SLUGS. 515 
number of species. Most of the Snails have a shell large enough to permit 
the animal to withdraw itself wholly into the protecting domicile. 
The genus Helix, which is universally accepted as the type of this family, 
is of enormous extent, both in numbers and in range of locality, containing 
more than tourteen hundred species, and spread nearly over the whole 
earth, 
Our present example is the common SNAIL, which is even now largely con- 
sumed in many parts of the world, and is regularly fed and fattened for that 
urpose. 
ee thought a delicacy by those who are sufficiently strong-minded to eat 
it; and it is quite common to see, even in Paris, the poorer orders dressing 
their dinner of Snails on an iron plate, heated over burning charcoal. 
An allied species, the Edible Snail, (4/ed¢% pomatia) was introduced into 
England by tue Romans, and still exists in many places. 
Towards the end of autumn, the Snail ceases to feed, withdraws itself to 
some sheltered spot, mostly under grass, moss, or dried leaves, and then 
.sets about making its winter habitation. This process is very curious, and 
is thus described by Mr Bell :— 
“ A large quantity of very viscid mucus is secreted on the under surface of the 
foot, to which a layer of earth or dead leaves adheres ; this is turned on one 
side, and, a fresh secretion being 
thrown out, the layer of earth mixed 
with mucus 1s left. ‘he animal then 
takes another layer of earth on the 
bottom of the foot, turns it also to the 
part where he intends to form the 
wall of his habitation and leaves it 3&8 
in the same manner, repeating the “- 
process until the cavity is sufficiently \< 
large, and thus making the sides 
smooth, even, and compact. In form- 
ing the dome or arch of the chamber, 
a similar method is used; the foot 
collecting on its under surface a quantity of earth, and the animal, turning 
it upwards, leaves it by throwing out fresh mucus ; and this is repeated until 
a perfect roof is formed. 
“As I have very often watched this curious process, I am certain of the 
facts. On removing very carefully the portion of the roof soon after 
its completion, I was enabled to see the formation of the operculum. 
In about an hour, or even less, the whole surface of the collar of the 
mantle instantaneously pours out the calcareous secretion in considerable 
quantity. 
“This is at first a fluid or thick cream, but very soon acquires exactly the 
consistence of birdlime, being excessively adhesive and tenacious ; and in 
about an hour after it is poured out it is perfectly solid.” 
WE. now arrive at the great family of Limacide, or SLUGS, a race of 
beings which many a gardener doubtless wishes extinct. 
In these creatures the foot and body are indistinguishable from each other ; 
the head is retractile ; and the whole creature can be gathered into a short 
rounded mass, looking so like a pebble that it would escape a casual glance. 
At the first view, the Slugs appear to be destitute of shell, but on a closer 
examination the shell is found upon the fore part of the body, and either 
entirely or partly buried beneath the integuments. d 
The GREAT GREY SLUG is the largest of the British species, and when 
furnished with abundant food on which it can fatten itself during the night, 
LL2 
COMMON SNAIL.—(Helix aspersa.) 
