580 POACE.E. 



mm. wide, apex abruptly pointed, those of the cnlm 2 in number, 

 0.5-5 cm. long. Panicle erect, rarely spreading, 5-15 cm. long, 

 rays in twos or threes. Spikelets rather firm, 5-8 mm. long, 2-5- 

 (mostly 3-) flowered, pubescent, elliptical-lanceolate, joint of 

 rachilla 1-1.5 mm. long; empty glumes obtusely keeled, 3-nerved 

 near the base, first linear-lanceolate, about 3 mm. long, second el- 

 liptical-lanceolate, about 4 mm. long; floral glume 3.5—4.5 mm. 

 long, elliptical or linear-oblong, acute or obtuse, entire or erose, 

 bluntly keeled or almost round on the back, pubescent on the lower 

 third, puberulent above; palea linear, 2-toothed, 3.5 mm. long, mi- 

 nutely scabrous on tlie back and keels. 



Dr. Yasey, after prolonged study of large numbers of specimens, 

 found them very variable and perplexing, and says in Coult. Bot. 

 Gaz. 6:297 (1881): "It may well be conjectured that Nature is 

 now engaged in the work of differentiation, and that iu process of 

 time the lines will become more sharply defined, and several new 

 species established." 



Montana, Scrihner 396, and for U. S. Dept. Agricul. 670, 

 Tiveedy 632, 637 ; Oregon, Howell. 

 Eocky Mountains to California. 

 Var. stenophyla Vasey, ined. 



Panicle slender, open, first glume 4 mm. long, second 5 mm. 

 long; floral glume 5 mm. long; the latter 

 minvitely scabrid below or smooth; palea 4.7 

 mm. long. 



Oregon, Howell in 1887. 

 Montana, Oregon, and California. 

 15. A. Canbyi (Scribn.). Glyceria Canbyi 

 Scribn. Bull. Torr. Club, 10:77, t. (1883). 



An erect smooth stout perennial, 60-90 

 cm. high, culms simple. Sheaths shorter 

 Fig. 115.— Atropis Can- than the interuodes; ligule broad, obtuse, 4-6 



byi Spikelets. (Scrib- ^^^^ ^ blades of the culm 3-4 in num- 



ner.) =" ' 



ber, flat below, conduplicate above, scabrous, 



the upper about 15 cm. long, 4-6 cm. wide. Panicle exserted, 



linear or lanceolate, usually interrupted below, about 15 cm. long. 



