No. 48. 

 TRISETUM CERNUUM Trin. Mem. Acad. St.-Peters. 1830. i. 61. 



Plant perennial, loosely tufted, somewhat thickened at base. 



Culms erect, smooth, 2 to 3 feet high. 



Leaves of culm usually three; sheaths rather loose, open above, striate, smooth or 

 scabrid above or even cauescent, shorter than the internodes ; blades flat, scabrid on 

 both sides or nearly smooth beneath, 5 to 10 inches long, 3 to 6 lines wide; ligule ovate, 

 lacerate, 1 to 6 lines long. 



Inflorescence a, rather loose, open, flexuose or nodding panicle 5 to 8 inches long ; 

 rays in twos, threes, or fours at the 7 to 10 nodes of the scabrid common axis, slender, 

 flexuose, spreading, scabrid, bearing beyond the middle spikelets on pedicels 1 to 5 

 lines long. 



Spikelets compressed, 2-, 3-, or rarely 4-flowered, 3 to 4 lines iong ; first empty glume 

 narrowly ovate, acute, carinate, thin, minutely hispid on the keel, 1 -nerved, 1 to 1£ 

 lines long; second empty glume broadly oblong, obtuse or acuminate, thin, hispid on 

 the keel above, 3-nerved below, 2 to 2£ lines long; awn arising below the base of the 

 cleft, 3 to 5 lines long; hairs of the callus short; internode of the rachilla villose, 1 

 line long, upper one bearing a slender awn about one line long; palet oblong, erose at 

 the obtuse apex, slightly arched, thin, minutely scabrid, hispidulous on the two keels, 

 li lines long; grain narrowly oblong, light yellow, opaque, 1£ lines long. 



Pla.te XLVIII; a, spikelet enlarged G times; 6, empty glumes; c, floral glume, 

 side view ; d, palet, dorsal view ; e, palet and internode of rachilla, side view. 



Northern California to Alaska. 



