Hydrocorallia

from The Collaborative International Dictionary of English v.0.48
Hydrocorallia \Hy`dro*co*ral"li*a\, n. pl. [NL. See {Hydra}, and
   {Coral}.] (Zool.)
   A division of Hydroidea, including those genera that secrete
   a stony coral, as Millepora and Stylaster. Two forms of
   zooids in life project from small pores in the coral and
   resemble those of other hydroids. See {Millepora}.
   [1913 Webster]
    

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