Ceylon slitwort

Description

The plant grows to a height of up to 120 cm (47 in). Stipules are absent, the taproot is white or brown, and the stem is quadrangular. Sub-sessile leaves are linear-lanceolate or elliptic-lanceolate, 2.5–7.5 cm (0.98–2.95 in) long, not lobed or divided, blunt at the tip, obtuse, entire or cerrulate, glandular, hispid and coarsely dentate at the margins. Whorls of many flowers are bisexual, sessile or sub-sessile, usually in terminal whorls 1–2 cm (0.39–0.79 in) in diameter, grouped together in an axillary, corolla white in color and 2 cm long. Calyx is 5–7 mm (0.20–0.28 in) long, and obliquely turbinate, with minute teeth, apex acute, base acute, pinnately veined, erect or spreading horizontally. It is reproduced by seed and pollinated by bees moths and flies. Leucas belongs to the subfamily Lamioideae, and is closely related to the small genera Acrotome and Leonotis.