2. Fontinalis Hedw. 水藓属 shui xian shu
Sp. Musc. Frond. 298. 1801. Pilotrichum sect. Fontinalis (Hedw.) Müll. Hal., Syn. Musc. Frond. 2: 148. 1850.
Plants slender, elongate, dark green, not or slightly glossy, in loose or dense mats. Stems simple below, irregularly branched or nearly pinnately branched above. Leaves arranged in 3 ranks, erect, obliquely patent or falcate, broadly ovate to narrowly ovate-lanceolate, obtuse, acute, short to long acuminate, nearly plane to strongly keeled, concave, sometimes cucullate at the apex, more or less decurrent, rarely auriculate at the base; margins entire, or serrulate at the apex; costae none; upper leaf cells oblong-hexagonal to linear, smooth; basal cells broader and shorter, porose and colored; alar cells sometimes distinctly differentiated. Dioicous. Perichaetia at the apex of short branches or main branches. Inner perichaetial leaves sheathing at the base. Setae very short; capsules immersed, ovoid, erect, symmetrical, smooth; opercula conic, shortly rostrate; annuli not differentiated; peristome double; exostome teeth 16, narrowly lanceolate, dark red or yellowish brown, mostly coarsely papillose, sometimes shorter than the endostome segments, or joined in pairs at the apex, keeled, perforate; endostome segments linear, yellowish brown. Calyptrae mitrate. Spores spherical, green, smooth or finely papillose.