What is the class of the Coelenterata which includes the corals and sea anemones. The three principal groups or orders are Acyonaria, Actinaria, and Madreporaria called?

anthozoa — The class of the Coelenterata which includes the corals and sea anemones. The three principal groups or orders are Acyonaria, Actinaria, and Madreporaria. (Webster's 1913.)

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