CYPERACEAE 
Culm aphyllopodic and but little fibrillose at base: 
b wanting: ligule conspicuous, longer than 
Culm hyllopodic and strongly o at ‘base: 
g. 
nate spike 
"unc conspicuously long- 
Be a c" less than half the length 
o 
Beak of perigynium as long as, or longer 
than the body. 
Body of perigynium P a 
spike 4-12 mm. 
Plants without jon slender s 
Plants with very long Sgt. stolons. 
Many Nus ed oo short and hidden among the base of 
staminate 
Achene. ao diiy triangular: scales strongly dark- 
margined: stolons E eee culm co- 
piously fibrillose at the 
Achene normally lenticillar c Qmm at most moder- 
ately dark-margined: stolons Tong, horizontal : 
culm little fibrillose at the base 
XII. TRIQUETRAE 
Foliage not pubescent: perigynium short-pubescent, 
many-ribbed, obovoid: achene very short stipitate: 
seales strongly several-ribbe 
Lower foliage soft pubescent: perigynium densely vil- 
lous above, many-nerved, elliptic- Pu E achene 
long stipitate: scales slenderly r 
XIII. PICTAE 
Represented by one species. 
XIV. DIGITATAE 
Represented by one species in our range 
XV. ALBAE 
Represented by one species in our range. 
x PANICEAE 
EePiEsn um with very short, often pent beak or beak- 
s : staminate scales strongly purplish-brown- 
Culm rupee: not strongly purplish-tinged at 
th a spreading by deep-seated slender white 
culm aphyllopodic, strongly mu usd at the 
ase, with interwoven stout rootstoc 
pene nion with prominent beak mm. ns stami- 
nate scales slightly yellowish- -brown-tinged. 
. XVII. LAXIFLORAE 
I. Staminate scales purplish. Bract-sheaths (usually) 
and base of the culm (always) strongly purplish. 
Bracts Mops . pistillate spikes closely flowered 
gyn n sharply triangular. 
- . wide: pistillate spikes 2-6- 
flowered on long Sca lary peduncles 
Leaf-blades 10- m. wide: pistillate spikes 4— 
12-flowered on stiff. pedun neles 
ir dno. pistillate spikes with perigy- 
i n y separate: perigynium obtusely 
tri ngula 
II. Stamina a never purplish.  Bract-sheaths 
not Dole -tinged, the base of the culm but 
ane so. 
Pabna s cutely triangular, 
base, hispidul ous. 
Leaf- ATE very smooth (except edges), the 
larger 12 mm. wide or more, those of the fer- 
tile culm much smaller than those of the 
steri 
short-tapering at 
40. 
Hy 
-1 
C 
6. 
e 
n 
C 
00 
C. communis. 
. C. pennsylvanica. 
. C. lucorum. 
C. varia. 
. C. physorhyncha. 
. C. nigro-marginata. 
. C. floridana. 
. C. validior. 
. C. dasycarpa. 
. C. picta. 
. C. Baltzellii. 
. €. eburnea. 
. C. Meadii. 
. C. biltmoreana. 
C. Chapman. 
C. plantaginea. 
. C. purpurifera. 
. C. platyphylla. 
. C. austro-caroliniana. 
