The Collaborative International Dictionary of English v.0.48:

Fungia \Fun"gi*a\, n. [NL., fr. L. fungus mushroom: cf. F.
   fongie.] (Zool.)
   A genus of simple, stony corals; -- so called because they
   are usually flat and circular, with radiating plates, like
   the gills of a mushroom. Some of them are eighteen inches in
   diameter.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Fungia
    n 1: a genus comprising the usual mushroom corals [syn:
         Fungia, genus Fungia]