Flora of North America species comparison

leaves lingulate-triangular to lingulate, 1–1.4 mm, apex broadly rounded but becoming acute in hemiisophyllous forms, border strongly developed at base (more than 0.25 width);

hyaline cells rhombic and 0–3-septate with some cells in leaf midregion 2–septate.

weakly to strongly 5-ranked.

usually of two distinctly different types;

branch leaves that are normally inrolled and broadest ca. 1/4–1/3 the distance from the base, more or less tapered to a cucullate to involute apex;

stem leaves more or less flat and usually broadest at the base;

both leaf types of a network of hyaline, dead cells and green chlorophyllose cells;

pores and reinforcing fibrils frequent in branch leaf hyaline cells and uncommon in stem leaf hyaline cells.

ovate to ovate-lanceolate, 0.9–1.2 mm, concave, subsecund on some branches, apex involute;

hyaline cells on convex surface with numerous round to elliptic pores along the commissures, grading from small round pores near apex to round pores near base, on concave surface with large round pores in proximal portions of leaf.

dioicous.

18–33 µm, coarsely papillose on both surfaces;

proximal laesura less than 0.4 spore radius.

released by explosive opening of operculum.

fascicles with 2 spreading and 1–2 pendent branches.

thallose.

lacking.

consisting of a spherical capsule with pseudostomata on capsule surface, a very short seta, and a foot, exserted on a pseudopodium of gametophyte tissue.