After a shower of rain, many snails come out among the grass and bushes.
They can be seen moving slowly among the wet vegetation. Snails need a great deal of moisture for their active life and that is why they come out after rain, but retire to their shells and bury themselves in the ground during periods of drought.
In winters, they hibernate after sealing the opening of the shell with a plug of sticky material, which keeps them away from the cold. As snails need a good amount of moisture, they also come out early in the morning when there are dew drops on the ground.
Below Snails info from Wikipedia (Read More):-
The word snail is a common name for almost all members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word snail is used in a general sense, it includes sea snails, land snails and freshwater snails.
Snails lacking a shell or having only a very small one are usually called slugs. Snails that have a broadly conical shell that is not coiled or appears not to be coiled are usually known as limpets.
Snails can be found in a wide range of environments from ditches, deserts, and the abyssal depths of the sea. Although most people are familiar with terrestrial snails, land snails are in the minority. Marine snails have much greater diversity and a greater biomass. The great majority of snail species are marine. Numerous kinds can be found in fresh water and even brackish water. Many snails are herbivorous, though a few land species and many marine species are omnivores or predatory carnivores.
http://en.wikipedia.org/wiki/Snails
