7. Polytrichum Hedw. 金发藓属 jin fa xian shu
Sp. Musc. Frond. 88. 1801.
Plants usually medium-sized to large, sometimes up to 40 cm high, green, dark green or reddish brown, rigid, densely tufted or scattered. Stems simple, rarely branched, often with many rhizoids at base. Leaves straight, erect or slightly crisped when dry, erect-spreading when moist, crowded on upper stems, the lower leaves mostly deciduous; upper leaves lanceolate, often incurved, distinctly sheathing at base; margins entire or serrate, sometimes hyaline; upper leaf cells rounded oval or nearly quadrate, sometimes bistratose, often thick-walled; cells at sheathing base rectangular or narrowly rectangular, unistratose; costa thick, broad, often extending to a filiform acumen, grossly dentate on back; ventral lamellae densely covered on the surface of costa. Mostly dioicous. Male plants small; perigonia in rosettes, often with innovations in the center. Setae elongate, rigid, reddish yellow or reddish brown; capsules usually large, cylindrical or oblong-spherical, sharply 4–6 keeled, apophyses usually present, with stomata at base of urns; exothecial cells sometimes papillose; opercula deciduous, often beaked; annuli differentiated; peristome teeth 32 or 64; membrane thin. Calyptrae cucullate, densely ciliated. Spores mostly spherical, verrucose.