32 



40. P. scoparium Lam. (P. paucifiorum, Ell). — Culms erect, becom- 

 ing branched and reclining, 1 to 2 feet high, somewhat scabrous ; leaves 

 erect, about 3 iuches long, 4 to 5 lines wide, faintly nerved, scabrous on 

 the margins, hairy fringed near the base, the sheaths bristly with stiff, 

 spreading hairs, or smoothish; the panicle 2 to 3 inches long, spreading, 

 open, branches smooth, mostly simple, alternate, rather few flowered; 

 spikelets 1J to If lines long, oval to obovate, hairy or smoothish, lower 

 glume about one- third as long as spikelet. 



New Eu gland to California and southward. A widespread species. 



(a) Var. major (P. scoparium, EU.). — This differs from the preceding 

 in its stouter, rougher culm, larger leaves, 4 to G inches Jong, three- 

 fonrths of an inch wide (1 to 1J inches wide, Elliott), which are soft- 

 pubescent below, and its spikelets 2 lines long. 



We have only seen this from South Carolina (Dr. Eavenel). 



(b) Yar. angustifolium. — Culms tall and erect, 2 to 3 feet high, branch- 

 ing; leaves longer and narrower than the type, 3 or 4 inches long, 3 to 

 4 lines wide, rather rigid, sheaths sparsely pubescent; panicle long-ex- 

 serted, 3 to 4 inches long. 



South Carolina (Dr. Eavenel); Illinois (Dr. Schenck); Fortress Mon- 

 roe, Va. (Vasey). 



(c) Yar. Liebergii (P. Liebergii, Scrib.). — Culms tall and erect, un- 

 branched, 2 feet high; leaves lanceolate, distant, 3 to 4 inches long, G to 

 9 lines wide, scabrous or papillose, hairy, about eleven-nerved, sheath 

 shorter than the internodes, ciliate, or the margins somewhat scabrous 

 and sparsely hairy, panicle about 3 inches long, 1 inch wide, the fewish 

 branches erect-spreading and few-flowered; spikelets obovate, obtuse, 

 If lines long, tho outer glumes papillose, hairy, lower glume ovate or 

 ovate-lanceolate, pointed, nearly half as long as spikelet, second glume 

 seven-nerved, third glume nine-nerved, equaling the flower, having a 

 hyaline palet of nearly its own length, and inclosing three stamens. 



Plymouth County, Iowa (John Lieberg). 



41. P. Wilcoxianum, Vasey. — Culms about G inches high, entire or 

 sparingly branched and with the leaves more or less white-hairy; leaves 

 linear-lanceolate, erect, acuminate, 2 to 3 inches long, hairy both sides, 

 rather rigid, sheaths striate, hairy, mostly longer than the internodes, 

 ligule obsolete; panicle oblong, rhachis zigzag, 1 inch long, lower 

 branches subverticillate, short, spikelets about 1J lines long, pubescent, 

 lower glume ovate, one-fourth as long as the spikelet, second and third 

 glumes with five to seven broad nerves, the third hardly as long as the 

 flowering glume. 



Nebraska (Dr. T. E. Wilcox). 



42. P. sphserocarpon, EU. — Culms 15 to 24 inches long, 5to 7 lines wide, 

 lanceolate, acute, obscurely nerved, smooth except at the ciliate cordate 

 base, sheaths shorter than the joints, smooth ; panicle 3 to 4 inches long, 

 spreading, spikelets oval, five-eighths to three fourths of a line long, 



