Capsule facultatively cleistocarpous: annulus differentiated but operculum remains attached, spores released through ruptured capsule walls.

Capsules mature July. Grassland soil; 950 m; Nebr.

This taxon is P . subsessile with possibly hybrid sporophytes. Two forms with identical gametophytes were present in the type collection, one with typical sporophyte, the other with that of the variety. The operculum is not dehiscent and the capsule bursts irregularly. The sporophyte apparently falls as a unit, breaking off at the base of the seta. The single collection is from Nebraska, Chase Co., 12.5 km W of Champion, W. Kiener 10627 (MO).