104 HEL1CID&. 



Shell compressed, of equal convexity above and beneath, 

 extremely glossy, semitransparent, darkish horn-colour, with 

 regular, close-set, sharply-defined, curved, transverse striae, which 

 extend to the suture and impart to the shell a rayed appear- 

 ance ; the striation is similar but less distinct at the base 

 of the shell ; epidermis thin ; whorls 4-4!, convex, slightly 

 compressed near the suture, body whorl scarcely half the 

 size of the shell ; spire slightly produced, apex blunt ; suture 

 not very deep ; mouth forming about three-fourths of a circle, 

 occasionally provided internally with a thin white rib ; outer lip 

 very slightly oblique ; umbilicus small but deepish. 



Inhabits woods and hedgerows, among moss and 

 decayed leaves, at the roots of grass, and under stones 

 and fallen branches in most parts of Great Britain. 

 This pretty little shell may be distinguished from 

 Z. purus by its more glossy appearance, as well as by 

 its stronger striation and smaller umbilicus. 



Var. viridescenti-alba. Shell greenish white. Shropshire, 

 Co. Cork, Co. Tyrone, Aberdeen (J. G. J.), Belfast (Thompson), 

 B.C. Near Birmingham (G. Sherriff Tye), J.C. 



7. Z. NI'TIDUS,* MtJLLER. PL. VII. 



Body rather small, strongly truncate in front, slaty-black or 

 brown, tubercles flattish, round, large, black, placed rather 

 widely apart ; tentacles thick, upper pair blackish, moderately 

 diverging at their base, bulbs globular, lower pair much shorter 

 than the others, paler in colour, and considerably diverging ; 

 foot slightly truncated in front, narrow, and slightly keeled 

 behind. 



Shell subglobular, considerably more convex above than 

 beneath, moderately thin, glossy, semitransparent, brownish 

 horn-colour (much darker when the animal is within), with 

 numerous close-set, curved, transverse striae, which extend to 

 the suture, where they are puckered and more strongly defined ; 



* Shining. 



