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These plants are very remarkable. They lived, no doubt, at one time on the land, like most of the flowering plants. But, like the whale and the seal, they have been driven to take refuge below the ocean. They are not easily seen, and, indeed, one may wander for years along the sea-coast and never suspect that great meadows of Zostera (the Eelwrack, Grasswrack, or Sea-grass) are flourishing under water.