396 
THE OCEAN WORLD. 
organs of touch. Other functions are sometimes attributed to then 1 > 
the anterior tentacles are sometimes considered to be the organs oi 
smell. This, at all events, is certain, that the sun.il is very sensible 
of strong odours, and is easily attracted by many plants the odour of 
which pleases them. 
The black point which terminates the first pair of tentacles ha * 8 
been considered as eyes ; but the existence of a visual organ is nof 
quite admissible in the snail. They are quite insensible to sudden 
changes of light ; they always travel in the dark, and never recogn lS0 
obstacles placed before them. We may add that the snail is destitm 1 
of all organs o t hearing. No noise appears to affect it, at least till 
the noise is so near as to agitate the air which immediately surround 3 
it. Indeed, the snail has not been well treated by Nature ; the poor 
creature is at once blind, deaf, and dumb. 
The snails are male and female in the same individual, each being 
at once male and female, or hermaphrodite. Their eggs are roundish' 
heavy, and of a whitish colour. The animal deposits them on if 1 
soil in little irregular heaps ; at other times it deposits them one after 
the other, like the grains of a chaplet, in holes which it digs in 
soil, or in the natural excavations created by moisture. The egg 3 
are even found in the hollows of old trees ; in fissures of Avails 1,1 
rocks. 
TV hen the young Helix issues from the egg, they are already P l8 
vided with an extremely thin membranous shell. The timid a»d 
tender youth is conscious of its weakness and full of humility- ^ 
rarely trusts itself out of the obscure hole in which it was hatched 
when it does, it is only at night, dreading the desiccating air, 
above all, the sun’s rays, even with the house it always carries ^ 
it for shelter. 
This calcareous and velluted house is spiral, which the animal 
the inappreciable advantage of transporting without fatigue — a 
wanderer. It is light, and sometimes quite disproportionate to fb® 
body of the animal, which it. covers only in that part which contain 3 
the viscera and respiratory organs. The form of the shell is generally 
much variegated. Some are flattened, others are orbicular or globose ; 
in some the spiral is very pointed. The edges of the shell are some- 
times simple, sharp, and pointed ; others, on the contrary, thick and 
inverted, presenting an edging of great solidity. 
