Annual (?) 15-25 cm. tall, rather slender, branched from base and again ± divided; branches slender, subquadrangular, margined. Basal lvs few, subrosulate, thin; lamina 1-3 cm. × ± 6 mm., spathulate, obtuse or subacute, narrowed to flat petiole 1-2 cm. long. Cauline lvs sessile or lower ones subsessile, broad-ovate to ovate-triangular, subacute, semiamplexicaul, 8-12 mm. long, in distant pairs, sts minutely apiculate. Fls rather plentiful, solitary, terminal on branchlets, occ. paired or in threes. Calyx c. 8 mm. long, cut 3/4 way into ovate-oblong to narrow-ovate subacute lobes. Corolla white, 10-15 mm. long; lobes subacute, veins distinct.