MANUAL OF THE GRASSES OF THE UNITED STATES 



259 



kota and Wyoming, south to South 

 Carolina, Alabama, and Texas. E. 

 arkansXnus Scribn. and Ball (E. 

 villosus forma arkansanus Fernald), 

 a relatively rare form with usually 

 slightly stouter culms, the spikes 

 mostly less drooping, scabrous glumes, 

 and glabrous to scabrous lemmas, is 

 found sparingly in Illinois, North 



Figuee 351. — Elymus villosus, X 1. (Commons 163, 

 Del.) 



Figure 352. — Elymus interruptus, X 1. (Grant 3071, 

 Minn.) 



Dakota, South Dakota, Nebraska, 

 Missouri, Maryland, Virginia, North 

 Carolina, Kentucky, Tennessee, Ar- 

 kansas, Texas, and Wyoming. Large 

 specimens resemble E. riparius, but 

 the palea reaches the base of the awn. 

 21. Elymus interruptus Buckl. 

 (Fig. 352.) Culms erect, 70 to 130 

 cm. tall; sheaths glabrous; blades 

 flat scabrous, 5 to 12 mm. wide; 

 spike flexuous or nodding, 8 to 20 

 cm. long; glumes setaceous or nearly 

 so, 1 to 3 cm. long, one or both 

 reduced in occasional spikelets, most- 

 ly flexuous or spreading, the nerves 

 obscure at least toward the base; 

 lemmas hirsute to scabrous, or gla- 

 brous, about 1 cm. long, about 2 mm. 

 across the back, the awn flexuous 

 or divergent, 1 to 3 cm. long. % 

 (E. diver siglumis Scribn. and Ball.) — 



