230 POACE^. 



A slender erect tufted grass, 20-40 cm. high. Sheaths of the- 

 culm extending well up the culm; ligule 1.5-3 mm, long; blades of 

 the sterile shoots involute, filiform, somewhat flexuose, 15-25- 

 cm. long, those of the culm 5-8 cm, long. Panicle simple, thin, 

 linear, 8-12 cm. long, the lower rays in pairs, the longest 2,5-3 cm. 

 long, bearing 1-2 spikelets. Empty glumes membranous-char- 

 taceous, purple at the base, linear, 1-nerved, first 3-3.5 mm. long, 

 second 4 mm. long; floral glume sparsely clothed with short hairs 

 on the lower half, ovate when spread, 3.3 mm. long, including the 

 short obtuse callus and the 2-toothed apex; awn scabrous, irregu- 

 larly bent and slightly twisted, 10-15 mm. long; palea oval, 2.5- 

 mm. long. Grain elliptical, compressed, 2 mm. long. 



California, Bolander 6097. 



California and Nevada. 



11. 0. micrantha (Trin. et Eupr.). Thurb. Proc. Acad. Phila. 

 1863, 78 (1863). 0. micrantha Thnvh. Porter and Coult. Syn. FL 

 Colo. 145 (1874). Urachne micrantha Trin. & Rupr. Mem. Acad. 

 St. Petersb. (VI.) 5:16(1842). 



Culms slender, 60 cm. high. Sheaths shorter than the inter- 

 nodes; ligule membranous, not ciliate, 1 mm. long; blades scabrid, 

 involute, or flat, 10-30 cm. long, 2-2.5 mm. wide, in some cases 

 reaching as high as the panicle, in others much shorter. Panicle 

 exserted, thin, diffuse, 8-16 cm. long, rays mostly in pairs. Spike- 

 lets ovate-lanceolate, 2.5-3 mm. long; awn deciduous, 5-10 mm. 

 long; empty glumes ovate-acute, hyaline, chartaceous, shining, sub- 

 equal, 1-2-nerved near the base on either side of the mid nerve; 

 floret smooth, elliptical, 2 mm. long. 



Montana, Anderson, Williams; Colorado, Letterman 31 ; Utah,, 

 Jones ; Arizona, Vasey for U. S. Dept. Agricul. 296, Jones 4034, 



Colorado to Arizona and Montana. 



12. 0. erecta (Scribn.) Beal, Coult. Bot. Gaz. 15 : 112 (1890). 

 Bliim Pringlei Scribn., Vasey, Contrib. U. S. Nat, Herb. 3:54 

 (1892). 



Culms erect, rather slender, 60-120 cm. liigh. Sheaths longer 

 than the intei'iiodes; ligule 2-3 mm. long; blades of the sterile 

 shoots numerous, half or two-thirds as long as the culm, scabrous. 



