Source : Webster's Revised Unabridged Dictionary (1913)

Catallacta \Cat`al*lac"ta\, n. pl. [NL., fr. Gr. ?. See
   {Catallactics}.] (Zo["o]l.)
   A division of Protozoa, of which {Magosph[ae]ra} is the type.
   They exist both in a myxopod state, with branched
   pseudopodia, and in the form of ciliated bodies united in
   free, spherical colonies.