| + | Ceratostigma differs from Plumbago in having no glands on the calyx, stamens adnate to the corolla tube, fls. in dense clusters rather than spicate, and other technical characters: lvs. alternate, lanceolate or obovate, more or less ciliate: fls. mostly in terminal heads, blue or rose; calyx tubular, deeply 5-parted, the lobes narrow; corolla salver-shaped, the tube long and slender, the limb spreading and with 5 obovate obtuse or retuse lobes; stamens 5, attached on the corolla tube: fr. a 5-valved caps, inclosed in the calyx. — Species 4 or 5, in N. China, Himalayas, Abyssinia. |