Piqueria
(named after A. Piqueria, a Spanish botanist, who published a translation of Hippocrates in 1757). Including Phalacraea. ORD. Compositae. A genus comprising about half-a-score species of greenhouse or hardy shrubs, or rarely erect annual or perennial herbs, natives of mostly Western South America, from Bolivia to Mexico. Flower-heads white or bluish, small, homogamous, often densely cymose, the cymes corymbose or loosely paniculate; involucre campanulate; receptacle flat or convex, naked. Leaves opposite, toothed or entire. The only species known to cultivation are the two described below. Both are hardy, and of easy culture in ordinary garden soil. P. latifolia may be increased by seeds, and P. trinervia by division. P. latifolia (broad-leaved). fl.-heads purplish, pedicellate; peduncles almost naked, corymbose at apex. July. l. petiolate broadly ovate, truncate at base. h. 1 1/2ft. Peru, 1800. Annual. (R. G. 107.) SYNS. Ageratum latifolium, Phalacraea coelestina.
P. trinervia (three-nerved). fl.-heads white, disposed in loose, corymbose, many-headed panicles. July. l. ovate or oblong-lanceolate, sub-serrate, trinerved. h. 2ft. Mexico, 1798. Glabrous perennial herb. (B. M. 2650.)