Flora of North America species comparison

green to dark brown, superficial cortex of 0–3 layers of efibrillose, non-ornamented, enlarged, thin-walled cells;

cells in outer layer aporose or with single round to elliptical wall thinning adjacent to the distal cell wall, visible only with heavy staining.;

stem leaves varying from smaller than to larger than branch leaves;

triangular, ovate to lingulate;

with rounded and sometimes erose apex;

border entire;

hyaline cells rhomboid to S-shaped, non-ornamented, efibrillose to fibrillose, aporose to sometimes porose, non- to multiply septate;

neither surface resorbed.

leaves triangular-lingulate, 0.8 mm or less;

apex entire or weakly denticulate, hyaline cells sometimes septate, efibrillose and aporose except near apex.

not always clearly dimorphic, spreading and pendent branches very similar.

often short and blunt.

oval, ovate or ovate-lanceolate;

hyaline cells fibrillose, non-ornamented;

convex surface mostly with numerous elliptical to round pores (8–24 per cell) in rows along commissures on convex surface, concave surface with fewer or no pores; chlorophyllous cells elliptical in transverse section, ± equally exposed on both surfaces or slightly more on convex surface, end walls not thickened.

dioicous.

dioicous.

with few pseudostomata.

exserted, with few pseudostomata.

22–41 µm, with or without raised surface sculpture on distal surface;

proximal laesura more than 0.5 spore radius.

30–35 µm; finely papillose on both surfaces, distinct bifurcated Y-mark sculpture on distal surface;

proximal laesurae more than 0.5 spore radius.

fascicles 1–3 spreading and 0–2(–4) pendent.;

branch stems green, surrounded by 1 layer of efibrillose, non-ornamented, thin-walled, inflated cells, with solitary short-necked retort cells or with conspicuously necked retort cells, interspersed with primarily aporose rectangular-shaped cells.

fascicles with 2–3 spreading and 2–3 pendent branches Branch leaves broadly ovate, subsecund, hyaline cells on convex surface with very numerous small pores (18–40 per cell) in a continuous row along the commissures, concave surface usually aporose.