With 2 or more parietal very many-seeded placentæ; stamens 4. [Orobanchaceæ], [393]
Ovary and fruit more or less 4–5-celled. [Pedaliaceæ], [399]
Ovary and pod 2-celled, but the 2 placentæ parietal. [Bignoniaceæ], [398]
Ovary and pod 2-celled; placentæ in the axis.
Seeds rarely few, not on hooks, with albumen. [Scrophulariaceæ], [377]
Seeds few, borne on hook-like or other projections of the placentæ; no albumen. [Acanthaceæ], [399]
[*][*] Corolla somewhat irregular; stamens (with anthers) 5.
Stamens free from the corolla; anthers with their cells opening by a hole or chink at the top. [Rhododendron], in [Ericaceæ], [320]
Stamens inserted on the corolla.
Ovary deeply 4-lobed around the style. [Echium], in [Borraginaceæ], [367]