An evergreen shrub closely related to R. pachytrichum, of sturdy, bushy habit and probably capable of growing io ft or more high. It differs chiefly from R. pachytrichum in the young shoots and leaf-stalks being furnished with straight, unbranched, gland-tipped bristles; in R. pachytrichum the hairs are curly, branched and not gland-tipped. Leaves oblong, 3 to 6 in. long, 1 to 11⁄2 in. wide, green on both surfaces and glabrous except for some hairs at the base of the midrib. Flowers produced in April, a dozen or so together, in hemispherical terminal trusses 4 in. wide. Calyx and flower-stalk glandular. Corolla bell-shaped, 11⁄4 in. wide, white tinged with rose, marked at the base with a black-purple blotch and a few spots. Stamens ten, white, downy at the base; anthers dark purple. Ovary covered with short glands, mixed with longer whitish hairs, style glabrous. Bot. Mag., t. 8675. (s. Barbatum ss. Maculiferum)
R. monosematum was found by Wilson on the Wa Shan, W. Szechwan, in 1903, and was described from a cultivated plant, raised from the seeds which he sent to Messrs Veitch. It will be seen from the description given above that it differs from R. pachytrichum in the glandular character of the hairs on branchlet, leafstalk, flower-stalk, calyx, and ovary. It has about the same hardiness and the same garden value.
From the Supplement (Vol. V)
Included in R. pachytrichum, q.v. in this supplement.