46 
monly curved, cauline, about 3,similar, panicle spike-like, close, 4 to 6 inches long, 
purple, lower branches mostly in pairs, unequal, the longer about 1 inch long, all 
appressed ; lower glume 4 lines and upper about 6 lines long, flowering glume 5 to 6 
lines long, gradually tapering above, smooth; awns 8 to 10 lines long, smooth, nearly 
equal,—Texas (J. Reverchon, G. C. Nealley). 
Var. auGusTA, panicle narrow, otherwise nearly the same.—Comanche Peak ( Rever- 
chon), Texas (G. C. Nealley), This species approaches closely A. purpurea, but 
appears to be sufficiently distinct. 
* * * Panicle loose, branches mostly short. 
14. A. purpurascens Poir. (Gray’s Manual, 6th ed., p. 641.) Perennial ? Culms 2 
to 3 feet long, smooth, rarely branching; leaves long, becoming involute; panicle 
spike-like, erect or nodding, 10 to 18 inches long, closely flowered, lower branches 1 
to 2 inches long, appressed; lower glume about 5 lines, upper 4 lines long, both 
1-nerved, flowering glume 3 lines long, spotted; middle awn about 1 inch long, lat- 
eral ones 9 to 10 lines; stipe short, narrowed to the sharp point.—Massachusetts to. 
Kansas, south to Texas and Florida. 
Var. MINOR Vasey. Culms more branching, panicle thinner and more flexuous, 
flowers and awns rather shorter.—Southern States to Texas. 
15. A. oligantha Michx. (Gray’s Manual, 6th ed., p. 640.) Culms 1 to 2} feet high, 
tufted, from a perennial root, much branched, panicles lateral and terminal, a nearly 
simple loose raceme 3 to 5 inches long, the branches rar: ly sessile, the lower in pairs, 
few-flowered; empty glumes nearly equal, 10 to 12 lines long, floral glume 7 to 9 
lines long, long-tapering above, awns capillary, 14 to 3 inches long.—Maryland to 
Kansas, south to Florida and Texas, also on the Pacific coast. 
16. A.lanata Poir, (Gray’s Manual, 6th ed., p. 641.) Perennial, culms tall and 
stout, 2 to 4 feet long, leaves flat, 1 to 2 feet long, long-pointed, rough on upper side, 
sheaths woolly; panicle 1 to 2 feet long, nodding, loosely spike-like, with the branches 
somewhat spreading, the lower unequal, 1 to 2 inches long, rather remote, some- 
what woolly in the axils; lower glume 7 to 8 lines long, upper one 4 to 4} lines, 
both 1-nerved; flowering glumes 5 lines long, stipe short. smooth, middle awn 
spreading, 9 lines long, lateral ones about 5 lines long.—Delaware to Florida. 
17, A. dispersa Trin. & Rupr. Gram. Agrost., p.129. Annual? Culms branching, 
of variable height, panicle 1 to 6 inches long, contracted, generally purplish, lowe 
branches mostly in twos or threes, unequal (4 to 1 inch), flowering nearly to the 
base; glumes unegual or nearly equal, lower 3 to 4 lines, upper 4 to 5 lines long : 
flowering glume about 3 lines; awns nearly equal,5 to 8 lines long, spreading.— 
Texas to California. . 
18. A. purpurea Nutt. (Gray’s Manual, 6th ed., p. 640.) This species was defined 
by Nuttall in the Trans, Amer. Philos. Society, Vol. v. new series, 1837, and is practi- 
cally as follows: Panicle rather erect, slender; empty glumes aristulate, bifid at 
apex; awns capillary, very long; leaves short scabrous; perennial, leaves narrow, 
short and scabrous, ligale pilose; culms about 1 foot high, panicle many flowered, a 
little spreading, branches capillary, flowers vommonly in pairs, bluish-purple; one 
of the glumes nearly twice the length of the other, the longer glume exceeding the flow- 
ering glume; awns equal, capillary, nearly three times the length of the flowering 
glume and scabrous, the flowering glume minutely stipitate.—On the grassy plains 
of the Red River in arid situations. 
This is one of the most variable species we have, and has a wide distribution in the 
West and Southwest. Our present acquaintance with the genus requires its division 
into several varieties; indeed Trinius found it necessary to make two varieties, and 
one or two more are needed to complete the species, 
Var. FENDLERIANA. (A. Fendleriana Steud.) Perennial, culms tufted, 8 to 12 
inches high, very slender and erect, branching near the base; radical leaves 
abundant, nearly capillary, involute, 3 to 4 inches long, those of the culm about 3, 
