Source : Webster's Revised Unabridged Dictionary (1913)

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 : WordNet®

Littorina
     n : type genus of the family Littorinidae: periwinkles [syn: {genus
         Littorina}]