

POACEAE. 



. awn. Sparingly escaped from cultivation. 



46. MERATHREPTA. 



Rowers solitary or few in a small raceme or panicle; spikelets 



. many-flowered, the flowers all perfect or the upper staminate; 



rachilla pubescent, extending beyond the flowers; glumes keeled, 



acute, subequal, persistent, generally extending beyond the 



uppermost lemma; lemmas rounded on the back 2-toothed, 



deciduous, ths bent awn flat and twisted at the base arising 



from between the acute or awned teeth; palea hyaline, 2-keeled 



ir tlu> margins, obtuse or 2-toothed; grain free, enclosed in the 



h mm. i. 



Soik. 1, t a in small racemes; leaves merely scabrous. M. californica. 



teleta mostly solitary- leaves hairy. M - unispicata. 



Merathrepta californica (Boland.) Piper. Erect, 50-100 cm. tall; leaf 

 ibrous; sheaths loose, shortly retrorse-pubescent, with a tuft 



bain .it the throat; spikelets 1-2 cm. long, 3-5 in a raceme, rarely more 

 numerous or even solitary, usually long-pedicelled ; lemma long-cihate below 

 the middle, two cleft at apex, bearing an awn of about equal length. Common 

 in low places. 



Merathrepta unispicata (Thurb.) Piper. Closely resembling M. californica 

 but not so large, 15-30 cm. tall; leaf blades sparsely hairy, the sheaths villose 

 with long white hairs; spikelets small, solitary. In dry soils, rare. 



47. AVENA. Oats. 



Annuals with large spikelets; inflorescence a panicle; spike- 

 lets - 1 many-flowered; lower flowers perfect, the upper often 

 iminate; glumes somewhat unequal, membranous, psrsistent; 

 lemmas deciduous, rounded on the back, acute, generally bearing 

 dorsal awn; apex often 2-toothed; palea narrow, 2-toothed; 

 in oblong, deeply furrowed, enclosed in the lemma and palea, 

 <»r sometimes adheren: to the latter. 



Avena fatua glabrata Petermann. Smooth Wild Oat. Stems stout, pale, 

 th, 50 100 cm. tall, erect; leaf blades broad and flat, the sheaths about 

 the internodes; panicle loose 15-30 cm. long; spikelets, including 

 1 ( in. long, erect or drooping, on slender branches; lemma smooth, 

 >rous apex and the ring of stiff white hairs at the base, bearing 

 on the back a geniculate, stout, twisted awn below the 2-cleft apex. A trouble- 

 in cultivated land. 



48. DESCHAMPSIA. 



Annuals or perennials; inflorescence a contracted or open 



aide; Bpikelets 2-flowered, both flowers perfect, the hairy 



ending txyond the flowers or rarely terminated by a 



laminate one; glumes keeled, acute, membranous, shining, 



