Snail. Snails are small, slow-crawling animals with a soft body protected by a coiled shell. They move with wave-like motions of their single foot, secreting a slime as they go to make their travel easier. The psalmist may have had this peculiar motion in mind when he spoke of the snail “which melts away as it goes” (Ps. 58:8).

The snail in (Leviticus 11:30) (KJV ) is probably a skink, a type of sand lizard.

Source: [Anon-Animals]