150 FLORA. 



i. Sitanion elymoides Raf. (I. F. f. 540.) Culms 1.5-6 dm. tall; sheaths 

 sometimes hirsute; leaves 5-17.5 cm. long, 1-4 mm. wide, often stiff and erect, 

 usually rough, sometimes hirsute.-, flat or involute; spike 5-15 cm. in length; spike- 

 lets 1-5 -flowered; empty scales entire or divided, often to the base, the divisions 

 awl-shaped and bearing long unequal slender awns 2.5-8.5 cm. in length; flower- 

 ing scales 6-10 mm. long, 5 -nerved, scabrous, at least toward the apex, bearing a 

 long slender divergent awn 2.5-8.5 cm. in length, the apex of the scale sometimes 

 2-toothed. the teeth often produced into short awns. In dry soil, S. Dak. to Ore., 

 south to Kans., Tex., Ariz., and Cal. July-Aug. \Elymus Sitanion Schultes.] 



101. ^LYMUS L. (See Appendix.) 



Tall grasses, with usually flat leaves and dense terminal spikes. Spikelets 2- 

 several-flowered (rarely 1 -flowered) sessile, usually in pairs, occasionally in 3's or 

 more, in alternate notches of the continuous or jointed rachis, the empty scales 

 forming an apparent involucre to the cluster. Two lower scales empty, narrow, 

 acute, sometimes awned, entire ; flowering scales shorter, rounded on the 

 back, 5 -nerved, usually bearing an awn. Palet a little shorter than the scale, 2- 

 keeled. Stamens 3. Styles very short, distinct. Stigmas plumose. Grain 

 sparsely hairy at the summit, adherent to the palet. [Greek, to roll up, referring 

 to the involute palet.] About 40 species, natives of temperate regions. Besides 

 the following, some 15 others occur in the western parts of N. Am. 



Flowering scales conspicuously awned (rarely awnless in No. 2). 

 Spikelets divergent from the rachis of the broad spike. 



Empty scales narrowly awl-shaped ; spike slender. 1. E. striatus. 



Empty scales linear-lanceolate to linear ; spike stout. 



Flowering scales glabrous. 2. E. Virginicus. 



Flowering scales more or less appressed-pubescent, usually densely so. 



Empty scales linear, thick, firm, bearing generally a much shorter awn, 



3. E. hirsutiglumis. 

 Empty scales narrowly lanceolate, rather thin, bearing commonly an 

 awn equalling or exceeding themselves. 

 Spike rather loosely flowered, nodding at the summit, usually long- 



exserted. 4. E. Canadensis. 



Spike densely flowered, compact, strict, usually included at the 

 base. 5. E'. robustus. 



Spikelets appressed to the rachis of the narrow spike. 



Empty scales narrowly lanceolate, acuminate or awn-pointed. 



6. E. glaucus. 

 Empty scales awl-shaped, bearing an awn equalling or exceeding themselves. 



7. E. Macounii. 

 Flowering scales awnless or awn-pointed. 



Flowering scales glabrous. 8. E. condensatus. 



Flowering scales villous. 9. E. arenarius. 



i. Elymus striatus Willd. Slender Wild Rye. (I. F. f. 533.) Culms 

 3-9 dm. tall; sheaths glabrous or hirsute; leaves 1.25-2.25 dm. long, 4-10 mm. 

 wide, smooth or slightly rough beneath, pubescent above ; spike 6-12 cm. in length, 

 often nodding, broad, slender, dense; spikelets divergent from the rachis, 1-3- 

 flowered; empty scales awl-shaped, 1.8-2.4 cm. long, including the slender rough 

 awn, 1-3-nerved, the nerves, and often the whole scale, rough, hispid or hirsute ; 

 flowering scales about 6 mm. long, smooth, scabrous or hispid, bearing a slender 

 rough awn 1.6-3 cm * ^ n length. In woods and on banks, Me. and Ont. to Tenn., 

 Neb. and Kans. June-July. 



2. Elymus Virginicus L. Terrell-grass. Virginia Wild Rye. (I. F. f. 

 534.) Culms 6-9 dm. tall; sheaths sometimes pubescent, the uppermost often in- 

 flated and enclosing the peduncle and the base of the spike ; leaves 1.25-3.5 dm. 

 long, 4-16 mm. wide, rough; spike 5— 17.5 cm. in length, broad, stout, upright ; 

 spikelets divergent from the rachis, 2-3-flowered ; empty scales thick and rigid, 

 lanceolate, 1.6-2.4 cm. long, including the short awn, 5-7-nervcd; flovverino scales 

 6-8 mm. long, glabrous, bearing a rough awn 4-18 mm. in length, or rarely awn- 

 less. In moist soil, especially rlong streams, N. S. and N. B. to Manitoba, south 

 to Fla. and Tex. Ascends to 600 m. in N. Car. July-Aug. 



