728 GRAMINEZ AGROSTIS 
A. Howellii Scribn. Loosely tufted perennial: stems rather slender, 
1-2 feet long: ligules about a line long, usually obtuse and lacerate at the 
apex: panicle 4-8 inches long, its scabrous capillary branches 2-3 inches 
long, usually spreading: empty glumes 1 line or less long, acuminate-lan- 
ceolate ; flowering glume lanceolate, acute, bearing a long slender bent awn 
on its back: palet hyaline, minute, On cliffs along the Columbia river. 
A. scabra Willd. Sp Pl. i, 370. Stem very slender, 1-2 feet high, 
from a perennial root, smooth: sheaths generally shorter than the inter- 
nodes: ligules 1-2 lines long: leaves 2-5 inches long, 1-11 lines wide, 
usually erect. roughish: panicle 6-12 inches long, usually purplish, its 
capillary branches spreading or ascending, or often drooping, the lower 3-6 
inches long: empty glumes 34-1 line long, acute, scabrous toward the apex 
and on the keel; flowering glume nearly as long as the outer ones, rarely 
bearing a short awn on its back: palet very small. Common throughout 
most parts of North America. 
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, erect, acu- 
minate at the apex, rough on the margins: panicle oblong 3-6 inches long, 
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 glume about #4 as long as the outer ones:- palet 
wanting. In forests, Idaho. . ) 
A. varians Trin. Agrost. ii, 68. Stems slender, erect, densely cespi- 
tose, 3-10 inches high: sheaths longer than the internodes: upper ligule 
about 4 line long, acutish: leaves very narrow, slightly scabrous above: 
panicle 1-2 inches long, dark purple, its branches an inch or less long, 
erect or ascending: empty glumes nearly equal, roughish on the keel 
toward the apex, subacute; flowering aiuAe nearly as long as the outer 
ones, 2-toothed at the apex, awnless: palet wanting. In wet places on the 
bigh mountains, Washington tu California. 
A. Oregonensis Vasey. Stems slender, erect, 1-2 feet high, froma 
perennial root: leaves flat, 2-3 inches long, the upper one usually longest: 
ligules 1-2 lines long, acute: panicle long-exserted, 2-4 inches long, dark 
purple, narrow, its capillary branches 1-2 inches long, erect: empty glumes 
lanceolate, acuminate, about 1 line long; flowering glume hyaline, about 
34 as long as the outer ones, acute, not awned: palet wanting. In moist 
meadows about the base of Mount Hood, Oregon. 
A. humilis Vasey Bull. Torr. Bot. Club x, 21. Stems densely cespi- 
tose, 2-6 inches high, from perennial roots: sheath usually only one, 
about 144 as long as the stem: ligules auriculate or 3-lobed, % line long: 
leaves mostly basal, 1-3 inches long, less than a line wide, erect:: panicle 
narrow, 6-18 lines long, dark purple, its very few branches erect or appres- 
sed: empty glumes equal, lanceolate, acute, smooth, 34-1 line long; flow- 
ering glume nearly equalling the outer ones, lanceolate, minutely toothed | 
at the apex: palet ovate-oblong. In wet: meadows on high mountains, 
Washington to the Rocky Mountains. 
As virescens HBK. Nov. Gen. i, 135. Stems 1-2 feét high, from a 
perennial root: sheaths much shorter than the internodes mostly smooth: 
ligules more than a line long, truncate:. leaves flat, erect, about:.6 inches 
ony by 4 lines wide, rough 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 ovér; flowering 
glume about 14 shorter than the empty ones, bearded at base by a few 
short white hairs, 5-nerved, the lateral nerves, projecting as distinct teeth, 
