ORDEB 156. GRAMIJSE^B. 783 



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

 2f high; Ivs. lance-linear, flat, 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 

 Hexuous rachis. QC ? 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 ; 

 cnlm filiform above ; Ivs. linear, flat, 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, gL and pale scarcely longer than the flowers. (J)\Vot 

 places, Ga. Fia. to La. 



15 P. conjugation 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 liliform upper intercede, 

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

 round-ovate, acute, white, ciliate spikelets, Waste places about N. Orleans 

 (Hale). 



16 P. distichum 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 24-' long; rachis narrower than the 



2 rows of ewafe, acuminate (IV long), glabrous spikelets* If AVet grounds, S. States. 



/3. TuisTACHUM. Spikes in 3s, closely approximate. 



17 P. ambiguum DC. Glabrous; culms clustered, decumbent, 8 to 1 5' 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, $" long, gL and pale about 

 equal, not longer than the purplish flower, loth 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 hai?^s, the former lance-linear, shorL 

 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 (V') ; spikelets all pedicellate, 

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

 Fla. and La. Forms a dense carpet. Jl. -Get (Digitaria villosum E1L) 



19 P. sanguinale Lam. PURPLE FINGER GRASS. CEAB 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 $ a< 

 long as the flower. .1) Common in cultivated grounds, N. Eng., W. Ind. Aug. 

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



20 P. filiforme Swartz. Culm erect, Jiliform, 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). Dry, gra-velly soils, N. T. to Ky. 

 Aug. (Panicum, L. Digitaria, MuhL) 



21 P. interruption. 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 

 Nutt nee Jacq.) The inflorescence is almost paniculate. 



16. MII/LIUM, L. MILLET GRASS. (Probably from the Latin millc, 

 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 



