Rugosa

1 definition found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Rugosa \Ru*go"sa\, n. pl. [NL. See {Rugose}.] (Paleon.)
     An extinct tribe of fossil corals, including numerous
     species, many of them of large size. They are characteristic
     of the Paleozoic formations. The radiating septs, when
     present, are usually in multiples of four. See
     {Cyathophylloid}.


     [1913 Webster]