Rhizomes obvious. Cauline stems terete, without spots, 10--80 cm. Turions present, in axils of old leaves and from disintegrating branches, fusiform, 0.7--2 cm, leaves spreading to ascending. Leaves submersed, ± spirally arranged, flaccid, sessile; stipules deliquescent, inconspicuous, convolute, free from blade, pale green, not ligulate, 0.5--1.2 cm, not fibrous, not shredding at tip, apex obtuse; blade pale green, linear, not arcuate, 1.8--6.5 cm ´ 0.1--0.5 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, extremely attenuate, bristly, lacunae present, each side of midvein to margins; veins 1. Inflorescences unbranched, emersed; peduncles not dimorphic, terminal, ascending, somewhat clavate, (3--)5--25 cm; spikes not dimorphic, capitate, 5--12 mm. Fruits sessile, light green, round-obovoid or nearly orbicular, compressed, abaxially and laterally keeled, 2--3 ´ 1.7--2.8 mm, lateral keels without sharp point; beak erect, 0.5 mm; sides without basal tubercles; embryo with less than 1 full spiral. Chromosome number apparently unknown not available.
More
Stems 1–8 dm, slender and delicate, repeatedly branched; rhizome elongate; lvs numerous, all submersed, very soft and delicate, flat, 2–5 cm × 0.25 mm, tapering to a hair-like tip, 1-nerved, the space from the midrib to the margin entirely lacunar; stipular sheaths axillary, obtuse, 1–5 cm, seldom longer, evanescent; winter-buds fusiform, 1–2 cm; peduncles usually solitary and terminal below, (3–)5–25 cm, slender below, somewhat clavate; spike capitate, few-fld, 5–12 mm; achenes turgid, broadly obovoid, 2–3 mm, with a sharp dorsal keel flanked by a pair of more obscure ones. Shallow, acid waters; Nf. to Pa., N.J., and Mich.
Home
