CLAUS1LIA. 53 



in the north of England. It shows a great partiality to 

 beech woods, living among the decayed leaves of that 

 tree, and may sometimes be found on the trunk of the 

 tree itself. 



C. BIPLICATA. Montagu. PL VI, fig. 28. 



Shell ventricose, dark greyish brown, with regular longitudinal 

 striae ; aperture with two plates. 



Clausilia ventricosa, Jeff., 8fc. 



The regular raised striae at once distinguishes this 

 shell from the former, which it most nearly resembles 

 in other particulars. The spire consists of from ten to 

 twelve depressed, convex, but well-defined volutions ; 

 aperture sub-pyriform, with two plates, and sometimes 

 one or two additional denticles. It is about two thirds 

 or three quarters of an inch in length. 



Hob. This beautiful Clausilia is confined to the 

 south of England, inhabiting woods and hedges near 

 London ; it has also been found at Bristol. It is prob- 

 ably confined to the chalk districts. By no means 

 common. 



C. PLICATULA. Draparnaud. PL VI, fig. 29. 



Shell ventricose, thin, opaque ; with regular longitudinal raised 

 striae ; aperture containing four or five plates. 



Clausilia Rolphii, Gray. 



This rare Clausilia may be distinguished from bipli- 

 cata by its reddish chocolate brown colour, and by the 

 plates within the aperture. The costella striae are fine 

 and only slightly raised. Whorls ten to twelve, moder- 

 ately well defined, but not particularly convex. From 

 three-fifths to three quarters of an inch in length. 

 Animal dark grey, upper tentacles thick and clavate. 



Hob. First discovered by Rolph, in Charlton 

 Wood, Kent. It has since been found in other locali- 

 ties in Kent; also near Hastings, in Hampshire, Dove- 

 dale, in the Marsh, Gloucestershire, and Birdlip to 

 Cooper's Hill, near Cheltenham. It prefers damp 

 situations at the root of Mercurialis perennis, saxi- 

 fraga oppositifolia and other plants, on a chalky soil. 



