LAND SNAILS. | 105 
HELICELLA CELLARIA—(the Cellar Snail) (PI. 
VIL., fig. 63)—is one of our common shells, uni- 
versally distributed throughout Great Britain ; 
beneath stones, about walls, in gardens, and 
woods. It has a predilection for wet situations, 
and is not unfrequently found in damp cellars. 
It has been introduced into Portland, Maine, U.S., 
where it is rare, in cellars and gardens. 
The shell is flattened, with the spire very little 
raised ; the colour is a dirty yellow or pale horn, 
upper surface rather opaque, under surface 
clouded with opaque white, especially about the 
umbilicus, which is very large, and exposes the 
second whorl; the whorls are five or five and a 
half im number; the aperture is obliquely cres- 
cent-shaped, rather broaderthan high. It is the 
largest of the British species, having an average 
diameter of two-fifths to half an inch, but attain- 
ing even to three-fourths of an inch. 
The dental formula is +7737. ‘ The central 
plate is very long and narrow, with three teeth, 
occupying nearly the centre of the plate; the 
Kacegey ay | 
Fig. 19. 
first four laterals are irregular in shape, ap- 
parently bidentated ; the wncini are long, single, 
