CnidariaHydrozoaSea AnemonesHydraScyphozoaCubozoaAnemoneAnthozoaNematocystCtenophoraPhylogenyPlacozoaEvolution, MolecularInvertebratesCnidarian VenomsPoriferaRNA, Ribosomal, 28SRNA, Ribosomal, 18SDNA, RibosomalBody PatterningMolecular Sequence DataMetamorphosis, BiologicalGenes, HomeoboxDNA, MitochondrialEncyclopedias as TopicPolypsLife Cycle Stages