Calamagrostis cainii Hitchc.

Calamagrostis cainii Hitchc. Jour. Wash. Acad. 24: 480. 1934
Culms slender, erect, scabrous below the panicle, 30-40 cm. tall; sheaths glabrous; ligule of culm-leaves thin, rounded or obtuse, finely dentate, becoming lacerate, 1-2 mm. long; blades erect, flat, more or less involute toward the finely attenuate tip, glabrous beneath, scaberulous on the upper surface, narrowed toward base, the basal ones as much as 35 cm. long, 1-2 mm. wide, the uppermost culm-blade 5-10 cm. long, about 1 mm. wide; panicle pale or whitish, loose, 6-10 cm. long, the axis scabrous, the branches ascending or somewhat spreading, verticillate, scabrous, 1-2 cm. long, bearing 1-few spikelets, the whorls 7-15 mm. apart, the pedicels scabrous-pubescent; glumes narrow, nearly equal, acuminate or slightly aristate, glabrous except the scabrous upper half of the keels, 5-6 mm. long, the first 1-nerved, the second 3nerved; lemma narrow, acuminate, 5-nerved, glabrous below, minutely scaberulous near the finely toothed summit, the callus-hairs about 1 mm. long, the awn about 1 mm. from base, somewhat geniculate, twisted below, the tip bent to one side and somewhat exceeding the glumes; palea a little shorter than the lemma; prolongation of the rachilla very short but the hairs 1-2 mm. long.
Type locality: Summit of Mount LeConte, Tennessee, alt. about 2000 m. (Cain 48). Distribution: Known only from the type locality.