50 POACEAE. 



imperfect; glumes 2, subequal, membranaceous with broad scari- 

 ous margins, rounded on the back, shorter than the flowers; 

 lemmas 5-many-nerved, cordate at base, awnless; palea much 

 smaller than the lemma, obtuse; styles short, distinct; stigmas 

 plumose. 



Briza media L. Perennial, tufted; stems erect, of various lengths, 10-60 

 cm. high on the same plant; leaf blades scabrous; panicle loose, pyramidal, 

 5-10 cm. long; spikelets ovate to cordate, 6-8 mm. long, 5-9-flowered. 



Sparingly introduced from Europe. Reported from Nanaimo, Vancouver 

 Island, Macoun. 



78. BROMUS. Brome-grass. 



Annuals, biennials or perennials with flat leaves and terminal 

 panicles of large spikelets; peduncles thickened at the summit; 

 spikelets few-many-flowered; glumes unequal, acute; lemmas 

 rounded on the back, or sometimes compressed-keeled, 5-9- 

 nerved, the apex usually 2-toothed, generally bearing an awn 

 from just below the summit; palea shorter than the lemma; 

 grain adherent to the palea. 



Spikelets strongly flattened; perennials. 



Awns less than 7 mm. long; leaves linear-lanceolate, flat, 



not pilose. B. marginatus. 



Awns more than 7 mm. long. 



Panicle very broad, the longest rays 15-25 cm. long, 



drooping. B. sitchensis. 



Panicle large but the rays not drooping. B. hookerianus. 



Spikelets subterete, not strongly flattened. 



Native perennials mostly with loose and drooping panicles; 

 lemma usually more or less long-hairy. 

 Panicle narrow, erect or nearly so. B. vulgaris. 



Panicle broad, drooping. 



Lemma evenly pubescent. B. pacificus. 



Lemma unevenly pubescent. B. richardsonii. 



Introduced annuals or biennials. 



Awns much longer than the body of the narrow lemma. 

 Lemma pubescent or rarely glabrous; awns 13-15 



mm. long. B. tectorum. 



Lemma not pubescent; awns 18-45 mm. long. 



Awns 35-45 mm. long B. maximus. 



Awns less than 30 mm. long. 



Panicle a dense head-like cluster. B. rubens. 



Panicle loose. B. sterilis. 



Awns shorter than or scarcely exceeding the broad 

 lemma. 

 Panicle dense, small. B. hordeaceus. 



Panicle loose, open. 



Margins of the lemma inrolled in fruit. B. secalinus. 



Margins of the lemma not inrolled in fruit. B. commutatus. 



Bromus marginatus Nees. Perennial, tufted; the stout stems about 1 m. 

 high; leaf blades coarse, sparsely pubescent; panicle 15-25 cm. long, rather 

 narrow, the branches in whorls of 2-4, about 7 cm. long, and bearing two 

 spikelets; spikelets 2.5-4 cm. long, 5-7 mm. wide, compressed and keeled, 



