156 HELICID^. 



rather close together, lower pair somewhat diverging \foot rather 

 narrow in front, broader towards the tail, which is triangular. 



Shell nearly cylindrical, somewhat solid, scarcely semitrans- 

 parent, slightly glossy, light brown or yellowish horn-colour, with 

 numerous fine, close-set, irregular striae in the line of growth ; 

 periphery rounded ; epidermis thin ; whorls 6-7, convex but 

 slightly compressed ; spire short, apex obtuse ; suture deepish ; 

 mouth forming about two-thirds of a roundish oval, often pro- 

 vided with a small denticle which is placed in or near the 

 centre of the base of the penultimate whorl ; outer lip rather 

 thin, slightly reflected, and furnished outside, at a short distance 

 from the margin, with a strong white rib ; itiner lip very thinly 

 spread on the base of the penultimate whorl ; iwibilicus narrow. 



Inhabits many parts of Great Britain, in the crevices 

 of rocks, under stones, and among moss and dead 

 leaves. It occurs most abundantly near the sea- 

 coast, in sandy pastures, at the roots of grass and 

 other plants. 



Like the last species it is ovoviviparous ; it breeds 

 during the months of July and August, and the eggs 

 are from three to seven in number. 



Var. I. bigraiiata (having two grains or tubercles), Ross- 

 massler.— Shell rather smaller and thicker, and having a tuber- 

 cular tooth or denticle on the inside of the outer Hp, in addition 

 to that on the base of the penultimate whorl. Bath (Clark), 

 Lulworth, Dorsetshire (J. G. J.), Oxfordshire (Whiteaves), 

 Weston-super-Mare (Norman), B.C, Lewes and Beachy Head 

 (R. R.). 



Var. 2. albijia, Menke. — Shell white. Somersetshire (Clark, 

 Norman, and J. G. J.), Oxfordshire (Whiteaves), B.C. 



GENUS VIL—VERTrGO* mUlLER. 



Body capable of being entirely contained within the shell ; 

 tentacles 2, tips very slightly swollen. 



Shell ovate, or somewhat cylindrical, or spindle-shaped, thin. 



A turning round. 



