548 POACE^. 



cm. long, rays smooth, in pairs, the longest 1.5-3 cm. long, densely 

 flower-bearing above the middle. Spikelets oval, 4-6 mm. long, 

 3-5-flowered, softly scabrid; empty glumes lance-ovate, acute, 3- 

 nerved, second 3.5-4.2 mm. long, reaching three-fourths to four- 

 fifths over the glume above ; floral glume with a few webby hairs at 

 the base, 3-3.7 mm. long, involute, broadly ovate, abruptly acute; 

 palea linear-lanceolate, ciliate on the keels. 



Oregon, Hoiuell in July 1882, and in 1887. 



Some of these have been distributed as P. abhreviata E. Br., 

 but Dr. Yasey had an opportunity for comparison and I follow him 

 in the selection of name. 



Oregon to the Arctic Coast. 



30. P. Grayana Vasey, Contrib. U. S. Nat. Herb. 1:272 

 (1892). 



Eootstocks and sterile shoots numerous; culms 30-50 cm. high. 

 Blades of sterile shoots conduplicate, abruptly jiointed, 15-20 cm. 

 long, 2 mm. wide ; leaves of tlie culm 2 in number; ligule decurrent, 

 2-4 mm. long; upper blade 4-6 cm. long. Panicle open, 8-12 cm. 

 long, rays in pairs, the longest 4-6 cm. long, bearing 3-6 sjukelets 

 on the outer third. Spikelets tinged with purple, the margins of 

 the glumes brown, 6-8 mm. long, 3-5-flowered; empty glumes oval, 

 subacute, 3-nerved, first about 3.5 mm. long, second 4-4.5 mm. 

 long; floral glume pubescent on the keel and marginal nerves of the 

 lower two-fifths, 3.5-7 mm. long, ovate, obtuse, erose; palea but 

 little shorter than its glume, linear when closed, ciliate on the keels. 



Colorado, Patterson 14 in 1885. 



High Mountains about Gray's Peak; altitude 10,000-12,000 feet. 



In herb. U. S. Dept. Agricul. 



31. P. Thurberiana (Kuntze) Vasey(?) 



An erect light-green rather slender perennial, 50-80 cm. high, 

 culms and leaves smooth or scabrid. Sterile shoots few, the blades 

 20-40 cm. long, leaves of the culm 4-5, sheaths mostly longer than 

 the internodes, smooth; ligule truncate, lacerate, 4 mm. long; 

 blades mostly flat, acuminate, 2 mm. wide, the ujiper extending to 

 the base of the panicle or beyond. Panicle narrow, thin, 15-25 

 cm. long, rays in threes and fours, some of them very short, the 



