We tend to associated mollusks with the sea, yet they walk among us. Well, slide anyway.
Slugs have vestigial shells and have to use their slime to move, hold in water, and for protection. Best not to lick them.
They are key part of their ecosystem. They recycle plant matter and disperse seeds and spores.
Mastodonians in the PNW Olympic Peninsula area live near the second largest slug in the world: the Banana Slug, which can reach 10 inches long.