58 Second Report on Economic Zoology . 
the popular idea that the occasional snail-plagues come in the rain- 
clouds. As soon as the sun shines they crawl to some shelter — 
under stones, moss, or beneath the leaves of the plants they attack. 
The eggs are generally round, white,, semi-transparent bodies, and are 
always laid in batches in slanting galleries under ground formed by 
the “ mother ” snail. The slugs ( Limacidse ), unlike the snails, have 
only a rudimentary shell, or an indefinitely formed one placed under 
the mantle. They mostly frequent damp and shady places, and 
during day-time they bury themselves in tunnels under the earth, 
il nlike the snails, they generally deposit their eggs singly under the 
ground, and the eggs are very numerous. The two chief genera are 
Avion and Umax , the former being distinguished by having a slime- 
gland in the posterior extremity, and by having the respiratory orifice 
in front instead of behind the shield. They both feed at night, 
selecting the tenderest and choicest plants, but they will devour 
almost anything. The Limaces are very fond of indoor habitations, 
being found in cellars and outhouses. They destroy the corks in 
wine-cellars, and do much damage in that way ; but, on the other 
hand, it is said they live upon the destructive “ dry-rot ” fungus. 
They all exude a glutinous kind of slime. 
The following species of snails have been brought to my notice 
every now and then as doing much damage to farm crops and 
vegetables : — 
The Garden Snail, Helix aspersa , Muller, is a large and abundant 
species, often doing much harm in the garden, not only to vegetables 
and flowering plants, but even to wall-fruit. Several instances of 
the total destruction of peach and apricot leaves by this snail 
have been brought to my notice. The years 1884 and 1889 were 
remarkable for the number of this snail seen about. The eggs are 
laid in small batches in the earth, about sixty or seventy in each 
heap. The ova are white, shining, globular bodies. They hatch in 
about fifteen days if kept in damp places. The young snails are 
almost colourless, and the shell is thin and transparent ; they grow 
rapidly. Drought and cold are erroneously considered prejudicial to 
all snails. At the approach of winter they collect together and 
exude a slimy matter, which hardens on exposure and closes the 
aperture of the shell. They may then be found hibernating together 
in crevices in walls, in old trees, and under rubbish, united together 
by the agglutinated slime. I have notes of the damage caused by 
this snail in most counties of the south of England. 
The Wood Snail {II. nemoralis , Linn.) is an extremely abundant 
snail in hedgerows and upland pastures, and especially in clover, 
