POACEAE 97 



62. Panicum lucidum AsHe. Stems tufted, 2-8 dm. long, slender, glabrous, weak, at 

 first erect or ascending, simple, later prostrate and much branched : leaves 3-5 ; sheaths 

 much shorter than the internodes, ciliate on the margin ; blades thin, glabrous, the primary 

 ones usually erect, 3-6 cm. long, 3-6 mm. wide, those on the branches much smaller, gen- 

 erally 3 cm. long or less and 1.5-3 mm. wide, spreading to erect : primary panicle ovoid, 

 3-7 cm. long, its branches spreading or somewhat ascending : spikelets glabrous, 1.5-2 

 mm. long and 0. 6-0. 75 mm. wide, elliptic. 



In wet shady places, usually sphagnum swamps, New Jersey and Maryland to Florida and Missis- 

 sippi. Summer and fall. 



63. Panicum curtivaginum Ashe. Stems tufted, 6-8 dm. long, slender, weak, gla- 

 brous, finally branched : leaves 4 or 5 ; sheaths much shorter than the internodes, some- 

 times sparingly ciliate on the margin ; blades erect, glabrous, the primary ones linear, 

 usually 3-6 cm. long, rarely larger, 3-5 mm. wide : panicle 4-8 cm. long, ovoid, its 

 branches ascending : spikelets 2 mm. long and about 1 mm. wide, elliptic, glabrous. 



In sandy soil, Mississippi. Spring and summer. 



64. Panicum curtifolium Nash. A nearlv glabrous tufted perennial. Stems 2-3 

 din. tall, finally much branched : leaves 3 or 4 ; sheaths usually about ^ as long as the in- 

 ternodes, sparsely pubescent with long weak spreading hairs ; blades widely spreading, 

 lanceolate, a few long hairs on the upper surface near the base, the primary blades 1.5-3 cm. 

 long, 3-5 mm. wide : panicle 2-4 cm. long, broadly ovoid, its branches widely spread- 

 ing : spikelets about 1.5 mm. long and about 0.75 mm. wide, elliptic, glabrous. 



In sandy soil, Mississippi. Spring and summer. 



65. Panicum sphagnicola Nash. Grayish green. Stems 6-10 dm. long, at first 

 simple, finally repeatedly and dichotomously branched, the branches very divergent : leaf- 

 blades glabrous, thick, lanceolate, the primary ones 5-8 cm. long, 4-10 mm. wide, those 

 on the branches 2.5 cm. long or less, 1-3 mm. wide, appressed : primary panicle about 5 

 cm. long, its branches spreading, 1.25-2.5 cm. long, the secondary panicles about 1.25 cm. 

 long, raceme-like : spikelets 2.5 mm. long and 1 mm. wide, few and appressed, glabrous 

 or sparingly pubescent. 



In sphagnum swamps, northern Florida. Summer. 



66. Panicum nudicaule Vasey. Glabrous. Stems 5-6 dm. tall : leaves 3, the lower 

 2 approximate and near the base of the stem, the other distant, above the middle of the 

 stem ; blades erect, firm, lanceolate, 2.5-7 cm. long, 3-8 mm. wide : panicle 4-7 cm. long, 

 broadly ovate, its branches ascending or spreading : spikelets 3 mm. long and 1 mm. wide, 

 elliptic, acute, glabrous. 



In swamps, western Florida. Spring and summer. 



67. Panicum Wrightianum Scribn. Stems tufted, 3-4 dm. long, puberulent, slen- 

 der, at first erect, finally much branched and forming broad mats : leaves 5-7 ; sheaths 

 minutely pubescent with spreading hairs, ciliate on the margins ; blades minutely and softly 

 pubescent on the lower surface, the upper surface pubescent with longer hairs, the primary 

 blades 2-4.5 cm. long, 2-4 mm. wide, those on the branches much smaller : primary panicle 

 3-5 cm. long, ovoid, its branches ascending : spikelets a little less than 1 mm. long and 

 about 0.4 mm. wide, elliptic, pubescent. 



In sandy soil, North Carolina to Florida and Mississippi. Also in Cuba. Summer and fall. 



68. Panicum B aldwinii Nutt. Glabrous or nearly so. Stems densely tufted, slender, 

 1-2 dm. tall, rarely longer, sometimes a little puberulent, erect, finally much branched and 

 ascending or prostrate : leaves on the primary stem 2, or sometimes 3 ; sheaths less than 

 as long as the internodes ; blades erect or ascending, lanceolate, rough on the margins, the 

 primary ones 1-3 cm. long, 1-3 mm. wide : primary panicle 1.5-4 cm. long, broadly 

 ovoid, its branches widely spreading : spikelets 1 mm. long and about 0.7 mm. broad, 

 oval, or somewhat broadly ovoid, glabrous. 



In dry sandy soil, southern Georgia and Florida, Spring and summer. 



69. Panicum ensifolium Baldw. A slender much tufted glabrous perennial. Stems 

 1-3 dm. tall, finally somewhat branched : leaves 2 or 3 ; sheaths very short, several times 

 shorter than the internodes ; blades widely spreading, lanceolate, usually less than 2 cm. 

 long, rarely larger, 1-3 mm. wide, densely puberulent on the lower surface, the basal blades 

 markedly larger and more erect : panicle small, ovate, 1-2 cm. long, occasionally larger, 

 its branches usually ascending : spikelets about 1.3 mm. long and about 0.6 mm. wide, 

 elliptic, pubescent with spreading hairs. [P. nitidum var. ensifolium ( Baldw. ) Chapm. ] 



In sphagnum bogs, North Carolina to Florida and Mississippi. Spring and summer. 



70. Panicum Cuthbertii Ashe. Stems tufted, slender, weak, 2-3 dm. tall, glabrous, 

 finally much branched : primary leaves 3 or 4 ; leaf-sheaths short, ciliate on the margin, 

 much shorter than the internodes ; blades densely pubescent beneath, more sparsely so 



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