“The medusa glided gracefully through the crystal-clear waters of the ocean.”

“Hydra lives in freshwater, lacks a ciliated planula, and has clearly lost a medusa stage during its ancestry.”

“Cnidarians show an alternation of generations in which two body forms, the polyp and the medusa, alternate.”

“There are three subgroups within the cnidarians that have medusae, cubozoans, hydrozoans, and scyphozoans.”

“Noteably, all epipelagic, midwater, and deepsea medusae have very simple, reduced, or absent ocelli.”

“In polyps, medusae, and worms, all longitudinal and circumferential muscles attach to the thin body wall over a wide area.”