One of the reasons that they move so slowly is that they must manufacture a slime track on which they move. For every inch they move, they make a thin layer of slime an inch long. This takes time as well as lots of water and energy. The advantage is that they can move along on almost ANY surface. read more
Plants don't run away, so no need to be able to chase them. Escaping predators is a good reason to develop faster locomotion, but presumably slugs compensate in other ways. read more
Slugs are limited in the same way and use the same method to move. Snails feed on vegetation such as leafy greens, grass and other common plants. They are known for attacking gardens, breeding in damp places and making general nuisances of themselves on human property. Their slow speed makes them easy to gather and reposition. read more
A sea slug, also called marine slug, is the same animal as a snail.The slug does not have a shell. The sea slug moves at a very slowrate. read more