Roella
(named in honour of William Roell, Professor of Anatomy at Amsterdam). ORD. Campanulaceoe. A genus comprising eleven species of greenhouse, rigid sub-shrubs or small, diffuse herbs, confined to South Africa. Flowers sessile within the imbricating leaves, solitary or glomerate; calyx with an adnate, oblong or cylindrical tube and a five-parted limb, the lobes often toothed; corolla campanulate or funnel-shaped, five-lobed. Leaves scattered, small or narrow, often rather rigid and fascicled at the axils, entire or ciliate-toothed. Several of the species have been introduced, but that described below is the most desirable. A compost of sandy loam and peat is most suitable for its culture. Propagation may be effected by seeds; or by young cuttings, which will root freely in the soil above-named, if a hand glass be placed over them.
R. ciliata (ciliated-leaved). African Harebell. fl. solitary, terminal; corolla white at base, with a deep purple circle, above pale violet, girded by white, the lobes rose-coloured. September. l. erect, linear, acuminated, ciliated; upper ones longer. h. 6in. to 12in. 1774. (B. M. 378; F. d. S. 517; L. B. C. 1156.)