This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
To this genus belongs our White Water-Lily, together with several splendid, though unfortunately not hardy species, having crimson, rose, or blue flowers, natives of Australia and South Africa. Besides the flowers being much larger and never yellow, this is technically distinguished from Nuphar by having 4 sepals and numerous conspicuous petals as large as or larger than the sepals. Dedicated by the Greeks to the water-nymphs. They are all Summer-flowering plants.
Fig. 26. Nympkaea alba. (1/6 nat. size.)
2. N. odorata. - A North American species, closely resembling the last, but the flowers are slightly tinged with rose and deliciously scented.
N. nitida, a native of Siberia, has elliptical cordate shining deeply-lobed leaves with spreading lobes and white flowers, and N. pygmaea is a charming miniature of the foregoing. A native of China, and equally hardy.