- 144 LAND AND FRESH-WATER MOLLUSKS. 
The spire in old specimens is whitish, by 
exposure. ‘The snail in crawling carries its shell 
upright, and not inclined to one side, like the 
majority of the Helices. A peculiarity possessed 
by this snail is that of retaining the eggs in the 
interior of the shell (ovoviviparous) until they 
are hatched. Mr. J. G. Jeffreys has found the 
young under such circumstances, with a whorl 
and a half formed. 
Hewix pyamma—(the Piqmy Snail) (Pl. VIIL., 
fie. 71).—This beautiful tiny gem, so interesting 
from its minuteness, is no bigger than the head 
of a good-sized pin; and on account of its 
minute size, it is difficult to find; but the much- 
prized treasure is within the reach of all, and will 
be found by him who searches properly for it; for 
it is widely diffused throughout Britain. Firstly, 
then, to describe the object of our search, and 
then to direct attention to where it is likely to 
occur. 
The shell is nearly circular, with four convex 
whorls, of a pale brown colour, semi-transparent, 
and having a-silky lustre, slightly striated ; 
aperture crescent-shaped; umbilicus large. 
It differs from H. rupestris, its closest ally, 
in its much smaller size, finer texture and orna- 
mentation, lighter colour, fewer whorls, more 
depressed spire, and more open umbilicus. 
It is partial to shade and moisture, under 
