98 POACEAE 



above, witli ratlier long hairs, tlie primary ones spreading, 1-3 cm. 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, jjubescent. 



In wet places, South Carolina to Florida. Spring and summer. 



71. Panicvim gracilicaule Nash. Glabrous. Stems tufted, erect, slender, 1-3 dm. 

 tall : leases 3 or 4 ; sheaths shorter than the blades ; blades erect, linear, acuminate, 3-7 

 cm. long, 3-8 mm. wide : panicle 3-6 cm. long, ovoid, its branches ascending : sijikelet.s 

 about 1.1 mm. long and 0.7 mm. wide, obovoid, pubescent with spreading liaii's. 



In sandy soil along brooks, Sand Mountain, .\labama. Summer. 



72. Panicum flavoviieas Nash. A glabrous tufted light green perennial. Stems 

 2-3 dm. tall, slender, linally 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 ram. wide, usually minutely pnljcscent 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 J as long as the 

 spikelet. 



In swampy woods, Florida. Summer. 



73. Panicum alboniargiaatum Xash. 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 cm. long, rarely longer, 2-7 mm. wide : panicle 2-4 cm. long, broadly ovate : spike- 

 lets elliptic, about 1.3 nmi. long and 0.7 mm. wide, pubescent with short spreading hairs. 



In low pine lands, peninsular Florida. Spring and summer. 



74. Panicum trifolium Nash. A nearly glabrous tufted perennial. Stems slender, 

 2-4 dm. tall, finally a little branclied : 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 glabrissimum Ashe. Stems tufted, rather slendir, 3-4 dm. tall, finally 

 somewhat liranched : leaves about 3, distant ; sheaths less than i as long at. 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 longiligulatum 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 or 5 ; sheaths minutely pubescent between the prominent 

 nerves ; ligule of erect silky hairs about 3 mm. long ; blades ascending, lanceolate, ob- 

 scurely 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 paucipilum 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 0-9 cm. long, 5-7 mm. wide : panicle 5-10 cm. long, rather 

 dense, its branches erect-a.scending or erect: spikelets nnmerou.s, about 1.4 mm. long and 

 0.8 mm. wide, oval, pubescent with spreading hairs, the first scale about I as long as the 

 spikelet. 



In wet soil, southern New Jersey to Florida and Mississippi. Summer. 



78. Panicum octonodum 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 

 cm. long, 4-S mm. wide, lanceolate : panicle 9-13 cm. long, oblong, dense, 2-4 cm. wide, 

 its branches erect or erect -ascending : spikelets 1.3 mm. long and al^out 0.8 nnn. wide, 

 oval, glabrous. 



lu wet places. New .Jersey to Alabama and Texas. Spring and summer. 



