Corals are marine organisms from the class Anthozoa and exist as small sea anemone–like polyps, typically in colonies of many identical individuals. The group includes the important reef builders that are found in tropical oceans, which secrete calcium carbonate to form a hard skeleton.
GalleriesCorals and Sea Anemone
Benson John Lossing, ed. The New Popular Educator (London, England: Cassell & Company Limited, 1891)