An evergreen shrub or small tree up to 15 ft high; young shoots scaly. Leaves scattered along the branches, aromatic, elliptic or oblong-elliptic or broadest slightly above or below the middle, apex varying from obtuse to acute or acuminate, base rounded or broadly tapered, I to 31⁄2 in. long, 1⁄2 to 13⁄8 in. wide, dark green or glaucous green and scaly above, pale brown to dark brown beneath from the densely arranged scales; stalk up to 3⁄8 in. long. Flowers in terminal trusses of two to eight, opening in May. Calyx very variable, reduced to a rim or with five rounded or pointed lobes, scaly at least on the margin, sometimes fringed with hairs. Corolla five-lobed, widely funnel-shaped, coloured in some shade of purple or reddish purple, occasionally white, usually spotted with brown or crimson, scaly on the outside, rarely without scales, glabrous or slightly hairy towards the base. Stamens ten, hairy at the base. Ovary densely scaly; style glabrous or slightly hairy at the base. Bot. Mag., tt. 8280, 8912. (s. Triflorum ss. Yunnanense)
Native of W. Szechwan; discovered by the Rev. Ernst Faber on Mt Omei; introduced by Wilson in 1904. It is a variable species in leaf-shape, calyx, colour of flowers, etc. It is perfectly hardy but now little cultivated except for the variety previously known as R. pseudoyanthinum (see below). The following varieties are recognised by Davidian in his revision of the Triflorum series:
var. benthamianum (Hemsl.) Davidian R. benthamianum Hemsl. – Flowers lavender-purple. Scales of leaf-undersides dissimilar, some dark brown, others yellowish brown. Described from a plant raised by Messrs Veitch from the seeds sent by Wilson.
var. pseudoyanthinum (Hutch.) Davidian R. pseudoyanthinum Hutch. – Flowers deep reddish magenta. Leaves larger than normal. This was raised by Messrs Veitch from Wilson’s seeds and is figured in Bot. Mag., t. 8620, as R. concinnum. The colour of the flowers is arresting but not beautiful.
R. amesiae Rehd. & Wils. – Very closely allied to R. concinnum, the distinguishing character being the bristly leaf-stalk and the often ciliate calyx. Bot. Mag., t. 9221. It has about the same decorative value as R. concinnum but is rare in cultivation. Introduced by Wilson from W. Szechwan in 191 o, during his second expedition for the Arnold Arboretum, under W.4233 (from woodlands near Mupin).
R. polylepis Franch. R. harrovianum Hemsl. – An inferior species allied to R. concinnum, differing in the relatively narrower leaves (up to 4 in. long and 11⁄2 in. wide), more densely scaly beneath, the scales mostly contiguous or overlapping. Bot. Mag., t. 8309.