Oeder 156.— GKAMINB^. 78T 



1 J" long, green ; lower glumo ovate, not half as long as the upper ; abortive 

 pales subequal, usually with 3 stamens. — In moist, shady places, If. S. and Can. 

 Jn., JI. (P. seoparium and nervosum Lam. P. eiliatiuu Ell., etc.) 



20 P. xanthoph^sum Gray, Culm generally simple, glabrous, 9 to 15' high ; 

 Iva. lanceolate, 3 to 6' by 5 to 1", not dilated at the ciliate, clasping lose, smooth, 

 9 to 1 l-veined ; pan. long-exserted, simple, raceme-like, few-flowered ; spkl. round- 

 ish-obovate 1 V long ; lower glume ovate, 3- veined; aoutish, J as long as the up- 

 per many-veined one ; abortive pales oftener with 3 stamens. — Dry soils, N. Eng. 

 to Wis. (Lapham). Rare. Jn.' 



21 P. visoiduni Ell. Hoary, with a dense, short, soft, viscid pubescence ; culm 

 decumbent, assurgent 2 to 4f, stout; joints a smooth brown ring; Ivs. lance- 

 linear, 3 to 6' by 6 to 16'' ; sheaths much shorter than the internodes; pan. rather 

 large (4 to 6' long); loose ; spkl. light green, 1" long, oval, acutish, lower glume 

 very small, upper pale very small, truncate. — y Damp places, IT. J. to Ga. (Feay). 



22 P. claudestinum L. Culm with short, axillary, appressed branches, 2 to 3f 

 high, rigid, leafy ; Ivs. 3 to 6' by 1', lanceolate, subcordate at base ; sheaths his- 

 pid with papilJaj in the grooves bearing bristly hairs, and enclosing the short 

 lateral panicles ; spkl. elliptical, acutish, 1^" long, striate, often purple ; upper 

 pale of the neutral fl. obtuse. — if Hoist woods, Mass. and Mid. States. JL, Aug. 



23 P. mioroo^rpon Muhl, Darl. Culm 18 to 30' high, erect, simple, glabrous; 

 joints glabrous ; Ivs. lanceolate, veined, ciliate at base, undulate and scabrous on 

 the margin, scabrous above, smooth beneath, C to 10" wide; sheaths deeply 

 striate, smooth ; stip. ; pan. rnvdi branched, nearly smooth ; spkl. small, (^" 

 long), roundish-obovate, .purple, numerous, scarcely putescent ; upper sterile pale 

 minute; fr. shining, bluish white. — y. 



24 P. "Wdlteri Ell. Culm slender, glabrous, erect, 2f ; Ivs. linear 3 to C by 2 to 

 3", glabrous as well as the open sheaths ; spikes thick, dense, 1-sided, alternate 

 (the 2 lower sometimes opposite), 6 to 12" long ; spkl. imbricated in 3 rows, 

 broad-ovate ; glumes minutely hispid, the lower half as large, upper 3-veiued ; 

 abortive pales unequal, staminato ; fertile fl. roundish. — Damp grounds. Can. to 



~ Fla. and La. Jn. — Aug. (Nearly allied to OpUsmenus.) 



25 P. Aurelianum Hale (MS.). Culm decumbent, geniculate, slender, branched, 

 glabrous ; Ivs. lanceolate, glabrous, 1 to 2' by 3 to 4", sheaths cUiate ; spikes 

 slender, 6 to 12" long, alternate, 1 -sided; spkl. ovate, acute; lower glume i as 

 long as the upper, smooth and 5-veined one ; abortive pales equal, staminate ; 

 fertile fl. ovate. — Damp soils, about N. Orleans (Hale). 



26 P. miliaceum L. MKiLET. Lvs. lance-linear and sheaths hairy ; culm 

 2 to 3f high ; pan. large, open, nodding ; spkl. solitary, ovate ; gls. acuminate- 

 muoronate, subequal ; pales obtuse. — Cultivated. \ Turkey. 



27 P. Jumentomm. Pers. Another cultivated .<!pecies, from N. Africa, 

 Much -valued South. It is tall, stout, smooth. The spikelets are singularly 

 arranged in 2s or 3s, one or two sterile to each fertile. Seeds black. 



19. OPLIS'MENUS Beauv. Cock-spur Grass. (Gr. OTrXicfia, ar- 

 mament, iievog, courage ; alluding to the stout awns.) Spikelets, <fcc. 

 as in Panicum, except that the lower abortive pale (and often the 

 glumes) is prolonged more or less into an awn. — Coarse grasses with 

 the fls. in dense paniculate racemes. 



1 O. Crus-gdlli Kunth. Barn-tard Grass. - Terete, smooth, 3 — i? high ; fe. 

 linear-.lanceolate, flat, serrulate, with smooth, striate sheaths and- no stipule; pan. 

 simple or apparently so, branc?ies spike-form, compound, alternate and in pairs; 

 rachis hairy and rough ; glumes scarcely atoned, hispid-bristly ; lower abortive 

 palea ending in a rough awn, 6" to 18'' long; fertile fl. ovate. — (D Acoarsa weedy 

 grass, introduced into cultivated grounds, barn-yards, Ac, common. Aug., Sept 

 § Tariable. (Panicum, L.) 



13. MDTicua Awns very short, or the pale merely subulate-pointed. Common. 

 y. HISPIDUS. Sheaths very bristly; awns very long. 



2 O. hirtellus K. & S. Culm glabrous, decumbent, branched; lvs. lanceolate, 

 flat, 1 to 2' by 2 to 4", with scattered, appressed hairs on the upper surface; 



