Herbs, perennial, prostrate, mat-forming; roots stocks stoud; branches rooting at nodes; leaves elliptic or obovate, white villous when young, sparsely hairy beneath, shortly petiolate; flowers in axillary, solitary or 2-3 together, globose or ovoid across sessile heads; bracts persistent, white, membranous; bracteoles slightly smaller than bracts; tepals white, oblong-lanceolate, subequal, outer 2 longer; stamens 5, all fertile, filaments connate at the base, anthers 1-celled; ovary oblong, 1-celled, ovule -1, pendulous, style short, stigma bifid; utricles orbicular-lanceolate, compressed, enclosed within sepals; seeds discoid, brownish, shining.