78 HELICID^E. 



2. P. RINGENS (grinning). 



Ovate, rather solid, glossy, dark horn-colour ; ivhorls six 

 and a half ; mouth horseshoe-shaped, furnished with seven 

 or eight tooth-like processes which, as well as the reflected 

 lip, are often of a reddish tinge ; umbilicus small, but dis- 

 tinct. 



The name ringens, which signifies "grinning like a 

 dog," i.e. " showing its teeth," was of course suggested 

 by the appearance of the mouth, the denticular pro- 

 cesses of which are a safe mark of distinction from the 

 two following species. 



It lives among moss and dead leaves in moist situa- 

 tions in Scotland, the north of England, and Ireland 

 generally. 



Young specimens are furnished with internal septa, 

 which are visible from the outside, and are carinated. 



Var. pallida. Whitish. 



3. P. UMBILICATA (having an umbilicus). 



Sub- cylindrical, rather solid, glossy, semi-transparent, 

 pale horn-colour ; whorls six to seven ; mouth horseshoe- 

 shaped, with a broad strong white lip ; on the base of the 

 penultimate whorl there is sometimes a denticle ; umbilicus 

 small. 



This is a very abundant and common species 

 throughout the British Isles on stone walls and among 



