Bryidae

Subclass Bryidae Sporophyte may have elongate seta, with or without conducting strand; sporangium diverse in form, with internal cylindric columella encircled by spore-bearing layer, usually opening by operculum to expose articulated peristome teeth in 1 or 2 concentric circles; peristome teeth pulsating in response to moisture…

The large subclass Bryidae constitutes most species of mosses, but the subclass Polytrichidae also has some important members. Other, smaller subclasses are represented by only a few species.