WATER-LILY, a somewhat vague term, given to almost any floating plant with conspicuous flowers, but applying more especially to the species of Xympliwct and Nuphar. These are aquatic plants with their thick fleshy rootstocks or tubers embedded in the mud, and throwing up to the surface circular shield-like leaves, and leafless flower-stalks, each terminated by a single flower, often of great beauty, and consisting of four or five sepals, and numerous petals gradually passing into the very numerous hypogynous or perigynous stamens without any definite line of demarcation between them. The ovary consists of numerous carpels united together and free, or more or less embedded in the top of the flower-stalk. The ovary has many cavities with a large number of ovules attached to its walls, and is surmounted by a flat stigma of many radiating rows as in a poppy. The fruit is baccate, and the seeds are remarkable for having their embryo surrounded by an endosperm as well as by a perisperm. The anatomical construction of these plants presents many peculiarities which have given rise to discussion as to the allocation of the order among the dicotyledons or among the monocotyledons, the general balance of opinion being in favour of the former view. The leaf-stalks and flower-stalks are traversed by longitudinal air-passages, whose disposition varies in different species. The species of Nyimplara are found in every quarter of the globe. Their flowers range from white to rose-coloured, yellow, and blue. Some expand in the evening only, others close soon after noon. Nymph= alba is common in some parts of Britain, as is also the yellow .2V-uplatr luteum. The seeds and the rhizomes contain an abundance of starch, which renders them serviceable in some places for food.
Under the general head of water-lily are included the lotus of Egypt, J.Aryrnigimu Lotus, and the sacred lotus of India and China, .Arclumbiu• speciosum, formerly a native of the Nile, as shown by Egyptian sculptures and other evidence, but no longer found in that river. The gigantic Victoria sepia, a native of tropical South America, also belongs to this group.