6. Campylium (Sull.) Mitt. 细湿藓属 xi shi xian shu
J. Linn. Soc., Bot. 12: 631. 1869. Hypnum subgen. Campylium (Sull.) Waldh., Bull. Soc. Imp. Naturalistes Moscou 37(2): 37. 1864. Hypnum sect. Campylium Sull. in Gray, Manual (ed. 2) 677. 1856.
Plants minute to small, often slender, green or yellowish. Stems prostrate, irregularly or regularly branched; in cross section cortical cells in 1–2 layers, thick-walled; central strand weakly differentiated; pseudoparaphyllia small, foliose, lanceolate or triangular; rhizoids sometimes present on costae. Stem leaves erect or squarrose, 1.0–3.0 mm × 0.4–0.6 mm, gradually acuminate, from ovate-cordate or broadly triangular leaf base to a long apex, sometimes involute, squarrose or often reflexed at apex; margins plane, serrulate; costae single or forked, short or lacking; median leaf cells linear, 20–40 μm × 5–7 μm; alar cells often distinctly differentiated, hyaline, enlarged, rectangular. Autoicous. Inner perichaetial leaves lanceolate, plicate; costae single, strong, reaching 1/2 the leaf length. Setae reddish, elongate; capsules horizontal, ellipsoidal; mouth constricted when dry; exothecial cells quadrate to rectangular; exostome teeth cross-striate below, papillose above; cilia 1–4, as long as the segments, nodulose. Spores 10–24 mm in diameter, papillose.