WATER-LILY, a name somewhat vaguely given to almost any floating plant with conspicuous flowers, but applying more especially to the species of Nymphaea, Nuphar, and other members of the order Nymphaeaceae. These are aquatic plants with 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 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 berry-like, 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 flowerstalks are traversed by longitudinal air-passages, whose disposition varies in different species. The species of Nymphaea 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. Nymphaea alba (Castalia alba) is common in some parts of Britain, as is also the yellow Nuphar luteum (Nymphaea lutca). The seeds and the rhizomes contain an abundance of starch, which renders them serviceable in some places for food.
Of recent years great strides have been made in the culture of new varieties of water-lilies in the open air. Many beautiful Nymphaea hybrids have been raised between the tender and hardy varieties of different colours, and there are now in commerce lovely forms having not only white, but also yellow, rose, pink and carmine flowers. In many gardens open-air tanks have been fitted up with hot-water pipes running through them to keep the water sufficiently warm in severe weather. The open-air water-lily tank in the Royal gardens, Kew, is one of the latest and most up-to-date in construction. These coloured hybrids were originated by M. Latour Marliac, of Temple-sur-Lot, France, some of the most favoured varieties being cornea, chromatella, flammea, ignea, rosea, Robinsoni, Aurora, blanda, etc.
Amongst hardy species of Nymphaea now much grown are Candida, nitida, odorata, pygmaea and tuberosa, all with white, more or less sweet-scented flowers ; flava, yellow, and sphaerocarpa, rpse<armine. Amongst the tender or hothouse Nymphaeas the following are most noted: blanda, white; devoniensis, scarlet (a hybrid between N. Lotus and N. rubra) ; edulis, white ; elegans, yellowish white and purple; gigantea, blue; kewensis, rose-carmine (a hybrid between N. devoniensis and N. Lotus); Lotus, red, white; pubescens, white; scutifolia, bright blue; stellata, bli'e, with several varieties; and Sturtevanti, a pale-rose hybrid.
Under the general head of water-lily are included the lotus of Egypt. Nymphaea' Lotus, and the sacred lotus of India and China, Nelumbium speciosum, formerly a native of the Nile, as shown by Egyptian sculptures and other evidence, but no longer found ia that river. The gigantic Victoria regia, with leaves 6 to 7 ft. in diameter and flowers 8 to 16 in. across, also belongs to this group. It grows in the backwaters of the Amazon, often covering the surface for miles ; the seeds are eaten under the name water maize.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)