1. Ocimum americanum Linnaeus, Cent. Pl. 1, 15. 1755.
灰罗勒 hui luo le
Ocimum africanum Loureiro; O. canum Sims.
Herbs annual, 20-30(-60) cm tall. Stems erect, retrorse puberulent, nodes bristly, much branched from stem base. Petiole 5-12 mm, puberulent and pilose; leaf blade ovate, 1-1.7 cm × 5-10 mm, puberulent, glandular, base cuneate, margin serrulate to subentire, ciliate, apex acute, lateral veins 4- or 5-paired. Racemes numerous, crowded, erect, 10-14 cm, pedunculate, retrorse puberulent; verticillasters separate, 6-flowered; bracts oblong, ca. 4 mm, base attentuate, margin bristly, apex attenuate. Pedicel ca. 1.5 mm, conspicuously recurved in fruit. Calyx campanulate, ca. 2 × 1 mm, puberulent near base, throat densely puberulent, tube ca. 1.5 mm; middle tooth of upper lip circular, lateral teeth shorter, triangular; lower lip teeth ovate-lanceolate, apex awned, longer than upper lip, ciliate; fruiting calyx ca. 4 mm, conspicuously 10-veined. Corolla straight, 1.5-2 × as long as calyx, limb sparsely puberulent, glabrous inside; tube conspicuously exserted, obconical; lower lip oblong, concave, margin entire. Stamens free, ca. 2 × as long as corolla. Nutlets black, ovoid, ca. 1.5 × 0.6 mm, finely dotted.
Yunnan [India, Indonesia, Malaysia, Myanmar, Philippines, Sri Lanka; Africa, SW Asia]
Leaves are made into a paste which is used for skin diseases.