Cyathophylum

Cyathophylum, one of the best known genera of the corals of the extinct group, the "Rugosa" (q.v.). It was common in the seas of the Silurian period, and survived till the Carboniferous. The corals of this genus are generally single, and of a curved and inverted conical form. Some species, however, were compound. The genus is the type of the family Cyathophyllidae, which is of interest, as some recent corals may have to be included in it.