[*][*] Root perennial; leaves pinnate; flowers showy.
4. C. praténsis, L. (Cuckoo Flower.) Stem ascending from a short rootstock, simple; leaflets 7–13, those of the lower leaves rounded and stalked, of the upper oblong or linear, entire, or slightly angled-toothed; petals (white or rose-color) thrice the length of the calyx; pod 9–15´´ long, 1´´ broad; style short.—Wet places and bogs, Vt. to N. J., Wisc., and northward; rare. May. (Eu.)
[*][*][*] Root mostly biennial or annual; leaves pinnate; flowers small, white.
5. C. hirsùta, L. (Small Bitter Cress.) Glabrous or beset with scattered hairs; stems (3´–2° high) erect or ascending from the spreading cluster of root-leaves; their leaflets rounded, those of the upper leaves oblong or linear and often confluent, all either toothed, angled, or entire; pods linear, very narrow, erect or ascending; style variable.—Wet places; common. May–July. The ordinary form corresponds closely to the European var. sylvática, Gaud. The typical imperfectly developed annual form, with only 4 stamens and rather strict pods, occurs very rarely. A form answering to C. parviflora of Europe, with mostly linear leaflets and pods often erect on spreading pedicels, is occasionally found in drier localities. (Eu., Asia.)
5. ÁRABIS, L. Rock Cress.
Pod linear, flattened; placentas not thickened; the valves plane or convex, more or less 1-nerved in the middle, or longitudinally veiny. Seeds usually margined or winged. Cotyledons accumbent or a little oblique.—Leaves seldom divided. Flowers white or purple. (Name from the country, Arabia. See Linn. Phil. Bot. § 235.)
§ 1. ARABIS proper. Seeds in one row in each cell, orbicular or nearly so, more or less wing-margined; cotyledons strictly accumbent.
[*] Low, chiefly biennials, diffuse or spreading from the base.
1. A. Ludoviciàna, Meyer. Nearly glabrous, often annual; leaves all pinnately parted into oblong or linear few-toothed or entire divisions, those of the lower leaves numerous; pedicels very short; flowers small, white; pods rather broadly linear, spreading, flat; seeds winged.—Open grounds, Va. to Mo., and southward.
[*][*] Erect and simple leafy-stemmed biennials, with simple leaves, white or whitish flowers, narrow but flattened ascending or erect pods, and nearly wingless seeds.