Wallpaper Jelly Dancing Underwater 1920X1200 Desktop Wallpaper Description: Jelly Dancing Underwater 1920X1200 Jelly Dancing Underwater 1920X1200          Medusa Jellyfish are the major non- polyp form of individuals of the phylum Cnidaria . They are typified as free-swimming marine animals consisting of a gelatinous umbrella -shaped bell and trailing tentacles.