74 HELICID^. 



23. H. LAPICIDA (stone-cutter). 



Circular, compressed, dark rufous brown, dull, semi- 

 transparent ; whorls five ; mouth obliquely oval, surrounded 

 by a strong white reflected rim ; very strongly carinated ; 

 umbilicus large. 



This strikingly formed shell is found in many parts 

 of England, rarely in Scotland and Wales, and not at 

 all in Ireland. It occurs chiefly in calcareous districts, 

 but not exclusively; it is fairly common at Maiden- 

 head (Berks), where the soil is gravelly, and at other 

 places. 



The name " stone-cutter " is due to its supposed 

 habit of boring into rocks. This idea is, of course, 

 erroneous, but it does ensconce itself in crevices of 

 rocks, whence it emerges after rain. 



Var. I. albina. White. 



Var. II. minor. Smaller and darker. 



24. H. OBVOLTJTA (wrapped up). 



Circular, flat above, compressed below, rather solid, 

 opaque, reddish brown, hispid ; whorls six and a half, 

 cylindrical ; mouth triangular, surrounded by a strong 

 pinkish white rim with three tooth-like protuberances ; 

 umbilicus large. 



This peculiar shell is only found in the neighbour- 

 hood of Ditcham Wood, Hants, where it is not un- 



