Flora of North America species comparison

leaves triangular, large, less than 1.7 mm, mostly appressed to stem, apex weakly apiculate to narrowly obtuse;

hyaline cells efibrillose and seldom to often septate at base and sides.

leaves 1.1 × 1 mm; rarely hemiisophyllous;

hyaline cells non-ornamented, frequently septate.

unranked, long and tapering, leaves greatly elongate at distal end.

clavate and rounded at distal end.

ovate-lanceolate to lanceolate in aquatic forms, ovate to ovate-lanceolate in emergent forms, greater than 2.5 mm, often falcate-secund, especially in submerged forms, weakly undulate and recurved when dry;

margin entire, hyaline cells on convex surface with 0–1 pores per cell, concave surface with round wall thinnings in the cell apices and angles; chlorophyllous cells narrowly triangular in transverse section and well-enclosed on the concave surface.

broadly ovate, 2.4 × 1.7 mm;

hyaline cells on convex surface with numerous round pores along the commissures, comb-lamellae on hyaline cell walls where overlying chlorophyllous cells; chlorophyllous cells broadly triangular in transverse section and well-enclosed on the convex surface.

dioicous.

dioicous.

with pseudostomata.

22–29 µm; finely papillose on both surfaces;

indistinct triradiate ridge on distal surface;

proximal laesura 0.5–0.6 spore radius.

fascicles with 2 spreading and 2 pendent branches.;

branch stem green, cortex enlarged with conspicuous retort cells.

fascicles with 2 spreading and 2 pendent branches.;

branch stems with hyaline cell comb-lamellae visible on interior cortex wall, cortical cell end walls with conspicuous funnel projections more than 1/2 length of cell, superficial cortical wall aporose.

not seen.