Oedeb 156.— GRAMINB^. 797 



base, compressed, 3 to 8' ; Ivs. lance-linear, short, smooth, carinate, on loose, 

 glabrous sheaths ; stip. oblong, dentate ; panicle spreading, the branches gener- 

 ally solitary, at length horizontal ; spikelets ovate-oblong, rather numerous, con- 

 taining about 5, loose flowers. — <I) A small, abundant, annual grass, Can. and 

 tJ. S., forming a dense, soft and beautiful turf. May — Sept. 



2 P. flexuosa Muhl. Culm erect from a tufted base, 12 to 20' ; Ivs. 2 to 5' by 1^ 

 to 2^'', gradually acute ; upper half of the culm naked, bearing a thin, open pan. ; 

 branches mostly in pau-s, filifbrm, often flexuous, long (2 to 3'), with the few 

 pedicellate spikelets at the end ; fls. 3 or 4, lanceolate, soarious-pointed, pubes- 

 cent but not webbed at base, the gls. about as long (2J"). — y "Woods, Va., 

 Ky. to Ga. Spikelets not purplish. Apr. — Jl. (P. autumnahs Muhl.) 



B. sCARioSA. Fls. of the spikelet 4 to 6, narrowly lanceolate, remote, nearly 

 glabrous, with conspicuously scarious (blunt) points. — E. Tenn. 



3 P. hezdntha. Culm weak and slender, 18 to 24', erect from the decumbent 

 lower joint ; Ivs. 3 to 5' long, very gradually attenuated, the upper reaching the 

 panicle which is very open, the branches in pairs, long (2 to 4'), bearing the long- 

 pediceled spikelets hear the end; spikelets oblong (4"), mostly 6 (5 to 1)-floviered, 

 fls. remote, oblong, villous (not webbed) at base, very obtuse and compressed at 

 the scarious apex. — 1( Pound at Atlanta, Ga., in meadows, perhaps a foreigner. 

 Spikelets -few but large. Jn. 



4 P. din^ntha. Culms in dense tufts, very slender, 18' to 2fl fi'ora fibrous roots i 

 Ivs. narrowly linear, about 3' by 1", soon reflexed, sheaths rather shorter ; ligule 

 short, truncate f pan. very slender and few-flowered, branches erect, very few, 

 solitary or 2 together ; spikelets 2 or 3 (mostly 2)-flowered ; fls. acute, obscurely 

 veined, smooth, except the copious web at base, the acute glumes much shorter. 

 — Fields, Montgomery, Ala. May, Jn. 



5 P. brevifolia Muhl. Culm compressed, 1 to 2f; Ivs. of the culm about 2, flat, 

 oblong, cuspidate and pungent, lower about 1' long, upper 6", root Ivs. long and 

 narrow, all erect, keeled and pungent at the point; ligule truncate, lacerate; 

 sheaths nearly as long as the nodes ; pan. loose, branches filiform, in pairs ; spike- 

 lets ovate, 3 to 4-flowered ; fls. rather obtuse, 2 j" long, slightly webbed. 1[ Penn. 

 (Jackson) to Va. and 111. Spikelets often tinged with purple. Apr., May. (P. 

 pungens Nutt. P. cuspidata Bart.) 



6 P. debilis Torr. Culm erect 18' to 2f; Ivs. lance-linear, flat, gradually acute; 

 ligule oblong, acute; pan. loose, few-flowered, some spreading, branches mostly in 

 pairs, flexuous; spikelets ovate, obtuse; 3 (rarely 2)-flowered; fls. very obtuse, 

 IJ" long, faintly 3-veined, webbed at base ; palea green; glumes ovate, acute. — 

 Eocky woods; Conn, to 111. 



7 P. laza Hcenke. Culm c«spitous, 6 — 8'; Ivs. linear, acute, erect; stip. lanceo- 

 late; pan. 1 — 2' long, contracted, nodding, branches mostly in pairs, smooth, 

 flexuous; spikelets 2 J" long, ovate, 3-fiowered; fls. often purple, acute, hairy, 

 somewhat webbed at base; glume lance-ovate, slightly scabrous on the keel; 

 lower palea hairy below, upper rough-edged ; auth. violet. — 2f Mountains if. Eng. 

 and N. T. to Arc. Am. 



8 P. alpina L. Culnns erect, 6', from fibrous roots; Ivs. short, broadly linear, 

 obtuse, lower with short, truncate ligules, upper with oblong, acute ones; pan. 

 equal-sided, erect, ovate or oblong, loose, the branches in pairs, spreading, with 

 rather large, ovate, short-pediceled, 5 (4 to 9)-flowered spikelets; fls. ovate. — 

 Can. West and high northward. Jn. 



9 P. compressa. Blue Grass. Ouim decumbent and rooting at base, much com- 

 pressed, 12 — 18'; Ivs. linear, short, bluish green; sheaths rather loose, with a 

 short, obtuse stipule ; pan. contracted, 3' by 1' or less, somewhat secund, branches 

 very short, in 2s and 3s ; spikelets ovate-oblong, flat, 3 to 7-flowered, subsessile, 

 fls. rather obtuse, webbed. A valuable grass, with sweet and nutritious herbage, 

 propagating itself everywhere (Ta., Tenn., northward) in woods, pastures and 

 meadows. May, Jn. (a month later than P. pratensis). 



10 P. sylv^Btris Gray. Culm erect, compressed, 2 to 3f; Ivs. flat, soft, 3 to 6' 

 long, 1 to 2" wide, gradually attenuated; ligules blunt; pan. oblong-pyramidal, 

 thin, branches' in 5s or more,, flexuous, 1 to 2' long; spikelets (2") pedicellate, 

 broad-ovate, 2 or 3-flowered ; fls. oblong, obtuse, copiously webbed. — Booky woods, 



