8 P. Vilfiforme. Glabrous throughout; culm decumbent, ascending 2 to 3f, branched; lvs. long, linear, scarcely rough-edged; sheaths with a tuft of hairs at throat; pan. simple, with racemed, spreading branches; spikelets 2" long, lanceolate, acute; lower glume 1/4 to 1/3 as long as the upper, 1-veined glume which is shorter than the lower pale (while in Nos. 6 and 7 it is longer than the lower pale I). - Wet meadows, E. Tenn. ! Jl., Aug.

D P. amarum Ell. Glabrous, leafy; culm 2 to 3f high, stout; lvs. glaucous, cor iaceous, rigid, linear, 10 to 18' long, margins involute, not scabrous; sheath some shorter than the joints; pan large, contracted, its very smooth branches appressed; spikelets thick, 2" long, ovate, acuminate, lower glume nearly as long as the sterile pales, which contain 3 orange-colored stamens. -Order CLVI Gramineae Grasses Part 10 2527 Sandy shores, Conn to Fla. and La, (Hale) Lvs. excessively bitter (Elliott). Aug. - Oct.

10 P. virgatum L. Glabrous and often purple; culm 3 - 5f high; lvs, flat, long, linear-lanceolate, hairy at base; sheaths striate; stip. with long, white ciliae; pan. pyramidal, loose, spreading, diffuse, very large; fls. acuminate, the glumes 2 1/2' long, very pointed, divaricate, the lower 2/3 as long as the upper; pales of the abortive flower nearly equal, enfolding the purple stamens.-Order CLVI Gramineae Grasses Part 10 2528 Salt-lick prairies, fields, etc., N. Y. to Ind., S. to the Gulf. Aug.

11 P. verrucosum Muhl. Culm slender, decumbent and geniculate, branching from the base, 1 - 2f high; lvs. lance-linear, flat, 4 to 6 by 2 to 4", spreading, smooth; pan. much expanded, few-flowered; spikelets 1/2 to 1/3 long, covered with warty points (verrucous) obovate, bluish; abortive flower of one palea, and neuter. -

Order CLVI Gramineae Grasses Part 10 2529 ? Swamps and thickets, Mid. and S. States. Panicles terminal and lateral, loose and capillary. Aug. (P. debilis Ell. nec Poir. P. ramulosum Mx)

12 P. fragile Kunth. Culm geniculate at base, assurgent, branched, very brittle,

If; lvs. subulate, scabrous, 2 to 4' long; sheaths glabrous, longer than the jointa; pan. very simple, the few, solitary, small spikelets on very long setaceous pedicels; lower glume subulate; sterile pale single, as long as the 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; lvs. flat, erect, 2 to 3' by 3 to 4"; sheaths much shorter than the joints; pan. small (2 to 3' long), loose; spikelets oval, 1" long, green; lower glume roundish, 1/4 as long as the 7-veined, upper one, which equals the single, sterile pale and fertile flower. - Evergreen in damp places, S. States (Feay, &c). Apr., May.

14 P. ciliatiflorum. Fringed Grass. Culm erect, strict, 1 to 3f, glabrous; lvs. 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 the leaves more or less hairy, and the Curious silk fringe of the spikelets more or less copious. In pine barrens, S. States. Sept. (Phalaris viilosa Mx. Aulaxanthus ciliatus and rufa Ell. P. ignoratum Kth., an absurd name 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; lvs. 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 1/2" long), oval or roundish; lower glume very small, upper equaling the sterile pale and fertile flower, upper sterile 1/3 to 1/2 as long as the lower, scarious, bifid. -Order CLVI Gramineae Grasses Part 10 2530 Common everywhere, in meadows, fields and woods. Jn. - Sept. - The following are the more striking forms of this exceedingly variable species (which includes P. nodiflorum, laxiflorum, nitidum Lam., barbulatum Mx., sphaerocarpa Muhl., lanuginosum, ensiforum Ell., &c).

β. NITIDUM. Smooth and shining; spikelets pale purple; upper pale very short. γ . spheaerocarpum. Hairy; lvs. suberect; spikelets dark purple; upper pale deeply bifid. δ. barbulatum. Taller; nodes with a ring of retrorse hairs; lvs. spreading; spikelets purplish; upper pale entire. є. lanuginosum. Woolly; lvs. linear-lanceolate; spikelet3 green; upper pale elongated, very obtuse. Approaches the next species.

16 P. depauperatum Muhl. Culm csespitous, erect, 9 to 12' high, simple above the base; lvs. linear, rigidly erect, lower short, upper about 5' by 2 1/2"; pan. simple with ascending branches, the peduncle very short or becoming very long; spikelets green, oval, acute, 2/3 to 1" long; outer glume roundish, 1/3 as long as the inner, 7-veined one; upper neutral pale (always?) bifid, half as long as the lower. - Hilly woods, N. States and Can. Jn. (P. rectum R. & S.)

β. involutum. Lvs. involute, ending in a long, rigid point. (P. involutum, . Torr.)

17 P. pauciflorum Ell. Culm mostly erect, at length, somewhat decumbent and branched; lvs. erect, linear-lanceolate, faintly 9-veined, tapering to near the base; 3 to 5' by 5 to 7", sparingly hirsute as well as the close sheaths; pan. exserted, simple, raceme-like, few-flowered; spikelets 10 or more, obovate, obtuse, 1" long; lower glume broad-ovate, 1/2 as long as the upper one; upper neutral pale 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; lvs. 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 largo (1 1/2 'long), hairy, oval, obtuse, green; outer glume, lanceolate, 2/3 as long as the inner 9-veined one; inner neutral pale nearly as long as the outer. - Dry fields, etc., N. Y. to Ohio and S. States. Jn. (P. dichotomum β. Gray.)