146 



GRAMINEAE. 



VOL. I. 



26. Panicum laxiflorum Lam. Lax-flowered 

 Panic-grass. Fig. 336. 



Panicum laxiflorum Lam. Encycl. 4: 748. 1797. 

 Panicum xalapense H.B.K. Nov. Gen. & Sp. i : 103. 1816. 



Culms erect, 8'-i6' tall, simple, glabrate, the nodes 

 barbed. Sheaths shorter than the internodes, hirsute 

 with reflexed hairs ; blades 2i'-s' long, 2"-s" wide, 

 erect, generally narrowed at base, long-acuminate, pubes- 

 cent or glabrous, excepting the ciliate margin ; panicle 

 2'~4' long, its axis and erect or spreading lax branches 

 sometimes hirsute; spikelets about i" long, ellipsoid or 

 narrowly obovoid, strongly pubescent ; first scale minute, 

 i-nerved; second and third about equal, p-nerved, very 

 pubescent, as long as the shining obtuse minutely apicu- 

 late fourth one; third scale usually with an empty palet. 



Moist soil, Maryland to Missouri, south to Florida and 

 Mexico. Cuba and Haiti. June-Aug. 



27. Panicum angustifolium Ell. Narrow-leaved 

 Panic-grass. Fig. 337. 



Panicum angustifolium Ell. Bot. S. C. & Ga. i: 129. 1817. 

 Panicum consanguineum S. Wats, in A. Gray, Man. Ed. 6, 

 633, in part. 1890. Not Kunth, 1835. 



Culms erect, i-2 tall, glabrous or pubescent toward 

 the base, at first simple, later profusely branched above. 

 Sheaths glabrous or the basal ones pubescent, those on 

 the culm shorter than the internodes, those on the branches 

 crowded ; blades elongated, 3'-6' long, i"-3" wide, nar- 

 rowed to the base, firm, glabrous, those of the culm dis- 

 tant, those of the branches shorter and crowded; primary 

 panicle long-exserted, ii'-3i' long, its branches spreading; 

 lateral panicles smaller, shorter than the leaves ; spikelets 

 few, about li" long, elliptic to obovoid; first scale one- 

 fourth to one-third as long as the spikelet; second and 

 third oval, 9-nerved, pubescent; fourth oval, minutely 

 pubescent at the apex. 



Dry soil, Pennsylvania to Florida and Texas. June-Aug. 



28. Panicum aciculare Desv. Grisebach's 

 Panic-grass. Fig. 338. 



Panicum aciculare Desv. ; Poir. in Lam. Encycl. 4 : 274. 



1816. 

 ? Panicum neuranthum Griseb. Cat. PI. Cub. 232. 1866. 



Culms tufted, slender, at length much branched, 

 the primary simple, erect, glabrous or pubescent, 12'- 

 30' tall. Sheaths glabrous, or the lower pubescent, 

 the primary about one-half as long as the internodes, 

 those on the branches overlapping ; ligule a ring of 

 hairs ; blades smooth and glabrous, the primary 

 erect, acuminate, i'-4' long, \"-2.\" wide, those on 

 the branches shorter, erect or ascending, usually 

 involute when dry, concealing the small secondary 

 panicles; primary panicle i'-4' long, its branches at 

 first erect, at length widely spreading; spikelets 

 numerous, broadly obovate, about i" long, densely 

 pubescent with short spreading hairs, the second and 

 third scales 7-nerved. 



Dry or moist soil along the coast. New Jersey to Flor- 

 ida and Texas. Recorded from West Indies. June-Oct. 



