Annual 01 perennial leafy-stemmed or acaulescent herbs, or rarely shrubs, often with rootstocks or scaly bulbs, the sap sour. Leaves mostly palmately 3-foliolate, in some exotic species pinnate or entire and peltate; stipules commonly present as scarious expansions of the petiole-bases; leaflets mostly obcordate. Flowers perfect, in umbel-like or forking cymes, or sometimes solitary; peduncles mostly long. Sepals 5, often unequal. Petals 5, white, pink, purple or yellow. Stamens 10-15 Ovary 5-celled, 5-lobed; styles united or distinct; ovules 2-many in each cavity; fruit a loculicidal globose or columnar capsule, rarely baccate. Embryo straight, in fleshy endosperm.

About 15 genera and about 300 species, chiefly of tropical distribution.

Plants acaulescent, with bulb-like or scaly rootstocks; corolla white, pink or rose-purple.

Sepals without apical tubercles; rootstocks elongated.

1.

Oxalis.

Sepals with apical tubercles; rootstocks bulb-like.

2.

Ionoxalis.

Plants caulescent; corolla yellow.

3.

Xanthoxalis.