216 
CLVII. GRAMINEiB (Stapf). 
[. Andropogon . 
Mouth of leaf-sheaths forming rounded shoulders or 
only slightly produced and adnate to the short 
(rarely much over 1 lin. long) ligule. 
Spikelets 2^-3 lin. long ; joints and pedicels 
shortly ciliate ; awns very slender, up to 4-6 lin. 
long 41. A. gabonensis. 
Spikelets 3-4 lin. long ; joints and pedicels 
villously-ciliat-e on one or both sides ; awns 
usually 9-15 lin. long 42. A. gay anus. 
Leaf -blades very large (to over 2 ft. by 14 in.), usually 
broad at the base and gradually passing into the 
sheath, very firm and rigid ; joints and pedicels [ lus . 
linear 43. A. macro-phyl- 
1. A. amethystinus, Steud. Syn. PI. Glum. i. 371. Perennial, 
compactly csespitose, 1 to over 1|- ft. high. Culms simple, slender, 
erect, 1-noded, terete, glabrous, smooth, the internodes grooved 
downwards. Leaf-sheaths terete, tight, glabrous, firm, the lower 
up to 3 in. long, more or less persistent ; ligules oblong to oblong- 
lanceolate, up to 2| lin. long, decurrent on the sheath, membranous, 
glabrous ; blades very narrowly linear, tapering to a fine point, up 
to over 1 ft. long, J-f lin. wide, rigid or slightly flexuous, flat or 
revolute along the margins, glabrous, smooth apart from the scabrid 
margins ; midrib relatively stout, whitish, prominent below ; 
lateral nerves about 3 on each side, very fine and close. Peduncles 
filiform, glabrous or more or less hairy towards the tips, to over 
1 ft. long. Eacemes 2-nate, 2-3 in. long, one subsessile, the other 
(rarely both) with a short more or less hairy base, olive-green 
to dull violet ; joints linear, l|--2 lin. long, shortly and densely 
ciliate on both sides, tips truncate ; pedicels very similar if not 
slightly more slender. Sessile spikelets linear-lanceolate, 3-3| 
lin. long ; callus obtuse, shortly and densely bearded. Glumes 
subequal, lower chartaceous, minutely and more or less unequally 
2- denticulate, flat or very shallowly grooved downwards on the 
back, glabrous or sparingly hairy, keels not or obscurely winged, 
wings like the indexed margins equal on both sides or nearly so ; 
intracarinal nerves 5-7, prominent, evenly distributed, slightly rough ; 
upper glume slightly shorter, submembranous, narrowly boat-shaped, 
3- nerved, ciliate, with a bristle up to 3 lin. long from a minute terminal 
notch. Lower floret reduced to a hyaline oblong obtuse 2-nerved 
ciliate valve 3 lin. long. Upper floret ^ : valve oblong, over 2| lin. 
long, 2-fid to one-third from the base with narrow linear lobes ; 
awn slender, 5-8 lin. long, kneed at and twisted below the middle ; 
valvule 0. Anthers If lin. long. Pedicelled spikelet $ or neuter, 
lanceolate-oblong, acuminate, up to 3 lin. long, glabrous or sparingly 
hairy ; lower glume thinly chartaceous, unequally 2-dentate, with 
a short bristle from between the teeth ; intracarinal nerves 7-11 ; 
upper glume very acute, sometimes produced into a mucro or short 
bristle, up to 1§ lin, long, ciliate ; valves of both florets if present 
