322 CYPERACEA. [ CYPERUS. 
Style-base passing gradually into the 
nut, sometimes deciduous and leaving 
a small apiculus. 
Bristles linear, filiform orO . - 10. Scirpus. 
Bristles 2-seriate, the inner scale-like 
or 0 , 3 . ll. Fuirena. 
Bristles 6, cut into narrow segments 12. Eriophorum. 
Bristles 2, scale-like enclosing the 
nut ; ; . 13. Lipocarpha. 
Flowers 1-sexual, nut bony usually white or 
pale, polished ; ; 2 : . 14, Scleria. 
Nut enclosed inautricle . ; J . 15. Carez. 
1. CYPERUS, Linn.; Fl. Brit. Ind. vi, 597. 
Perennial or annual herbs, tufted or with creeping root-stocks., 
Leaves usually only at the base of the stem, occasionally reduced 
to sheaths. Spikelets in solitary globose or umbellate heads or 
spikes, bracts one or more, leafy, immediately below the inflores- 
cence, bracteoles usually similar but smaller below the secondary 
divisions of the inflorescence. The spikelets composed of several 
or many distichous glumes the two lowest being empty and differ- 
ing in size and shape from the rest which are equal and deciduous 
from below upwards, the uppermost 1-3 sterile or empty. Hypo- 
gynous bristles 0. Stamens 1-3; anthers linear or oblong, some- 
times apiculate or crested. Ovary usually trigonous; style short 
or long or 0, branches 3. Nut trigonous, rarely compressed or 
globose. Species about 300 in all warm and temperate regions. 
The following key cannot be used for depauperated specimens 
which can only be identified by comparison with normally deve- 
loped ones. 
I. Spikelets digitate or clustered not spicate 
or racemose. 
Annuals, slender or cespitose. 
Flowering glumes mucronate . - 1. C. uncinatus. 
Flowering glumes obtuse. 
Spikelets in dense compact heads . 2. C. difformis. 
