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pubescent, oblong, cleft to the middle. (Uralepis pulchella Kth.)—Dry sandy mesas, 
western Texas to southern California, Var. PARVIFLORA Vasey is slender, with 
florets 2 to 3mm. long.—Western Texas. 
* Spikelets compressed, crowded in short subcapitate panicles on the simple nearly naked 
culms, bleaching white at maturity: leares short, blunt-pointed, strongly keeled. 
+ Floral glume entire or merely mucronate. 
2. S. acuminata (Munro) Kuntze. Culms 1 to 3 dm. high, erect, tufted from a 
perennial rootstock: spikelets 4 to 8, about 1 cm. long; empty glumes smooth, acute, 
shorter than the contiguous florets; floral glumes broadly lance-ovate, subacute, or 
somewhat acuminate, mucronulate, pubescent, twice as long as the broad palet 
(Tricuspis acuminata Munro.)—Dry gravelly soil, Texas to Arizona, 
+ + Floral glume deeply cleft at the apex; awn from the sinus exceeding the lobes. 
++ Floral glume lance-ovate; lobes subacute. 
3 S. avenacea (HBK.) Kuntze. Culms 2 to 3 dm. high from a stoloniferous base: 
panicle 3 to5 em. long: spikelets 6 to 8 mm. long, 5 to &-flowered; empty glumes 
nearly equaling the lower florets; floral glume oblong, prominently ciliate near the 
base on the nerves; palet about one-half as long as the glume. (Triodia avenacea 
HBK,)—Western Texas to central Mexico. Var. GRANDIFLORA (Vasey), of the same 
range, is slightly larger throughout, with spikelets 8 to 12 mm, long, and 6 to 8- 
flowered. (Triodia grandiflora Vasey.) 
++ ++ Floral glumes linear-oblong, lobes obtuse. 
4. S. Nealleyi (Vasey). Culms slender, 3 to5dm, high: panicle lance-oblong, 3 to 
6 em. long: spikelets 6 to 8 mm. long, 5 to 8-flowered; first empty glume nearly 
equaling and second slightly exceeding the lower florets; floral glume prominently 
pubescent; palet about one-half as long as the glume. (7Triodia Nealleyi Vasey.)— 
Cations, Presidio County, Texas. 
* * * Snikeleis oblong, subcompressed, in a rather dense spikelike panicle: culms leafy : 
leaves attenuate pointed, nervose. 
+ Panicle elongated: spikelets about 5 mm. long. 
== Lmply glumes much longer than the lower florets. 
5. S. stricta (Nutt.) Kuntze. Culms erect, 5 to 10 dm. high: leaves numerous 
2 to 5 dm. long: panicle rigid, 1 to 3 dm. long: spikelets 4 to 6 mm. lone, 2 to 
10-flowered ; floral glume obtuse or slightly emarginate, often mucronate, pubescent 
on the nerves below the middle, equaled by the palet.  (Tricuspis stricta Nutt.)—Low- 
land, central Texas to Louisiana. 
6. S. albescens (Munro) Kuntze. Culms 4 to 8 din. high, usually simple: leaves 
mnostly flat, 1 to 3 dm. Jong: panicle 1 to 2 din. long: spikelets short oblong, 4 to 6 
mm. long, 8 to 10-flowered; floral glumes rotund, somewhat emarginate or erose, 
mucronate, slightly pubescent at the base; palet broadly ovate, equaling the glume, 
(Tricuspis albescens Munro.)—Prairies, southern Texas to New Mexico. 
++ Panicle short, oblong: spikelets about 10 mm. long. 
7. S. congesta sp. nov. Culms 4 to & dm, high, from a perennial rootstock : nodes 
and throats of striate sheaths usually purple: leaves 5 to 15 cm. long: panicle 5 to 
8 cm. long; rays single, 1 to 3 cm. long, crowded with sessile spikelets: spikelets 8 
to 12 mm, long, 10 to 15-flowered, turgid; empty glumes slightly shorter than the 
adjacent florets, l-nerved; floral glume 4 to 5 mm. long, ovate-oblong, obtuse, 
mucronate, the lateral nerves slightly or not at all excurrent, pubescent on the 
