Antipatharia

Antipatharia, the "black corals," is an order of the Zoantharia (q.v.). They are colonial animals, and form great plant-like growths; these consist of a central horny axis, attached by its base during life to the rocks or sea bottom on which it lives. This axis is covered by a fleshy layer (known as the coenosarc), and in this the polypes (the separate individuals of the colony) are embedded.