Oedbe 156.— GRAMINE^. 785 



spHcekis obimg-lanceolaie, acute, glabrous; glumes veiny, very unequal, the lower 

 minute. — Sand hills, Mason Co., 111. (Mead, iu Gray's Manual). 



3 P. proliferuni Lam. Culm assurgeut, geniculate at base, very smooth, thick 

 and succulent; Ivs. linear-lanceolate, 4 to 6" wide, 10 to 15' long, on tumid 

 sheaths, hairy at tliroat ; pan. large, pyramidal, terminal and axillary, smooth ; 

 spikelets oblong, acute, veiny, 1" long, densely racemed ; lower glume J as long 

 as the upper ; abortivo fl., with 1 pale. — (£) Marshes, especially brackish and 

 sandy, Mass. to La., also along the Western rivers. Aug., Sept. (P. genieulatum 

 Muhl.) 



4 P. gibbum Ell. Culm terete, assurgent, 2 to 3f, with black joints ; Ivs. lance- 

 linear, glabrous, 4 to 8' by 4 to 8'', on smooth, strongly striate sheaths; pan. 

 densely contracted, often purple, fusiform, about C long, strict ; spikelets near 2" 

 long, obtusish, lower glume very small, upper very large, 11-veined, remarkably 

 gibbous at base, upper pale nearly as long as the lower.— (J) "Wet soils, S. States. 

 Jl.— Sept. (P. EUiottianum Sohl.) 



5 P. hians Ell. Culm very slender, almost filiform, decumbent and rooting at 

 the lower joints, about 2f high; Ivs. narrowly linear, 8 to IS' long, glabrous; 

 sheaths hairy only at the throat; panicle pyramidal, spikelets racemed, i" long; 

 lower glume half as long as the upper, neutral pales ec[ual, conspicuous {gaping), 

 a little longer than the fertile. — ^Damp pine barrens, S. States, common. Aug.— 

 Oct. (P. debile Poir. P. divarioatura Mx.) 



6 P. agrostoides Muhl. Culm compressed, glabrous, 1^ — 3f high, often genicu- 

 late at bass ; Ivs. long and numerous, cauline lineat-lanoeolate, cariuate, rough- 

 edged, on short, striate sheaths; panicles terminal and lateral, pyramidal, com- 

 posed of racemed, spreading or deflexed branches; spikelets 1" long, purple, lance- 

 ovate, acute, crowded ; upper gl/ume 3-veined, ^ longer than the lower ; upper neu- 

 tral, pale, nea/rly as long as the lower. — U Meadows, frequent. July. (P. fusco- 

 rubens Nutt.) 



7 P. ^nceps Mx. Culm compressed, 2 to 3f; Ivs. linear, carinate, very long, 

 rough-edged ; sheaths anoipital, pilous on the throat and margin ; pan. erect, 

 pyramidal, with subremote, subsimple, interruptedly racemous branches ; spikelets 

 l-i"" long, lanceolate, very acuminate, and when mature, forked ; lowe/r glume and 

 upper pale half as long as the lower pale, scarcely shorter than the fertile flower ; up- 

 per glume 1-veined. — Wet soils, N. J. and S. States. Aug. — Nov. 



8 P. vilfiforme. Glabrous throughout; culm decumbent, ascending 2 to 3^ 

 branched ; Ivs. long, linear, scarcely rough-edged ; sheaths with a tuft of hairs at 

 throat ; pan. simple, with racemed, spreading branches ; spikelets 2" long, lan- 

 ceolate, acute ; lower glume \ to^ as long as the upper, 1-veined glume which is 

 shorter than the lower pale (while in Nos. 6 and 7 it is longer than the lower 

 pale 1). — Wet meadows, E. Tenn. 1 Jl., Aug. 



9 P. amarum Ell. Glabrous, leafy ; culm 2 to Sf high, stout ; Ivs. glaucous, cor- 

 iaceous, rigid, linear, 10 to 18' long, margins involute, not scabrous; sheath some 

 shorter than the joints ; pan. large, contracted, its very smooth branches appressed ; 

 spikelets thick, 2" long, ovate, acuminate, lower glume nearly as long as the 

 sterile pales, which contain 3 orange-colored stamens. — 2^ Sandy shores, Conn, 

 to Fla. and La. (Hale). Lvs. excessively bitter (BUiott). Aug. — Oct. 



10 P. virg^tum L. Glabrous and often purple ; culm 3 — Sfhigh; te. flat, long, 

 linear-lanceolate, hairy at base ; sheaths striate ; slip, with long, white cilis ; 

 pan. pyramidal, loose, spreading, diffuse, very large ; fls. acuminate, the glumes 

 2-^" long, very pointed, divaricate, the lower f as long as the upper ; pales of the 

 abortive flower nearly equal, enfolding the purple stam,ens. — If Salt-lick prairies, 

 fields, &c., N. Y. to Ind., S. to the Gulf. Aug. 



11 P. verruocsum Muhl. Culm slender, decumbent and geniculate, blanching 

 from the base, 1 — 2f high ; lvs. lanoe-hnear, flat, 4 to 6' by 2 to 4", spreading, 

 smooth ; pan. much expanded, few-flowered ; spikelets J to J" long, covered with 

 wa/rty points {verrucous) obovate, bluish ; abortivo flower of one palea, and neuter. — 

 (p? Swamps and thickets. Mid. and S. States. Panicles terminal aud lateral, loose 

 and capillary. Aug. (P. debilis Ell. nee Poir. P. ramnlosum Mx.) 



12 P. frdgile Kunlh. Gubm geniculate at base, assurgent, branched, very brittle, 



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