No. 52. ■ 



ARCTAGROSTIS LATIFOLIA (E. Br.) Griseb. in Ledeb. Fl. Eoss. iv. 434 



(1853)5 Colpodium latifolium E. Br. Chlor. Melv. 286 (1823). 



Plant perennial, with strong, creeping rootstock, usually purple in the inflores- 

 cence. 



Culms erect or slightly decumbent at the base, robust, smooth, leafy nearly to tlie 

 panicle, 6 to 12 inches tall. 



Leaves of the culm usually 3 ; sheaths loose, open above, smooth, usually exceed- 

 ing the internodes; blades flat, striate, scabrous above, 2 to 4 lines wide, 2 to 4 inches 

 long; ligule usually lacerate at the obtuse apex, 2 lines long. 



Inflorescence a rather closely flowered, contracted panicle, 2 to 5 inches long; rays 

 in semiverti dilate clusters of 3 to 5 at each of the 6 to 8 nodes, appressed or slightly 

 spreading, unequal, an inch long or less, spikelet-bearing to the base, or the longer 

 ones sometimes naked below. 



SpiJcelets 2 to 2£ lines long, 1-flowered, with a slender capillary rudiment; empty 

 glumes broadly lance-oblong, acute or subacute, thin, smooth, the first 1-nerved, 1 to 

 1£ lines long, the second J line longer and 3-nerved; floral glume broadly lance-oblong, 

 subacute or often mucronulate, minutely roughened throughout, slightly pubescent on 

 the keel below, obscurely 5-nervecl, 2 lines long; palet broad and glumaceous in form 

 and texture, margins not infolded, purple like the glume and about equaling it in 

 length, pubescent on the 2 nerves; stamens 3, with short filaments and yellow anther 

 1 line long. 



Plate LII; a, spikelet with floret and rudiment lifted out and opened to show 

 the stamens; b, first empty glume; c, second empty glume; d 7 floral glume; e, palet. 



Alaska to Greenland. This species resembles Dupontia Fisheri more nearly 

 than any other of the same region, but that is readily distinguished by its long, golden, 

 empty glumes. 



