HITCHCOCK AND CHASE — NORTH AMERICAN PANICUM. 313 



branches appear, loose, strongly papillose-hispid to nearly glabrous, a puberulent ring 

 at the summit; ligules 0.5 mm. long; blades spreading or finally reflexed, 10 to 20 

 cm. long, 1.2 to 3 cm. wide, slightly tapering to the cordate-clasping base, acuminate, 

 scabrous on both surfaces, at least toward the end, usually ciliate at the base; panicles 

 finally rather long-exserted, 8 to 15 cm. long, about three-fourths as wide, many- 

 flowered, the flexuous branches in distant fas- 

 cicles, short spikelet-bearing branchlets in the 

 axils; spikelets 2.7 to 3 mm. long, 1.4 to 1.5 mm. 

 wide, obovate-oblong, sparsely pubescent; first 

 glume one-third the length of the spikelet, sub- 

 acute or obtuse; second glume slightly shorter 

 than the fruit and sterile lemma; fruit elliptic 

 2.1 to 2.3 mm. long, 1.2 to 1.3 mm. wide. 



Autumnal form erect or leaning, sparingly 

 branching, often before the maturity of the 

 primary panicle, from the middle and upper 

 nodes, the branches leafy, the swollen, bristly 

 sheaths overlapping on the shortened internodes and inclosing wholly or partially the 

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



Occasional specimens, such as the type of P. decolor atum, and Eggert 114 and 253, 

 Merrill 198, and one specimen of Small & Heller, Blowing Rock Mountain, Tenn., in 

 1891 (a second being the ordinary form) are bristly only on the lower sheaths, the upper 

 glabrous or only scabrous. This lack of pubescence is not found to be correlated with 

 smaller spikelets nor with scarcely-exserted panicles. In Andreios 11 the spikelets 

 are exceptionally small, only 2.5 mm. long, but the sheaths and culms are bristly, 

 and the developed panicle is long-exserted and an immature one scarcely exserted. 



Fig. 353.— p. clandestinum. From type speci- 

 men of P. pedunculatum Torr. 



DISTRIBUTION. 



/ 



Moist, mostly sandy ground, Maine to Kansas, south to Florida and Texas. 

 Maine: Foxcroft, Fernald 292, 518; Farmington, Chamberlain & Knowlton in 



1902. 

 New Hampshire: Gilford, Career 111 (Hitchcock Herb.). 

 Vermont: Burlington, Flynn in 1900 (Hitchcock Herb.). 

 Massachusetts: South Hadley, Cooh in 1887. 

 Connecticut: Pine Meadow, Bissell 5544; Southington, Andrews 11, Bissell 5546; 



South Manchester, IIitchcoch^585; South Glastonbury, Wilson 17; Greens 



Farms, Pollard 92; Oxford, 



Harger in Kneucker Gram. 



Exs. 424. 

 Rhode Island: Without locality, 



Congdon (Hitchcock Herb.). 

 New York: Oneida County, Ha- 



herer 1257. 

 New Jersey : Clifton, Nash in 1891 ; 



Stockholm, Van Sickle in 1895; 



Woodbury, Smith 112; South 



Amboy, Mackenzie 1360; Wild- 

 wood, Chase 3513. 

 Pennsylvania: Easton, Porter in 



1895 and 1897; Refton, Heller in 1901; Mount Hope, Heller 4781; TuUytown, 



Bicknell in 1899. 

 Ohio: Berea, Ashcroft in 1897; Cadiz Junction, Kellerman 6799^; New Ply- 

 mouth, Kellerman 6883; Vinton, Kellerman 6888. 



Fig. 354.— Distribution of P. clandestinum. 



