POACEAE 73 



in pairs, 6-10 cm. long: spikelets in pairs, 2 mm. long and about 1.5 mm. wide, broadly 

 obovate, the first scale 3-nerved, the second one generally 2-nerved by the suppression of the 

 midnerve. 



In sand, Key West, Florida. Spring to fall. 



13. Paspalum elatum L. C. Rich. Stems 6-8 dm. tall : leaf-sheaths glabrous ; 

 blades 3 dm. long or less, 2-6 mm. wide, densely pubescent with long hairs above at the very 

 base, otherwise glabrous : racemes in 3's, 10-13 cm. long : spikelets on hispidulous pedicels, 

 elliptic, about 2.2 mm. long and 1.3 mm. wide, the 2 outer scales 3-nerved, the first scale 

 pubescent with long appressed hairs, the second one glabrous. 



In sandy soil, Key West, Florida. Also in tropical America. Spring to fall. 



14. Paspalum latifolium Le Conte. Stems tufted, 6-8 dm. tall : leaf-sheaths smooth 

 and glabrous, or the basal ones a little pubescent; blades 1.5-3 dm. long, or the upper- 

 most often shorter, 1-2 cm. wide, rather thin, lanceolate to linear-lanceolate, glabrous, or 

 some of them occasionally with a few scattered hairs on the margins near the base : racemes 

 on the main stem usually in pairs, rarely single, those on the branches single, 6-12 cm. 

 long : spikelets in pairs, on shorter puberulent pedicels, about 2 mm. long and 1.5-1.7 mm. 

 wide, broadly obovate, the first scale 3-nerved, pubescent with short spreading hairs, the 

 second scale 3-nerved, or rarely 5-nerved, glabrous. 



In dry usually shady places, Georgia and Florida. Spring and summer. 



15. Paspalum gracillimum Nash. Stems slender, 4-6 dm. tall : leaf-sheaths smooth 

 and glabrous : blades (the upper ones) 1.5 dm. long or less, 2-7 mm. wide, flat, a ring of 

 long hairs just above the ligule, otherwise glabrous : racemes 6-10, usually alternate, 

 widely spreading, slender, 3-7 cm. long : spikelets in pairs, obovate, 1.4 mm. long and 0.9 

 mm. wide, the 2 outer scales 3-nerved, the first scale pubescent with short glandular-tipped 

 hairs, the second scale glabrous, the third scale about $ as thick as broad. 



In sandy soil, Key West, Florida. Spring to fall. 



16. Paspalum pubescens Muhl. Stems tufted, 4-8 dm. tall, long-hirsute below the 

 racemes : leaf -sheaths glabrous, or sometimes pubescent on the margins or toward the apex, 

 the basal ones sometimes pubescent all over ; blades 4-23 cm. long, 3-6 mm. wide, rarely 

 broader, densely pubescent on both surfaces with long spreading rather stiff hairs arising 

 from papillae, if ciliate on the margins the hairs short : racemes usually 1, rarely 2 on the 

 main stem, generally straight, or sometimes a little curved, 6-12 cm. long, rarely shorter : 

 spikelets in pairs, glabrous, on shorter puberulent pedicels, about 2 mm. long and 1.5-1.8 

 mm. wide, broadly obovate, the 2 outer scales 3-nerved, or the second 2-nerved by the sup- 

 pression of the midnerve, the flowering scale triangular in cross-section, the angles rounded, 

 about two-thirds as thick as broad. 



In fields, New York and New Jersey to Pennsylvania, District of Columbia and Tennessee. Sum- 

 mer and fall. 



17. Paspalum Muhlenb6rgii Nash. Stems tufted, at first erect, finally reclining, 

 4-8 dm. tall, smooth and glabrous : leaf-sheaths generally pubescent all over with long 

 hairs or sometimes only on the margins ; blades 0.5-2 dm. long, rarely longer, usually 

 7-11 mm. wide, or sometimes narrower, ciliate on the margins with usually long hairs, 

 more or less pubescent on both surfaces with long hairs : racemes in 1's or 2's, straight or 

 curved, 5-10 cm. long : spikelets in pairs, glabrous, on shorter puberulent pedicels, about 

 2 mm. long and 1.8 mm. wide, oval or broadly obovate, the 2 outer scales 3-nerved, or the 

 second rarely 2-nerved by the suppression of the midnerve, the flowering scale triangular 

 in cross-section, the angles rounded, about as thick as broad. 



In fields or in sandy or stony ground, Massachusetts to Missouri and the Indian Territory, South 

 Carolina, Georgia and Mississippi. Late summer and fall. 



18. Paspalum setaceum Michx. Stems tufted, slender, 2-7 dm. tall : basal leaf- 

 sheaths densely pubescent with long hairs, the upper ones only on the margins ; blades 

 3-14 cm. long, rarely somewhat longer, usually 2.5-5 mm. wide, sometimes a little 

 broader, linear, strict and erect or ascending, densely pubescent on both surfaces with long 

 hairs : racemes single, slender, 4-8 cm. long, sometimes a little longer : spikelets either 

 single or in pairs, on shorter puberulent pedicels, about 1.5 mm. long and about 1.3 mm. 

 wide, broadly obovate, the first scale 3-nerved, pubescent with spreading glandular-tipped 

 hairs, the second scale 2-nerved, the midnerve rarely, if ever, present, glabrous or occasion- 

 ally pubescent. 



In dry sandy soil, southeastern New York to Florida, west to Mississippi. Summer and fall. 



19. Paspalum villosissimum Nash. Plant yellowish gray-green. Stems tufted, 

 erect, 4-10 dm. tall : leaf-sheaths crowded at the base of the stem, very densely pubescent, 

 as well as both surfaces of the blades, with very long white spreading hairs ; blades erect 

 or ascending, thick, lanceolate, 2 dm. long or less, 6-10 mm. broad : racemes single or in 



