GRASS FAMILY 61 



ows and hillsides: Greenl. — X.H. — -N.M. — Calif. — Alaska; Eurasia. Snhnlp. — 

 Alp. Jl-Au. 



5. T. tnajus (Vasey) Rydb. Cespitose perennial; stems 2-5 dm. liigh, 

 glabrous; leaf-blades 5-15 cm. long, 1-4 mm. wide, usually flat; panicle often 

 interrupted, acute, green, rarely purple, 6-15 cm. long; empty glume lanceolate, 

 acuminate, about () mm. long, usually a little longer than the lemma; awn bent 

 and twisted, 7-8 nun. long. T. suhspicaimn Am. auth., not Beauv. Meadows: 

 Mont.— Colo.— Utah— B.C. Subftwnt.—Suhalp 



35. GRAPHEPHORUM Desv. 



Erect perennials, with short rootstocks. Inflorescence paniculate. Spike- 

 lets 2-4-flowered, flattened, the rachilla hirsute and extending beyond the flow- 

 ers. Emjity glumes 2, somewhat shorter than the lemma, thin-membranous, 

 acute, keeled, shining. Lemma membranous, obscurelj' nerved, entire, some- 

 times short-awned just below the apex, shining; awn straight. Styles distinct; 

 stigmas plumose. 



Empty glumes nearly ecjual: inflorescence narrow. 



Sheaths and upper surface of the leaves pubescent; .spikelets 3-flowerecl. 



1. O. mulicum. 

 Sheaths and leaves scabrous. 



Empty glumes barely equalling the lemma: spikelets 2-flo\vered; rudiment long- 

 hairy. 2. G. Wolfii. 

 Empty glimies longer than the lemma: spikelets 3-4-flo\vered: rudiment short- 

 hairy. 3. G. Brandegei. 

 Empty glumes unequal; inflorescence open. 4. G. Shearii. 



1. G. muticum (Bolander) Greene. Stem 4-S dm. high; leaf-blades 1-4 

 dm. long, 3-6 mm. wide; inflorescence 1-2 dm. long; empty glumes 6-7 mm. 

 long, acute, scabrous on the back; lemma 5-6 mm. long, minutely scabrous; 

 awn very short, or almost none. Trisetum jnudcum Scribn. Meadows: Calif. 

 — Wash. — Mont. Submont -Siibalp. Je-Jl. 



2. G, Wolfii ^'asey. Stem erect from a decumbent base; leaf-blades 5-15 

 cm. long, 1.5-3 mm. wide; panicle 5-10 cm. long, with few branches; empty glumes 

 4-5 mm. long, slightly shorter than the lemma, acuminate; lemma 2-toothed at 

 the apex; awn about 1 mm. long. Moimtain meadows: Colo. Subalp. 



3. G. Brandegei (Scribn.) Rydb. Stem 3-6 dm. high, smooth; leaf-blades 

 1-2 dm. long, 4-8 mm. wide, scabrous on both sides; panicle 1-2 dm. long, more 

 or less interrui)ted; em]>ty glumes scabrous on the keel, 6-7 mm. long; lemma 

 5-6 mm. long, obtusely 2-lobed; awn borne below the apex, often obsolete. Wet 

 meadows: Mont. — Colo. — Cahf. — -Wash. Submont. — Mont. Je-Au. 



4. G. Shearii (Scribn.) Rydb. Stem 5-7 dm. high, minutely pubescent at 

 the nodes; leaf-blades 1-1.5 dm. long, 3-4 mm. wide, minutely scabrous below, 

 smooth above; panicle 1 -2 dm. long; spikelets usuall\- 2-flowered; empty glumes 

 acute; the first 3 mm. long, 1-nerved, lance-subulate, the second 4 mm. long; 

 lemma about 4 mm. long, slightly 2-cleft at the ajjex; awn straight, 1-3 mm. 

 long. Trisetum argenteum Scribn. T. Shearii Scribn. Among rocks: Colo. 

 Mont. Au. 



36. AVENA (Tourn.) L. Oats. 



Annuals or perennials. Inflorescence a contracted or open panicle. Spike- 

 lets usually large, erect or pendulous, usually 2-several-flowered, rarely 1-flowered, 

 the rachilla articulated between the flowers, the lower flowers perfect, the upper 

 ones often stamhiate or wanting. Empty glumes 2, membranous, exceeding or 

 shorter than the lemma, persistent. Lemma 5-9-nerved, rounded on the back, 

 the apex frequently shortly 2-toothed, bearing a dorsal twisted and geniculate 

 awn, the uppier empty ones or those enclosing staminate flowers awnless. Palet 

 2-cleft or 2-toothed, narrow. Stjdes distinct. Grain deeply furrowed, usually 

 pubescent. 



Perennials, with rootstocks; empty glumes 5-12 mm. long; lemma hairy at the base. 

 Empty glumes shorter than the flowers; panicle lax, narrow, and somewhat nodding; 

 plant not tufted. 1. A. striata. 



