Part 3, 1915] POACEAE 273 



172. Panicum chamaelonche Trin. Gram. Pan. 242. 1826. 



Panicumnitidum minus Vasey, Contr. U. S. Nat. Herb. 3: 30. 1892. 



Panicum Baldwinii Nutt.; Kearney, Bull. U. S. Dep. Agr. Agrost. 1: 21. 1895. 



Vernal phase densely tufted; culms 10-20 or even 30 cm. high, ascending, glabrous, the 

 nodes glabrous; leaf-sheaths, except the basal ones, half as long as the internodes or less, at 

 least the upper rather loose, glabrous or occasionally with a few cilia on the margin; ligule 0.2 

 mm. long; blades firm, ascending or spreading, 1.5-4 cm., rarely 5 cm. long, 2-3 mm. wide, 

 more or less involute-pointed, glabrous on both surfaces, often with a few long, stiff hairs on 

 the margin near the base; panicles finally long-exserted, 2.5-5 cm. long, nearly as wide, the 

 flexuous branchlets and pedicels spreading at nearly right angles; spikelets 1.1-1.2 mm. long, 

 0.6 mm. wide, obovate, obtuse, turgid, glabrous; first glume one fourth to one third as long as 

 the spikelet, obtuse; second glume slightly shorter than the fruit and sterile lemma; fruit 0.9-1 

 mm. long, 0.6 mm. wide, elliptic, subobtuse. 



Autumnal phase freely branching from the base and lower nodes, the early branches often 

 as long as the primary culms, repeatedly branching, forming dense cushions, as much as 50 

 cm. across, the longer culms upturned at the ends; ultimate branchlets more or less fascicled, 

 the scarcely reduced blades drying involute, overtopping the small panicles; winter rosettes 

 usually persisting green during the vernal state, the rather firm blades 2-5 cm. long. 



Type locality: North America. 



Distribution: North Carolina to Florida and Mississippi. 



Illustrations: Bull. U. S. Dep. Agr. Agrost. 17: /. 358; Contr. U. S. Nat. Herb. 15: /. 297. 



173. Panicum glabrifolium Nash, Bull. Torrey Club 24: 196. 1897. 



Vernal phase similar to that of P. chamaelonche, in smaller tufts; culms stouter, more or 

 less flattened, 15-50 cm. high, erect or sometimes sub geniculate at base; blades firm, erect, or 

 narrowly ascending, 4^12 cm. long, or the lower occasionally as much as 20 cm. long, 2-4 mm. 

 wide, usually involute at least toward the apex, glabrous; panicles 4-9 cm. long, two thirds to 

 three fourths as wide, the branches ascending., the ultimate branchlets and spikelets more or 

 less secund along the lower side of the branches; spikelets 1.2—1.4 mm. long, obovate, obtuse, 

 turgid, glabrous; first glume about one third as long as the spikelet; second glume shorter than 

 the fruit and* sterile lemma; fruit 1.1—1.2 mm. long, elliptic. 



Autumnal culms wiry, elongate, and spreading, with geniculate nodes and long internodes, 

 freely branching from the middle and upper nodes, the blades long and narrow, overtopping 

 the somewhat reduced panicles; winter leaves less numerous than in P. chamaelonche, as much 

 as 10-15 cm. long, stiffly ascending. 



Type locality: Tampa, Florida. 



Distribution: Florida. 



Illustrations: Bull. U. S. Dep. Agr. Agrost. 17: /. 387; Contr. U. S. Nat. Herb. 15: /. 299. 



174. Panicum breve Hitchc. & Chase, Contr. U. S. Nat. Herb. 15: 



271. 1910. 



Vernal phase purplish; culms in dense tufts, 5-17 cm. high, erect, stiff and wiry, glabrous 

 or appressed-pubescent below; leaf-sheaths crowded at the base as in species of Festuca, those 

 of the culms usually longer than the internodes, ciliate on the margin, otherwise glabrous; 

 ligule dense, about 0.3 mm. long; blades firm, erect or ascending, 3-6 cm., sometimes 8 cm. long, 

 about 1.5 mm. wide when flattened out, strongly involute, more or less falcate, sometimes 

 strongly so, a few long, stiff hairs on the margin toward the base, otherwise glabrous; panicles 

 short-exserted, 1.5-4 cm. long, nearly as wide, loosely flowered, the flexuous branches spreading; 

 spikelets 1.3-1.4 mm. long, obovate, obtuse, turgid, puberulent; first glume one third to half 

 as long as the spikelet; second" glume and sterile lemma barely equaling the fruit at maturity; 



fruit 1.2 mm. long, elliptic. 



Autumnal phase erect, branching from the middle nodes, the fascicled branches strict,the 



reduced wiry blades overtopping the panicles. 



Type locality: Jensen, Florida. 

 Distribution : East coast of Florida. 

 Illustration: Contr. U. S. Nat. Herb. 15: /. 301. 



