94 POACEAE 



long, short-awned or awn-pointed; lemma 10-13 mm. lortg, scabrous on the 

 margins. A. unilaterale. Cassidy, not Beaiiv. Scarcely distinct from A. caninum 

 L. of Eu. Meadows and among bushes: Sask. — Minn. — Iowa — N.M. — B.C. 

 Plain — Mont. Je-S. 



8. A. caninoides (Ramaley) Beal. Stem 3-10 dm. high; leaf-blades 1.5-3 

 dm. long, 3 mm. wide, erect, involute or nearly flat; spike 1-2 dm. long, dense; 

 spikelets 1-2 cm. long, pale or purple-tinged; empty glumes 7-9 mm. long, 

 short-awned or awn-pointed; lemma 7 mm. long, scabrous .4. caninum Am. 

 auth., mostly. Mountain meadows; N.S. — Mich.^^N.M. — Calif.— Mont. Mont. 

 — Suhalp. Jl-Au. 



9. A. andinum (Scribn. & Smith) Rydb. Stems 2-3.5 dm. high; leaf-blades 

 2-10 cm. long, 2-4 mm. wide, flat, glabrous beneath, pilose above; spike 3-8 cm. 

 long; empty glumes 8-10 mm. long; lemma 8-10 mm. long, puberulent or glabrate; 

 awn 4-10 nun. long. High mountains: Mont.-^Colo. Mont. — Subalp. Jl-Au. 



10. A. latiglume (Scribn. & Smith) Rydb. Stems 2-4 dm. high, erect or 

 often decumbent at the base; leaf-blades 3-10 cm. long, 2-4 mm. wide, flat, or 

 involute when dry, pubescent on both sides or sometimes glabrate; spike 3-5 cm. 

 long; s]Mkelets 3-5-flowered; lemma oblanceolate, acute or short-awned. High 

 mountains: Alta. — Mont. — -Alaska. Subalp. — -Alp. 



11. A. biflorum (Brign.) R. & S. Tufted perennial; stem 1..5-6 dm. high, 

 often somewhat decumbent at the base; leaf-blades 5-15 cm. long, 2-6 mm. wide, 

 flat or somewhat involute; spike 2.5-10 cm. long, 4-6 mm. wide; spikelets 

 3-6-flowered; lemma 5-7-nerved, 8-12 mm. long, acuminate or short-awned. 

 A. violaccum (Hornem.) Lange. Mountains: Greenl. — N.Y. — Neb. — N.M. — 

 Alaska; Eurasia. Suhalp. — Alp. Jl-S. 



12. A. tenerum Vasey. Stem 3-10 dm. high; leaf -blades 2-6 mm. wide, 

 7-15 cm. long, scabrous, flat or involute; spike slender, 1-1.5 dm. long, lax; 

 spikelets 3-5-flowered; empty glumes 10-12 mm. long, acute to awn-pointed, .5- 

 nerved; lemma 8-10 mm. long, lanceolate; awn 1-4 mm. long or more. Rye 

 Grass. Dry soil: B.C. — Cahf. — N.M. — Minn. Plain — Submont. Je-Au. 



13. A. inerme (Scribn. & Smith) Rydb. Stems 8-10 dm. high, glabrous; 

 leaf-blades erect, 1-2 dm. long, 2-4 mm. wide, more or less pubescent above, 

 somewhat glaucous, flat or involute; spike 1-3 dm. long, lax; spikelets distant, 

 1.5-2 cm. long, 6-10-flowered; empty glumes 8-10 mm. long; lemma 10-12 mm. 

 long, smooth, often mucronate or with a short awn-tip. Closely related to A. 

 spicalum and A. Vaseyi. Plains and meadows: B.C. — Wash. — -Utah — Wyo. 

 Submont. Je-Au. 



14. A. albicans Scribn. & Smith. Stem erect, 3-6 dm. high, glaucous; leaf- 

 blades rigid, ascending, involute, scabrous, 7-20 cm. long, 2-3 mm. wide; spike 

 slightly nodding, 7-10 cm. long; spikelets 8-10, .5-7-flowered, 1.5-18 mm. long; 

 empty glumes pubescent, oblanceolate, acuminate, tipped with an awn 4-0 mm. 

 long; lemma about 9 mm. long, ovate-lanceolate; awn 12-15 mm. long. Hills 

 and benchlands. Mont. — -Wyo. — -w Neb. — S.D. Submont. Je-Au. 



15. A. Grifflthsil Scribn. Sz Smith. Stem glabrous, 3-8 dm. high, striate; 

 leaf-blades rather rigid, mostly involute, .5-12 cm. long; spike erect, 8-15 cm. 

 long; spikelets j)ale, closely 5-7-fiowered; empty glumes 8 nun. long, with awns 

 3 mm. long; lemma oblong, 8-10 mm. long; awns 8-10 mm. long. Plains: Wj-o. 

 — N.D.— S.D. Plain. Au. 



16. A. Palmeri (Scribn. (t Smith.) Rydb. Stem 3-6 dm. high; leaf-blades 

 glaucous, 1-2 dm. long, 3-4 mm. wide, at last involute, scabrous and often 

 sparingly ])ubescent on both sides; spikes rather dense, 1-1.5 dm. long; spikelets 

 compressed, 1..5-2 cm. long; lemma about 1 cm. long, acuminate, pilose to 

 hispidulous-scabrous. Bottom-lands and hillsides: N.M. — -Colo. — ^Utah — -Ariz. 

 Son. — Submont. My-Jl. 



17. A. pseudorepens Scribn. A Smith. Stem 3-10 dm. high, glabrous; 

 leaf-blades scabrous througliout, 12-20 cm. long, 2-6 mm. wide, flat, or involute 

 when dry; spike 1-2.5 dm. long; spikelets rather distant, 10-16 nun. long, 3-7- 



