Herbs, probably annual, with branched leafy angular stems to 20 cm. Leaves broadly ovate in outline, bipinnate with 3 or 4 pairs of stalked pinnae, each with 1 or 2 pairs of shortly stalked distant leaflets that are entire to deeply divided into ovate dentate lobes. Upper leaves and leaves of late branches much smaller than those of middle of stem. Racemes shortly stalked, "leaf-opposed," very dense at first, soon elongating, up to 10-flowered; bracts rhombic-obovate, obtuse to acuminate, with a short indistinct stalk, equaling or longer than pedicels. Pedicel 1-2 mm (to 4 mm in fruit) rather thick, slightly arcuately recurved in fruit. Sepals ovate, 1-2 × ca. 1 mm, dentate. Corolla closed, very small (ca. 5 mm) and ecalcarate, as if stunted in bud stage, completely cleistogamous; outer petals with very narrow dentate crests. Stigma transversely oblong with indistinct lateral papillae and 2 apical papillae. Capsule fusiform, ca. 20 × 4 mm, many seeded, usually crowned at apex by withered corolla, which is broken loose from pedicel by growing fruit. Seeds in 2 rows, ca. 1.75 mm, rounded in outline, rounded on back (i.e., not keeled), sides with small linear impressions, toward back finely tuberculate; elaiosome flat, membranous, partly folded back over seed, easily becoming detached; hilum broad. Fl. and fr. May.
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