Creeping, (?) perennial herb 30 cm. long or longer. Main stem 4-gonous, up to 4 mrn. thick, with internodes 8–25 mm. long, rooting at the nodes and sending up erect shoots c. 13 cm. high. Leaves of the creeping stem 9–20 × 4–8 mm., opposite, ovate-lanceolate, subacute at the apex, margin entire, rounded or slightly cordate at the base, penninerved, midrib impressed above, prominent beneath; leaves of the erect shoots decussate or 3-nate, similar to those of the creeping stem but smaller (from 4 × 1 mm. to 10 × 4 mm.), densely crowded towards the end of the stem. Flowers 3-merous, solitary, axillary, scattered along the erect shoots; bracteoles as long as the calyx-tube (c. 1·25 mm.), linear, scarious. Calyx c. 1·5 mm. long, campanulate; lobes c. 0·6 mm. broad and 0·35 mm. high; appendages c. 0·75 mm. long, ± curved. Petals 3, c. 0·5 × 0·3 mm., elliptic. Stamens 3, opposite the calyx-lobes, inserted at the middle of the calyx-tube, reaching the apex of the calyx-lobes; anthers c. 0·25 mm. long. Ovary stipitate, subglobose, c. 1 × 0·75 mm., 3-locular; style (and stigma) c. 0·25 mm. long. Capsule subglobose, c. 1·5 × 1·25 mm., 3-valved, scarcely exserted. Seeds many, c. 0·5 mm. long, whitish, concave on one side, convex on the other.