52 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



Figuee 34. — Bromus arvensis, X 1. (Gray, Aid.) 



Figure 35. — Bromus arenarius, X 1. (Pendleton 1459, Calif.) 



straight or nearly so in drying; palea 

 as long as the lemma or only slightly 

 shorter. O — Open ground, culti- 

 vated soil, New York, Maryland; 

 North Dakota, Nevada, Arizona, and 

 California. 



36. Bromus arenarius Labill. Aus- 

 tralian chess. (Fig. 35.) Culms 

 slender, 15 to 40 cm. tall, sheaths and 

 blades pilose; panicle open, pyram- 

 idal, nodding, 8 to 11 (rarely 15) cm. 

 long, the spreading branches and 

 pedicels sinuously curved; glumes 

 densely pilose, acute, scarious-mar- 

 gined, the first narrower, 3-nerved, 8 

 mm. long, the second 7-nerved, 10 

 mm. long; lemmas densely pilose, 7- 

 nerved, 10 mm. long; awn straight, 10 

 to 16 mm. long.. O — Sandy road- 

 sides, gravelly or sterile hills, Oregon, 

 California, Nevada, and Arizona; ad- 

 ventive at Philadelphia, Pa.; intro- 

 duced from Australia. 



Bromus alopecuros Poir. Weedy 

 annual 20 to 40 cm. tall; foliage softly 

 pubescent; panicle narrow, dense, 5 

 to 10 cm. long; spikelets short- 

 pedicellate, about 2 cm. long, the 



glumes and lemmas softly pubescent, 

 the awn of the lemma, flat, twisted at 

 the base, spreading, 1.5 to 2 cm. long. 

 O — Adventive in waste ground, 

 Ann Arbor, Mich. Mediterranean 

 region. 



Section 4. Eubromus Godr. 

 Tufted annuals; spikelets compressed; 

 glumes and lemmas narrow, long- 

 awned; first glume 1-nerved, the 

 second 3-nerved; lemma 5- to 7- 

 nerved, cleft at the apex, the 

 hyaline teeth 2 to 5 mm. long; 

 floret at maturity with a sharp 

 hard point or callus. Introduced 

 from Europe. 



37. Bromus rigidus Roth. Ripgut 

 grass. (Fig. 36.) Culms 40 to 70 cm. 

 tall; sheaths and blades pilose; panicle 

 open, nodding, rather few-flowered, 7 

 to 15 cm. long, the lower branches 1 

 to 2 cm. long; spikelets usually 5- to 

 7-flowered, 3 to 4 cm. long, excluding 

 awns; glumes smooth, the first 1.5 to 

 2 cm. long, the second 2.5 to 3 cm. 

 long; lemmas 2.5 to 3 cm. long, sca- 

 brous or puberulent, the teeth 3 to 4 



