ZONITES. 35 



Helix nitens, Sheppard, Trans. Linn. Soc. vol. xiv. p. IGO. 

 „ foatida. Stark, Elem. Nat. Hist. vol. ii. p. 5.9. 

 „ luridu, Studer, Verz. Schweiz. Conch, (not synon.) fide Chaip. 

 ? „ tenera, Hartm. Neue Alpina, vol. i. p. 232. 

 Polita glabra. Held, in Isis, 1837, p. 619. 

 Helicella „ Beck, Index Moll. Miis. Christ. Frid. p. 6. 



„ alliaria. Beck, Index Moll. Mus. Christ. Frid. p. 7. 

 Zonites alliarius. Gray, Manual L. and F. W. Shells, p. 160, pi. 4, f. 39. — 

 Macgil. Moll. Aberd. p. 91. 



Shell rather small, convex yet depressed, highly polished, 

 thin, transparent, clear yellowish, or yellowish horn-colour, 

 changing into rather opaque white towards the middle 

 of the lower disk, almost smooth, or only faintly striated. 

 Spire very little raised. Volutions four, not convex but 

 deeply defined, not rapidly enlarging ; the last broad, 

 flattened, and not bending much forward. Aperture not 

 very oblique, crescent-shaped, rather broader than high, 

 about equal in width to half the total diameter. Peri- 

 stome thin, simple, not reflected. Base rounded at the 

 sides, umbilicus deep. 



Diameter about a quarter of an inch. It is smaller and 

 more convex than cellaria, with its aperture less obliquely 

 inclined, and its basal opacity less manifest. Its bright 

 clear and transparent colour distinguishes it from nitidula. 



The animal resembles cellaria and the rest of this sec- 

 tion in shape, but differs in colour, being of a general deep 

 violet or black hue, paler only on the sole. It is remark- 

 able for secreting a mucus that gives out a pungent 

 odour of garlic. It is universall}^ diffused through the 

 British Isles, living in very various localities, common 

 in gardens and greenhouses, and frequent under stones 

 on sandy dunes. It is found also at a considerable eleva- 

 tion on mountains, living under stones even upon their 

 summits. 



