Source : Webster's Revised Unabridged Dictionary (1913)

Rhodosperm \Rho"do*sperm\, n. [Gr. "ro`don the rose + spe`rma a
   seed.] (Bot.)
   Any seaweed with red spores.

   Note: As the name of a subclass, Rhodosperms, or
         {Rhodosperme[ae]}, is synonymous with {Floride[ae]}
         (which see.)

Phycoerythrin \Phy`co*e*ryth"rin\, Phycoerythrine
\Phy`co*e*ryth"rine\, n. [Gr. ? seaweed + E. erythrin, -ine.]
   A red coloring matter found in alg[ae] of the subclass
   {Floride[ae]}.

Florideae \Flo*rid"e*[ae]\, n. pl. [NL., from L. flos, floris, a
   flower.] (Bot.)
   A subclass of alg[ae] including all the red or purplish
   seaweeds; the Rhodosperme[ae] of many authors; -- so called
   from the rosy or florid color of most of the species.