calamite

from The Collaborative International Dictionary of English v.0.48
Calamite \Cal"a*mite\, n. [L. calamus a reed: cf. F. calamite.]
   (Paleon.)
   A fossil plant of the coal formation, having the general form
   of plants of the modern {Equiseta} (the Horsetail or Scouring
   Rush family) but sometimes attaining the height of trees, and
   having the stem more or less woody within. See {Acrogen}, and
   {Asterophyllite}.
   [1913 Webster]
    

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