GRASS FAMILY 49 



like, 2-5 cm. long; branches short, erect; first empty glume thin, ovate, acute, 1.5 

 mm. long, the second slightly longer; lemma lanceolate, sparsely pubescent 

 below, 2 mm. long. Mountains: Colo. Mont. Jl-Au. 



20. M. gracillima Torr Cespitose perennial; stems 1-4 dni. high, erect, 

 or decumbent at the base; leaves mostly basal; leaf-blades involute-setaceousj 

 somewhat scabrous; panicle 5-20 cm. long, open; empty glumes unequal, the 

 first about 1.5 mm., the second 2 mm. long, awn-pointed; lemma 2.5-3 mm. 

 long, scabrous; awn 2-4 mm. long. Rixg Grass. Plains and foot-hills : Tex — 

 Ivans.— Colo.— X.M. Plain—Mont. Jl-0. 



21. M. pungens Thurb. Perennial, with a cespitose, creeping rootstoek; 

 stems decmnbent at the base, 1.5-4 dm. high; leaf-blades 2. .5-5 cm. long, involute, 

 rigid, scabrous; panicle 7-15 cm. long, open, its branches 5-7 cm. long; outer 

 glumes 2-2.0 mm. long, purplish, scabrous; lemma 3-4 mm. long, scabrous; awn 

 short. Purple Hair-grass, Blow-out Grass. Sand hills and bad-lands : Tex. 

 — Xeb. — Utah — Ariz. Plain — Mont. Jl-Au. 



22. M. Porteri Scribn. Cespitose perennial; stems geniculate, decumbent, 

 branching: leaf-blades usually flat, 3-5 cm. long, about 6 mm. wide, acimiinate, 

 scabrous above; panicle 7-10 cm. long, about 5 cm. wide; empt.v glumes narrowly 

 lanceolate, 2-2.5 mm. long, purplish; lemma without the avra 3.5-4 mm. long, 

 purple, pilose; awn 5-10 mm. long. M. texana Thurb., not Bucklev. Mes- 

 QUiTE Grass. Hills and plains: Tex. — Colo. — Cahf.; Mex. Son. Au-0. 



22. LYCURUS H.B.K. Texas Timothy. 



Cespitose perennials. Panicle dense, spike-hke. Spikelets 1-flowered, usually 

 in pairs. Empty glumes 2, often awned, 3-nerved. Lemma 3-nerved, awned. 

 Palet smaller, 2-nerved and 2-keeled. Stamens 3. Styles distinct, short; 

 stigmas plumose. Grain free, included in the lemma. 



1. L. phleoides H.B.K. Tufted perennial; stems decumbent at the base, 

 2-5 dm. high, compressed: leaf-blades scabrous above, 4-7 cm. long, 3 mm. wide; 

 spike cyhndric, dense, 4-10 cm. long, .5-S mm. thick; first glume 1.5 mm. long, 

 with 2 a\\-ns, 2-3 mm. long: second glume with an awn 4 mm. long; lemma lance- 

 elliptic, 3 mm. long, pubescent on the back; aw^l 2-3 mm. long. Hills: Tex. — 

 Colo. — Ariz.; Mex. Soti. — Suhmont. Au — -O. 



23. PHLEUM L. Timothy. 



Annuals or perennials. Inflorescence a dense spike-like panicle. Spikelets 

 1-flowered, compressed; flower perfect. Empty glumes 2, persistent, compressed, 

 keeled, obUque at the summit, awned. Lemma shorter, membranous, truncate, 

 denticulate. Styles distinct, long; stigmas sub-plmnose. Grain free. 



Spikes usually elongated-cylindric ; awns less than one-half the length of the outer glumes. 

 „ ., , 1- P- pratfnse. 



Spikes short, ovoid or oblong; awns about one-half the length of the outer glumes. 



2. P. alpinum. 



P. pratense L. Short-lived perennial, with a bulbiform thickened base; 

 stem erect, glabrous and smooth, 3-15 dm. high; sheaths often exceeding the 

 internodes, the upper long and close; leaf-blades 7-20 cm. long, 4-6 mm. wide, 

 usually somewhat scabrous; spike 3-20 cm. long, 5-8 mm. thick; outer ghunes 

 3-4 mm. long, ciliate on the keel; awns about 1 mm long. Meadows; native but 

 also often escaped from cultivation: X.S.^Fla. — Calif. — B.C.; Eurasia. Plain 

 — Subalp. ,Ie-0. 



2. P. alpinum L. Short-Uved perennial; stem 1-5 dm. high, erect or some- 

 times decumbent at the base, smooth; sheaths often shorter than the internodes, 

 the upper usually inflated; leaf-blades scabroiLs above, 2-7 cm. long, 3-S mm. 

 wide; spike 1-5 cm. long, 6-12 mm. thick; outer glumes 3 mm. long, strongly 

 ciHate on the keel; a^Tis 1.5-2 mm. long. Wet places: Lab. — -X.H. — S.D.— 

 N.M. — Calif.— Alaska; Eurasia. Mont. — Alp. Je-S. 



