Avena. | LXXXIX,. GRAMINEA. j 523 
regions of both hemispheres, or in the higher mountains within the 
tropics, 
Annual. Spikelets hanging, 8 to 10 lines long. P 4 : . L. A. fatua. 
Perennial. Spikelets erect or spreading. 
Spikelets about 6 lines long . , : ‘ é ; ; . 2 A. pratensis. 
Spikelets about 3lineslong . ; : ; . 3&8. A. flavescens. 
1. A. fatua, Linn. (fig. 1198). Weld O.—An erect, glabrous annual, 
2 to 3 feet high, with a loose panicle of large spikelets, hanging from 
filiform pedicels of unequal length, arranged in alternate bunches along 
the main axis. Outer glumes nearly ? inch long, pale-green or purplish, 
tapering to a thin, scarious point. Flowering glumes 2 or 3, scarcely so 
long as the outer ones, of a firm texture at the base, and covered out- 
side with long, brown hairs, thin and cleft at the top, each lobe taper- 
ing into a short point. Awn fully twice as long as the spikelet, twisted 
at the base, abruptly bent about the middle. 
A common weed of cultivation in all corn countries, and generally 
confined to cornfields, so that its origin is as yet doubtful, but probably 
a native of the east Mediterranean region. Abundant in Britain. FV. 
with the corn. <A variety with the flowering glumes larger and more 
like the outer ones, hairy only below the middle, and terminating in 2 
-almost awn-like points, has been distinguished as A. strigosa, Schreb., 
and it is said that the cultivated Oat is but a variety of the same 
species, readily degenerating into the wild form. This, however, 
requires proof. 
2. A. pratensis, Linn. (fig. 1199). Perennial O.—An erect peren- 
nial, with a tufted or shortly creeping rootstock, 1 to 14 feet high, 
with narrow leaves in dry pastures, but in rich mountain meadows 
attaining often 3 feet high, the leaves then broader, with much flat- 
tened sheaths. Panicle either slightly compound or reduced to a 
simple raceme. Spikelets erect, usually 3 or 4-flowered, glabrous and 
shining. Glumes all scarious at the top; the outermost empty one 
about 6 lines long, tapering to a point; the second similar but rather 
longer ; the flowering ones gradually smaller, shortly cleft at the point, 
with an awn on the back fully twice their length. 
In meadows and pastures, especially in hilly districts, throughout 
Europe and Russian Asia, except the extreme north. Widely distri- 
buted over Britain, but not very common. fl. summer, rather early. 
A, alpina, Sm., is a luxuriant mountain form, with more or less flat- 
tened sheaths to the leaves, formerly confounded with the Continental 
A. planiculmis, Schrad. A more marked variety, not uncommon in dry 
districts, is A. pubescens, Huds.; it has the leaf-sheaths more or less 
downy, rather smaller spikelets, and the hairs on the axis of the spike- 
let between the florets much longer. 
3. A. flavescens, Linn. (fig. 1200). Yellow O.—An erect perennial, 
1 to 2 feet high. Panicle oblong, 3 to 5 inches long, with slender, 
somewhat spreading branches and pedicels. Spikelets erect, shining, 
and often of a yellowish hue, not half the size of those of A. pratensis. 
Glumes all scarious, the 2 outer empty ones very unequal. Flowering 
glumes usually 4 or 5, cleft into 2 points; the awn twisted and bent as 
in the last two species, but short, and very fine and hair-like. Tvrisetwm 
flavescens, Beauv. 
In rather dry meadows and pastures, in temperate and southern 
