Stock stout up to 1·8 cm. diam. with deeply descending taproot, crowned by dense rosette of basal lvs. Radical lvs up to c. 7 cm. long, obovate-spathulate to linear-spathulate, narrowed into flat petiole, apex acute to obtuse, coarsely irregularly inciso-serrate, coriac., glab. to sparsely clad in simple long hairs. Cauline lvs smaller, narrower, upper- most subentire. Infl. of few to many simple or branched stems, forming rounded or elongate masses up to 3 dm. or more tall; fls ∞ in the racemes, pedicels slender, ascending. Sepals c. 4 mm. long, narrow- oblong; petals white, ± 6-8 mm. long, narrow-spathulate, long-clawed. Siliques 4 cm. or more long, arcuate to straight, c. 1·5-2 mm. wide; style slender, c. 1 mm. long. Seeds 1-1·5 mm. long, compressed, reddish brown.