520 
9. S. Nealleyi Vasey. Culms 1 to 2dm. high, trom strong perennial rootstocks, 
slender, simple, rigid below: leaves rigid, involute, divaricate, 1 to 3 em. long, pilose 
at the throat: panicle 2 to 4 cm. long; branches few, ascending, about 1 cm. long, 
‘apillary like the main axis: spikelets about 1.5 mm. long, purple; first empty glume 
very narrow, small; second empty glume about equaling the floral glume and palet.— 
Rare, Brazos Santiago, southern Texas. 
weer Culms 2 tod dm, high: panicle narrowly pyramidal; branches verticillate, 5 em. long 
or less. 
10. S. argutus (Nees.) Kth, Culms tutted, 2 to 5 dm, high: leaves numerous near 
the base, mostly flat, 3 to 6 em, long; the upper one with long sheath and short 
blade, ciliate at the throat: panicle about 1 dm. long; branches spreading, the lower 
ones 4 ci. long or less, naked near the base: spikelets about 1.5 nin. long; first empty 
glume one-third as long; second empty glume equaling the floral glume and slightly 
exceeding the palet. (Vilfa arguta Nees.)—Dry sandy soil, central Texas to Arkan- 
sas and Colorado. 
11. S. junceus (Michx.) Kth. Culms slender, 5 to8 dm. high, simple: leaves mostly 
from the base, involute, 1 to 3 dm. long: panicle 1 to 2dm. long; branches 3 em. 
long or less, spreading or horizontal: spikelets nearly sessile, 3 mm. long, purple 
or brown; second empty glume twice as long as the first and about equaling the 
smooth floral glume and palet: grain oblong, in a thin pericarp, 2 mm. long. 
(Agrostis juncea Michx.)—Low sandy land, Texas to Florida. 
++ ++ ae Panicle generally large; branches alternate, often 1 dm. long: tall coarse grasses. 
= Branches closely flowered nearly to the base, except in 8. eryptandrus var. flecuosus, 
12. S. Wrightii Munro, (BuNcH GRASS. ZACATON.) Culms stout, 1 to3m., high, 
in large bunches with numerous coarse roots: leaves involute, long pointed, 3 to 6 
dm. long, ciliate at the throat; panicle 3 to6dm, long erect; branches spreading, 1 to 
2dm. long: spikelets 2 to 2.5 mm, long; first empty glume about one-half as long as 
the second and nearly equaling the floret; palet nearly as long as the floral glume; 
empty glumes usually deciduous.—In adobe soil, along streams, western Texas to 
southern California. 
13. S. cryptandrus (Torr.) Gray. Culms tufted or in bunches, 5 to 10 din. high: 
leaves 1 to 3. din, long, mostly flat; sheaths usually longer than the internodes, very 
pilose at the throat: panicle oblong or pyramidal, 1 to 3 dm. long, bursting from the 
upper sheath or often vaginate until maturity; branches 8 em, long or less: spike- 
lets 1.5 to 2mm. long; second empty glume twice as long as the first and about as 
long as the nearly equal floral glume and palet: grain about 1 mm. long. (Agrostis 
eryptandra ‘Torr,)—Low sandy land, central Texas and northward. Var, srricrus 
Scribn. has narrow dense and spike-like panicles, the branches remaining striet.— 
River valleys, western Texas to Colorado and Utah. Var. robustrus Vasey has 
robust often branching culms, numerous flat leaves (5 to 8 mm. wide, 3 to 6 dm. 
long), narrow panicle (3 to 6 dm, long), densely flowered slightly spreading branches, 
and somewhat scabrous spikelets.—Western Texas. Var. PFLEXUOSUS Thurb. has 
rather slender culins, leaves about 1 dm. long, very loose and open panicle mostly 
exserted (3 to 5 dim. long), and branches spreading, subdivided, bearing pedicellate 
scattered spikelets. (Apparently distinct enough to be a good species ).—Sand hills, 
western Texas to New Mexico, 
= = Panicle more open; branches naked below. 
14. S. airoides Torr. (BuNcH Grass.) Culns1to2m. high, in dense “bunches,” 
stout and erect, from strong rootstocks: leaves involute, slender, pointed, ciliate at 
the throat: panicle 2 to 4 dm. long, pyramidal; branches 1 dm. long or less, spread- 
ing, with divergent subdivisions: spikelets about 2 mm. long; empty glumes thin, 
