CYPERUS. | CYPERACE. 323 
Spikelets in twice compound umbels. 
Nut globose, white. ‘ . 3. C. flavidus. 
Nut triquetrous, browns. > 4. C. amabilis. 
Perennials. 
Spikelets white or pale straw-colour in. 
heads . 7 : : ‘ . 5. Cy niveus. 
Spikelets in compound umbels, leaves 
broad . : - . 6. C. diffusus. 
Il. Spikelets spicate (sometimes very shortly) 
rarely subracemose. 
A, Annuals. 
Spikelets very shortly spicate. 
Spikelets 3-3 in. long ; stamens 3. 7. C, compressus, 
Spikelets usually 4-} in. long ; 
Stamenl . A ‘ 8. C. aristatus. 
Spikelets in an elongate subrace- 
mose spike . : ; . 9 C. Irie. 
B. Perennials. 
Inflorescence a large compound 
umbel. 
Bracts (the longest) usually much 
exceeding the inflorescence. 
1. Spikelets 4 in. long or less 
Rachis of the spikes glab- 
rous. 
(a) Spikelets numerous 
in an_ elongate 
spike. 
Rachilla of spike- 
lets narrowly 
winged . . 10. C. eleusinoides. 
Rachilla of spike- 
lets conspiculously 
winged. 
Wings of rachilla 
persistent. 
Spikes digitate 11. C. radiatus, 
