56 POACEAE 
Leaf-blades glabrous or with occasional 
cilia, 8-16 mm. wide. 
Leaf- blades firm, tapering from the 
FE A base to summit: plants 
rather sto 
c blades. thin, tapering toward 
mmit: sheaths gla- 
Dione or abla ciliate: spikelets 
1.8-2 mm. lon 
Mea pubescent on one or both 
Le genes on both surfaces sparsely 
pilose with long hairs, rather thin. 
Leaf-blades s ely pubes scent 
both surfaces 
V. BIFID 
Racemes solitary or rarely 2 : spikelets subsessile, crowded. 
Racemes 2-5: spikelets long-pedicellate, loo 
VI. LAEVIA 
Plant erect or ascending, not stoloni dus Hor with leafy 
branches: spikelets PD LOOPS itary. 
E more or less flat 
Spikelets 1$5—15 as thick as broad: glume and 
sterile lemma firm 
Spikelets cd over 2.8 mm. long, longer than 
bro more than % as thick: panicle 
inuch exceeding the blades. 
Be dane glabrous or ciliate only. 
Leaf-sheaths and.blades pilose. 
Spikelets 3-3.2 mm. long, circular, not more 
uae l6 as Ede leaf- es equalling the 
base of the panicle or overtopping it. 
Spikelets "anttened. enin more than 14 as thick as 
broad, closely imbricate, often in pairs: 
pee and sterile lemma thin, the cells vis- 
ible: short sealy rootstocks present. 
paar ee or nearly so: spikelets 2.2-2.8 
Plant uds: spikelets 2.7-3.4 mm. 
Spikelets oe plano-convex: glume ud Sterile 
emma 
Leaves clustered toward the base 2 the s 
rarely o 15 cm. long, the upper half "oi 
the Stent appearing naked: stems Jess than 
or a usua lly 75 cm. or less, mostly as- 
Endin 
beare scai ed along the stem; some of the 
bla a at least, 20 cm. long, commonly much 
ger 
turity : leaf-blades flat, ee cm. wide, the 
i at 
Glume and sterile lemma slightly inflated and 
wrinkled, not rusty-tinged : racemes erect or 
ascending : leaf-blades firm, commonly folded, 
ahs ee not wider than the sheath, rarely as 
Plant decumbe ne a t base, rooting at the nodes, or sto- 
from the base), producing leafy branches: rachis 
20d mm. wide: spikelets in pairs, acute or sub- 
ute. (See also no. x 
Spikelets depressed plan m 
wide; leaf-sheaths keelod: "blades rarely ov er 5 mm. 
wide, "usually folded at base: racemes ascending or 
Spikelets turgidly plano-convex, 2 mm. or more wide: 
leaf-sheaths not keeled: blades more than 7 mm. 
wide (usually 10 mm. or more), flat. 
VII. DILATATA 
Panicle virgate, the usually numerous racemes suberect: 
spikelets scarcely over 2 mm. long. 
ped 
m 
18. 
19. 
Ny 
N 
bo 
3. 
24, 
bo 
Cc 
bo 
o 
t2 
N 
to 
(0 0) 
. P. propinquum. 
P. ciliatifolium. 
. P. pubescens. 
. P. supinum. 
P. a HIM 
P. bifidun 
. P. laeve. 
. P. longipilum. 
. P. circulare. 
. praecoa. 
P. lentiferum. 
. P. difforme. 
. P. giganteum. 
P. floridanum. 
. P. lividum. 
. P. pubiftorum. 
. P. Urvillei. 
