1S65,] Contributions to Indian Malacology. 71 



at the periphery, the keel vanishing near the mouth. Aperture lunate, 

 oblique, breadth more than double the height ; peristome thin, curved 

 forwards at the base ; margins distant, columellar oblique. 



Millem. inch. 



Major diameter, 11 0.44 



Minor ditto, 10 0.4 



Axis, 7J 0.3 



Aperture 5 \ millem. broad, 2 high. 



Habitat — Southern portion of the Arakan range of hills near 

 Bassein and Cape Negrais. 



This shell is distinguished from N. mamillaris by its non-acuminate 

 apex, higher spire and more convex base, and from N. helicifera by 

 the absence of the columellar lamina, of which no trace appears in 

 the present species. It appears to replace the last named shell in the 

 southern portion of the Arakan hills. It is scarce, and I have met 

 with but few specimens in good condition. I have never seen the 

 animal, which, however, is doubtless similar to those of the two preced- 

 ing species. 



Section Trocliomorplia. 



8. N. confi'nis, n. sp. 



Shell minutely perforated, trochiform, very thin, whitish horny, 

 smooth, shining. Spire conical, apex slightly obtuse;, suture scarcely 

 impressed. "Whorls 7, flatly convex, marked above with 4 or 5 spiral 

 ribs and fine oblique lines of growth ; the last sharply keeled, flatly 

 convex beneath, and very finely radiately striated. Aperture oblique? 

 subrhomboidal, twice as broad as high ; peristome thin, acute, straight ; 

 margins distant, columellar subvertical, briefly and triangularly reflexed. 



Millem. inch. 



Major diameter, 10J 0.42 



Minor ditto, 9J 0.38 



Axis, 7 0.28 



Aperture 5 millem. broad, 1\ high. 



Habitat — near Thayet Myo, on the borders of British Burma ; also 

 near Ava. 



A near ally of N. arx, Bens., from Tenasserim, which, however, 

 may easily be recognised by the concave sides of its spire. From other 



