Scolopendrium vulgare

from The Collaborative International Dictionary of English v.0.48

Hart's-tongue \Hart's"-tongue`\ (h[aum]rts"t[u^]ng`), n. (Bot.)
      (a) A common British fern ({Scolopendrium vulgare}), rare
          in America.
      (b) A West Indian fern, the {Polypodium Phyllitidis} of
          Linn[ae]us. It is also found in Florida.
          [1913 Webster]