Characters.—Ovules inclosed in an ovary, and fertilized by the application of the pollen to the stigma.
In accordance with the classification followed by De Candolle, the natural orders of this subclass will be arranged in the four following subdivisions: 1st, Monochlamydeae; 2dly, Corolliflorae; 3dly, Calyciflorae, and 4thly, Thalamiflorae.
Subdivision I. Monochlamydeae, De Cand.
Flowers frequently unisexual. Perianth absent, rudimentary or simple, calycine or coloured, free or connate with the ovary.