228 POACExE. 



toothed, delicately o-nerved near tlie base, greenish white; floral 

 glume clothed with short hairs and very short tufts near the base. 



" It has much the habit and appearance of 0. Canadensis 

 Torr., but differs essentially in its simple and contracted panicle, 

 its shorter outer glumes, and its longer and somewhat persistent 

 awn." Scribn. Coult. Bot. Gaz. 11: 169 (1886). 



Montana, Williams; Wyoming, Bnffum c 2, c 71. Oregon, 

 Cusick for U. S. Dept. Agricul. 294. 



Oregon to Montana. 



7. 0. juncea (Michx.) B. S. P. Prel. Cat. N. Y. 67 (1888). 

 Stipa juncea Michx. Fl. Bor. Am. 1 : 51 (1803). SiijKi Canadensis 

 Poir. Lam. Encyl. 7: 452 (1806). JJilium jmngens Torr. Fl. U. S. 

 1:78 (1824). 0. Canadensis Torr. Fl. N. Y. 2:433 (1843). 



Culms slender, 20-40 cm. high. Sheaths rough; ligule not 

 ciliate. 3-4 cm. long; blades scabrid, those of the culm very short 

 or sometimes long, those below tapering into a petiole, firm, invo- 

 lute, 15-20 cm. long, 2 mm. wide, when spread. Panicle exserted, 

 simple, narrow or diffuse, 4-8 cm. loiig. Si)ikelets elliptical, acute, 

 about 4 mm. long, awn short and deciduous or wanting, empty 

 glumes subequal, first oval, truncate, membranous with 5 incon- 

 spicuous nerves below, second a little narrower; floret whitish, 

 pubescent, with a very short thin tuft at the base. 



Vermont, U. S. Dept. Agricul. 292, from Pr ingle; Massachu- 

 setts, Cooley ; Rhode Island, Clarh 3207; Michigan (Keweenaw), 

 Wood, Wlieeler ; Minnesota, State Survey 38. 



Northern States to Colorado, May. 



8. 0. Hendersoni Vasey, Contrib. TJ. S. Nat. Herb. 1:267 

 (1893). 



A densely tufted grass, 15-20 cm. high. Lower sheaths rather 

 loose; blades scabrous, condii plicate, rigid, pungent, 8-10 cm. long. 

 Panicle narrow, 5-8 cm. long, rays mostly in twos, the longest 3-5 

 cm. long, bearing 2-4 spikelets near the apex. Spikelets 4 mm. 

 long, empty glumes broadly oblong, obtuse and toothed, first 3- 

 nerved, second 5-nerved; floral glume linear-oblong, 3.5 mm. long, 

 smooth, coriaceous, obscurely 5-nerved, bearing 2 lateral teeth, awn 

 curved, caducous, 10-12 mm. long. 



