531 
tufted, (Atheropogon oligostachyus Nutt.)—Dry hillsides, Texas to Wisconsin and 
westward to Montana and Arizona. Var. MAJOR Vasey has spikes 4 to 6 em. long 
and spikelets 6 to 7mm. long.—Texas to Arizona, 
5, B. hirta(HBK.) Seribn. (Harry Grama.) Culms3to5 dm. high, usually simple 
above the base, in perennial tufts; leaves flat, slender-pointed, thinly papillose pubes- 
cent near the base, 1 to 2 dm. long: spikes 2 to 6, 2 to4 cm. long; rachis prominently 
prolonged beyond the upper spikelet: spikelets 3.5 to 4.5 mm, long; second outer 
elume papillose pubescent, twice as long as the first, nearly as long as the floret; 
floral glume pubescent, deeply 2-cleft, the lateral lobes merely awn-pointed, the 
middle lobe 2-toothed at the base of the short awn; pedicel of rudiment naked; 
awns3to 5 mm. long. (Chondrosium hirtum HBK. Bouteloua hirsuta Lag.)—Prai- 
ries, Texas to Wisconsin and westward to California, Var.MAJOR Vasey is larger 
(5 to8 dm. high), with spikelets nearly 6 mm. long, longer awned than in the 
species, and sterile pedicel sometimes slightly hairy.—Prairies, western Texas to 
Mexico. Var. Minor Vasey is slender (1 to 3 dm. high), with 1 to 8 spikes 1 to 2 
em. long, and spikelets 3 to 4 mm. long.—Central Texas, 
a+ ++ Teeth at the base of the middle awn nearly one-half as long as the awn, or equaling 
it; lateral awns naked to the base; lateral teeth outside the lateral awns more or 
less distinet: palet 4-toothed, short awned from the lateral sinuses. 
= Hinpty glumes glandular pubescent, 
6. B. vestita(Watson.) Scribn. in Herb. (GRamMA.) Culms3 to 6dm. high: leaves 
mostly flat, thinly pubescent: spikes 4 to 6, about 2 cm. long, at intervals longer than 
themselves; rachis pubescent: spikelets 3.5 to 4.5 mm. long; second empty glume 
awn-pointed between the small unequal lobes, twice as long as the first glume and 
slightly exceeding the floret; floral glume thinly pubescent at the base and on the 
nerves; inner lobes larger, minutely ciliate; awns from the sinuses equaling or slightly 
longer than the giume; palet minutely ciliate on the four equal lobes, short awned; 
sterile pedicel pilose tufted, bearing three awns equaling those of the perfect 
floret.—Ravines and mountains, western Texas. 
= = Lmpty glumes glabrous. 
a. Upright, perennial. 
7. B. Rothrockii Vasey. (Grawa.) Culms 3to6din. high, sometimes branching 
near the base: leaves mostly flat, 5 to 10 em. long, thinly pubescent near the base: 
spikes 4 to 10, 2t03 em. long: spikelets 3 to4mm, long; second outer glume promi- 
nently mucronate between the two unequal lobes, much larger than the first but 
shorter than the floret; floral glume deeply 4-lobed; the lobes subacute, nearly 
equal, minutely ciliate; awns equaling or longer than the ghune; teeth of the palet 
ciliate; awns slightly shorter than those of the glume; awns of the rudiment 
usually longer; pedicel villous tufted,—Dry mesas, Arizona and Mexico and doubt- 
less extending into western Texas. 
b. Spreading or prostrate, annual, 
8. B. microstachys (Fourn.) (GRama.) Culms 1 to 2 dm. high usually branch- 
ing: leaves flat, narrowly lance-linear, 2 to 5 em, long: spikes 3 to 6, about 2 cm. 
long, slightly exceeding the intervals: spikelets 2.5 to 3.5 mm, long; second outer 
glume much longer than the first, about equaling the floret, mucronate; floral 
glume deeply 4-lobed, the outer lobes smaller, often inconspicuous, inner ones sub- 
acute; awns equaling or longer than the glume; awns of the acutely 4-toothed 
nalet and the pilose pedicelled rudiment nearly as long as those of the gluines. 
(Chondrosium microstachyum Fourn., B. arenosa Vasey, in “Grasses of the Southwest.” 
B, polystachys Benth, in part.)—Sandy river banks, western Texas to southern Cali- 
fornia. 
