Orthosiphon
(from orthos, straight, and siphon, a curved tube; alluding to the tube of the flower). ORD. Labiatae. A genus comprising about sixteen species of stove or greenhouse perennial herbs, sub-shrubs, or rarely shrubs, mostly natives of the East Indies and the Malayan Archipelago, two or three being found in tropical Africa, and one extending from Malaya into Australia. Flowers pedicellate, slender, or showy; corolla tube exserted; limb bilabiate; stamens four; whorls commonly six, rarely two to four-flowered, in often elongated, distant, or rarely crowded racemes. The undermentioned (probably the only species in cultivation) thrive in a compost of sandy loam and fibry peat. Propagated by cuttings, made of half-ripened shoots. O. incurvus (incurved). fl. pale scarlet; corolla villous, incurved, thrice as long as the calyx; lip spreading; whorls sub-secund. May. l. petiolate, ovate or oblong, crenate, pubescent. Stem procumbent at base, ascendent. h. 1ft. Eastern India, 1839. Stove evergreen. (B. 173; B. M. 3847.) O. stamineus (long-stamened).* fl. pale lilac-blue, nearly 1in. long, very numerous, arranged in whorls, and these again in racemes at the ends of the branches; stamens projecting a long way. July. l. ovate or deltold, coarsely and irregularly toothed, glaucous below. Stem herbaceous, erect. h. 2ft. Tropical Asia, &c., 1869. Stove. (B. M. 5833.)