Amphiasma Bremek.

Perennial herbs or subshrubs, with rather strict rush-like stems, usually glabrous or glabrescent. Leaves sessile, opposite; blades linear or filiform, rather rigid and usually erect or nearly so, acute and hard-pointed, the margins revolute; stipule-sheath mostly tubular, truncate or sometimes with 2 small cusps. Flowers 4-merous, isostylous or heterostylous, in small rather dense terminal and axillary capituliform, umbelliform or cymose inflorescences, sometimes combining to form a more ample inflorescence; bracts connate in pairs. Calyx-lobes triangular. Corolla mostly white; tube cylindrical or somewhat funnel-shaped; throat ± densely hairy; lobes ovate or ovate-oblong, hairy in lower half inside. Stamens included in the tube in long-styled flowers, exserted in isostylous and short-styled flowers; filaments glabrous; anthers dorsifixed. Ovary 2-locular; ovules fairly numerous on peltate slightly stipitate placentas affixed just below the middle of the septum; style glabrous, included in short-styled flowers, exserted in long-styled and isostylous flowers; stigma-lobes filiform, densely covered with long papillae. Disc cushion-shaped, farinose. Capsule globose, only slightly beaked, the beak dehiscing loculicidally. Seeds dark brown, not very numerous, dorsiventrally compressed, oblong, smooth.