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individuals of the medusoid (sexually reproducing) generation of coelenterates of the class Scyphozoa. The umbrella, which may be flat or bell-shaped, is semitransparent and often brightly colored or with colored markings. The margins of the mouth are drawn out into four mouth arms, which are sometimes branched. There are often four, eight, or 16 simple or branching radial canals of the digestive system and a ringshaped canal. The margin of the umbrella has eyespots, statocysts, and, in many cases, marginal tentacles. The umbrella varies in diameter from several centimeters to 2 meters (in Cyanea). All Scyphomedusae except those of the order Stauromedusae live deep in the ocean and are capable of swimming. [25–376–1 ]