The Collaborative International Dictionary of English v.0.48:

Polystomata \Pol`y*stom"a*ta\, n. pl. [NL., from Gr. poly`s many
   + ?, ?, mouth.] (Zool.)
   A division of trematode worms having more two suckers. Called
   also Polystomea and Polystoma.
   [1913 Webster]