POACEAE 59 
19. dum (Bertol) Nash. Stem erect, 70-130 cm. tall: leaf-sheaths 
Bun bene ecu eras pue mm. wide, glabrous beneath, hirsute above 
toward the base: ra S 2-5, 7-15 em. long, erect; the rachis very slender, 
flexuous: spikelets rd id 8. 5—4 mm. lon T: racemulosum Nutt.]—Dry pine- 
3 
ng. 
lands, sandy woods, shaded Du and thiekets, Coastal Plain, Fla. to Tex. 
and S. C. 
laeve Mie Stem erect or ascending, glabrous, em m em. tall: leaf- 
blades glabrous, o or P ad pilose on the upper surface: racemes 2-5, usually 
or 4, 3—10 em. po spreading or ascending: spikelets 2. 53 mm. long. [P. 
angustifolium L e P. australe N ru s ood. swamps, and mea- 
dows, various nc. Fla. to Tex. and N. J. 
21. P. longipilum Nash. Resembling P. laeve: Pee pilose on both su 
faces or nearly ds beneath: racemes 2-6, lax and spr num 
[P. ud Nash pra viria iud Nash] Mat ps soil, pinelands, 
, and N. Y. 
22. P. circulare Na sh. Stem 30- A cm. be leaf- — sparsely pilose or 
the upper S blades 5-10 mm. wide, usually more or less pilose: racemes 
—4, 5-10 em. long, m mostly suberect or the lower irae ing.—Fields, marshes, 
meadows, prairies, and sandy Md Coastal Plain and occasionally adj. prov- 
inces, N. C. to Tex., Kans, and Con 
23. P. praecox Walt. Stem 50- RA cm. tall, P og scaly rootstocks: 
leaf-sheaths glabrous or the lower pilose; blades 3-7 vide , Bla abrous, or 
T pilose on upper s n. toward the base: raceme ios 8 (us ually 4-6), 
2-7 em. long, ascending.—Wet uiis e marshes, and pude odi Plain, 
Fla. to Tex. an d N. C. 
24. P. lentiferum Lam.  Resembling P. praecox, but co pups d more robust, 
the leaf-sheaths and blades s eonspieuously pilose: os s 2-9, usually 
4 or 5, 38-10 em. long. [P. Curtisianum Steud. P. glaber n P. tardum 
Nash P. Kearneyi Nash P. amplum Nash] Moist M cde wet woods, and 
marshes, Coastal Plain, Fla. to Tex. and N. C. 
25. P. difforme LeConte. Stem 35—75 em. tall: leaf-sheaths pilose on keel 
e margin or glabrous; blades d pilose on the upper surface at piel 
t base: racemes 2 or 3, 3.5-8 em. long: spikelets mostly in p 3.04 m 
n oval.—Low grounds and rich woods, Coastal Plain, Fla. to La., and Ga, 
26. P. giganteum Baldw. Stem ae pies ins 200 em. oe a E 
scaly rootstocks: leaf-sheaths glabrous or pi : racemes ually 3 E: 
10-20 em. long: spikelets 3—3.8 mm ee val or oc te, Ebo. [Pid 
cilium Nash.|—Moist ud soil or clay, pinelands, marshes, and ditches, 
Coastal Plain, Fla. to Mis 
27. P. floridanum Michx. Stem 100—150 em. tall, iid E aie E 
(more robust and taller: foliage glabrous or near raging 
wm. . altissi 
me : Sp 
0 val, glabrous.—Low sand soil, pinelands, prairies 
swamps, and fields, Constel Plain ae rarely a. provinees, Fla. to , Mo., 
and Va. 
28. P. lividum Trin. Stem 60-100 em. tall: leaf-sheaths usually glabrous; 
blades 3-6 mm. wide, sometimes pubescent on the upper surface: racemes 
