HITCHCOCK AND CHASE NORTH AMERICAN PANICUM. 55 



Panicles not more than one-third the entire height of 

 the plant. 

 Spikelets not over 2 mm. long, acute but not long- 

 acuminate. 

 Culms stout; blades about 1 cm. wide; 



spikelets turgid 21. P. gattingeri. 



Culms slender; blades not over 6 mm. wide; 



spikelets not turgid 22. P. philadelphicum. 



Spikelets 2.7 to 6 mm. long, acuminate. 



First glume about one-third the length of the 



spikelet, subacute or blunt 27. P. stramineum. 



First glume usually more than half the 

 length of the spikelet, acuminate. 

 Spikelets 4.5 to 6 mm. long. 



Spikelets 6 mm. long, scattered.. 29. P. parcum. 

 Spikelets scarcely over 5 mm. 



long, approximate 26 A. P. decolorans. 



Spikelets not over 4 mm. long. 



First glume more than three-fourths 

 the length of the spikelet; 



spikelets 4 mm. long 26. P. pampinosum. 



First glume half to two-thirds the 

 length of the spikelet; spike- 

 lets not over 3.3 mm. long. . . 25. P. hirticaule. 



20. Panicum flexile (Gattinger) Scribn. 



Panicum capillare flexile Gattinger, Tenn. Fl. 94. 1887. "Characteristic of the cedar 

 glades." In the Gattinger Herbarium are two specimens labeled "Panicum capillare 

 L. var. flexile Gattinger" in Gattinger's hand. The larger specimen is chosen as the 

 type. This is labeled "Cedar glade near Nashville, Sept. '88. A. Gattinger." 



Panicum flexile Scribn. in Kearney, Bull. Torrey Club 20: 476. 1893. Based on 

 P. capillare flexile Gattinger. 



Panicum minus Nash, Bull. Torrey Club 22: 421. 1895. Based on "Panicum 

 capillare var. minus Muhl.," though Nash's description applies to P. philadelphicum. 



Scribner and Merrill « applied to this species the name P. philadelphicum Bernh., 

 but this name belongs to a different species. Muhlenberg & describes P. flexile as a 

 variety of P. capillare, but without giving a varietal name, saying, "Varietas minor 

 occurrit ubique in cultis magis aridis," and following this by a description. This 

 specimen in the Muhlenberg Herbarium is labeled, "183 Panicum capillare var. 

 minor." 



Pursh c describes P. flexile under the name of P. diffusum Swartz. It was also 

 described by Trinius d as P. capillare /? Panicula depauperata. 



DESCRIPTION. 



Plants erect, much branched from the base, 20 to 70 cm. high; culms slender, 

 glabrous, or somewhat hispid below, nodes pubescent; sheaths papillose-hispid, the 

 hairs shorter than in P. capillare; blades erect but not stiff, glabrous or sparsely hispid, 



a U. S. Dept. Agr. Div. Agrost. Circ. 27: 3. 1900. A discussion of "The grasses in 

 the Herbarium of Dr. H. Muhlenberg." 

 &Descr. Gram. 124. 1817. 

 cFl. Amer. Sept. 1:68. 1814. 

 ^Gram. Pan. 215. 1826. See note under P. philadelphicum, p. 58. 



