BPOROBOLUs GRAMINEiE 723 



lets 1-flowered. Glumes membranaceo-chartaceous, l-nerved or 

 nerveless, not awned but sometimes pointed. Flowers sessile, or 

 with a minute callus, usually longer than the glumes. Palets 

 similar to the glumes in texture, mostly 1- or indistinctly 3-nerved. 

 Stamens 2 or 3. Ovary oblong. Stigmas with simple hairs. 



S. asperifolins Thurber Bot. Cal. ii, 269. Stems 6-15 inches longi 

 branched, decumbent at base, rooting at the nodes and thus forming broad 

 matted tufts: leaves flat, 1-3 inches long, about 1 line broad, scabrous: 

 ligules very short, truncate : sheaths smooth, loose, very short and overlap- 

 ping below: panicle included at base, open,. 3-5 inches long, pyramidal or 

 ovoid, in outline, its scabrous branches solitary or in pairs : spikelets less 

 than a line long, on pedicels 6 lines long : glumes nearly equal, acute, min- 

 utely scabrous : flowers slightly exceeding thf glumes, the flowering glume 

 sometimes with a minute mucro at its obtuse tip. In alkaline soil, Brit. 

 Columbia to California and Nebraska. 



S. cryptandrns Gray Man. ed. 2, 542. Stems 2-3 feet high, usually 

 geniculate and branched below: sheaths smooth, strongly bearded at the 

 throat, the lower shorter than the internodes : ligules reduced to a mere 

 fringe : leaves flat, 3-6 inches long, about 2 lines wide, acuminate, scabrous 

 above : panicle narrowly pyramidal, more or less enclosed by the upper 

 sheath, -1-8 inches long, its 'branches mostly in pairs, spreaditig : spikelets 

 aline long, short-pedicelled, rather crowded, lead-colored: empty glumes 

 somewhat acute, the upper twice the length of the very narrow lower one : 

 flowering glume about equalling the second one. In sandy soil, Oregon to 

 the New England coast. 



8. alroides Torr. Pac. R. Rep. vij, 21. Stems 2-3 feet high, somewhat 

 rigid, smooth, forming large tufts, rarely branched, clothed below with 

 dead sheaths : sheaths smooth, with a few long hairs at the throat, the 

 2 lower overlapping, the uppermost loose: ligules nearly obsolete: leaves 

 very pale, convolute and tapering to a filiform point, the basal ones aboUt 

 half as long as the stems, the uppermost reduced to a mere filiform appeh- 

 dage to the sheath : panicle broadly pyramidal, soon exserted, 6-12 inches 

 lung, few-flowered : its slender branches solitary or in pairs, spreading or 

 reflexed: spikelets a line long, brownish, on rather long pedicels : empty 

 glumes rather obtuse, the first norrower and X-K as long as the second 

 one ; flowering glume slightly longer than the second one : palet about as 

 long as the glume. On prairies, eastern Oregon to California and Nebraska . 



S. cngpldatus Wood Bot. & Fl. 385. Smooth and glabrous: stems 

 1-2 feet high, erect, simple or somewhat branched : sheaths shorter than 

 the internodes: ligule a mere ring: leaves 1-4 inches long, less than 1 line 

 wide, erect, involute-setaceous, at least when dry: panicle 2-5 inches long, 

 slender, its branches }^-l inch long, appressed: spikelets l!^-lj^ lines 

 long: empty glumes acuminate or cuspidate, scabrous on the keel; flower- 

 ing glume long-acuminate and cuspidate, sparingly scabrous. In dry soil, 

 eastern Washington to the Missouri river. 



S. depanperatns Scribn. Bull. Torr. Bot. Club, ix, 103. Vilfa-dep- 

 auperata Torr. Stems tufted, very slender, 3 inches to 2 feet long, decum- 

 bent and geniculate, often much branched: leaves short, often involute, 

 very minutely scabrous above : sh«aths rather loose, crowded and overlap- 

 . ping below : panicle J^-2 inches long, very narrow, ;of few solitary distant 

 erect branches: spikelets 1 line long or less, short-pedicelled: empty 

 glumes ovate, obtuse, nearly equal : flower about twice as long as the emp- 

 ty glumes, often blackish, deciduous ; flowering glume obscurely 3-nerved, 

 the mid-nerve often excurrent as a small mucro: palet n^rly as long as 

 the glume. Oo margins of ponds, eastern Oregon to Oaliforiiia and New 

 Mexico. 



