Ccelorhachis.'] clvii. gramine^e (Stapf). 
81 
long. Grain oblong, dorsally compressed, 1 lin. long, biconvex ; 
scutellum elliptic, half the length of the grain, hihim punctiform, 
basal. Pedicelled spikelet similar to the sessile, but smaller, with 
a winged keel to the upper glume and obscure nerves to the valves 
and valvule. Upper floret $ . 
Upper Guinea. French Guinea : Middle Niger ; Bammako, Soknafi Falls, 
Chevalier , 232 ! 
Lower Guinea. Angola : Benguella : Fte Princeza Amelia, in humid situa- 
tions by the Cubango River, Gossweiler, 3314 ! Cunsango River near Lobo and 
Qualhunge, abundant along brooks, Gossweiler, 801 ! river side below Chibia, 
Pearson, 2721 ! 
21. RHYTACHNE, Desv. in Hamilt. Prodr. PI. Ind. Occ. 11. 
Spikelets 2-nate on the nodes of the more or less fragile rhachis 
of slender cylindric or somewhat compressed distichous slightly 
dorsiventral racemes terminating simple 1-noded culms, the pedi- 
celled barren, very much reduced or suppressed ; joints more or 
less clavate to sublinear and hollow upwards, forming with the 
posticously contiguous compressed more or less linear pedicels a 
receptacle for the reception of the sessile spikelet ; disarticulation 
of the joints at a right angle to the rhachis, their tips without an 
appendage. Sessile spikelets dorsally compressed with a very narrow 
transverse callus, fused with the adjacent joint and pedicel into a 
fine annular rim, the whole plexus falling together. Florets 2, 
lower rarely neuter, upper $ , awnless. Glumes equal, apart 
from occasional bristles ; lower coriaceous, convex on the back, 
usually transversely rugose, very faintly nerved ; upper mem- 
branous, hyaline, 3-5-nerved with or without a terminal bristle-like 
awn. Valves linear-lanceolate to oblong, hyaline, 1- or 2- (rarely 
3-) nerved. Valvules hyaline, shorter than the valves to very short, 
delicately 2-nerved to nerveless. Lodicules 2, cuneate. Stamens 3. 
Stigmas short, suberect. Grain unknown. Pedicelled spikelets 
rudimentary, often represented by a bristle or point or quite sup- 
pressed. — Perennial or annual grasses with very slender l-t-noded 
culms ; blades usually long and setaceous ; ligules very short, 
membranous ; racemes rigid or flexuous ; the lower glumes spreading 
obliquely during flowering. 
Species 7, in Tropical Africa and Madagascar. 
Perennial ; culms and leaf-shoots in compact tufts. 
Spikelets 4-4 J lin. long, in cylindric spike -like 
racemes, up to over 1 lin. in diameter ; lower 
glume not rugose on the rounded back : a 
somewhat robust grass with linear leaf- blades, 
4-5 lin. wide 
■ flLi# 
l , JjL ' 
t u 
1. R. robusta. 
Spikelets not over 2\ lin. long, in slender or very 
slender racemes ; lower glume usually trans- 
versely rugose : slender grasses with more or 
less setaceous leaf-blades. 
Raceme very fragile. Lower glume transversely 
rugose, 2-2|- lin. long. 
FL. TROP. AFR. VOL. IX. 
G 
