(Actinozoa, or ray-like animals.) A soft, pulpy polyp with a flower-like or ray-like fringe of tentacles, in the middle of which is the mouth, leading into a hollow sac or stomach. It is of the shape of a column, with a sucking surface in the base that enables it to move much like a snail, but more slowly. From the tentacles are thrown small darts, by which it seizes any crab or worm or small fish for food.