One of the principal divisions of Alcyonaria, including those forms which have a firm and usually branched axis, covered with a porous crust, or c Note: The axis is commonly horny, but it may be solid and stony (composed of calcium carbonate), as in the red coral of commerce, or it may be in alternating horny and stony joints, as in Isis. See Alcyonaria, Anthozoa, C....
