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Show 278 MR. E. A. SMITH ON SHELLS FROM [Feb. 15, G. hraussianum, Reeve (non Pfr.), Con. Ic. fig. 52. Var. =C. lineatum, Pfr. Con.-Cab. pi. 45. f. 3-4; Reeve, Con. Ic. f. 46? Hab. Between Lake Nyassa and the east coast (Thomson). The shells from the above locality differ in some respects from the typical form of this species, yet scarcely sufficiently and persistently to enable me to describe them as distinct. The main difference is that of form and in the size of the aperture. In the smallness of the latter, four of them correspond with what I believe is only a variety of this species, viz. G. lineatum of Pfeiffer. Two others are more depressed, and have the last whorl, umbilicus, and aperture unusually large. It may be as well to point out the fact (which as far as I know, has not been previously noticed) that the true G. kraussianum of Pfeiffer is a very distinct species from that which appears as such in the monograph by Reeve, who in its stead merely figures (pi. ix. fig. 52) a second example of the present species, which he correctly delineates on the previous plate (fig. 41). The shell represented by him (fig. 46) as C. lineatum is not the type described by Pfeiffer, which is accurately depicted by the latter author in the ' Conchylien- Cabinet.' I may also take this opportunity of pointing out that the C. goudotianum of Sowerbyisa very distinct species from that figured by Pfeiffer (Conch.-Cab. pi. 13. figs. 8-10) under that name; also Reeve's figure (no. 42 a) correctly delineates the original type of the same species, but figure 42 b merely represents a smooth variety of the C. insulare. Although G. goudotianum is stated by the describer to have been collected in Natal by Dr. Krauss, I am of opinion that it will eventually prove to be a Madagascar species. In the expansion of the lip, its tout ensemble, and the presence of a colour band within the umbilicus (a feature not met with in species of this genus from South Africa, and which occurs in some from Madagascar and also in several species of Helix from that island) it calls to mind certain forms from the latter locality. The name (insulare) of this species is an unfortunate one; but until it is proved tbat it is without doubt distinct from the old C. liyatum it may be desirable to retain it. 3. HELIX (NANINA?) NYASSANA. (Plate XXXII. figs. 2-2 b.) Shell narrowly umbilicated, thin, depressed, keeled, rather glossy brownish horn-colour ; spire shortly conical. Whorls 5g, moderately convex, impressed beneath the suture, and depressed or shallowly channelled at the lower part immediately above the suture. Sculpture consisting of distinct and somewhat prominent lines of growth, crossed with close concentric microscopic striae; last whorl large, keeled and angled above the middle, convex beneath ; keel not acute; groove just above it distinct but not deep. Aperture obliquely lunate. Peristome thin, only expanded slightly over the umbilicus. Greatest diameter 25 millims., smallest 21; height 13; aperture 10 long, 13 broad. Hab. Between Lake Nyassa and the east coast (Thomson). The spiral sculpture which adorns this very interesting shell is |