Style, if any, and stigma only one; leaves simple; no scarious bracts around the flowers. [Urticaceæ], [461]

Styles 3; embryo straight; flowers involucrate. [Eriogonum], in [Polygonaceæ], [436]

Style or stigmas 2 or 3; embryo coiled or curved.

Stipules not scarious, leaves palmately cleft or palmately compound. Cannabineæ, in [Urticaceæ], [461]

Stipules scarious (or none); leaves opposite. [Illecebraceæ], [426]

Stipules none; but flowers with scarious bracts. [Amarantaceæ], [427]

Stipules and scarious bracts none. [Chenopodiaceæ], [430]

Shrubs or trees.

Ovules a pair in each cell of the ovary.

Fruit 2-celled, a double samara. Acerineæ, in [Sapindaceæ], [115]