LAND SNAILSo 
161 
Vertigo alpestris —{the Alpine Whorl Shell) 
(PI. IX., fig. 88)—differs from the last species, 
and is regarded by many as a variety of it, in 
being more cylindrical, of a paler colour, slightly 
striated, and in the absence of any rib, either 
inside or outside, to the mouth. 
Messrs. Forbes and Hanley say, “ It may be 
taken in great numbers by laying a piece of old 
wood upon the grass at nightfall, and examining 
it in the morning.” 
It occurs in a few places in Cumberland, Lan¬ 
cashire, and Northumberland; at Over, Glou¬ 
cester, and among moss on the canal banks at 
Sharpness (Mr. J. Jones) ; and is sparingly dis¬ 
tributed in North and Central Europe. 
Vertigo antivertigo —{the Marsh Whorl Shell) 
(PI. X., fig. 103).—The shell of this species is 
dextral, and is not reversed, as in some others 
of the genus; it is of an oval form, thin, slightly 
polished, and of a brown colour; whorls five; 
the aperture is small, subtriangular, with a 
whitish margin, and provided with three unequal 
folds above on the pillar, and three on each side. 
A very appropriate specific name given to this 
snail was palustris , as denoting that it was an 
inhabitant of marshy places, about the roots of 
plants; it is also to be met with under stones 
on the banks of streams and lakes, even in 
elevated situations. Though an inhabitant of 
M 
