Shrub, 0.3-2 m tall, bushy. Stems spreading; branches 4-lined and flattened at first, eventually terete. Leaves with petiole 2-4 mm long; lamina 25-88 mm long, 10-42 mm broad, ovate to lanceolate or oblong-lanceolate, apex acute or apiculate to rounded, base broadly cuneate to rounded, venation rather densely to scarcely reticulate. Inflorescence of 1(2-7)-flowered sub¬corymbose cymes; flowers 4-7 cm in diameter. Sepals 7-18 mm long or sometimes longer and foliaceous, narrowly elliptic or lanceolate to broadly ovate or very broadly elliptic, acute to apiculate or more rarely obtuse, entire, spreading or ascending in bud and fruit. Petals obovate, 16-30 mm long, 2.5-3 x longer than the stamens. Stamens 60-80 in each fascicle. Ovary 6-7 mm long; styles half as long as the ovary, free, gradually divergent, spreading at apex. Capsule (9-)14-19 mm long, ovoid, without vittae. or vesicles. Seeds 0.7-1 mm long, carinate or slightly winged; testa shallowly linearreticulate.

Fl. Per.: June July.

Type: India; Kumaon, Blinkworth (K!).

Distribution: China (Yunnan) to W. Pakistan.

Cliffs and rocky slopes, 1800-3600 m. This species has frequently been confused with the Indonesian H. leschenaultii Choisy. It is related to H. hookeranum Wight and Arn., from which it differs by the acute to obtuse (not rounded), usually narrower sepals. stamens longer relative to the petals (0.35-0.4 instead of 0.25-0.35), styles longer relative to the ovary (0.5-1 instead of 0.2-0.5), the frequently + densely reticulate leaf-venation, and the 4-lined branches (usually terete in H. hookeranum). It differs from the superficially rather similar H. leschenaultii by the relatively longer stamens and styles (see measurements for H. hookeranum above), longer petiole (2-4 mm instead of up to 2 m.), and the frequently broader sepals and more densely reticulate leaf venation.

* H. choisianum Wall. ex N. Robson, sp. nov.; H. hookerano Wight et Arn. affinis sed sepalis anguste ellipticis vel lanceolatis vel late ovata vel latissime ellipticis apice plerumque acutis vel obtusis, staminibus stylisque pro ratione longioribus, foliorum venatione saepe dense reticulati, differt.