GRAMINEAE (GRASS FAMILY) 71 



8. Poa reflexa Vasey and Soribn. Contrib. U. S. Nat. Herb. 1: 276. 1893. 

 Culms 2-4 dm. high, slender, erect, smooth: leaves of the culm about 3, mostly 

 narrow, acute, 6-8 cm. long: sheaths long, smooth; ligule obtuse, about 2 mm. 

 lon^: panicle pyramidal, &-10 cm. lo&g, with about 6 nodes; the branches 

 capillary, rather distant, the lower ones 5-8 cm. long, smooth, spreading and 

 becoming reflexed, spikelet-bearing near the end: spikelets 2-3-flowered, 

 3-4 mm. long: glumes acute, smooth; lenmia ovate-lanceolate, acute, ob- 

 scurely nerved, pubescent on the nerves and at the base; palet pubescent on 

 the keels. (P. acuminata Scribn. Beal's N. Am. Gr. 2: 538. 1896; P. pudica 

 Rydb. Bull. Torr. Hot. Club 32: 603. 1905.)— Wet sandy soils, at middle or 

 higher elevations; Montana to New Mexico. 



9. Poa laxa Haenke, Sudet. 118. 1791. Culms 3 dm. tall or less, erect, sim- 

 ple; leaves 2.5-7.5 cm. in length, the branches usually erect, sometimes 

 ascending, 2.5 cm." long or less: spikelets 3-5-flowered, 4-5 mm. long; glumes 

 usually 3-nerved, acute, glabrous, rough on the keel at its apex; lemma 

 3-3.5 mm. long, obtuse, 3-nerved, or sometimes with an additional pair of 

 obscure nerves, the mid-nerve pilose on the lower half, rough above, the lateral 

 ones pilose for one third their length. — -In the Rocky Mountains and in those 

 of New England and New York; infrequent in our range. 



10. Poa alpina L. Sp. PI. 67. 1753. Smooth and glabrous: culms 1-4.5 dm. 

 tall: Ugule 2 mm. long, truncate; leaves 2.5-7.5 cm. long, 2-4 mm. wide, 

 abruptly acute: panicle 2.5-7.5 cm. in length, the branches generally widely 

 spreading, 2.5 cm. long or less: spikelets 3-5-flowered, 5-6 mm. long: glumes 

 broad, glabrous, rough on the keel, acute; lemma about 4 mm. long, obtuse, 

 pilose for half the length, pubescent between the nerves toward the base. — 

 Frequent in the mountains and extending northward and eastward. 



11. Poa Pattersonii Vasey, 1. c. 275. Culms low, densely tufted, 15-25 cm. 

 high, slender, naked above: radical leaves numerous, 5-8 cm. long, very nar- 

 row, flat or conduplicate, smooth: panicle dense, weakly erect, or nodding; 

 branches mostly in twos, subappressed: spikelets 4-6 mm. long, 2-3-flowered: 

 glumes nearly as long as the lemma, acute; lenmia purplish, acute, 4 mm. 

 long, pubescent on the lateral nerves and below the middle but not webbed 

 at the base; palet pubescent on the keels. (P. rupestris Vasey, a name re- 

 placed by P. rupicola Nash, Mem. N. Y. Bot. Gard. 1: 49. 1900.) — Alpine; 

 Colorado and Wyoming. 



12. Poa Lettermannii Vasey, Contrib. Nat. Herb. 1: 273. 1893. Dwarf, 

 densely tufted, 5-10 cm. high: leaves mostly radical, flat, 3-5 cm. long; ligule 

 rather conspicuous, acute; cauUne leaves 1 or 2: panicle 10-25 mm. long, rather 

 dense; branches mostly in twos, short, erect, with 1-3 spikelets: glumes nearly 

 as long as the spikelets, acute, nearly smooth, 3-4 mm. long; lemma shorter, 

 ovate-oblong, acute, obscurely nerved, smooth; palet 2-toothed at the acumi- 

 nate apex. — Alpine summits, Colorado to Washington. 



13. Poa Wheeleri Vasey, Rothr. Rep. 6: 291. 1878. Culms 3-8 dm. high, 

 from running rootstocks: Ugules about 2 mm. long; leaves of sterile shoots 

 15-24 cm. long, 2-4 mm. wide, rigid, conduplicate or involute, with a firm 

 obUque point: panicle open, 10-15 cm. long, its slender branches mostly in 

 pairs, the longer about 5 cm. long: spikelets lance-elliptic, 4-6 mm. long, 

 3-flowered: glumes subequal, 3-nerved; lemma oval, subacute, about as long, 

 ciUate on the lateral nerves and below; palet truncate, ciliate on the keel. — 

 Frequent in our range and extending to Washington. 



14. Poa nervosa (Hook.) Vasey, 111. N. Am. Gr. 2: 81. 1893. ' Culms 4-8 

 dm. high, rather slender, smooth: radical leaves narrowly linear, 15-25 cm. 

 long; those of the culms about 3, rather distant, erect, flat, 3-8 cm. long, 

 2-4 mm. wide: panicle 5-12 cm. long, branches spreading, the lower 2-5 

 together, fiUform, naked below, few-flowered near the ends: spikelets 3-8- 



. flowered, 4-5 mm. long: lemma linear-lanceolate, strongly 5-nerved, minutely 

 scabrous on the nerves; palet and lemma subequal. [P. Traceyi Vasey, 

 Contrib. U. S. Nat. Herb. 1: 276. 1893; P. flexuosa occidentalis Vasey; P. 

 occidentalis (Vasey) Rydb.; P. caUichroa Rydb. Bull. Torr. Bot. Club 32: 603. 

 1905.] — Idaho and Montana to Colorado. 



