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Show 1877.] MR. G. P. ANGAS ON HELIX SEPULCHRALIS. 803 or whether all the Solomon-Island specimens show this obvious tint. Besides, the blue of the belly appears to be deeper, and some feathers have in certain lights a greenish shade. 11. Notes on the Helix sepulchralis of Ferussac and its Allies; with Descriptions of two Species. By G E O R G E F R E N CH A N G A S , C.M.Z.S., F.L.S., F.R.G.S., &c. [Eeceived October 26, 1877.] (Plate LXXX.) The confusion that appears to exist amongst conchologists with regard to the nomenclature of certain land-shells from the island of Madagascar (hitherto passing as varieties of Helix sepulchralis of Ferussac) has induced me to make a careful examination of this somewhat protean group of Snails. After having referred to all that authors have written concerning them, and inspected a very large series of specimens, I am of opinion that several species, each presenting certain constant and distinctive characters sufficient to justify their separation, have been mixed up under the general name of sepulchralis. Ferussac, in his 'Hist. Moll.,' first describes Helix sepulchralis, giving the diagnosis of the species as follows : - " H. testa orbiculato-convexa, subdepressa, late umbilicata, glabra, castanea, subtus albo zonata, apice alba; labro valde expanso, intus albo, margine refiexo." The type shell is figured by Ferussac on plate 75. fig. 1 ; and on plate 75 c there are given as varieties figs. 1-12. Pfeiffer, in the ' Monographia Heliceorum viventium,' also says Helix sepulchralis is "late umbilicata." Reeve, in the 'Conchologia Iconica,' describes tbe species as being broadly umbilicated, and on plate 39 of his Monograph of Helix gives three figures. The first of these, 147 a, represents the true sepulchralis; 147 b is a distinct shell, and has since been described and figured by Crosse in the ' Journal de Con-chyliologie' for 1869, p. 391, plate 12. fig. 3, under the name of Helix subsepulchralis; whilst 147 c I regard as a third species, for which I propose the name of Helix hova. Amongst the shells thus confused together under the general name of sepulchralis, there appear to me to be at least four separate species, all of which, though displaying, more or less, certain characters'which I regard as belonging to the group, are yet easily recognizable at once as being distinct. First comes the Helix sepulchralis proper (Plate L X X X . figs. 1, 2), the leading characters of which may be thus briefly noted. Shell double the size, or nearly so, of its allies; widely and perspectively umbilicated ; spire very slightly raised ; whorls with the concentric depression moderate, and carried through all the whorls to the apex; the upper surface of the body-whorl coarsely obliquely plicately malleated; colour either dark purplish chestnut, or pale olive-green inclining to violet near the apex, with occasionally a white band surrounding the umbilical region, but never banded above. |