Straggling or climbing, subscandent herbs or undershrubs, hoary tomentose; stem woody below branches striate, young parts densely pubescent, older ones glabrous; leaves mostly alternate, sometimes opposite, soft, green, elliptic, oblong or rounded, obtuse or acute; flowers bisexual, densely white, villous in terminal or axillary, globose, shortly cylindric, woolly, shining spike; bracteoles ovate, acute, shorter than the perianth, tepals 5, sepaloid, lanceolate; stamens 4-5, connate below, filaments unequal, staminodes interposed, alternately; anthers 2-celled; ovary 1-celled, ovoid or subglobose, glabrous, style short, stigma, minute capitate; urticle indehiscent or circumciss; seeds reniform, coriaceous, shining black.