Littorina \Lit"to*ri"na\, n. [NL. See Littoral.]

(Zo["o]l.) A genus of small pectinibranch mollusks, having thick spiral shells, abundant between tides on nearly all rocky seacoasts. They feed on seaweeds. The common periwinkle is a well-known example. See Periwinkle.

Source: Webster's Revised Unabridged Dictionary (1913)