; class Anthozoa, subclass Octocorallia)
An order of colonial octocorals that have an elongate primary polyp embedded in mud on the sea-bottom. The distal end of the primary polyp bears secondary polyps, usually on lateral branches. The polyps are supported by a calcareous or horny skeleton. They are first known as fossils from Cretaceous and Tertiary strata, and with uncertainty from the Silurian. The order contains two suborders, 14 families, and about 40 genera.
Subjects: Zoology and Animal Sciences.