38 POACEAE. 



50. TRIDENS R. & S. 



Second empty glume i-nerved. i. T. muticus. 



Second empty glume 3-5-nerved. 2. T. elongatus. 



1. Tridens muticus (Torr.) Nash. {Triodia mutica Benth.) On dry hills 

 from Tex. to Colo, and Ariz.; also northern Mex. — Caiion City {Porter). 



2. Tridens elongatus (Buckley) Nash. On plains and prairies from Tex. 

 to Colo, and Ariz. — Alt. about 5500 ft. — Pueblo; Canon City. 



51. DIPLACHNE Beauv. 



i. Diplachne acuminata Nash. In wet places from Ark. to Neb. and Colo. 

 — Alt. 4000-5500 ft. — New Windsor, Weld Co. ; Caiion City. 



52. BEDFIELDIA Vasey. 



I. Eedfieldia flexuosa (Thurb.) Vasey. (Graphephorum ilexuosum Thurb.) 

 In sand-hills from S. D. to Ind. Terr, and Tex. — Alt. 4000-5500 ft. — Sterling, 

 Logan Co. ; Fort Garland. 



53. KOELERIA Pers. Prairie-grass, June-grass. 



1. Koeleria cristata (L.) Pers. On prairies and plains from Ont. to B. C, 

 Pa. and Calif. A very variable species and perhaps a composite one. The 

 form common in the Rocky Mountain region has narrow, involute, glabrous 

 or puberulent leaves and narrow panicle, and has been described under the 

 name K. nitida Nutt. — Alt. 4000-10,000 ft. — Middle Park; Pagosa Springs; 

 vicinity of Boulder ; foot-hills, Larimer Co. ; Arboles ; Gunnison ; Sangre de 

 Cristo Creek; Golden; Twin Lakes; Mancos; Crystal Park; Minnehaha; 

 Cimarron; vicinity of Ouray; near Pike's Peak; Stove Prairie Hill, Larimer 

 Co. ; La Veta ; Manitou ; North Park ; Happy Hollow ; Hotchkiss ; Horse- 

 tooth Gulch; Table Rock; Manitou Junction; Dixon Canon; hills about 

 Dolores; dry hills along Trail Creek; Como; Grizzly Creek; Fort Collins; 

 Hardin's ranch ; Willow Creek, Routt Co. 



54. ERAGROSTIS Beauv. Skunk-grass, Stink-grass. 



Culm often decumbent at the base, much branched, 1-5 dm. high ; annuals ; 

 panicle green. 

 Spikelets 1.5 mm. or less wide; palet remaining attached to the continuous 



rachis, after the flowering glume has fallen. ji. E. Purshii. 



Spikelets 2.5-5 m™- wide ; palet falling with the flowering glume and the inter- 

 nodes of the rachis. 2. E. major. 

 Culm erect, rigid, simple ; perennial ; panicle purple. 3. E. pectinacea. 



1. Eragrostis Purshii Schrad. In dry or sandy places from Ont. to Wash., 

 Fla. and Calif. — Alt. 4000-7500 ft. — Alamosa, Conejos Co.; Caiion City, Fre- 

 mont Co.; along the river, Ft. Collins. 



i!. Eragrostis major Host. (£. poaeoides megastachya A. Gray.) Natural- 

 ized from Europe, in waste places and fields from Ont. to Wash., Fla. and 

 Calif.— Alt. 4000-6000 ft. — Vicinity of Boulder; Longmont; New Windsor, 

 Weld Co.; Caiion City, Fremont Co.; Cheyenne Mountain; Tobe Miller's 

 ranch; near Ft. Collins. 



