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Show 1888.] MOLLUSCA F R O M B U R M A H . 243 oblique, semilunate; peristome strong; columellar margin very oblique. Size: ..aj. diam. 1225, min. 11*20, alt. axis 5'0, body-whorl 6*5 mm. This shell belongs to a group common in Arakan &c. (E. pansa, helicifera, ataranensis, mammillaris), but is of a more depressed form and larger in size, smooth below and well sculptured above ; E.falcata is a large representative of the group in the Khasi Hills. 10. HELIX (PLECTOPYLIS) PONSONBYI. Locality. Hlindet, Upper Burmah, 1500 feet. Shell sinistral, widely umbilicated, discoid, solid ; sculpture, wavy thread-like lines of growth; colour pale brown; spire flat, 2| whorls at apex slightly raised above the succeeding whorls ; suture very shallow; whorls 7, closely wound and flat; aperture very oblique, descending, horizontally ovate; peristome thickened, reflected, the margin connected by a well-developed ridge, and with slight notches at the inner angles. Size: maj. diam. 17*5, min. 14*0, alt. axis 5 m m. Palatal teeth 6, the 1st highest, long, thin, like a knife-edge, the 2nd and 3rd are short and rounded above, the 4th and 5th are united; the 6th, situated on the lower outer side of the body-whorl, is short, somewhat thickened and rounded on the free edge. The parietal vertical laminae are two in number ; the anterior situated about 10 millim. from the inner margin of the peristome. The anterior one is curved, solid, arched above, with two short buttresses above and below on the anterior side. The posterior one is obliquely set, is thin, and of nearly even height throughout. The horizontal parietal lamina is only present as a short and narrow ridge 3 millim. in length, situated just within the aperture, but not connected with the apertural ridge of the peristome ; a threadlike, free, narrow, horizontal lamina, commencing from below the posterior vertical lamina, extends forwards towards the aperture, gradually fining out but not extending to it. To the ordinary observer the sh"1' would ordy possess the one simple short ridge near the peristj.ne, all the other complicated structure being out of view so far back within the aperture. 11. HELIX (PLECTOPYLIS) PERARCTA, W. T. Blanford. Locality. Hlindet, 1200 feet. Size: maj. diam. 10*0, min. 8*0, alt. axis 3*5 mm. The type of this species came from near Ava. In this specimen the horizontal lamina is continuous to the aperture, in others it is sometimes undeveloped for a short distance (vide P. Z. S. 1874, pi. lxxiv. f. 4). 12. STREPTAXIS THEBAWI, n. sp. Locality. Pingoung, Shan Hills, 2500 feet. Shell ovately globose, umbilicated, somewhat solid; sculpture finely costulated throughout; colour white; spire conical, apex |