118 ^rrr-^ Bulletin VII. 1. 



2. First glume 3- to 5-nerved, the second 5- to 7-nerved; flow- 

 ering glumes broad and rounded on the back; spikelets 

 ovate or lanceolate 3 



2. First glume i-, the second 3-nerved; flowering glumes nar- 



row and somewhat keeled on the back, at least above . . 5 



3. Panicle erect, closely contracted, at least in part; whole plant, 



including the spikelets, softly pubescent . 4. B. mollis. 



3. Panicle usually nodding and more open; spikelets glabrous. 4 



4. Flowering glumes and paleas about equal in length; awns 



shorter than the glumes, usually a little flexuose, some- 

 times nearly wanting, sheaths glabrous . 3. B. secaltnus. 



4. Flowering glumes decidedly longer than the paleas; awns 



straight, about the length of the glumes; sheaths often 

 pubescent 5. B. racemosus. 



5. Plant annual, i to 2 feet high, awns much longer than the 



very narrow flowering glumes 6. B. sterilis. 



5 Plants perennial, 3 to 5 feet high, awns shorter than the 



flowering glumes, or wanting 6 



6. Spikelets awnless; panicle-branches spreading in flower, 



erect in fruit; rootstock creeping ... 2. B. inermis. 

 6. Spikelets short-awned; no creeping rootstock 



I. B. CILIATUS. 



1. Bromus ciliatus Linn. Fringed Brome-grass. 



Plate XLII. Figures 167, 168. 



An erect perennial, with culms three to four feet high, smooth; 

 sheaths striate, the upper smooth, the lower often retrorsely hairy; 

 leaves six to twelve inches long, thinly pilose on the upper sur- 

 face. Panicle expanded, the slender spreading branches scabrous. 

 Spikelets nearly an inch long, about seven- to twelve-flowered; 

 first glume very narrow, one-nerved; the second broader, three- 

 nerved, very acute; flowering glumes six to eight lines long, seven- 

 nerved, more or less clothed with appressed hairs, awned; awn 

 two to six lines long. 



In variety purgans Gray, the flowering glumes are clothed all 

 over the back with short appressed hairs. 



2. Bromus inermis Leyss. Hungarian Brome-grass. 



Plate XLIII. Figure 169. 



An erect perennial, two to flve feet high, from a creeping root- 

 stock. Sheaths striate smooth, or the lower ones pilose; ligule 

 short, lacerate; leaf blade four to eight inches long, three to four 

 lines wide, somewhat scabrous, the lower often sparingly pilose. 

 Panicle four to six inches long, erect, the scabrous, unequal 

 branches spreading in flower, becoming erect in fruit. Spikelets 

 twelve to eighteen lines long, narrowly oblong or linear, five- to 

 seven-flowered; rachilla pubescent; empty glumes unequal, the 

 acute first glume one-, the obtuse second glume three-nerved; flow- 

 ering glumes sub-carinate or rounded on the back, rather broadly 

 scarious at the obtuse or emarginate apex, awnless or very short- 

 awned. 



