98 POACEAE 
above, with rather long hairs, the primary ones spreading, 1-3 em. long, 1.5-3 mm. wide: 
panicle 1.5-3 cm. long, ovate, its branches spreading: spikelets elliptic, about 1.3 mm. 
long and 0.5 mm. wide, pubescent. 
In wet places, South Carolina to Florida. Spring and summer. 
71. Panicum gracilicaüle Nash. Glabrous. Stems tufted, erect, slender, 1-3 dm. 
tall: leaves 3 or 4; sheaths shorter than the blades; blades erect, linear, acuminate, 3-7 
em. long, 3-8 mm. wide: panicle 3-6 cm. long, ovoid, its branches ascending: spikelets 
about 1.1 mm. long and 0.7 mm. wide, obovoid, pubescent with spreading hairs. 
In sandy soil along brooks, Sand Mountain, Alabama. Summer. 
72. Panicum flavóvirens Nash. A glabrous tufted light green perennial. Stems 
2-3 dm. tall, slender, finally much branched : leaves 2 or 3; sheaths very short, the lower 
ones ciliate on the margin, the exterior basal ones pubescent all over ; blades thin, erect, 
smooth or nearly so on the margins, linear-lanceolate, the primary ones 2.5-4 cm. long, 2.5 
-4 mm. wide, usually minutely pubescent on the lower surface between the nerves: panicle 
3-4 cm. long, broadly ovate, its branches spreading : spikelets 1.5 mm. long and 0.7 mm. 
wide, elliptic, densely pubescent with spreading hairs, the first scale about + as long as the 
spikelet. 
Inswampy woods, Florida. Summer. 
73. Panicum albomarginàtum Nash. Glabrous, excepting the spikelets. Stems 
densely tufted, 2-4 dm. tall, finally branched toward the base, the upper part of the stem 
naked : leaves usually 2 ; sheaths on the primary stems much shorter than the internodes ; 
blades erect, thick, stiff, lanceolate, with a prominent wide thickened white margin, usually 
1.5-4 em. long, rarely longer, 2-7 mm. wide: panicle 2-4 cm. long, broadly ovate : spike- 
lets elliptic, about 1.3 mm. long and 0.7 mm. wide, pubescent with short spreading hairs. 
In low pinelands, peninsular Florida. Spring and summer. 
74. Panicum trifolium Nash. A nearly glabrous tufted perennial. Stems slender, 
2-4 dm. tall, finally a little branched : leaves 3, rarely 4, the uppermost one much above 
the middle of the stem and generally but a little below the panicle ; sheaths often but | 
as long as the internodes; blades erect or nearly so, firm, lanceolate, the margins thick- 
ened and cartilaginous, 1.5-6 cm. long, 1.5-5 mm. wide: panicle 2.5-6 cm. long, broadly 
ovoid, its branches ascending : spikelets 1.5 mm. long and about 0.7 mm. wide, ellipsoid, 
densely pubescent with short spreading hairs. 
In sandy soil, North Carolina to northern Florida and Mississippi. Spring and summer. 
75. Panicum glabríssimum Ashe. Stems tufted, rather slender, 3-4 dm. tall, finally 
somewhat branched : leaves about 3, distant ; sheaths less than å as long as the internodes ; 
blades erect or ascending, pubescent on the lower surface with short hairs, 1.5-3 5 cm. 
long, 2-3 mm. wide: panicle long-exserted, 3-5 cm. long, ovate, its branches ascending : 
spikelets 1.5 mm. long and a little less than 1 mm. wide, oval, pubescent with spreading 
hairs. 
In dry soil, North Carolina. Summer. 
76. Panicum longiligulàtum Nash. A tufted nearly glabrous perennial. Stems 4-5 
dm. tall, slender, finally branched, the branches fasciculately much divided and forming 
dense masses at their ends : leaves 4 or5 ; sheaths minutely pubescent between the prominent 
nerves; ligule of erect silky hairs about 3 mm. long ; blades ascending, lanceolate, ob- 
securely and minutely pubescent on the lower surface, the primary ones 2.5-3 cm. long, 
about 3 mm. wide: panicle 5-6 cm. long, oval, its branches spreading : spikelets about 1.3 
mm. long and 0.8 mm. wide, oval, densely pubescent with spreading hairs. 
In dry sandy soil, western Florida. Summer. 
77. Panicum paucípilum Nash. A tufted nearly glabrous perennial. Stems 6-10 
dm. tall, finally somewhat branched : leaves 5-8 ; sheaths with the exterior margin ciliate 
toward the summit ; blades erect or ascending, thickish, rather firm, sometimes minutely 
puberulent on the lower surface, usually with a few hair-bearing papillae at the base, the 
lower and larger primary ones 6-9 cm. long, 5-7 mm. wide: panicle 5-10 em. long, rather 
dense, its branches erect-ascending or erect: spikelets numerous, about 1.4 mm. long and 
0.8 mm. wide, oval, pubescent with spreading hairs, the first scale about 4 as long as the 
spikelet. 
In wet soil, southern New Jersey to Florida and Mississippi. Summer. 
78. Panicum octonódum J. G. Smith. Glabrous. Stems erect, 7-11 dm. tall, finally 
branched : leaves 6-8 ; sheaths much shorter than the internodes ; blades erect, firm, 4-11 
em. long, 4-8 mm. wide, lanceolate: panicle 9-13 cm. long, oblong, dense, 2-4 em. wide, 
its branches erect or erect-ascending: spikelets 1.3 mm. long and about 0.8 mm. wide, 
oval, glabrous. 
In wet places, New Jersey to Alabama and Texas. Spring and summer. 
