72 GRAMINEAE (GRASS FAMILY) 



erect. 



15. Poa subpurpurea Rydb. Bull.Torr. Bot. Club 32: 606. 1905. A tufted, 

 _ct, somewhat wiry perennial: culms 2-4 dm. high: leaves flat: panicle ob- 

 long or pyramidal, dense, 4-6 cm. long: spikelets ovate, 3-5-flowered, 6-8 mm. 

 long: lemma oval, obtuse, minutely scabrous on the back and hispid-ciliate 

 on the keel; palet about 5 mm. long. (P. purpurascens Vasey, Bot. Gaz. 

 6: 297. 1881; the name preoccupied.) Alpine; Colorado (?) to British Co- 

 lumbia. 



16. Poa subaristata Scribn. Beal's N. Am. Gr. 2: 533. 1896. Slender, 

 densely tufted, 2-5 dm. high: leaves of sterile shoots conduplicate, scabrous, 

 6-12 cm. long; sheaths of the stem 2, smooth, the upper one nearly half as 

 long as the stem; the upper leaf pungent, 4-5 cm. long: panicle dense, some- 

 what interrupted, 4-7 cm. long: spikelets 4-7-flowered, 6-10-mm. long: glumes 

 subequal, linear-lanceolate, 5-6 mm. long, 1-nerved ; lemma as long, scabrous 

 on the nerves; palet shorter, ciliate on the keels. Colorado to Montana and 

 Idaho. 



17. Poa epilis Scribn. Circ. U. S. Dept. Agr. Div. Agrost. 9: 5. 1899. 

 Densely tufted, 5-10 dm. high: basal leaves numerous, slender, acute, flat (or 

 convolute when dry), those of the sterile shoots 1-2 dm. long; sheaths much 

 shorter than the internodes: panicle dense, bronzed or purple: spikelets some- 

 what compressed, about 5 mm. long: glumes smooth, unequal, acute, or 

 acuminate; the lower 1-nerved; the upper 3-nerved, 3 mm. long and exceeding 

 the lower; lemma 5-nerved, rough-hispid on the back, obtuse; palet ciliate on 

 the keels, with 2-toothed apex: grain acute at both ends, with a white tubercle 

 at the apex. Colorado to Wyoming and Montana. 



18. Poa longipedunculata Scribn. Bull. U. S. Dept. Agr. Div. Agrost. 

 11: 54. 1898. Slender, tufted, erect, 4-7 dm. high, with short creeping root- 

 stocks, smooth except on the axis of the panicle: leaf blades of the sterile 

 shoots 5-20 cm. long; those of the culm two or three, the uppermost some- 

 times reduced to a mucronate point: panicle dense, 5-7 cm. long; its branches 

 1-2 cm. long: spikelets somewhat compressed, 3-5-fl.owered, about 6 mm. 

 long: glumes scabrous on the keels, the first 2-nerved, the second 3-nerved, 

 with broadly subhyaline margins; lemma roughened on the keel above and 

 finely pubescent toward the base, about 4-nerved; palet shorter than its 

 lemma. Frequent throughout our range on mountain slopes. 



19. Poa Fendleriana (Steud.) Vasey, 111. N. Am. Gr. 2: 74. 1893. Pale 

 green, strict and nearly smooth, 2-5 dm. high, from short rootstocks: leaves 

 as in the last but less harsh and rigid: panicle spike-like, lanceolate or slightly 

 spreading, 5-10 cm. long: spikelets ovate-lanceolate, compressed, 4-8-flowered, 

 7-8 mm. long: glumes subequal, oval, acute, irregularly toothed or obtuse, 

 1-3-nerved, 4-5 mm. long; lemma about as long, pubescent below on the keel 

 and marginal nerves, otherwise smooth. P. californica; P. andina Nutt. 

 (P. brevipanicutota S. & W. Circ. U. S. Dept. Agr. Div. Agrost. 9: 2. 1899.) 

 New Mexico to Wyoming and westward. 



20. Poa longiligula S. & W. Circ. U. S. Dept. Agr. Div. Agrost. 9: 

 Is'.)'.). Glaucous, tufted, 3-5 dm. high: culms rather rigid and harsh: basal 

 leaves numerous, flat or conduplicate, 1-2 dm. long, with a conspicuous de- 

 current ligule; the cauline few and short: panicle dense, ovate, erect: spikelets 

 eompressrd, ovate-lanceolate, 4-6-flowered, 6-10 mm. long: glumes unequal, 

 rough-hispid on the back; the lower 1-nerved; the upper 3-nerved and about 

 5 mm. long; lemma 5-nerved, somewhat scabrous on the back and woolly- 

 pulieseent on the lower half of the back and the marginal nerves, usually 

 erofle-dentate, with broad hyaline margins; palet shorter than its glume, with 

 green hispid pubescent keels. Frequent in our range. 



21. Poa laevigata Scribn. Bull. U. S. Dept. Agr. Div. Agrost. 5: 31. 1897. 

 Culms densely tufted, (i S dm. tall, erect, slender, the innovations 1-2 dm. 

 long: sheaths smooth and glabrous; leaves 1 dm. or less long: panicle very 

 -lender, s 11 cm. long, its larger branches 3-5 cm. long: spikelets 5-7 mm. 

 long, :'. i-flourml, lemmas M-4 mm. long, hispidulous all over, obtuse to 

 aeuii-h. Very nearly related to the preceding; same range. 



22. Poa nevadensis Vasey, Scribn. Bull. Torr. Bot. Club 10: 66. 1883. 



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