42 CYPERACEAE 



Spikes more than one. 



Perigynia not whlte-puncticulate. 



Eootstocks long-creeping, the culms arising singly or few together. 

 Perigynia not thin or wlng-marglned, the beak obliquely cut. 

 Culms not branching. 



Spikes densely aggregate into a globular-ovoid head, appearing 



like one spike. 6. Foetidae. 



Spikes distinct. 7. Divisae. 



Culms becoming decumbent and branching. 8. Chobdorbhiz.\e. 

 Perigynia thin or wing-margined, the bccik bidentate. 



9. Ahenahiae. 

 Bootstock not long-creeping, the culms densely cespitose. 

 Spikes androgynous. 



Perigynia abruptly contracted into the beak. 



Spikes few (ten or less) ; perigynia green or tinged with reddish 

 brown. 10. Mtjhl,enbergianae. 



^ikes numerous; perigynia yellowish or brownish. 



Perigynia yellowish; opaque part of leaf-she ath t ransversely 



rugulose. 11. Mtjlttflokae. 



Perigynia brownish; opaque part of leaf-sheath not trans- 

 versely rugulose. 12. Panicitlatae. 

 Perigynia tapering into the beak. 13. Stenorhtnchae. 

 Spikes gynaecandrous or pistillate or rarely staminate. 

 Perigynia at most thin-edged. 



Perigynia spreading at maturity. 14. Stellulatab 



Perigynia appressed. 15. Dewetanae. 



Perigynia narrowly to broadly wing-margined. 



16. OVAiES. 

 Peiigynia white-pimcticulate. 17. Canescentes. 



Achenes triangular or lenticular; if lenticular, lower lateral spikes conspicuously 

 peduncled, or terminal spike staminate and lateral spikes elongated. 

 Achenes strongly constricted at base, rounded at apex. 18. Phtli>ostachtae. 



Achenes not strongly constricted at base, pointed at apex. 



Spike one; perigynia rounded and beakless at apex. 19. Polttrichoideae. 

 Spikes one or more; when one, perigynia not both rounded and beakless at 

 the apex. 

 Perigynia both coriaceous and shining, the beak obUquely cut. 

 Spike solitary. 20. Obtusatae. 



Spikes several. 21. Nitidae. 



Perigjmia not both coriaceous and shining. 



Spike one; perigynia triangular, glabrous, not reflexed or flattened. 

 Perigynia prominently beaked, finely many-nerved. 



22. EUPESTRES. 



Perigynia nearly beakless, 2-keeled but otherwise nerveless. 



23. FIRMICDLMES. 



Spikes one to many; when one, perigynia difleriag from above. 



Perigynia closely envelopiog the acheue, strongly tapering at base, 

 pubescent or puberulent; bracts sheathless or nearly so. 

 Spike normally one. 



Spikes androgynous; leaf-blades very narrow. 



24. FlUFOLIAE. 

 Spikes dioecious. 25. Scihpinae. 



Spikes two or more. 26. MONTANAE. 



Perigynia not as above; or if so, bracts strongly sheathing. 

 Lowest bract long-sheathing, its blades rudimentary. 

 Leaf-blades fiat; perigynia puberulent or pubescent. 



27. DiGITATAE. 



l.ieaf-blades filiform; perigynia glabrous. 



28. Albae. 



Lowest bract sheathless or long-sheathing; if long-sheathing, its 

 blade well-developed. 

 Lowest bract strongly sheathing; perigynia never strongly 

 bidentate with stifl! teeth. 

 Achenes lenticular; stigmas two. 29. Bicolokes. 

 Achenes triangular; stigmas three. 

 Scales not dark-tinged. 



Pistillate spikes short-oblong to linear, erect. 



Perigynia tapering at base, triangular, closely 

 enveloping the achenes. 

 Rootstock long-creeping. 



30. Paniceae. 

 Rootstock not long-creeping. 



31. IjAXlFLORAB. 



Perigynia rounded at base, suborbicular in 

 cross-section, loosely enveloping achenes. 



32. Grantilares. 

 Pistillate spikes elongate, linear to cyUndrlc, 



slender peduncled, the lower drooping. 

 Culms strongly reddish tinged at base, aphyl- 



lopodic. 33. Debiles. 



Culms not strongly reddish tinged at base. 



phyUopodlo. 



