Fragilegrass

Aegopogon unisetus (Lag.) R. & S. Syst. Veg. 2 : 805. 1817
Hymenothecium uniseium I^ag. Gen. Sp. PI. 4. 1816.
Schellingia tenera Steud. Flora 33 : 232. 1850.
Aegopogon geminiflorus "BoVim. Mex. PI. Gram. 71. 1881. '^ot A. geminiflorus '^.'^.'K,. 1815.
Aegopogon geminiflorus purpureus Qris^h.; Fourn. Mex. PI. Gram. 71. 1881.
Aegopogon gem.iniflorus unisetus Fourn. Mex. PI. Gram. 71. 1881.
Aegopogon geminiflorus aboriivusVoyxrrs.. Mex. PL Gram. 71. 1881.
Stems up to 5 dm. long, slender; leaf -sheaths smooth and glabrous; blades usually 1-6 cm. long, rarely 1 dm., 1-3 mm. wide, glabrous -beneath, commonly puberulent on the upper surface or rarely glabrous and scabrous; inflorescence 2-6 cm. long, often interrupted below; spikelet-clusters 3-4 mm. long, exclusive of the awns and the hispid peduncle, of 3 spikelets on hispid pedicels, the sessile or short-pedicellate spikelet perfect, the others empty; empty scales obovate, obovate-cuneate, or cuneate, 2-lobed at the apex with rounded or truncate lobes, 1-nerved, rarely awnless, the nerve usually extending a^ a hispidulous awn shorter than the scale, or rarely equaling it; flowering scale of the perfect spikelet 3-nerved, 3-lobed and 3-awned at the apex, the midnerve running out into a hispidulous awn usually longer than the spikelet, rarely shorter, the lateral lobes subulate and extending into short awns, and sometimes with a minute tooth at the base of the awn, the lobes rarely obtuse and merely awn-pointed, the flowering scale of the other spikelets with the lobes rounded and muticous, rarely awn-pointed, or the lobes rarely resembling those of the perfect spikelet.
Type locality : Mexico. Distribution : Arizona to Guatemala.

Aegopogon imperfectus Nash, sp. nov
Stems up to 2 dm. long, very slender; leaf-sheaths smooth and glabrous; blades 1-4 cm. long, up to 1 mm. wide, glabrous beneath, puberulent on the upper surface; inflorescence 3-4 cm. long; spikelet-clusters 2-2.5 mm. long, exclusive of the pedtmcle, of 2 spikelets, one perfect, the other rudimentary, or sometimes a third spikelet present consisting of a pedicel and a minute scale; empty scales of the perfect spikelet 1-nerved,, lanceolate and acute, or rarely obscurely 2-toothed and shortly awned, those of the other spikelets very small and often rudimentary; flowering scale of the perfect spikelet 3-nerved, 3-toothed at the apex, the nerves sometimes slightly excurrent, the flowering scale of the other spikelets rudimentary.
Type collected on cool mossy ledges, Arroyo Aucho, Sierra Madre, Chihuahua, Mexico, October 15, 1887, C. G. Pringlel408 (herb. Columbia Univ.). Distribution : Known only from the type locality.