98 PULMONIFERA.—LIMACID&. 
Slugs proper are widely distributed, species being 
found in various parts of both hemispheres; but 
the temperate regions of the northern hemisphere 
are principally troubled with them. The common 
Grey Slug (Limazx agrestis) commits great ravages 
every year in our fields and gardens, notwith- 
standing the number of birds which make this 
species their prey; and various means have been 
devised to get rid of the pest, or at least to diminish 
its intensity. Quicklime, soot, coal-ashes, and 
saw-dust, are in turn sprinkled on the ground 
around tender plants ; but the effects of these and 
similar substances depend upon their dryness, and 
the inability of the Slug to crawl upon powdery 
substances. The first shower of rain, however, and. 
even the dews of night, break the spell. 
This species varies much in size and colour, 
being by turns white, pale reddish-grey, and nearly 
black ; but it may be easily distinguished by its 
body being furrowed with interrupted lines, with 
a short keel, which is always placed obliquely. 
The mantle is comparatively large, marked with 
circular lines; the enclosed shell is very minute, 
thick, hard, and irregular. 
The Grey Slug is very prolific, continuing to lay 
its groups of eggs from April to the end of No- 
vember, and depositing from thirty to seventy eggs 
at each time. ‘The young increase in size rapidly, 
and reach their full growth in three months from 
their birth. When uritated, the Slug pours out 
from the whole surface of its body a copious white 
mucus, of the consistence of thick white cream, 
which dries into a white membrane. 
