1 | Flowers all sessile. Tepals united into a tube. Capsules included in bracts or spathes. |
1' | Flowers all pedicelled. Tepals free or nearly so. Capsules exserted from bracts or spathes. |
2 | Flowers actinomorphic. Inner tepals inconspicuous. Stamens united into an undivided or trifid tube. Caespitose or rhizomatous herbs or undershrubs |
2' | Flowers ± zygomorphic. Tepals unequal. Stamens free. Cormogenous herbs. |
3 | Tepals clawed. Stamens free. |
3' | Tepals not clawed. |
4 | Cormogenous herbs. Stamens appressed against the back of the style-arms. Ovary not beaked. Style trifid with bilobed arms |
4' | Rhizomatous herbs. Stamens not appressed against the back of the style-arms. Ovary beaked. Style trifid with undivided arms |
5 | Tepals shortly connate, subequal. Stamens united into a tube, rarely nearly free. Caespitose to rhizomatous herbs |
5' | Tepals free, the inner ones smaller. Stamens free. Bulbous herbs |