7. CÝTISUS, Tourn. Broom.
Calyx campanulate, with 2 short broad lips. Petals broad, the keel obtuse and slightly incurved. Stamens monadelphous. Pod flat, much longer than the calyx. Seeds several, with a strophiole at the hilum.—Shrubs, with stiff green branches, leaves mostly digitately 3-foliolate, and large bright yellow flowers. (The ancient Roman name of a plant, probably a Medicago.)
C. scopàrius, Link. (Scotch Broom.) Glabrous or nearly so (3–5° high); leaflets small, obovate, often reduced to a single one; flowers solitary or in pairs, on slender pedicels, in the axils of the old leaves, forming leafy racemes along the upper branches; style very long and spirally incurved.—Va. and southward. (Nat. from Eu.)
Calyx very deeply 2-lipped. Sides of the standard reflexed; keel scythe-shaped, pointed. Sheath of the monadelphous stamens entire; anthers alternately oblong and roundish. Pod oblong, flattened, often knotty by constrictions between the seeds. Cotyledons thick and fleshy.—Herbs, with palmately 1–15-foliolate leaves, stipules adnate to base of the petiole, and showy flowers in terminal racemes or spikes. (Name from Lupus, a wolf, because these plants were thought to devour the fertility of the soil.)
1. L. perénnis, L. (Wild Lupine.) Perennial, somewhat hairy; stem erect (1–2°); leaflets 7–11, oblanceolate; flowers in a long raceme, showy, purplish-blue (rarely pale); pods broad, very hairy, 5–6-seeded.—Sandy soil, N. Eng. to Minn., Mo., and south to the Gulf.—Var. occidentàlis, Watson, has stems and petioles more villous.—Mich. and Wisc.
2. L. pusíllus, Pursh. Annual, low, villous; leaflets usually 5; racemes short, sessile; flowers purple or rose-color; pods oval, hirsute, 2-seeded.—Central Dak. and Kan., and westward.
9. TRIFÒLIUM, Tourn. Clover. Trefoil.
Calyx persistent, 5-cleft, the teeth bristle-form. Corolla mostly withering or persistent; the claws of all the petals, or of all except the oblong or ovate standard, more or less united below with the stamen-tube; keel short and obtuse. Tenth stamen more or less separate. Pods small and membranous, often included in the calyx, 1–6-seeded, indehiscent, or opening by one of the sutures.—Tufted or diffuse herbs. Leaves mostly palmately, sometimes pinnately 3-foliolate; leaflets usually toothed. Stipules united with the petiole. Flowers in heads or spikes. (Name from tres, three, and folium, a leaf.)
[*] Flowers sessile in dense heads; corolla purple or purplish, withering away after flowering, tubular below, the petals more or less coherent with each other.