Slugs and snails are gastropods. This is a group of molluscs that have soft bodies and move about on one large foot. Slugs and snails have two pairs of feelers, called tentacles. One pair is used for seeing, the other pair for touch and smell. Most kinds feed on leaves and fungi. Unlike slugs, snails have hard shells. Snails will pull their head and bodies into their coiled shell if they are threatened. Land snails and slugs are hermaphrodites: each has both male and female sex organs. But they still need to mate with each other.

Digestion

The mouth is located beneath the tentacles. Most kinds of slug and snail have thousands of minute "teeth" on their ribbon-like tongue, which is called a radula. The radula’s rough surface helps the animals to tear their food into small, digestible pieces.

Apart from the fact that slugs have no shell, there is little difference between slugs and snails. The two animals live different lifestyles, however. Without a shell, a slug can squeeze itself into much smaller spaces. Its soft, slimy body can easily dry up, however, so it needs to find these spaces when the weather is wet. A snail can retreat into its shell to keep moist.