786 OBDEB 156. GRAMIXEJS. 



If; Ivs. subulate, scabrous, 2 to 4' long; sheaths glabrous, longer than the joints; 

 pan. very simple, the few, solitary, small spikelets on very long setaceous pedicels ; 

 lower glume subulate ; sterile pale single, as long as tho glume, a little longer 

 than the fertile flower, Dry, sandy soils, rare, N. Car. to Ga. 



13 P. villosum E1L Villous throughout with soft white hairs; culm geniculate 

 below, 1 to 2f ; Ivs. flat, erect, 2 to 3' by 3 to 4" ; sheaths much shorter than tho 

 joints; pan. small (2 to 3' long), loose; spikelels oval, 1" long, green ; lower glumo 

 roundish, as long as the 7-veined, upper one, which equals the single, sterile 

 pale and iertile flower. Evergreen in damp places, S. States (Feay, &c.). Apr., 

 May. 



14 P. ciliatiflorum. FRINGED GRASS. Culm erect, strict, 1 to 3f, glabrous; 

 Ivs. erect, long, linear, flat, narrow, scarcely distinct from their sheaths; pan. 

 virgate, subsimple, 3' long; spikelets pedicellate, oval, the glume and lower 

 abortive pale obtuse, subequal, the 5 veins ciliate-fringed with silky, purplish 

 hairs ; upper pale much smaller, oblong ; fertile pales thinly chartaceous, brown 

 or blackish when mature. Varies with tho leaves more or less hairy, and tho 

 curious silk fringe of tho spikelets more or less copious. In pine barrens, S. 

 States. Sept. (Phalaris villosa MX. Aulaxanthus ciliatus and rufa Ell. P. 

 iguoratum Kth., an absurd namo which we venture to discard.) 



15 P. dichotomum L. Culm at first subsimple with a single terminal panicle, 

 becoming more or less branched, with lateral, subsimple panicles ; Ivs. lanceolate, 

 1 to 4' by 2 to 4" or 5", hairy or smooth, as likewise the sheaths; terminal pan. 

 exserted, often long-pedunculate, small (1 to 3' long), oval in outline, loosely few- 

 flowered; spikelets small (about " long), oval or roundish; lower glume very 

 smaU, upper equaling the sterile pale and fertile flower, upper sterile ^ to aa 

 long as the lower, scarious, bifid. If Common everywhere, in meadows, fields 

 and woods. Jn. Sept. The following are the more striking forms of this ex- 

 ceedingly variable species (which includes P. nodiflorum, laxiflorum, nitidum 

 Lam., barbulatum MX., sphasrocarpa Muhl., lanuginosum, ensiforum Ell., &c.). 



ft. NITIDUM. Smooth and shining; spikelets pale purple; upper pale very 



short, 

 y. SPH-EROcl RPUM. Hairy ; Ivs. suberect ; spikelets dark purple ; upper pale 



deeply bifid. 

 <5. BARBULATUM. Taller; nodes with a ring of retrorse hairs; Ivs. spreading; 



spikelets purplish ; upper pale entire. 

 e. LANUGINOSUM. Woolly ; Ivs. linear-lanceolate ; spikelets green ; upper pala 



elongated, very obtuse. Approaches the next species. 



16 P. depauperatum Muhl. Culm casspitous, erect, 9 to 12' high, simple above 

 the base; Ivs. linear, rigidly erect, lower short, upper about 5' by 2}"; pan. 

 simple with ascending branches, the peduncle very short or becoming very long ; 

 spikelets green, oval, acute, f to 1" long; outer glume roundish, as long as tho 

 inner, 7-veined one ; upper neutral palo (always?) bifid, half as long as tho lower. 

 Hilly woods, N. States and Can. Jn. (P. rectum R. & S.) 



ft. INVOLUTUM. Lvs. involute, ending in a long, rigid point. (P. involutum, 

 Torr.) 



17 P. paucifldruxn EU. Culm mostly erect, at length, somewhat decumbent 

 and branched ; Ivs. erect, linear-lanceolate, faintly 9-veined, tapering to near tho 

 base ; 3 to 5' by 5 to 7", sparingly hirsute as well as the close sheaths; pan. ex- 

 serted, simpk, raceme-like, few-flowered; spikelets 10 or more, obovate, obtuse, 

 1" long; lower glume broad-ovate, \ as long as the upper one; upper neutral palo 

 similar to the lower. Wet or shady places, Mid., ~W. and S. States. Jn., Jl. 



18 P. pubescens Lam. Culm slender, finally branched, glabrous, 2 to 3f long ; 

 Ivs. lance-linear, 9-veined, 3 to 6' by 3 to 5", clothed with reflexed hairs as well 

 as the open sheaths; pan. small, expanded, few-flowered, pubescent; spikelets 

 large (1^'long), hairy, oval, obtuse, green; outer glume, lanceolate, f as long as 

 the inner 9-veined one ; inner neutral palo nearly as long as the outer. Dry 

 fields, etc., N. Y. to Ohio and S. States. Jn. (P. dichotomum /3. Gray.) 



19 P. latifdlium L. Culm mostly erect, 1 to 2f high ; Ivs. lanceolate., base dilated 

 and cordate-clasping, 3 to 5' by 1', 11 to I3-veined, smoothish; sheaths hirsute at 

 throat; pan. exserted, compaund, loose, about 3 'long; spikoleta oval, obtuse, 



