POACEAE. 31 



4. Agrostis hiemalis (Walt.) B. S. P. (A. scabra Willd.) On prairies and 

 hills, both in dry and wet soil, from Lab. to Alaska, Fla. and Calif.; also 

 in Mex. Alt. 4000-11,000 ft. Vicinity of Fort Collins; Baxter's ranch; 

 Poudre Canon; Twin Lakes; Taylor River; about Ouray; Gunnison; North 

 Cheyenne Canon; Ruxton Dell; Pagosa Springs; near Pagosa Peak; near 

 Boulder; mountains between Sunshine and Ward; Cameron Pass; Estes 

 Park; Grand Lake; Hamor's Lake; Grizzly Creek; Georgetown; mountains, 

 Larimer Co.; Marshall Pass; Valley and Empire; Veta Pass; Salida; Twin 

 Lakes; South Park; Como; gulch west of Soldier Canon; Little Beaver 

 Creek; between Graymont and Silver Plume; Steamboat Springs; Rabbit- 

 Ear Range. 



5. Agrostis tenuiculmis Nash. (A. tennis Vasey) In mountain meadows 

 from Mont, to Wash., Colo, and Calif. Alt. 10,000-11,500 ft. South Park; 

 Mt. Elbert; Dead Lake; near Pagosa Peak; summit of North Park Range, 

 Routt Co. 



6. Agrostis canina L. Along mountain brooks from Newf. and Alaska 

 to Pa., Colo, and Nev. Alt. about 9000 ft. Silver Plume. 



30. CALAMAGROSTIS Adans. REED-GRASS, BLUE-JOINT. 



Awn strongly geniculate, exserted, longer than the empty glumes ; callus-hairs 

 much shorter than the flowering glume ; panicle dense and spike-like. 



1. C, purpurascens. 



Awn straight or nearly so, included ; callus-hairs not much shorter than the flower- 

 ing glume (except in C. scopulorum). 



Panicle open, the lower branches wide-spreading and often drooping; leaf- 

 blades flat ; callus-hairs copious, almost equalling the glume. 

 Spikelets 4-6 mm. long ; empty glumes narrow, sharply acuminate ; awn stout, 

 attached below the middle, considerably exceeding the glume. 



2. C. Langsdorffii. 

 Spikelets 3-4 mm. long, awn attached near the middle, equalling or slightly 



exceeding the glume. 3. C. canadensis. 



Panicle more or less contracted, branches ascending. 

 Leaf-blades flat or nearly so. 



Callus-hairs copious, */$ as long as the flowering glume or longer. 

 Plant cespitose ; empty glumes acute. 9. C. hyperborea elongata. 



Plant not cespitose ; empty glumes long-acuminate. 



4. C. Scribneri. 



Callus-hairs sparse, l / 2 as long as the glume. 5. C. scopulorum. 

 Leaf-blades involute. 



Culm and the narrow leaf-blades soft, not rigid ; plant not cespitose. 

 Spikelets 2.5-4 mm - long ; empty glumes thin, sharp-acuminate. 



6. C. neglecta. 

 Spikelets 2 mm. long; empty glumes thickish, barely acutish. 



7. C. micrantha. 

 Culm and the usually broader leaf-blades hard, more or less rigid. 



Plant not cespitose, tall; panicle very long. 8. C. inexpansa. 

 Plant strongly cespitose ; panicle short and dense. 



9. C. hyperborea. 



i. Calamagrostis purpurascens R. Br. (Deyeuxia sylvatica Vasey; not 

 DC.) On dry, stony hills and alpine table-lands from Greenl. to Alaska, 

 Colo, and Calif. Alt 6500-12,500 ft. Silver Plume; mountains above Idaho 

 Springs; mountains between Sunshine and Ward; South Park; Mt. Ouray; 

 Mt. Garfield; Georgetown; Front Range, Larimer Co.; Webster; Pike's Peak; 



