Order 11. Polytrichaceæ. Single peristome, formed by 16, 32, or 64 teeth. Leaves with longitudinal lamellæ on upper surface.—Polytrichum has long, hairy calyptra. Catharinea (C. undulata, in forests).
Order 12. Georgiaceæ. Peristome with 4 teeth (see above). Tetraphis (T. pellucida has gemmæ).
Order 13. Buxbaumiaceæ. Capsule asymmetrical; double peristome: the interior one conical, with 16 or 32 longitudinal folds.—Buxbaumia (B. aphylla); Diphyscium.
B. Pleurocarpi.
Order 14. Fontinalaceæ. Long, floating Water-Mosses. Fontinalis (F. antipyretica is found in streams). Dichelyma.
Order 15. Hookeriaceæ. Pterygophyllum.
Order 16. Leskeaceæ. Dull-looking Mosses, with papillose or warted leaves.—Thuidium, Thuja-like with regularly arranged 1–3 doubly pinnate stems; Anomodon, Leskea.
Order 17. Pterogoniaceæ. Pterigynandrum filiforme, etc.
Order 18. Fabroniaceæ. Anacamptodon.
Order 19. Neckeraceæ. Stems most frequently with flat, leafy branches. The leaves are smooth, never with longitudinal folds.—Neckera.