Herbs or undershrub, stems somewhat-4 angled, much branched; leaves opposite, elliptic, obtuse at apex, base decurrent, toothed or serrete, glabrous; flowers in 8-12 cm long, terminal, nearly continuous, slender spikes; bracts lanceolate, long or short, bracteoles absent; calyx, 4-toothed, oblique, glabrous; corolla deep blue, tube cylindric, slightly curved, hairy, limbs 5, oblique, spreading; stamens-2, fertile, included, anthers 2-celled, vertically divaricate, cells ovate; ovary 2-locular, 1-2 ovules in each locule, style short, linear, stigma subcapitate; fruits drupe of 2-pyrenes, oblong or pyriform, 1-seeded.