88 . POACEAE 



25. F. reflexa Buckley. Simple or rarely tufted; stem •erect, 2-5 dm. high; 

 leaf-blades f^.at or looseh' involute, 2-10 cm. long; panicle 5-12 cm. long; spike- 

 let.s 1-3- (rarely 4- or 5-) flowered, 5-7 mm. long; lemma lanceolate, smooth or 

 scabrous, 4.5-6 mm. long, attenuate; awii scabrous, 2-12, usually 5-8 mm. long. 

 Dry places: B.C. — Utah — Calif. Son.- — Suhtnont. My-Je. 



26. F. megalura Xutt. Simple or somewhat tufted; stems 2-6 dm. high, 

 glabrous; leaf-blades involute or flat; panicle 1-3 cm. long; spikelets 4-5-flowered, 

 8-11 mm. long; lemma obscurely 5-nerved, 4-6 mm. long, scabrous and cihate 

 on its upper half; awn scabrous, 8-15 mm. long. Dry soil: B.C. — -Ida. — Ariz. 

 — Cahf.; Mex., Equador, Peru, and Chili. Subuwnt. Ajj-Je. 



69. HESPEROCHLOA (Piper) Rydb. 



Dioecious perennials, densely tufted, producing both intravaginal innova- 

 tions and stout extravaginal stolons. Panicle narrow. Spikelets 3-5-flowered, 

 those of the staminate plant flattened, those of the pistillate one turgid. Empty 

 glmnes 2, lanceolate, subscarious, the lower 1-nerved, the upper 3-nerved. 

 Lemma ovate, 5-nerved, acuminate. Palet shorter than the lemma. Ovary 

 hispidulous at the apex, deeply sulcate; stigma elongate, the numerous short 

 branches arising on all sides. Grain 2-dentate at the apex. 



1. H. Kingii (S. Wats.) Rydb. Stems stout, striate, glabrous, 4-10 dm. 

 high; leaf -blades firm, flat or loosely involute, coarsely striate, 1-3 cm. long, 3-6 

 mm. wide; panicle narrow, erect, 8-20 cm. long; spikelets (i-lO mm. long; empty 

 glumes nearly smooth, shining, the first 3-4.5 mm. long, the second 5-7 mm. 

 long; lemma ovate, abruptly acuminate, scabrous, 5-8 mm. long. Poa Kingii 

 S.Wats. Fesluca confiiiisYasey. Canons and hillsides: Ore. — Calif. — Colo. — 

 Neb. — Mont. Submont. — Subalp. Je-Au. 



70. BROMUS L. Brome-grass, Ches.^ Cheat. 



Annuals or perennials, with paniculate inflorescence. Spikelets usually large, 

 often drooping, several-many-flowered; flowers perfect or the upper ones im- 

 perfect. Empty glumes 2, membranous, persistent, narrow, unequal, acute or 

 the second one sometimes short-awned. I.,emma longer than the glumes, 

 rounded or keeled on the back, u.sually awned, the awn dorsal antl inserted just 

 below the 2-toothed apex. Palet shorter than the lemma, 2-keeIed. Ovary 

 crowned with a villous appendage, at the base of which arise the lateral styles; 

 stigmas plumose. 



Second empty glume 5-7-nerved; first empty glume 3-nerved. 

 Lemma compressed-keeled. 



Palet less than three-fourths as long as the lemma, which Is scarcely toothed. 

 Sheaths and usually also the blades hairy; lemma pubescent or hispidulous- 

 scabrous. 

 Lemma hispidulous-scabrous. 



Awns 10-1.5 mm. long. 1. B. Hookerianus. 



Awn 4-6 mm. long. 2. B. Flodmanii. 



Lemma pube-scent; awns 4-8 mm. long. 



Lower branches of the panicle 7 cm. long or less, in fruit erect. 



Leaves flat, not canescent. 3. B. brcviaristatus. 



Leaves involute, canescent. 4. B. subvclutinus. 



Lower branches of the panicle 1 dm. long or longer, spreading in fruit. 



5. B. lalior. 

 Sheaths and blades glabrous or minutely scabrous. 



Panicle narrow, strict; awn 4-6 mm. long. 6. B. polyanthus. 



Panicle open, spreading and nodding; awn 6-7 mm. long. 



'). B. paniculatus. 

 Palet more than three-fourths as long as the lemma, which is distinctly toothed 

 at the ape.x. 8. B. unialoidrs. 



Lemma rounded on the back, broadly elliptic; introduced tufted annuals or biennials. 

 I^emma nearly as broad as long, awnless or with a very short awn. 



9. B. brizacformis. 

 Lemma much longer than broad, conspicuously awned. 

 Lemma ancl glumes glabrous. 



Awn nuuii shorter than the lemma, nearly erect. 



.^lieaths glabrous. 10. B. secalinus. 



Sheath- densely pubescent. 11. B. raccrnosus. 



Awn fullv as long as the lemma, at maturity strongly divergent; sheaths 

 pubescent. 12. B. patulus. 



