275 
Cymhopogon.] clvii. gramine^ (Stapf). 
5. C. commutatus, Stapf in Kew Bulletin , 1907, 211 (excluding 
the specimens). Perennial, up to 4 ft. high, with intravaginal inno- 
vations. Culms erect, terete, simple and about 5-noded below the 
panicle, finely pubescent below the nodes, otherwise glabrous. 
Leaf-sheaths firm, terete, tight, glabrous, smooth or slightly rough 
on the back, the basal up to 4 in. long, more or less persistent ; 
ligules membranous, truncate, up to 1 lin. long, ciliolate ; blades 
linear, tapering to a setaceous point, the inner of the innovations 
very narrow, the outer and those of the culm-leaves over f (probably 
over 1) ft. long, up to over 2 lin. broad, rigid, flat, dull green turning 
russet, glabrous, almost smooth, at least below, more or less rough 
along the margins, midrib very slender, primary lateral nerves 3-4, 
prominent above, obscure below. Spatheate panicle very narrow, 
interrupted below, up to 1 ft. long ; internodes 5-6, lowest up to over 
6 in. long, upper rapidly decreasing in length ; lower leaves of the 
panicle more or less like those lower down on the culm, blade- 
bearing, upper more and more reduced, spathe-like, bladeless ; 
primary branches usually forming up to 6-ray ed fastigiate tiers ; 
lower tiers mixed, rays very finely filiform, slightly unequal, 
even the compound frequently shorter than the supporting spathe 
or sheath ; spathes very narrow, linear, acute, glabrous, those 
of the shortest compound rays often permanently enclosed and 
thin, of the longer exserted, scarious to subherbaceous, up to 1J in. 
long, hardly over 1 lin. wide in profile. Spatheoles very narrow, 
acute, scarious to submembranous, reddish, l|-f in. long; peduncles 
6-3 lin. long, finely filiform, pubescent upwards. Racemes 2-nate, 
hardly diverging, erect, f to 1 in. long, moderately villous, reddish- 
brown, one subsessile, the other with a distinct bare base; bases 
rather stout upwards, or that of the upper raceme linear and up to 
1 lin. long, minutely pubescent, their tips cupular and denticulate, 
the adjacent pedicel of the subsessile raceme more or less swollen 
and hard, 1 lin. long, glabrous on the back ; fertile joints linear, 
If lin. long, pubescent on the back, very shortly ciliate below, long- 
ciliate towards the cupular tips (cilia up to 1 J lin. long), cupule rather 
conspicuous, membranous, dentate ; adjacent pedicels very similar. 
Homogamous or imperfect sessile spikelet 1 at the base of the sessile 
raceme, intermediate as to shape. Fertile spikelets linear in front view, 
more or less acuminate, 2f-3J lin. long, greenish, turning straw-colour 
or reddish, glabrous ; callus short, obtuse, shortly bearded. Glumes 
unequal, chartaceous ; lower obscurely 2-dentate, deeply grooved 
below the middle with a callous gibbosity at the base, shallowly 
concave to flat upwards, keels acute, scabrid, intracarinal nerves 0, 
inflexed margins narrow ; upper glume shorter, linear-lanceolate 
in profile, acute, hardly curved on the back, 1 -nerved, ciliate. Lower 
floret reduced to a narrow oblong hyaline almost nerveless ciliate 
valve, slightly shorter than the upper glume. Upper floret : 
valve narrow, linear, 2-fid to over one-third, 2 lin. long, subchartaceous 
