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Show 1891.] LAND-SHELLS FROM BORNEO. 33 It would be difficult to select two shells differing so much in form as D. hugonis and D. nasuta; any classification based on shell-characters would place them widely apart, yet the animals as regards their structure are closely allied. This points to a long occupation of this island by this group of land-shells. DYAKIA MOLUENSIS, n. sp. (Plate II. fig. 6.) Shell sinistral, depressedly pyramidal, not perforate, solid, rounded below, sharply keeled ; sculpture, irregular furrowing, crossed by rough transverse curvilinear and broken granulation ; colour dark chestnut-brown, with a lemon-yellow narrow line on the periphery and also running with the suture, a circle of same colour around the umbilicus ; spire low, sides flat; apex blunt; suture linear ; whorls 5, gradually increasing, flat-sided; aperture semi-lunate, very oblique; peristome thickened below, with a slightly sinuate margin above ; columellar margin oblique. Size: maj. diam. 28*0, min. 24*8; alt. axis 9'3 millim. Hab. Molu Hills (A. Everett). Only one specimen was sent home of this very pretty shell, which is somewhat like the dextral H. albula from Moti Island, one of the Ternate group. EVERETTIA, subgen. nov. (Plate III.) (Type, Macrochlamys jucunda.) The animal from a spirit-specimen is pale ochre in colour, with jet-black tentacles and a black band on either side of the neck from the base of the tentacles running backwards. The pallial margin (fig. 5) is broad, the foot below with a central ambulatory area. The mucous gland (fig. 5 a) is large, and in life the extremity of the foot is apparently much pointed and overhanging. There are no linguiform shell-lobes either on the right or left side, but on the latter the lobe is a simple band turned back over the edge of the peristome ; both the right and left neck-lobes are very small. The generative organs (fig. 6) are very peculiar and unlike those of any species I have examined or that I find figured by Professor Semper. The principal difference lies in the amatorial organ or dart-sac ; this is cylindrical below as in other genera, but at the inner extremity terminates in a fringe of very numerous accessory glands (fig. 6 a), very nearly equal in length to the solid fleshy lower portion. These fringe-like glands are finely pointed and lie buried in a mass of mucous glands having a segmented structure, each separate lobe being associated with one of the accessory glands. The lower end is armed with a stout and solid calcareous dart (Liebespiel), having a conical attachment to the muscular portion (fig. 6 b). The penis has no kale-sac. The albumen-gland is very large. The odontophore :-The rows of teeth, about 90, gradually decrease to the outer margin, the formula being 30. 26. L 26, 30. 56. 1. 56. P R O C . Z O O L . Soc. -1891, No. III. 3 |