Capsule 2-3 mm, inclined to nearly erect, straight or weakly curved, narrowly tapered to a long slender neck, mouth nearly parallel to the axis of the capsule.

Soil, disturbed habitats such as partially shaded building foundations; low elevations; Ariz., Fla., Ga., La., N.C., S.C., Tenn., Tex.; Mexico; West Indies; Central America; South America; Africa.

Variety calvescens seems to be a tropical expression of the species although it is known from a few southern states in the United States. H. A. Crum and L. E. Anderson (1981) suggested that the name has been misused to the extent that other North American records outside the southeastern United States should be ignored. This variety is apparently widely distributed in tropical latitudes.