Avena. | LXXXIX. GRAMINEH. 521 
twisted, and bent awn on the back of the glume, The terminal glume of 
the spikelet often small and empty or rudimentary. Axis of the spikelet 
hairy under the flowering glumes. 
A considerable genus, widely spread over the temperate and colder re- 
gions of both hemispheres, or in the higher mountains within the tropics. 
Annual. Spikelets hanging, 8 to 10 lines long. : > - . lL. A. fatua. 
Perennial. Spikelets erect or spreading. 
Spikelets about 6lineslong . A ; P ; A A . 2. A. pratensis. 
Spikelets about 3lineslong . : ° ° ; . . o. A. flavescens. 
1, A. fatua, Linn. (fig. 1194). Wild Oat.—An erect, glabrous annual, 
2 to 3 feet high, with a loose panicle of large spikelets, hanging from fili- 
form pedicels of unequal length, arranged in alternate bunches along the 
main axis. Outer glumes nearly 3 inch long, pale-green or purplish, taper- 
ing 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 outside with 
long, brown hairs, thin and cleft at the top, each lobe tapering 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 con- 
fined to cornfields, so that its origin is as yet doubtful, but probably a 
native of the east Mediterranean region. Abundant in Britain. Fl. 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 under the name of 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 further 
proof, 
2. A. pratensis, Linn. (fig. 1195). Perennial Oat.—An erect peren- 
nial, with a tufted or shortly creeping rootstock, 1 to 12 feet high, with 
narrow leaves in dry pastures, but in rich mountain meadows attaining 
often 3 feet high, the leaves then broader, with much flattened sheaths. 
Panicle either slightly compound or reduced to a simple raceme. Spike- 
lets erect, usually 3- or 4-flowered, glabrous and shining. Glumes all 
- searious at the top; the outermost empty one about 6 lines long, tapering 
to a point; the second similar but rather longer; the flowering ones 
eradually 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 distributed over 
Britain, but not very common. FY. summer, rather early. Luxuriant 
mountain specimens, with more or less flattened sheaths to the leaves, 
have been distinguished as a species, under the name of A. alpina, Sm., 
and confounded with A. planiculmis, Schrad. A more marked variety, 
not uncommon in dry districts, is generally distinguished under the name 
of A. pubescens, Huds. It has the leaf-sheaths more or less downy, rather 
smaller spikelets, and the hairs on the axis of the spikelet between the 
florets much longer. 
3. 4. flavescens, Linn. (fig. 1196). Yellow Oat.—An erect peren- 
nial, 1 to 2 feet high. Panicle oblong, 3 to 5 inches long, with slender, 
somewhat spreading branches and pedicels. Spikelets erect, shining, 
