OBDKB 156. GRAMINE.&. 783 



13 P. Digitaria Poir. Mostly glabrous ; culm erect from an inclined base, 1 to 

 2|f high; Ivs. lance-linear, fiat, 6 to 16' by 5 to 8", on long sheaths; spikes a 

 pair, conjugate, slender, 2 to 4' long, at top of the long naked ped. or upper inter- 

 node of culm spikelets lanceolate, in 2 opposite rows on the vertically compressed 

 flexuous rachis. (X ? Damp pine woods, Va. to Fla. and La. (Millium paspa- 

 loides E1L P. Michauxiana Kth.) 



14 P. tristachyum Le Conte. Glabrous, decumbent below, 12 to 20' high; 

 culm filiform above ; Ivs. linear, fiat, 3 to 8' by 2 to 3", margins sparingly ciliate ; 

 sheaths compressed; spikes usually 3, approximate (the 2 highest paired), very 

 slender; rachis flexuous, triquetrous; spikelets lanceolate, 2-rowed, whitish. 

 1" long, close-pressed, gll and pale scarcely longer than the flowers. (I) "Wet 

 places, Ga. Fla. to La. 



15 P. conjugatum Berg. Nearly glabrous and erect, 1 to 2f, slender; Ivs. 

 broadly linear, 2 to 4' by 2 to 4", on compressed sheaths ; upper sheath very long 

 and nearly leafless ; spikes 2, a conjugate pair, on the filiform upper internode, 

 very slender, 2 to 3' long; rachis nearly as wide as the 2 rows of minute (%" long), 

 round-ovate, acute, white, ciliate spikelet-s. (I) Waste places about N. Orleans 

 (Hale). 



16 P. distyclram L. Nearly glabrous: culms some inclining at base, 12 to 18' 

 high; Ivs. lance-linear, bearded at the throat, 2 to 3' by 2 to 3" ; spikes 2, a pair 

 nearly or quite conjugate, dense-flowered, 1 to 2-J-' long; rachis narrower than the 



2 rows of ovate, acuminate (\\" long), glabrous spikekts. If. Wet grounds, S. States. 



ft. TRrSTACHUM. Spikes in 3s, closely approximate. 



17 P. ambiguum DC. Glabrous; culms clustered, decumbent, 8 to 15' high; Ivs. 

 lance-linear, shorter than the sheaths (2 to 4' by 2 to 4") ; spikes 2 to 4, about 

 2' long, slender; spikelets crowded, 2-rowed, ovate, f" long, gL and pale about 

 equal, not longer than the purplish flower, both hairy. Sandy fields, especially 

 South. Often purplish. Aug., Sept. Eur. (Panicum glabrum Gaud.) 



18 P. serotinum Fluegge. Decumbent, creeping and rooting, with upright 

 branches ; Ivs. and sheaths villous with white soft hairs, the former lance-linear, short, _ 

 about 1' by 2" ; spikes digitate, about in 5s, slender, 2 to 3' long; rachis flat, 

 about as wide as the 2 rows of elliptical spikelets (i"); spikelets all pedicellate. 

 in 2s; gl. a fourth as long as the striate pale, and flower. Sandy fields, Car. to 

 Fla. and La. Forms a dense carpet. JL Oct (Digitaiia villosum E1L) 



19 P. sanguinale Lam. PURPLE FINGER GRASS. CRAB GRASS. Culms de- 

 cumbent at base, radiating and branching at the lower joints, 1 2f; Ivs. linear- 

 lanceolate, on long, loose sheaths, softly pilous, the sheaths strigously hairy ; spikes 

 3 5' long, fascinate at the top of the stem, 5 to 9 together ; spikelets in pairs, 

 oblong-lanceolate, closely appressed to the flexuous rachis, in 2 rows, glume -J- as 

 long as the flower. CD Common in cultivated grounds, N. Eng., W. Ind. Aug. 

 Oct. (Panicum, L. Digitaria, Scop.) 



20 P. filiforme Swartz. Culm erect, filiform, simple, 12 18'; Ivs. short, nearly 

 smooth, narrow-lanceolate; lower sheaths very- hairy, upper glabrous; spikes 

 2 4, filiform, erect; rachis flexuous; spikelets in 3s, all pedicellate; glume soli- 

 tary, as long as the pale (abortive flower). CD Dry, gravelly soils, N. Y. to Ky. 

 Aug. (Panicum, L. Digitaria, Muhl.) 



21 P. int en-upturn. Culm strictly erect, wiry, tall (2 to3f); Ivs. long, linear, 8 

 to 15' by 3 to 4", clothed with copious soft hairs, as well as the sheaths; spikes 



3 or 4, raceme-like, 2 to 6' long, the spikelets ovate, acutish, in remote pairs dis- 

 tinctly pedicellate, rachis filiform. Dry soils, La, and Tex. (Hale). (P. racemosum 

 Xutt uec Jacq.) The inflorescence is almost paniculate. 



16. MIL'LIUM, L. MILLET GRASS. (Probably from the Latin mille,. 

 a thousand, on account of its fertility.) Spikelets 1 -flowered, not articu- 

 lated with their pedicels; glumes 2*, without involucre or awns; pales 

 2, shorter than the glumes, awnless, oblong, concave, persistent and car- 

 tilaginous, coating the caryopsis. (Comparing Millium with Panicum,. 

 it appears that the 2 glumes of the former are, in fact, a glume, and a. 



