GRAMINEJ!. 543 



base), narrower than the spikelets ; spikelets 4-3-3erate, oval or oborate-roandish, blunt,. 

 pedicellate, glabresoent : sterile glumes 5-nerved, superior (the third) at length fiat wilhin 

 the tumid, ■margin.— Trin. Ic. t. 140.— P. undiilatum, Pair.— Nearly allied to P. serobicu- 

 latum, L., of the old world, the spikes of which have a broader axis. 2'-3' high, variable in 

 the down ; leaves 4"'-l"' broad ; spikes l"-2", spikelets l"'-li"' long, the latter becoming 

 brown. — Hab. Jamaica !, all coll. ; [United States to Uruguay !]. 

 ^ 76. P. virgatum, L. Csespitose, stout, erect ; leaves long, ilat, glabrous, scabrous at 

 the margin ; spi/ces numerous, one terminal, about as loug as the rest, the other spreading, 

 subapproximate, rarely geminate : axis 3-goual, convex or flattish on the back, scabrous at 

 the margin or ciliate (rarely glabrate), narrower than or as broad as the spikelets ;' spikelets 

 4-sei-iate, obovale or roundish-elliptical, blunt, mucronate, pedicellate, pubescent at the 

 margin or glabrous : sterile glumes h-nemed, superior slightly loosened at the margin. — SI. 

 t. 69./. 2. — Audropogon fasciculatus, L. Sp. ed. ii. {ex Ic. Sl.)—Yeiy variable, 3"-5" 

 high; leaves 8"'-3"' broad ; spikes 3"-5", spikelets 1'" long. 



o. Axis nearly as broad as the spikelets ; glumes becoming brown ; leaves narrow. 



j8. stramineum. Axis half as broad as the spikelets : glumes straw-coloured or at length 

 purplish-tawny, usually glabrous.- — Trin. Ic. t. 131. — Leaves broad or narrow. 



Hab. Tamaica I, Al., March, common in savannahs ! (a, $) ; Antigua !, Wullschl. (j8) ; 

 Trinidad I, Sieb. Tr. 11 ; [Cuba ! and Mexico 1 to Uruguay!]. 



** Spikes numerous, the superior gradually shorter. 



77. P. paniculatum, L. Ca3spitose, erect ; leaves long, broad, hairy or glabresceut, 

 undulate ; spikes numerous, slender, superior shorter, approximate, inferior often 2-3-nate, 

 most curved-spreading : axis 3-gonal, convex or flattish on the back, narrower than the 

 small spikelets ; spikelets 4-3-seriate, roundish or obovate-roundish, blunt, puberulous on 

 the convex side, unequally pedicellate : sterile glumes 3-nerved. — SI. t. 72./. 2. IVin. Ic. 

 t. 127.— P. strictum, Pers. P. polystachyon, Salsm .—2'-3' high; leaves 8"'-12"' broad; 

 inferior spikes 3'' long, spikelets V" djjmi., tinged with brown. — Hab. Jamaica !, all coll. ; 

 Trinidad I, Sch. ; [Cuba ! and California ! to Rio Grande do Sul ! ; Galapagos !]. 



78. P. densum, Foir. Stout, erect; leaves long, glabrous; spikes very numerous, 

 thickish, densely approximate, spreading, superior gradually shorter, most 2-3-nate along 

 the sulcate common axis : special axis 3-gonaI, flat on the back, ciliate with long hairs (or 

 "glabrate"), about as broad as the small spikelets; spikelets 4-seriate, roundish, rounded 

 with a minute blunt point, unequally pedicellate, glabrous : sterile glumes 3-nerved. — Trin. 

 Ic. t. 122. — 4'-5' high; leaves 6"' broad; inferior spikes 3"(-5"), uppermost i'" long; 

 spikelets 1'" diam., straw-coloured. — Hab. S. Vincent!, Guild.; [Cuba! and Mexico! to 

 Brazil !]. 



Seet. 2. Cabkeea, Zag. — Spikelets involucrate by a bundle of yellow bristles. 



79. P. pulchrum, V. Csespitose, erect ; leaves hairy or ciliate at the base ; spikes 

 %-?,,\{-Z)-\.ermmai, most approximate : axis 3-gonal, flat on the back, as broad as the 

 spikelets, ciliate : involucral bristles yellowish, spreading, longer than the spikelets : spike- 

 lets 2-seriate, subsessile, obovate-oblong, blunfish : sterile glumes 3-5-nerved, glabrous or 

 puberulous along the nerves.— .ffM. BAv. t. 164. Trin. Ic. t. 99, 10] .—P. canescens, Ns. I : 

 the hairy form. P. ramosissimum, Us. ! : a form branched at the base. P. chrysostachyum, 

 Schred. : the form with glabrous elumes. P. aureum, Fl. Spruce. P. chrysodactylon. Tr. 

 — 2'-3' high; leaves somewhat rigid, 4"'-2"' broad; spikes 4"-2"(-l"), spikelets i'", 

 bristles 1'" long.— Hab. Trinidad !, Cr. ; [Guiana !, Brazil !]. 



33. DIGITARIA, &o;). 



Character of Faspalum, but fertile glume membranaceous at the margin, and broadly over- 

 lapping the palea. Lowest sterile glume often appearing, but minute. Caryopsis concave- 

 convfjij. rarely flat-convex. — Root mostly annual ; sjiiciform racemes approximate or fasci- 

 cled: i^%.Aa& narrow, in pairs, one pedicellate, the other subsessile: fertile glume placed 



against the axis. 



* Spikes suberect. 



f> 78. D. filiformis, THuhl. (non Koel). Slender, hairy at the base; leaves narrow; 



