Erect, annual herb. Cauline leaves 4.5-5.5 x 3-4 mm, ovate, 3-5 lobed, with truncate base; lobes acuminate, longer than broad, upper antrorse, lower patent (c. 4.5 x 3 mm, 3-lobed in aestival and 5-5.5 x 3.5-4 mm, 4-5 lobed in autumnal form). Racemes lax. Floral leaves 4-5.5 x 3-5 mm, ovate-broadly ovate, 4-6 lobed, with truncate base; lobes acuminate-aristulate, as long as broad or longer than broad, upper antrorse, lower patent (4-4.5 x 3-3.5 mm, ovate, 4-lobed, lobes acuminate in aestival and 5-5.5 x 4-5 mm, broadly ovate, 5-6 lobed, lobes aristulate in autumnal form). Flowers 5.5-7.5 mm long; sessile. Calyx 4-7 mm long; lobes 1-3 x 0.5-1 mm, equal or unequal; tube 2-4 mm long. Corolla white, with dark violet lines, throat yellow, dorsally 5-7 mm long; tube 3-4 mm long, extrnally pubescent especially on the upper lip. Upper lip 3-4 mm long. Lower lip 3-5 mm long; lobes oblong, obcordate, erose-slightly notched, left lobe largest 2.5-4 x 1.5-3 mm, left and right lobes unequal, right lobe 1-4 x 1.5-2 mm, middle lobe 2-4 x 1-2.5 mm. Two anthers with unequal awns and two with equal-subequal awns, densely hairy; hairs short, equalling the longer awn. Capsule 4-5.5 x 1.5-2 mm, (c. 4 x 1.5 mm, in aestival and 5-5.5 x 2 mm in autumnal form), oblong, retuse, equal-subequal to the calyces, ciliate at the upper part; cilia soft. Seeds 4-15 per capsule (4-9 seeds in aestival and 10-15 seeds in autumnal form), oblong, obtuse.