110 HELICIDiE. 



five, rather quickly enlarging ; the penult more convex 

 than the preceding, and peculiarly large in proportion, 

 being almost equal to the length of the aperture, which 

 latter occupies nearly one-third of the shell ; apex obtuse. 

 Mouth somewhat trigonally subcordate, the outer lip being- 

 indented by an external sinus which runs parallel to the 

 spire ; with seven deeply seated distinct teeth, and usually 

 two additional denticles, thus distributed : three parietal 

 (or the upper part of the inner lip), three columellar, and 

 three palatal (or on the outer lip), of which the upper 

 palatal, which lies between the indentation and the poste- 

 rior corner, and the lower parietal one are scarcely per- 

 ceptible ; the lower columellar one, which is exactly in 

 the centre of the anterior corner, is likewise smaller than 

 the two above it ; the palatal teeth are sublamellar. 

 Peristome slightly expanded, whitish, a little behind which 

 is a broad but rather obscure rib. Base of the aperture 

 produced and angular. 



Animal blackish-grey ; lower tentacles nearly obsolete. 



This species was communicated to Dr. Leach as British 

 by Mr. J. E. Gray, who found it on Wimbledon Common, 

 near London, in 1817. It lives in or near marshy places. 

 It is local, but has a wide range. South Wales, on the 

 water flag in marshy ground near Swansea ; at Bristol 

 and Bath under ash boughs that have lain long on the 

 ground (Jeffreys) ; Devon (T. Hincks) ; Northumberland 

 (Alder) ; Ayrshire (W. Thompson) ; in localities, both 

 south and north, in Ireland (W.Thompson). 



