52 GRAMINEAE (GRASS FAMILY) 



tracted panicles 8-15 cm. long: leaves scabrous, 6-10 cm. long, 1-2 mm. wide: 

 spikelets sessile or pedicellate, 3-4 mm. long: glumes nearly equal in length; 

 the first about one half as long as the lemma, 1-nerved, acute or erose at 

 apex; the second a little longer than the first, 3-nerved and 3-toothed, rarely 

 entire at apex; lemma pubescent or scabrous on the back, ciliate on the mar- 

 gins; awn flexuous, 8-20 mm. long. Colorado and southward. 



la. Muhlenbergia gracilis breviaristata Vasey, Contr. U. S. Nat. Herb. 

 3: 67. 1892. Slender, 15-30 cm. high: panicle about 5 cm. long: awn 2-4 mm. 

 long. Wyoming and southward. 



2. Muhlenbergia filiculmis Vasey, Contr. U. S. Nat. Herb. 1: 267. 1893. 

 Low and tufted, with scape-like culms 15-35 cm. high, short setaceous radical 

 leaves, and narrow spike-like panicles 2-5 cm. long: first glume 1-nerved, 

 1 mm. long; the second 3-nerved, 3-toothed, 5 mm. long; lemma ciliate on the 

 margin of the lower half, 3-nerved, 2.5 mm. long, shading into an awn about 



1 mm. long. Colorado. 



3. Muhlenbergia Wrightii Vasey, Coult. Man. Rocky Mt. Bot. 409. 1885. 

 Erect or decumbent, 30-75 cm. high, with keeled sheaths and densely flowered, 

 cylindrical, spike-like panicles 5-9 cm. long: leaves rigid, 8-12 cm. long, the 

 tips filiform: spikelets often 2-flowered: glumes subequal, 1-nerved, about 



2 mm. long, thin at base, ovate, awn-pointed; lemma a little thicker and 

 longer, very short-pubescent, 3-nerved, ovate, acute, tipped with a very short 

 stiff awn. Colorado and south west ward. 



4. Muhlenbergia racemosa (Michx.) B. S. P. Prel. Cat. N. Y. 67. 1888. 

 Rather stout and upright, 6-9 dm. high, with very tough and densely scaly 

 rootstocks, simple or more or less branched culms, and densely-flowered nar- 

 row panicles 5-10 cm. long: leaves 5-12 cm. long, 2-6 mm. wide, scabrous: 

 spikelets much crowded: glumes of the spikelet acuminate, 4-6 mm. long, in- 

 cluding the awn, smooth or scabrous (especially on the keel) ; lemma one half 

 to two thirds as long, acuminate, the strongly scabrous midrib excurrent in a 

 short point. Throughout our range. 



5. Muhlenbergia comata (Thurb.) Benth. Journ. Linn. Soc. 19: 82. 1881. 

 Either stout or slender, upright, 3-9 dm. high, with flat leaves and densely 

 flowered, more or less lobed or interrupted panicles 8-10 cm. long: leaves 6-12 

 cm. long, 2-4 mm. wide, erect, rough: glumes of the spikelet equal, or the 

 second a little longer, smooth, scabrous on the keel; lemma shorter, smooth 

 and glabrous, bearing an awn 2-3 times its length, the basal hairs silky, erect, 

 fully as long as the scale. Throughout our range and far westward. 



6. Muhlenbergia gracillima Torr. Pac. R. R. Rept. 4 5 : 155. 1857. Densely 

 tufted, with slender culms 2-4 dm. high, numerous involute basal leaves and 

 open capillary panicles 10-20 cm. long: leaves 3-5 cm. long, smooth or 

 somewhat scabrous, secondary branches of the panicle fascicled: spikelets 

 about as long as the filiform pedicels, which are clavate-thickened at the apex: 

 glumes unequal, usually awn-pointed or short-awned, slightly scabrous; 

 lemma 2.5-3 mm. long, longer than the glumes, sometimes twice as long, 

 scabrous; awn 2-4 mm. long. Colorado and southward. 



7. Muhlenbergia pungens Thurb. in Gray, Proc. Acad. Nat. Sci. Phila. 

 1863: 78. Culms 2-4 dm. high, from creeping rootstocks, erect from a decum- 

 bent branching base, rigid, minutely pubescent: leaves 3-5 cm. long, involute- 

 setaceous, rigid, scabrous: panicle open, 7-15 cm. long, the primary branches 

 solitary, much divided from near the base, the divisions apparently fascicled: 

 spikelets on long pedicels which are clavate-thickened at the apex: glumes 

 when mature equaling or often shorter than the body of the lemma, scabrous, 

 especially on the keel; lemma, when mature, 1.5-2 mm. long, scabrous; the 

 awn shorter than its body. Infrequent in our range; south to Texas and 

 Arizona. 



21. LYCURUS H.B.K. TEXAN TIMOTHY 



Caespitose erect or ascending perennials with narrow or often convolute 

 leaves and cylindrical, usually densely flowered, spike-like terminal panicles. 

 Spikelets 1-flowered, usually in pairs. Glumes 2, 3-nerved, the nerves often 



