This non-flowering, but cryptogamic plant floats on the water. It has no roots, but takes water and nutritiens by its leaves out of the water. The floating, pale green, rounded leaves are inter-connected by thin, densely haired stalks. The spores (may appear in September-October) grow in rounded, haired, spore-boxes. A not winter-hardy plant for sunny and warm positioned ponds with moderately nutritious water. The plants provide for shade in the water below. Along the margins of the plants constantly new branches with (still) small leaves are formed. Can be hibernated frost-free. Endemic in Europe, Korea and Japan.