Animals having no spine. This group originally contained Spongiaria, Cnidaria and Ctenophora. Coelenterata is a term which generally includes the cnidarians and ctenophores. As the phylum Cnidaria does not include the ctenophores, the two terms are not interchangeable.
The specific term now used by biologists to describe members of a Phylum which are principally marine animals, radially symmetrical, and which have tentacles (i.e. jellyfish). Reproduction usually encompasses a polyp and/or medusa stage. Previously this Phylum was aggregated with others under the term coelenterates.... cnidaria
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