Annual, succulent herb, up to 1 m. Stems erect, procumbent or trailing, thick, terete or slightly angular. Leaves 1.5-10 x 1-7.5 cm., ovate-rhombic to deltoid, obtuse or acuminate, cuneate and more or less decurrent into the petiol at base; petiole thick, 0.5-2.5 cm. long. Flowers solitary or 2-3 together, axillary, subsessile. Calyx 3-5, usually 4 unequally-lobed, green outside, yellow-green inside, lobes 2-3 mm. long. Stamens 4-22. Capsule 5-10 mm., smooth, turbinate, subtruncate, crowned with 2-5 horned, 4-10 seeded. Fl. April-May.