Paludina

from The Collaborative International Dictionary of English v.0.48
Paludina \Pal`u*di"na\, n.; pl. L. {Paludin[ae]}, E.
   {Paludinas}. [NL., fr. L. palus, -udis, a marsh, pool.]
   (Zool.)
   Any one of numerous species of freshwater pectinibranchiate
   mollusks, belonging to {Paludina}, {Melantho}, and allied
   genera. They have an operculated shell which is usually
   green, often with brown bands. See Illust. of {Pond snail},
   under {Pond}.
   [1913 Webster]
    

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