22. Ptilium De Not. 毛梳藓属 mao shu xian shu
Cronac. Briol. Ital. 2: 17. 1867. Hypnum sect. Ptilium Sull., Manual (ed. 2) 673. 1856, nom. illeg.
Plants robust, large, stiff, yellowish green or pale green, glossy. Stems and branches flattened, densely pinnately branched, branches shorter and shorter toward the stem apices, attenuate at apex, circinate; pseudoparaphyllia numerous, narrowly lanceolate. Leaves dense, stem and branch leaves dimorphic; stem leaves broadly ovate at base, gradually lanceolate, usually deeply plicate and strongly reflexed or curled; margins plane, serrulate above; costae double, short, weak or absent; leaf cells linear, smooth, basal cells shorter and broader, thick-walled, distinctly porose; alar cells distinctly differentiated, quadrate or shortly rhombic; branch leaves narrowly ovate-lanceolate, deeply plicate, falcate-secund, costae not distinct. Dioicous. Perichaetial leaves erect, deeply plicate. Setae slender, reddish brown; capsules inclined to horizontal, oblong-ovoid, arcuate when dry; opercula conic, shortly rostrate; annuli differentiated, 1–2 rows; peristome hypnoid. Spores green, minutely papillose.