892 ORDER 155. GRAMINE^E. 



x Abortive fl. usually etaminate. Spikelets obovate, 1|" NOB. 19, 90 



a? Abortive flower neutral, never with stamens. ..(y) 



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



y Plant smoothish, or rough-hairy, branched or simple Nos. 22, 25 



Exotic, cultivated.... No. 24 



1 P. caplllare 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. (D Fields and waysides. Aug. 



21 P. an tiiimiale Bosc. Culm slender, 10 20' ; Ivs. short, soon rolled, and with the 

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

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



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



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

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

 /3. g-enicnlhtnm. Culm thick, geniculate below ; pan. dense. Marshes. 



4 P. gymnocarpum Ell. Culms 231', stout, erect ; Ivs. lanceolate, 1' wide ; pan. 



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

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



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



der racemes; spkl. f", lower gl. $ i 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$ 3f, compressed ; Ivs. long, rough-edged ; 



pan. term, and lateral, pyramidal, purplish, of dense racemes; spkl. (ft) 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. 0. Pan. very large and open; spkl. H", 



forked when ripe ; upper gl. 5-veiued. 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, H", 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-veined, gibbous at base; sterile fl. (<$ , Cliapm.) neutral. Wet. S. Jl. Sept. 



10 P. am a rum EH. Culm terete, strict, 2 3f; Ivs. rolled and rigid (fritter to taste) , 

 pan. 6 1CK, contracted, its smooth branches appressed-erect ; spkl. lance-ovate; 

 glumes pointed, the lower 1", upper nearly 2"; sterile fl. 1$", 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. !$", fertile fl. 

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

 ft. ohlltnutut Panicle contracted ; spikelets smaller, not pointed, obtusish. N. J. 



12 P. verrucosum Muhl. Slender, weak, decumbent below, 1020'; Ivs. lance- 

 linear, short ; pan. few-flowered; spikelets obovate, bluish, 5- J", beset with fine 

 warty (i'erritcou,i) points. (T) Thickets and swamps, not rare. Aug. 



13 P. villosum Ell. Yillous with soft white hairs throughout, 1020'; Ivs. flat, 

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

 11s. equal, lower ghintie i-a^ long. Evjr^-cjn, (Un;>. S. Apr., Ma/. 



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

 flat, ciliate; pan. slender, strict, 3 4'; spkl. 1J", oblong, silky-villous glume soli- 

 tat y, equaling the lower sttiminate pale, 5-veined. Barrens, S. Sept. 



/3. ritfum, Lvs. glabrous, erect; sterile 1 fl. neutral, hairs purple. 



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

 slender, S 20' ; Ivs. lance-linear, short, 14' by 24"; terminal pan. oval, small 

 (1 2'), stalked ; spkl. few and small, I", round-oval ; lower gl. i $ as long au the up- 

 per. Common in fields. June Sept. 



