Dawsonia

Dioicous. Aerial stems simple, forked or rarely fastigiately branched, to 65 cm tall, with dense whitish rhizoids at base; central strand with hydroids only or of both hydroids and sclerenchyma. Leaves scale-like at base, larger toward apex, lingulate or linear from a clearly sheathing base, caniculate, plane or spirally twisted, erect-spreading to wide-spreading when moist, appressed when dry, with most of adaxial surface covered with lamellae, except for up to 5 rows of cells along margins; lamellae 2–10 cells tall; apex acute; costa ill-defined, broad; margin serrate, plane or involute; laminal cells rectangular, rectangular or linear in sheath, striate-papillose or smooth. Capsule erect becoming inclined or horizontal when mature, ovoid, 2-angled, flattened or concave dorsally, convex ventrally, with stomata at base. Calyptra cucullate, with a dense mat of entwining branched serrate hairs, initially enveloping entire capsule and sometimes upper seta. Operculum conic. Peristome of numerous long filiform teeth, forming a white or dirty white brush-like tuft, not attached to an epiphragm.