392 ORDER 155. GRAMINE.E. 



x Abortive fl. usually staminate. Spikelets obovate, H" Nos. 19, *) 



x Abortive flower neutral, never with stamens. . . (y) 



y Plant stout, soft-downy, except the smooth noder No. 21 



y Plant smoothish, or rough-Miry, branched or simple Nos. 22, 2S 



Exotic, cultivated.... No. 24 



1 P. capillare L. Culms thick at base, 1 2f ; Ivs. broad-linear, and with the sheaths 



bristly-hairy; panicle ample, pyramidal, capillary, loose; spkl. lance-ovate, acumi- 

 nate, |", purple. @ Fields and wayside?. Aug. 



2 P. autumnale Bosc. Culm slender, 1020' ; Ivs. short, soon rolled, and with the 



long sheaths glabrous ; pan. diffuse, bearded in the axils ; ped. long (2 4'), capillary ; 

 spkl. lance-oblong; lower gl.- minute. 111. to Car. 



3 P. proliferum Lam. Glabrous, 2 3f; Ivs. broad-linear, en tumid sheaths ; pan. 



terminal and lateral, pyramidal, ped. sheathed ; spkl. elliptic, 1"; lower gl. 1 / 4 or 

 Vs as long as the upper ; e fl. pointed. Rich shady soils. Aug., Sept. 

 /3. sTftiicnlntunit Culm thick, geniculate below ; pan. dense. Marshes. 



4 P. gymnocarpum Ell. Culms 2 3f, stout, erect ; Ivs. lanceolate, 1' wide ; pan. 



large, expanding ; spkl. lanceolate, 2", m clusters of 35 ; glumes and neutral pales 

 twice longer than the naked fertile fl. Bank?, Ga., Fla., and W. 



o P. liians Ell. Slender, glabrous, decumbent at base, 2f; Ivs. narrow; pan. of slen- 

 der racemes; spkl. f-", lower gl. $ | as long as the upper; both fls. coriaceous, di- 

 vergent or gaping at apex. Damp barrens, S. Aug. Oct. 



6 Po agrostoides Muhl. (a) Culm 1 J 3f, compressed ; Ivs. long, rough-edged ; 



pan. term, and lateral, pyramidal, purplish, of dense racemes ; spkl. (6) 1", lance 

 ovate; upper gl. 3-veined, $ longer than the lower; neutral pales sub-equal. Jl. ^ 



7 P. anceps MX. Culm and Ivs. as in No. 6. Pan. very large and open; spkl. 1J", 



forked when ripe ; upper gl. 5-veined. twice longer than the lower, shorter than tho 

 lower neutral pale, which is twice longer than the other pales. N. J., and S. Aug. + 



8 P. vilfiforme Wood. Very glabrous ; pan. at each joint, and term, of loose ra- 



cemes ; spkl. lance-ovate ; up. gl. 9-veined, 1^", lower neutral pale a little longer, the 

 other 3 pales a little shorter, lower gl. as long. Meadows, E. Tenn. Aug. 



9 P. gibbum Ell. Culm 2 3f, assurgent; Ivs. broad-linear, glabrous; pan. 56', 



dense, spindle-form ; spkl. tumid, near 2" ; lower gl. very small, upper very large, 

 11-veiued, gibbous at base; sterile fl. (<j, Chapm.) neutral. Wet. S. Jl. Sept. 



10 P. amarum Ell. Culm terete, strict, 2 3f; Ivs. rolled and rigid (bitter to taste) , 

 pan. 6 1(K, contracted, its smooth branches appret-sed-erect ; spkl. lance-ovate ; 

 glumes pointed, the lower 1", upper nearly 2"; sterile fl. H", anth. orange. Sands. 



IIP. virgatum L. Culm 3 5f, Ivs. flat; pan. large, thin, at length diffuse, 1020' 

 long; spkl. scattered, ovate, pointed, purplish; upper gl. 2", sterile fl. 1^", fertile fl. 

 and lower gl. 1", all divergent when ripe ; anth. purple. N. Y., S., and W. Aug. 

 /3. obi nun tii. Panicle contracted ; spikelets smaller, not pointed, obtusish. N. J. 



12 P. verrucosum Muhl. Slender, weak, decumbent below, 10 20'; Ivs. lance- 

 linear, short ; pan. few-flowered ; spikelets obovate, bluish, \ $", beset with fine 

 warty (cerrucous) points. <T) Thickets and swamps, not rare. Aug. 



13 P. vlllosum Ell. Villous with soft white hairs throughout, 10-20'; Ivs. flat, 

 short ; pan. small (2 3' long), oblong, loose ; spkl. oval, 1", green ; upper gl. and 2 

 fls. equal, lower glume J- as lon^. Evjr^ejn, di n;>. S. Apr., Ma/. 



14 P. eillatlflorum Wood. Fringed G. Erect, strict, 2 3f; Ivs. narrow, rigid, 

 flat, ciliate; pan. slender, strict, 34'; spkl. H", oblong, silky-villous glume soli- 

 taiy, equaling the lower staminate pale, 5-veined. Barrens, S. Sept. 



0. rvfunit Lvs. glabrous, erect ; sterile fl. neutral, hairs purple. 



15 P. dirhctomum L. Culm at first simple with one panicle, soon branched, 

 slender, 820'; Ivs. lance-linear, short, 14' by 24"; terminal pan. oval, small 

 (12'), stalked ; spkl. few and small, J", round-oval ; lower gl. J i as long as the up- 

 per. Common in fields. June Sept. 



