Psoralea
(from psoraleos, warted or scurfy; in reference to the plants being, for the most part, sprinkled all over or roughened with glandular dots or wart-like points). Scurfy Pea. ORD. Leguminosae. A large genus (about 100 species have been described) of greenhouse or hardy, annual, biennial, or perennial herbs, shrubs, or sub-shrubs, inhabiting South Africa, North and South America, Australia, and the tropical and temperate regions of Asia, Europe, and North Africa. Flowers purple, blue, pink, or white, capitate, spicate, subracemose, or fasciculate, rarely solitary; calyx lobes sub-equal or at length larger, the two upper ones often connate; petals nearly as long, or shorter than the keel; standard ovate or orbiculate. Leaves usually compound, consisting of three to five leaflets, though occasionally the leaves are simple; stipules adhering to the stalk. The Cape species thrive in well-drained, sandy peat, and the others in ordinary garden soil. The shrubby kinds are increased, in April or May, by cuttings of the half-ripened shoots, inserted in sand, under a glass. The herbaceous species are propagated by divisions when the new growth commences. The following is a selection of the best kinds introduced. Except where otherwise stated, they are greenhouse, Cape shrubs.
P. aculeata (prickly).* fl. blue and white mixed, axillary, solitary, sessile, approximate. June and July. l. trifoliolate; leaflets cuneiform, ending in a recurved mucrone, glabrous; stipules prickle-formed. h. 2ft. to 3ft. 1774. (B. M. 2158.) P. aphylla (leafless). fl. blue; keel and wings white; pedicels axillary, short, solitary, one-flowered. May to August. l., lower ones simple or trifoliolate; leaflets linear-lanceolate, upper ones abortive, scale-formed. h. 4ft. to 7ft. 1790. (B. M. 1727.) P. arborea (tree-like). fl. bluish; pedicels axillary, one-flowered, longer than the leaves. May. l. impari-pinnate; leaflets linear-lanceolate; stipules recurved. h. 6ft. to 8ft. 1814. (B. M. 2090.) P. glandulosa (glandular). fl. white, marked with blue, disposed in axillary, spicate racemes; bracts very small, ciliated. May to September. l. ternate; leaflets ovate-lanceolate, acuminate; petioles scabrous. Stem erect. h. 4ft. Chili, &c., 1770. Half-hardy shrub. (B. M. 990.) P. melilotoides (Melilot-like). fl. pale purple; peduncles racemose; racemes or spikes linear. August. l. pinnately trifoliolate; leaflets lanceolate, glandular beneath. h. 1ft. to 2ft. North America, 1814. Hardy perennial herb. (B. M. 2063; B. R. 454.) P. Mutisii (Mutis'). A synonym of Dalea Mutisii.
P. pinnata (pinnate-leaved).* fl. blue, striped; pedicels axillary, one-flowered, much shorter than the leaves. May to July. l. impari-pinnate; leaflets two or three pairs, linear, and, as well as the branchlets, slightly puberulous. h. 3ft. to 6ft. 1690. (A. B. R. 474.)