78 LAND AND FRESH-WATER SHELLS. 



well-defined but not deep ; mouth an elongated oval, about frds 

 of the total height of the shell. Length -|fths inch. Marshes 

 and ditch-banks. Moderately common. S. pfeifferi.^ 



(d) Shell small, oval, somewhat like that of L. truncatula, light 

 horn-coloured ; whorls four, convex : suture deepish ; spire pro- 

 duced, with a blunt apex ; mouth oval, about the same length as 

 the spire. Distinguished from L. truncatula by having no reflected 

 lip on the columella. Length |th inch. Edges of diiches near 

 the coast, and on sand-dunes near the sea. Rare. S. oblonga. 



21. Vitrina. Shell subglobular, thin, flattened , mouth large 

 and semilunar ; umbilicus wanting. 



(a) Shell depressed, thin, glossy, glassy-green ; whorls three to foui\ 

 the body whorl being very large ; spire very short ; mouth large, 

 somewhat oval. Height y^th inch. Among moss and dead leaves 

 in woods and hedge-banks. Moderately common. V.peUucida.^ 



22. Hyalinia (Zonites). Shell orbicular, depressed, umbili- 

 cated ; inouth obliquely crescent-shaped. 



(a) Shell slightly convex above, glossy, striae demi-effaced, 

 reddish above, whitish below, especially round the umbilicus; 

 whorls six to seven, the last whorl slightly dilated towards the 

 aperture ; umbilicus largish ; mouth oval, very oblique. Diameter 

 | to fths inch. Very local. Found only, as yet, at Guernsey, Tor- 

 quay, Falmouth, Bristol and Isle worth, London. H. lucida. 



(l>) Shell dirty yellow or pale horn-coloured, glossy, under 

 surface white, especially about the umbilicus; whorls five to six; 

 spire very flat; umbilicus rather open; mouth crescent-shaped. 

 Diameter ^ inch. Under stones in fields and woods, about walls 

 in gardens. Common. H. cellaria.^ 



50 v. ventricosa, spire more elevated, body-whorl convex, aperture large, less 

 elevated, a little more than half the total height of the shell ; v. propinqua, 

 shell elongated, ventricose, body-whorl very large, spire short, aperture large, 

 oval ; v. data, shell very slender, spire long and very tortuous, body-whorl 

 very contracted at its origin, aperture oval and scarcely one half of the total 

 height of the shell ; v. virescens, greenish, spire elongated, suture deep. (This 

 is regarded by some as a variety of S. elegans and not as a distinct species.) 



51 v. dillivynii, nearly globular, last whorl very convex, spire more prominent ; 

 v. depressiuscula, rather oval, flatter on both sides, spire scarcely raised. 



52 v. complanata, smaller, spire flatter ; v. compacta, body-whorl less swollen, 

 not so white beneath, more compact and convex. 



