Order 156.— GRAMLNEjE. 787 



11" long, green; lower glume ovate, not half as long as tho upper; abortive 

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

 Jn., Jl. (P. scoparium and nervosum Lam. P. ciliatum Ell., etc.) 



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

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

 9 to 11-veined; pan. long-exserted, simple, raceme-like, few-flowered; spkl. round- 

 ish-obovate 1£" long ; lower glume ovate, 3-veined, acutish, £ 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. viscidum Ell. Hoary, with a dense, short, soft, viscid pubescence ; culm 

 decumbent, assurgent 2 to if, stout; joints a smooth brown ring; lvs. lance- 

 linear, 3 to 6' by 6 to 16" ; sheaths much shorter than tho intemodes; pan. rather 

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

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



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

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

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

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

 pale of tho neutral fl. obtuse. — U Moist woods, Mass. and Mid. States. Jl., Aug. 



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

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

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

 striate, smooth; stip. 0; pan. much branched, nearly smooth; spkl. small, \\" 

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

 minute ; fr. shining, bluish white. — 2£ . 



24 P. Walter! Ell. Culm slender, glabrous, erect, 2f ; lvs. linear 3 to 6' 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-veined ; 

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

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



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

 glabrous ; lvs. lanceolate, glabrous, 1 to 2' by 3 to 4", sheaths ciliate ; spikes 

 slender, G to 12" long, alternate, 1 -sided ; spkl. ovate, acute; lower glume •£ 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. Millet. Lvs. lance-linear and sheaths hairy ; culm 

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

 mucronate, 6ubequal ; pales obtuse. — Cultivated. \ Turkey. 



27 P. Jumentorum Pers. Another cultivated species, 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. OTrXio/ia, ar- 

 mament, jj,evog, courage ; alluding to the stout awns.) Spikelets, &c. 

 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 fis, in dense paniculate racemes. 



1 O. Crus-galli Kunth. Barn-yard Grass. Terete, smooth, 3 — if high ; lvs. 

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

 simple or apparently so, branches spike-form, compound, alternate and in pairs; 

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

 palea ending in a rough awn, 6" to 18 7 long; fertile fl. ovate. — (D A coarse, weedy 

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

 § Variable. (Panicum, L.) , 



/?. muticus. Awns very short, or the pale merely subulate-pointed. Common. 

 >'. hispidus. Sheaths very bristly ; awns very long. 



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

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



