54 



GRAMINEL/E. 



2. A. sativa L. Common Oat.-;. Near to A. fatua, but distin- 

 guished by its usually shorter stature, by the 7-nerved bractlet being 

 glabrous (or bearing a few long hairs at the base), and by the often 

 short, straight awn which is sometimes obsolete. 



Frequently found as an escape in the borders of fields and by the 

 roadside: Berkeley; Briones Hills. 



3. A. barbata Brot. Barbed Oats. Stems slender, erect, 2 to 

 Sh ft. high; uppermost ligule 1 to 1£ lines long, broad, obtuse, trun- 

 cate, irregularly notched; blades 1 to 3? lines broad, scabrous on both 

 surfaces; panicle usually 6 to 12 in. long, shorter in dry localities and 

 Reasons; branches few at a node, very unequal, long and filiform; 

 spikelets 2 to several-flowered, narrow and slender; bracts subequal, 

 oval-lanceolate, setaceous-pointed, 10 to 12 lines long, with 7, 9 or 11 

 broadly green-margined nerves; margins scarious, shining; bractlet 

 10 to 12 lines long, including the long, slender, awn-pointed teeth, 

 2£ lines wide, lanceolate, membranaceous, clothed with soft, silky, 

 usually white hairs, 7-nerved; awn from near the middle of the 

 bractlet. stout, geniculate, 11 to 20 lines long; palea 6£ lines long, 1 

 line wide, with short divergent hairs on the nerves; anthers 1£ lines 

 long; ovary densely hairy with long, white, silky, erect hairs. 



A montane species, native of S. Europe and naturalized extensively 

 in California in the Coast Range hills, and Southern California: San 

 Jose, Brainard, Lake Merced, Olema, Angel Island, Point Isabel, 

 Livermore, Berkeley. Mar. -Aug. Often mistaken for A. fatua, 

 from which it may be distinguished without difficulty, when once 

 known, by its more slender inflorescence and spikelets. 



21. ARRHENATHERUM Beam. 



Perennial, usually tall grasses. Leaf-blades flat. Spikelets terete, 

 strictly 2-flowered; rachilta jointed between the flowers, often hairy, 

 prolonged beyond the insertion of the uppermost bractlet as a short 

 point or bristle; lower flower staminate, upper pistillate or perfect. 

 Bracts persistent, scarious (in ours), very unequal, shortly acuminate, 

 keeled. Bractlets rigid, 5 to 7-nerved, "2-toothed, that of the lower 

 flower with a long, basal, bent and twisted awn, that of the upper with 

 a short, dorsal awn; palea 2-nerved. Scales lanceolate, laterally 

 toothed. Stamens 3. (Greek arrhen, masculine, ather, awn; only 

 the male flower is conspicuously awned.) 



1. A. elatius (L.) Beauv. Tall Oat-grass. Rootstock peren- 

 nial, widely creeping; stems 2 to 4 ft. high, erect, slender, smooth, 

 leafy, often densely tufted; lowest internode sometimes developed into 

 a conn; leaves bright green; sheaths smooth; ligule broad, obtuse, 

 about 1 line long; blades soft, minutely scabrid, 2£ to 3£ lines wide; 

 panicle narrow, pale green, shining, 6 to 8 in. long, drooping; 

 branches short, erect, scabrid, spreading in flower, densely whorled, 

 bearing few spikelets; spikelets 3 to 4 lines long; upper bract enclos- 

 ing the 2 flowers, acute; lower much smaller; bractlet hairy below, 

 about half as long as the twisted, bent awn. — (A. avenaceum Beauv.; 

 Avena elatior L.) 



