Source : Webster's Revised Unabridged Dictionary (1913)

Protophyte \Pro"to*phyte\, n. [Proto- + Gr. ? a plant.] (Bot.)
   Any unicellular plant, or plant forming only a plasmodium,
   having reproduction only by fission, gemmation, or cell
   division.

   Note: The protophytes ({Protophyta}) are by some botanists
         considered an independent branch or class of the
         vegetable kingdom, and made to include the lowest forms
         of both fungi and alg[ae], as slime molds, Bacteria,
         the nostocs, etc. Cf. {Carpophyte}, and {O["o]phyte}.