530 
46. BOUTELOUA Lag. 
Spikelets with one perfect floret and one or two rudimentary florets, 
sessile, crowded on the narrow flattened rachis: spikes various, mostly 
pectinate, sometimes 1-flowered, but then distinguished by the prolon- 
gation of the rachis, distinctly alternate and usually secund on the 
common axis: empty glumes carinate or convex, the lower one shorter; 
floral glume of perfect floret 3-nerved, the nerves terminating in awns 
or awi-like teeth, usually with 2 or 4 teeth beside the awns; palet 
bidentate, or 2-awned and 4-toothed, nearly equaling the glume; rudi- 
mentary florets usually 3-awned, often with small glumes, staminate in 
one species.—Rather low annuals or perennials with slender culms and 
narrow leaves. This genus contains some of the most important for- 
age grasses on the ranges of the southwest. 
§ 1 Spikelets pectinate, numerous (more than 20) in each of the more or less faleate spikes; 
sterile floret with 8 awns and usually with small rudimentary glumes.—CHONDROSIUM, 
* Spikes always single. 
1. B. prostrata Lag. (GRAMA.) Culmsinsmall tufts, prostrate or ascending, 1 to 
3 dm. high: leaves smooth, 2 to 5 em. long: spikes 1 to 3 em. long: spikelets 4 to 
5mm. long; second empty glumes twice as long as the first and slightly exceeding 
the tloret; floral glume pubescent on the nerves, 3-lobed, the middle lobe 2-toothed ; 
the middle awn about as Jong as the glume, longer than the lateral awns; palet 
obtuse or bidentate, awnless; awns of the rudiment slightly longer than those of 
the floral glume; pedicel narrowly villous tufted at the apex.—Sandy plains, from 
the Pecos valley westward to Arizona, 
ey # 
Spikes two or more (sometimes single in No. 2). 
+ Sterile floret with small but distinet glumes at the bases of the awns. 
++ Teeth at the base of the middle awn minute; lateral awns winged below or reduced to awl- 
pointed teeth; no teeth outside the lateral awns: palet bidentate, awnless. 
== Empty glumes glabrous. 
2. B. breviseta Vasey. (GRAMA.) Culms 1 to3 dm, high, rigid from an almost 
woody perennial base: leaves distichous, involute, rigid, 2 to 4 cm. long; sheaths 
exceeding the internodes: spikes 1 to 3, 2 to 3 em. long: spikelets 3 to 4 mm. long; 
second empty glime very acute, slightly shorter than the floret; floral glume pubes- 
cent; awns about lmin. long; awns of rudiment 2 mm. long; pedicel hairy at the 
apex.—Rare, Presidio County, Texas. 
3. B.ramosa Scribn. (GrAMA.) Culms about 3 dm. high, sparingly branched, 
wiry, from a perennial knotted rootstock: leaves mostly involute, 3 to 6 cm. long: 
spikes mostly in twos, 2 to 3 cm. long, recurved: spikelets about 4 mim. long; second 
empty glume very acute, about one-fourth shorter than the floret; floral glume 
pubescent, narrow at the apex; awns less than one-half as long as the glume; pedicel 
of rudiment hairy at the apex; awns exceeding those of the floral glume.—Mountains, 
western Texas to northern Mexico, 
= = Lmpty glumes pubescent. 
4, B. oligostachys(Nutt.) Gray, (GrAMA.) Culms from 2to8& dm, high from a per- 
ennial rootstock, often branching: leaves flat except near the attenuate points: spikes 
2 tod, 2 to3 cm. long: spikelets 5 to 6 mm. long;second empty glume 3 times as long 
as the first and slightly exceeding the floret, papillose pubescent on the midnerve; 
floral glume deeply 2-cleft with a short slender tooth each side of the middle awn; 
awns 1 to 2 mm. long; awns of rudiment about $wice as long; pedicel villous 
