192 
GRAMINEAE 
Sheaths and lemmas glabrous; margin of lemma inrolled toward the 
base at maturity, the rachilla partly visible .. 6. B. secalimis. 
. Sheaths pubescent; margins of lemmas not inrolled or rarely. 
Panicles nodding, the branches and oedicels not elongated and 
flexuous ; awn usually not over % as long as the broad 
glabrous or scaberulous lemma.7. B. commutatus. 
Panicles dropping, the branches and pedicels flexuous; awns 
mostly as long as the body of the narrower lemma or 
longer...8. B. arenarius. 
Plants perennial; panicle open, the branches spreading or drooping. 
Spikelets strongly flattened, the lemmas strongly keeled toward the summit; 
spikelets awned; blades flat, glabrous or somewhat pilose. 
Awn less than 7 mm. long ; blades rather broad.9. B. marginatus. 
Awn more than 7 mm. long; blades usually narrow.10. B. carinatus. 
Spikelets not strongly flattened, the lemmas not keeled ; first glume 1-nerved ; 
lemmas sparsely pubescent on back, ciliate on margins or nearly 
glabrous...11. B. vulgaris. 
1. B. tectorum L. Downy Brome. Culms tufted, 3 to 6.5 dm. high, 
the whole plant softly pubescent; panicle many-flowered, loose, drooping, 
commonly % the entire height of the plant; spikelets 1.5 to 2 cm. long, 
nodding; lemmas pubescent; awn 1.2 to 1.5 cm. long.—Waste places; nat. 
from Mediterranean region. Var. nudus Klett & Richt. Spikelets gla¬ 
brous.—The common form in Cal. 
2. B. rubens I. Red Brome. Culms 1.5 to 3.8 dm. high, puberulent 
below the panicle: sheaths and blades pubescent; panicle erect, compact, 
ovoid, usually purplish, 4 to 8 cm. long; spikelets 7 to 11-flowered, about 
2 cm. long; lemmas 5-nerved, pubescent or smooth, 1.2 to 1.5 cm. long, 
the apex deeply cleft into 2 long-acuminate hyaline teeth ; awn about 
2 cm. long.—Dry hills and in waste or cultivated ground; common 
especially in middle and S. Cal.: nat. from s. Eur. 
3. B. madritensis L. Culms tufted, 3 to 6 dm. high; sheaths smooth 
or the lower slightly pubescent; blades puberulent or nearly smooth; 
panicle erect, 4 to 8 cm. long, oblong-ovoid in outline, contracted, rather 
dense; lemmas 1.5 to 1.8 cm. long, usually glabrous or scabrous only, 
somewhat curved outward when old, distinctly 3 or faintly 5 to 7-nerved, 
with 2 acute hyaline teeth; awn rather stout, tapering, somewhat curved, 
1.6 to 2.2 cm. long.—Open ground and waste places; nat. from Eur. 
4. B. rigidus Roth. “Ripgut” Grass. Culms 4.5 to 7.5 dm. high; 
sheaths and blades pilose; panicle open, rather few-flowered, 6 to 10 cm. 
long; spikelets usually 5 to 7-flowered, 3.5 to 5 cm. long; lemmas 5- 
nerved, scabrous or puberulent, 2-toothed; awn stout, 3.5 to 5 cm. long.— 
Weed in open ground and waste places, nat. from Mediterranean region. 
Var. gussonei (Pari.) Coss. & Dur. Differs in having a more open 
panicle, and longer flexuous branches and pedicels, the lower branches 
as much as 10 to 12 cm. long.—More common than the species in mid. 
and n. Cal.; nat. from s. Eur. At maturity nos. 2 to 4 are injurious to 
grazing animals; the disjointed sharp-pointed florets with their long 
rough awns penetrate the eyes, nose and mouth parts, causing sores and 
blindness. 
5. B. hordeaceus L. Soft Cheat. Culms 2 to 7.5 dm. high; sheaths 
retrorsely softly pilose; blades usually pubescent; panicle contracted, erect, 
5 to 10 cm. long, or in depauperate plants reduced to a few spikelets; 
