276 NORTH AMERICAN FLORA [Volume 17 



long; blades firm, erect or ascending, 5-8 cm. long, 3-6 mm. wide, broadest toward the base 

 (this scarcely wider than the wide sheath), commonly involute-acuminate, long-hirsute on 

 both surfaces; panicles finally exserted, often equaled or exceeded by the upper blades, 2-5 cm. 

 long, about half as wide, or sometimes more expanded at anthesis, rather densely flowered; 

 spikelets 2.7-3 mm. long, 1.5 mm. wide, obovate-elliptic, papillose-pubescent; first glume about 

 one third as long as the spikelet, pointed or obtuse; second glume slightly shorter than the fruit 

 and sterile lemma; fruit 2.4^2.5 mm. long, 1.3-1.4 mm. wide, elliptic. 



Autumnal phase branching from all the nodes, forming bushy tufts with rigid, erect blades 

 much overtopping the reduced panicles ; branches appearing early, usually before the maturity 

 of the primary panicles; secondary spikelets usually more turgid than those of the primary 

 panicles. 



Typb locality: Nebraska. 

 Distribution: Manitoba to Iowa and Kansas. 



Illustrations: Bull. U. S. Dep. Agr. Agrost. 17: /. 391; Contr. U. S. Nat. Herb. IS: /. 313; 

 Britt. & Brown, 111. Fl./. 260; ed. 2./. 375. 



181. Panicum malacophyllum Nash, Bull. Torrey Club 24: 198. 1897. 



Panicum scoparium minus Scribn. Bull. Tenn. Exp. Sta. 7: 48. 1894. 



Vernal phase velvety or velvety-pilose throughout; culms slender, few to several in tufts, 

 25—70 cm. high, more or less geniculate at base with arched internodes, ascending or spreading, 

 papillose-pilose with soft, reflexed hairs, the nodes retrorsely bearded; leaf-sheaths loose, shorter 

 than the internodes, usually less copiously pilose than the culm; ligule 1—1.5 mm. long; blades 

 spreading or ascending, 7-10 cm. long, 6-12 mm. wide, tapering to the rounded base, acuminate, 

 rather thin, velvety on both surfaces, ciliate at least toward the base; panicles usually short- 

 exserted, 3-7 cm. long, at first narrow, the lower branches finally spreading, with short, spike- 

 let-bearing branchlets in the axils; spikelets 2.9-3 mm. long, 1.5-1.7 mm. wide, elliptic-obovate, 

 obscurely pointed, turgid at maturity, papillose-pilose; first glume about one third as long as 

 the spikelet; second glume and sterile lemma equaling the fruit at maturity; fruit 2.2 mm. long, 

 1.5 mm. wide, elliptic. 



Autumnal phase spreading, freely branching from the middle and upper nodes before the 

 maturity of the primary panicle, at length forming bushy, topheavy clumps with reduced blades 

 and numerous secondary panicles. 



Typ$ locality: Sapulpa, Indian Territory [Oklahoma]. 

 Distribution: Tennessee to Oklahoma and eastern Texas. 



Illustrations: Bull. U. S. Dep. Agr. Agrost. 17: /. 392; Contr. U. S. Nat. Herb. 15: /. 315; 

 Britt. & Brown, 111, Fl. ed. 2./. 378. 



182. Panicum Helleri Nash, Bull. Torrey Club 26: 572. 1899. 



Panicum pernervosum Nash, Bull. Torrey Club 26: 576. 1899. 



Vernal phase in clumps of few to several culms, light-green, usually somewhat bluish; 

 culms 25-60 cm. high, slender, ascending or spreading, the lower internodes appressed-pilose, 

 the upper often glabrous; leaf-sheaths sparsely papillose-hispid to glabrous, the papillae often 

 without hairs as in P. Scribnerianum, ciliate on the margin; ligule about 1 mm. long; blades 

 ascending or spreading, measuring about the same as those of P. Scribnerianum, but broadest 

 about the middle, rather thin, glabrous on both surfaces or pubescent beneath, ciliate toward 

 the base; panicles finally rather long-exserted, 6-12 cm. long, about three fourths as wide, more 

 open and loosely flowered than in P. Scribnerianum; spikelets 2.9-3 mm. long, 1.6-1.7 mm. wide, 

 obovate, turgid, blunt, glabrous, or with few scattered hairs; first glume about one third the 

 length of the spikelet, acute; second glume and sterile lemma subequal, slightly exposing the 

 fruit at maturity, strongly nerved; fruit 2.4-2.5 mm. long, 1.5-1.6 mm. wide; oval, obscurely 

 apiculate. 



Autumnal phase branching at all but the lowest nodes, forming loose sprawling tufts, 

 the branches somewhat divaricate, with sheaths more commonly pubescent than those of the 

 primary culm, the blades widely spreading, not much reduced, the long-pediceled spikelets 

 rather conspicuous among the foliage. 



Type locality; Kerrville, Texas. 



Distribution: Missouri to Louisiana and New Mexico. 



Illustration: Contr. IT. S. Nat. Herb. 15: /. 317. 



