498 MR. E. A. SMITH ON LAND-SHELLS [May 7, 



superne ad canalem suturalem carina lamelliformi munitus, lineis 

 incrementi tenuibus leviter obliquis sculptus ; aperiura oblique 

 circularis, intus cceruleo-alba ; peristoma duplicatum, margine 

 interiori leevi vix expanso, superne prope anfractum parum 

 profunde sinuato, externo angusle expanso, superne ala parva 

 leviter fornicata instructo. Operculum corneum, concentricum, 

 multispirale, utrinque concavum, extus lamellis brevibus striatis 

 obtectum. 

 Diam. max. 31 mill., min. 22, alt. 15, apert. diam. intern. 9. 

 Hab. Borneo (G. B. Sowerby). 



Shell discoidal, openly umbilicated, and clothed with a thin uni- 

 form yellowish-olivaceous epidermis. Beneath this it is of a dirty 

 or bluish-white tint. The spire is only slightly raised above the last 

 whorl. The whorls, about five in number, are convex and bordered 

 by a deep and broadish channel at the suture, the outer margin of 

 the canaliculation being produced into a thin lamellar ridge or keel ; 

 and outside this carina the whorls are a trifle depressed or excavated. 



Fig. 3. 



Ct/cloj)lionts (Myxostoma) hathyraphc. 



The sculpture consists merely of the lines of growth, which are fine 

 and somewhat oblique. The aperture is slopingly circular, bluish 

 white, and has a double lip. The inner edge is thicker than the 

 outer, and scarcely at all everted. The sinus is distinct, moderately 

 deep, and situated at the termination of the sutural canaliculation. 

 The outer rim is somewhat expanded but not reflexed, narrowest on 

 the left side where it touches the whorl, and thin and sharp at the 

 extreme edge. Above it is expanded in the form of a small wing, 

 which slightly arches over the sinus and has a tendency to 

 a deflection in front. 



This species in the nature of its operculum agrees with the genus 

 My&ostoma, which was founded by Troschel (' Zeitschrift fur Mala- 



