Annual glabrous branching erect or diffuse herbs, with small yellow flowers and 3-foliolate leaves. Calyx of 4 sepals. Petals 4, sessile, not clawed. Receptacle short, glandless. Stamens 6, inserted on the receptacle. Ovary short, long-stalked. Capsule short, rhomboid or trapezoid, often broader than long, 4-10-seeded. [Diminutive of Cleome.]

A genus of about 8 species, natives of southwestern North America, extending into Mexico. Type species: Cleomella mexicana DC.

1. Cleomella Angustifòlia Torr. Northern Cleomella

Fig. 2117

Cleomella angustifolia Torr.; A. Gray, Pl. Wright. 1: 12. 1852.

Generally erect, 1°-1 1/2° high, branching above. Leaflets linear-lanceolate or linear-oblong, longer than the petiole; bracts linear, simple; flowers yellow, 2"-3" broad; pedicels very slender, 1/2' long in fruit; pod flattened, rhomboid, 2"-3" broad, about 2" high, pointed, raised on a very slender stipe 2"-4" long, its valves almost conic; placentae persistent after the valves fall away, each bearing about 3 seeds.

Plains, Nebraska and Colorado to Texas and New Mexico. Summer.