propose the name of H. hova. Fourthly comes another shell, equally distinct, somewhat larger than the last two, but never attaining the size of the true sepulchralis, from which it differs also in form, being less flattened and more compact ; it wants the oblique plications, but has the concentric depression strongly developed, the lower edge of it being bounded by a prominent elevated keel; the base is very tumid in front, and forms a kind of abrupt carina bordering the pinched and contracted umbilicus. The colouring varies from dark chocolate-brown to pale green, banded with brown zones, whilst the umbilicus is almost invariably encircled by a light or dark band, sometimes by both. One marked character of this species is the freckled, diaphanous, more or less zigzag ornamentation of the epidermis, which gives to the shell a beautiful appearance, and is never discernible in H. sepulchralis. The species, of which there is a bad figure in Ferussac (pl. 75 c. figs. 6, 7), I propose to call Helix sakalava. HELIX HOVA, n. sp. (Plate LXXX. figs. 4, 5.) Shell moderately umbilicated, depressedly conical, rather solid, under the lens extremely finely shagreened, greenish yellow with three broad chestnut bands; whorls 4\, rather convex, the depression on the upper surface of the last whorl very slight; base rounded, with a moderate excavation round the umbilicus, which is somewhat contracted and non-perspective; aperture oblique, quadrately ovate, white within; outer lip moderately expanded and reflexed, pure white ; margin joined by a thick white callus. D k m . maj. 1 in. 5 lines, min. 1 in., alt. 10 lines. Hab. Madagascar. HELIX SAKALAVA, n. sp. (Plate LXXX. figs. 6-11.) Shell umbilicated, orbicular, moderately solid, very minutely irregularly granulated above and below, chestnut, with a pale band surrounding the umbilical region, and more or less freckled throughout with angular or zigzag ochraceous diaphanous markings ; spire verv slightly raised, apex obtuse ; whorls 4|, rapidly increasing, the last |