Pisonia
(named in honour of Willem Piso, of Amsterdam, an eminent physician and writer on natural history, who died in 1648). SYNS. Calpidia, Ceodes, Columella, Pallavia, and Torrubia. ORD. Nyctagineae. A genus consisting of about sixty species of unarmed or rarely spiny, glabrous or pubescent, erect or rarely sub-scandent, stove or greenhouse trees and shrubs, mostly natives of tropical America; a few are found in Asia and the Pacific Islands, and six in the Mascarene Islands. Flowers pink, greenish, or yellow, small, disposed in paniculate, sub-sessile, or pedunculate cymes, two or three-bracteolate; male perianth tubular-or infundibular-campanulate, female large and oblong; limb of five short teeth or lobes. Fruit a small or rather large, elongated utricle. Leaves opposite or scattered, sessile or petiolate, oblong, ovate, or lanceolate, entire. A few of the species are known to cultivation, but they have very little to recommend them to gardeners. Those described below thrive in well-drained loam. Propagation may be easily effected by cuttings, inserted in similar soil.
P. aculeata (prickly). West Indian Cockspur. fl. greenish, in small, dense cymes or globular clusters. March. fr. in loose cymes, often forming large panicles. l. opposite or here and there alternate, petiolate, ovate, often broad, or rarely oblong or lanceolate, obtuse, entire, rarely exceeding 3in., and often less than 2in. long. h. 10ft. Tropics, 1806. A tall, woody, greenhouse climbing shrub, often armed with stout, recurved, axillary prickles.
P. grandis (grand). A synonym of P. inermis.
P. inermis (unarmed). fl. greenish, collected in small cymes, forming a terminal, rather corymbose panicle, usually shortly pedunculate. March. l. petiolate, ovate or oblong, acuminate or almost obtuse, rounded or narrowed at base, often 6in. to 8in. long. h. 10ft. Australia, 1806. A small, greenhouse tree. SYN. P. grandis.
P. obtusata (obtuse). fl. greenish, shortly pedicellate; cymes stalked, terminal. April. l. obovate or obovate-oblong, rounded at the tip, and tapering towards the petiole, glabrous or pubescent. h. 4ft. West Indies, 1824. Stove shrub.