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§2. Panicle of nearly sessile alternate spreading branches: spikelets sessile in twd rows on 
one side of a flattened rachis asin Paspalum, but with a small outer glume 3 perfect 
floret rugose.—BRACHIARIA. 
* Culms rather robust, though often weak and decumbent. 
4. P. paspaloides Pers. Culms 5 to 10 din, high, decumbent and rooting below, 
leafy : panicle 1 to 2 dm, long, strict, with 10 te 20 branches 4 em. long or less: spike- 
lets about 2 mm, long, smooth, subacute, plano-convex, in two regular rows with the 
backs of the floral glumes toward the rachis ; first glume broad, truncate, one-third 
as long as the floret ; second and third glumes equaling the floret.—In moist land, 
eastern Texas, Mexico, and southern Florida, 
5, P.platyphyllum Munro. Culms 5 to &§ din, high, usually decumbent, rooting 
and branching below: leaves smooth, lanceolate, subcordate at base: panicle of 3 
to 6 spreading, distant branches, 6 to 10 em. long, usually included at base: spike- 
lets ovate, acute, smooth, 3 to 4 mm. long ; first glume obtuse, one-third as long 
as the second and third; these acute, exceeding the floret.—Wet soil, eastern Texas. 
Nore.—P. cespitosum Swartz is found in Chihuahua and inay be expected in the 
bluffs and ravines between Del Rio and El Paso, It differs from the preceding in 
the shorter more numerous branches and shorter spikelets (barely 3 mm, long). 
**Culms very slender, creeping. 
6. P. prostratum Lam. Culms ascending,3 to 5 dm. high, from a long creeping 
base: leaves short, lance-ovate, subcordate and clasping: panicle 3 to & em. long; 
branches alternate, about 2 em. long: spikelets ovate, acute, smooth, nearly 2 mim, 
long; first glume one-fourth as long as the second and third; these acute, slightly 
exceeding the mucronulate floret.—Along streams and in wet soil, eastern Texas. 
§ 3. Spikelets densely crowded in 5 or 4 rows on one side of the rather slender flattened 
rachis of the alternate spikes: empty glumes scabrous or hirsute, acute or long- 
awned,—ECHINOCHLOA, 
7. P.colonum L. Culms 3 to6dm. high, usually decumbent at the base: leaves 
flat, glabrous: panicle 1 to 2 dm, long; branches erect or ascending, 2 to 3 em, long: 
spikelets 2 to 3 mm. long, acute; first outer glume nearly one-half as long as the 
second and third; these acute or acuminate and slightly exceeding the acute smooth 
floret.—Moist soil throughout the State. Var. ZONALE (P. zonale Guss), of southern 
Texas, is gencrally smaller and more spreading than the species, the leaves with 
transverse purple stripes. 
8. P. crus-galli L. (BARN Grass. Cock’s root.) Culms 5 to 15 dm. high, usually 
robust: leaves flat: panicle pyramidal, 1 to 8 dm, long, rather dense; branches 
ascending, 3 to 5 em. long below, shorter toward the apex: spikelets 4 to5 mm, long, 
often purple or nearly black; first glume broad, mucronate, one-third as long as the 
spikelet; second glume acuminate or awn-pointed, exceeding the acuminate floret; 
third glume equaling the second, terminating in an awn 5 to 20 mm. long.—Appar- 
ently native in the Southern States, Var, HIsripuM Torr. is large and coarse, with 
hispid sheaths and usually long awned spikes.—Moist rich land. Var. wuricum 
Vasey is generally smaller and with awnless spikelets.—Rather dry soil. 
§ 4. Spikelets white, silky hairy, sessile or short pediceled, in pairs on the simple erect 
branches of the panicle.—TRICHACHNE, 
* Lower glume very minute. 
9. P. lachnanthum Torr, (SiLKY PANIC-GRASs.) Culms erect, slender, 5 to 10 dm. 
high: panicle narrow, 1 to 1.5 dm. long, with short, erect branches: spikelets acu- 
minate, 3 to 4 mm, long; first empty glume smooth; second and third equaling or 
slightly exceeding the mucronate brown floret.—Dry plains, western Texas. 
NotE,—L, leucophaum HBK.,, although not reported from Texas, may be expected 
along the coast, It differs from the preceding in being more robust and having a 
larger, looser panicle. 
