728 GRAMINE^ agkobtis 



A. Howe.im Scribn. Loosely tafted pereuaial :, sterna rather slender, . 

 1-3 feet longi.-fliigules about a line, long, usually obtuse and lacerate at tj^e 

 apex: panicle 4-8 inches long, its scabrous capillary branches 2-3 inbnea 

 long, usually spreading: empty glumes 1 line or less long, acuminate-Ian-' 

 ceolate; flowering glume lanceolate, acute, bearing a long slender bent awn. 

 on its back: palet hyaline, minute. On cliffs along the Columbia river, i 



A. seabra Willd. Sp PI. i, 370. Ste,m very slender, 1-2 feet high. 

 from a perennial i^pt, smooth: sheaths generally shorter than the inter- ^ 

 nodes :. ligules 1-2 lines. long: leaves 2-5 inches long, J^-i.|^ lines wide,': 

 usually erect roughish: panicle 6-12 inches long, usually purplish, its|; 

 capillary, branches spreading or ascending, or often drooping, the ibwer ^-P^ 

 inches long : empty glumes %,-\ line lone, acute, scabrous toward the apex 

 and on the keel; flowering glume nearly as long as the outer ones, rarely ' 

 bearing a short awii' on its back : palet very small. Common throughout 

 most parts of North America. ... J 



A. Idahoensis. Nash Bull. Torr. Bot. Club xxiv, 42. Stems cespitose^ 

 slender, 8-16 inches high, erect, bearing usually 2 distant leaves below the 

 middle: lower sheaths short, the upper one elongated: ligules 1-2 lines , 

 long, obtuse cut-toothed at the apex: leaves 2-5 inches.long, erec;|^ acu- 

 minate at the apex, rough on the margins : panicle oblong 3-6 inches,1^ng. 

 its branches and pedicels scabrous above : empty glumes lanceolate and 

 acuminate, about 1 line long, scabrous on the keel, the first longer'than 

 the second: flowering gliime about 5^ as long as the outer ones: palet 

 wanting. In forests, Idaho. 



A. varlang iTrin,. Agrost. ii, 68. Stems slender, erect, (}>)iisel}«cespi- 

 tose, 3-10 inches :high : sheaths longer than the internodes ; uppej(ligule 

 about % line long, acutish : leaves very narrow, slightly scabrous^^^ove : 

 panicle 1-2 inches, long, dark purple, its branches an inch or les^'^ng, 

 erect or ascending: empty glumes nearly equal, roughish on the keel 

 toward the apex, subacute; .flowering glume nearly as long as the outer 

 ones, 2-toothed at the ape^, awnless : palet wanting. In wet places on the 

 high mountains, Washington tu California. 



A. Oregonensis Yasey. Stems slender, erect, 1-2^ feet high, frpm'a- 

 perennial root; leaves flat, 2-3. inches long, the upper one ugually longest : 

 ligules 1-2 lines long, acute : panicle long-exsertea, 2-4 inches long, 'dark 

 purple, narrow, its capillary bf^hches 1-2 inches long, erect : empty glumes 

 lanceolate, acuminate, about 1 line long; flowering glume hyaline, about' 

 % as long as the outer ones, acute, not awned : palet wanting. In moist 

 meadows about the base of Mount Hood) Oregon. ... 



A.- ' hnmilis Vasey Bull. Torr. Bot. Clul) x,-21. Stems densely cespi- 

 tose, 2-6 inches hifeh, frqiii' perennial roots: sheath usually Only one, 

 about Ji as long as the.-^tfem: ligules auriculate or 3-lobed, ^ line long: 

 leaves mostly basal, 1-^ 'inches longj less than a line wide, erect : pani^^e 

 narrow, 6-18 lines long,-iJaTk' purple]? its very few branches erect or appres- 

 sed: empty glumer equal; laticeome,'. acute, smooth, %-\ line loti^i flttvf- 

 ering glume nearly equalliii'g tbe outer ones, lanceolate, minutely toothM 

 at the apex: palet ovate-oblong. In wet meadows on high mountains, 

 Washington to the Rocky Mountains. 



A. Tirescens HBK. Nov. Gen. a, 135. Stems 1-2 feet high^ from ,a 

 perennial root :.!SheathB( much ighorter than thei internodes m'ostly.'jamooth : 

 ligules more tbail^a line:46ng, truncate : leaves flat,; :erect, about 6 inches 

 long by 4 l)ne8iwide;*ough on both sides: panicle pale greenish tinged 

 with purple, about 6 inches, long, its branches in clusters about an inch 

 apart on the common axis : empty glumes very acute, the lower terminated 

 by' a distinct seta, rough on the keel and pubescent all over; flowering 

 glume about ^ ' shorter than the empty ones, bearded at base; by a few 

 short white hairs, 6-nerved, the lateral nerves .projecting as distinct <ieetbi 



