Plants small to large; subgametangial branching common. Stems yellow-green, brown, or reddish brown; cross section irregularly pentagonal, hyalodermis interrupted or absent, cortical cells in 2-6 layers, small, walls thick, medulla thick, cells large, walls usually thick, central strand prominent; rhizoids smooth or roughened; axillary hairs usually of 5 cells, basal cells 1 or 2, short, walls brown, apical cell elongate, hyaline. Leaves radially arranged or somewhat complanate, lanceolate, linear-lanceolate, oblong-lanceolate, oblong-elliptic, or oblong-ovate; costal abaxial surface shiny, stereid bands 2, guide cells in 1 row or sometimes 2 at base, abaxial and adaxial costal epidermis well developed or not; laminal cell walls collenchymatous or not. Specialized asexual reproduction common, by propagula terminal on leafless stem apices. Sexual condition dioicous or autoicous; perigonia as terminal discoid splash platforms, or budlike and in series down stems of male plants, sometimes below terminal perichaetia, outer and inner leaves dimorphic; perichaetia terminal; paraphyses present or absent, isomorphic or weakly differentiated between female and male plants. Seta usually single, erect or slightly inclined, twisted, smooth. Capsule inclined or horizontal, furrowed; exothecial cells differentially thickened in longitudinal bands; stomata restricted to inconspicuous hypophysis, phaneropore; annulus 2-seriate, revoluble; operculum rostrate, rostrum short or long, usually blunt; peristome diplolepidous, alternate; exostome papillose; endostome well developed, cilia 2-4, often nodose or nodulose. Calyptra cucullate. Spores 8-20 µm, smooth or papillose.