Nash : The dichotomous Panicums 570 



2.5-3.5 cm. long, its slightly hispid branches widely spreading, the 

 larger 1.5-2 cm. long: spikelcts about 1.5 mm. long and about 

 0.75 mm. wide, elliptic, the scales glabrous, the first scale about 

 one third as long as the spikelet, broadly ovate, obtuse, i -nerved, 

 the second and third scales 7-nerved, the second shorter than the 

 third, the fourth scale about equalling the third, about 1.25 mm. 

 long and about 0.6 mm. broad, yellowish-white, ob.scurely apiculate. 

 Collected by S. M. Tracy at Ocean Springs, Mississippi, May 

 2, 1898, no. 4598. Related to P. lucidicin As\\e,hn{. distinguished 

 by its smaller spikelets and sparsely pubescent sheaths. 



Panicum decoloratum 



A more or less purplish tufted perennial, glabrous, with the ex- 

 ceptions noted below. Culms 4-6 dm. tall, stout, finally branched, 

 the nodes barbed : leaves 5 or 6, extending to the base of the 

 panicle, the upper one including its base ; sheaths loosely embrac- 

 ing the culm, usually overlapping and hence concealing the culm, 

 the lower and basal ones papillose-hirsute between the nerves, the 

 hairs of the former early deciduous, the upper sheaths ciliate on 

 the external margin and with a minutely pubescent ring at the 

 apex ; blades erect or ascending, variously colored with black- 

 purple, broadly lanceolate, a little rough on both surfaces, especially 

 above, cordate-clasping at the base, 7-12 cm. long, 1.2-2 cm. wide, 

 minutely serrulate and very rough on the margins : panicle in- 

 cluded at the base, its branches hispidulous : spikelets on hispid- 

 ulous pedicels, 2.7 mm. long and 1.3 mm. wide, elliptic, the first 

 scale from nearly orbicular to broadly ovate, about one third as 

 long as the spikelet, i -nerved, obtuse or rounded at the apex, 

 glabrous, the second and third scales rather sparingly pubescent 

 with ascending hairs, 9-nerved, the second scale a little shorter than 

 the third, the fourth scale slightly yellowish-white, about 2.4 mm. 

 long and i mm. wide, obtusely and rather obscurely apiculate, 

 minutely pubescent at the apex. 



Collected by Mr. E. P. Bicknell on a sandy railroad bank at 

 TuUytown, Pennsylvania, May 30, 1899. The panicle in the ma- 

 terial at hand may not be fully developed, and so a later stage 

 may show it exserted instead of included at the base. In habit 

 much resembling P. clandestimim, but that species is larger in 

 every way, the pubescence is harsh and hispid and occurs on all 

 the sheaths, the blades are much longer and with the margins near 

 the base conspicuously ciliate with long stiff hairs, and the spike- 

 lets are larger (exceeding 3 mm. in length). 



