MICEOCYSTINA. ZOO 



oblique, rather broadly lunate ; peristome thin, columellar margin 

 broadly reflected, vertical for a short distance above, the salient 

 process closing the perforatioii of the shell. 



Major diam. 7|, min. 7, height 4i mm. 



Hab. Koudul Island, jSicobar Group ; north coast of Gi'eat 

 Nicobar. 



This is the largest species yet described from the Nicobar or 

 Andaman Islands. 



391. Microcystina waniefordi, Godivin- Austen {Nevill, MS.), Mol. 



hid. i, 1882, p. 13, pi. 3, ligs. 8, 8 o (shell and sculpture) ; ii, 1898, 

 p. 47 ; id. P. Z. S. 1895, p. 447. 



Shell obtectly perforate (almost imperforate), depressed, thin, 

 pohshed, smooth, with very fine, close, and regular, longitudinal, 

 microscopic striation, umber-brown ; spire low, conoidal, suture 

 shallow ; whorls 5, convex, the last rounded at periphery, convex 

 beneath ; aperture nearly vertical, lunate ; peristome thin, colu- 

 mellar margin oblique, reflected, and with an angular projection 

 which nearly closes the perforation. 



Major diam. 4, min. 3|, height 2 mm. 



Hah. Port Blair and the Brothers, Andaman Islands. 



'• Jaw very curved, central projection well developed. Animal 

 black, with well-developed right shell-lobe, and large lobe over the 

 mucous gland." (Godivin- Austen.) 



392. Microcystina harrietensis, Godtoin-Austen {Nevill, MS.), 31ol. 



Ind. i, 18b2, p. 13, pi. 3, tigs. 11, 11 a (shell and sculpture). 



Shell imperforate, subglobosely depressed, smooth, not highly 

 polished, with longitudinal, distinct, rather distant striation 

 throughout under the microscope, umber-brown ; spire conoidal, 

 convex at the sides, apex obtuse, suture impressed ; whorls 5, 

 convex, slightly increasing, the last not descending, rounded at 

 periphery and beneath ; aperture stvbvertical, lunate ; peristome 

 thin, reflected, with an angulate projecting process covering the 

 perforation of the shell. 



Major diam. 2-3, axis 1*3 mm. 



Hab. Mount Harriet, Port Blair, S. zVndaman Island. 



393. Microcystina stewarti, Blanford (stuarti, Godwin-Austen, 3IS.), 



P. Z. S. 1904, ii, p. 44(j, pi. 25, tig. 10 (shell). 



Shell imperforate or subperforate, convexly depressed, very thin, 

 smooth, highly polished, with faint transverse lines of growth and 

 very fine, parallel, not very close, longitudinal, microscopic striation 

 above and below, yellowish brown ; spire low, convexly conoid, 

 suture scarcely impressed ; whorls nearly 5, flatly convex above, 

 the last not descending, roimded at the periphery, convex below ; 

 aperture oblique, lunate ; peristome thin, columellar margin 



