Suborder I. Cabómbeæ. Sepals and petals each 3 or sometimes 4, hypogynous and persistent. Stamens definite (3–18). Pistils 2–18, free and distinct, coriaceous and indehiscent, 1–3-seeded on the dorsal suture.—Stems slender, leafy, coated with mucilage. Flowers small.
1. Cabomba. Stamens 3–4. Carpels 2–3. Submersed leaves capillary-multifid.
2. Brasenia. Stamens 12–18. Carpels 4–18. Leaves all peltate.
Suborder II. Nelumbòneæ. Sepals and petals numerous in several rows, passing gradually into each other, and with the indefinitely numerous stamens hypogynous and deciduous. Pistils several, 1-ovuled, separately immersed in the obconical receptacle, which is much enlarged and broadly top-shaped at maturity, the imbedded nut-like fruits resembling small acorns. Embryo large; no albumen.—Petioles and peduncles all from the tuberous rootstock, the centrally peltate leaves and the flowers large.
3. Nelumbo. Character of the Suborder.
Suborder III. Nymphæaceæ proper. Sepals 4–6, and petals numerous in many rows, persistent or decaying away, either hypogynous or variously adnate to the surface of the compound 8–30-celled ovary, which is formed by the union of as many carpels; the numerous ovules inserted over the whole inner face of the cells, except at the ventral suture. Stigmas radiate as in Poppy. Fruit baccate, with a firm rind. Petioles and peduncles from a thick rootstock.
4. Nymphæa. Petals adnate to the ovary, large; the stamens on its summit.
5. Nuphar. Petals (very small and stamen-like) and stamens inserted under the ovary.
Sepals 3. Petals 3, oval, bi-auriculate above the very short claw. Stamens 3–6; anthers short, extrorse. Pistils 2–4, with small terminal stigmas. Seeds 3, pendulous.—Slender, mainly submersed, with opposite or verticillate capillary-dissected leaves, a few floating, alternate and centrally peltate. Flowers single on long axillary peduncles. (Probably an aboriginal name.)