1101. Aquatic soils are such as are either wholly or partially inundated with water, and are fitted to produce such plants only as are denominated aquatics. Of aquatics there are several subdivisions according to the particular situations they affect, or the degree of immersion they require. One of the principal subdivisions of aquatics is that of marine plants, such as the Fuel and many of the A'lgï¾µ, which are very plentiful in the seas that wash the coasts of Great Britain, and are generally attached to stones and rocks near the shore. Some of them are always immersed ; and others, which are situated above low water mark, are immersed and exposed to the action of the atmosphere alternately. But none of them can be made to vegetate except in the waters of the sea. Another subdivision of aquatics is that of river plants, such as Chara, Potamogeton, and Nymphï¾µ'a which occupy the bed of fresh water rivers, and vegetate in the midst of the running stream; being for the most part wholly immersed, as well as found only in such situations. A third subdivision of aquatics is that of paludal or fen plants, being such as are peculiar to lakes, marshes, and stagnant or nearly stagnant waters, but of which the bottom is often tolerably clear. In such situations you find the Isoctes lacustris, flowering rush, water ranunculus, water violet, and a variety of others which uniformly affect such situations ; some of them being wholly immersed, and others immersed only in part.
