ctpeeacEjE. 555 



Spikeleis leveral, the terminal one mixed. 



. r Spikelets all sessile in a simple or branched, close or interrupted spike. Stigmas 2 . ^6 



" I Lower spikelets generally stalked. Stigmas 3 20 



f, I Terminal spikelet male at the base. Spike simple 7 



"iTerminalspikelet inaleat the top. Spike often branched or compound . . . .13 



fSpikelets forming a terminal spike without leafy bracts, or with only a smaU one to 

 7-^ the lowest spikelet ° 



l^Spikelets very distant, the lower ones each in the axU of a long leafy bract ... 12 



rSpilielets ovoid, close together. Fruits tapering to a point, erect or scarcely 

 8.; spreading f 



LSpikelets, at least the lower ones, at some distance from each other 10 



qf Fruits winged at the edges. Stems usually a foot high or more . . . . i.OcalC. 



(.Fruits not mnged. Stems usually S or 9 inches high .... %. Mare's-foot C. 



fFruits tapering to a point or beak considerably longer than the glume ... . 11 

 10-{ Fruits erect, ovate, with a minute point. Stems a foot or more. Spilcelets pale 



(_ green 9- Whitish C. 



rEipe spikelets nearly globular, with very spreading beaked fruits. Stem 6 or 8 inches. 



J^* .rs. jf= g^ Star-headed C. 



1 Eipe spikelets oblong, with rather spreading pointed fruits. Stem 1 to 2 feet. 



\^ 7. Elongated C. 



rAU the spikelets simple, sessile, and distant 10. Remote C. 



\%\ Lower spikelets branched or 2 or 3 together. Upper ones rather near together. 



[^ 11. Axillary C. 

 ,„(■ Stems tufted, without creeping rootstocks 1* 



\ Eootstock long and creeping 18 



f Spike compound or branched. Stems 1 to 4 feet (usually 2 to 3 feet) la 



14.1 Spike simple or the lower spikelets slightly compound. Stems not a foot or very 



l_ slender J° 



r Spike or panicle dark brown, rather loose. Fruits obtusely 3-angled . 12. Pamcled C. 

 15.! Spike cylindrical, often green, densely crowded. Fruits much flattened, with acute 



L, angles. Stem acutely triangular 13. Fox C. 



J - 5" Spikelets near together, in a terminal brown spilte about an iuch long . 14. Prickly C. 



(. Lower spikelets distant, all pale brown or green .• • •'^ 



f Fruiting spikelets globular, no male flowers at their base 14. Prickly C. 



ni Fruiting spikelets oblong, a few males at the base of some of them. Fruits flattened. 



i^ 11. Axillary C. 



rSpikelets rather large, ovoid, in a spike of 1 or 2 inches. Fruits with a very thin or 

 18-^ winged edge 15- Sand C. 



t^Spikelets short, in a spilie of about J inch. Fruit very convex, not winged . . .19 

 ,0 ("Spike ovoid, the spikelets distinct. Stem slender, erect .... 16. Divided C. 



(.Spike nearly globular, very dense. Stem short, curving downwards . 17. Curved C. 

 „f, f Spikelets short, erect 21 



(. Spikelets oblong or cylindrical, stalked and drooping 22 



r Spikelets at length rather distant, the lowest scarcely stalked. Fruit ovoid, obtuse. 



I ^ 22, Buxbaim's C. 



^■' i Spikelets close together, the lowest stalked. Fruit angular, shortly beaked. 



[_ 21. Alpine C. 



rSpikelets oblong, very black. Fruit triangular, with a short beak . . 23. Black C. 

 mi Soikelets cylindrical, green. Glumes and fruits with long subulate points. 



\ '^ 43. Cyperus-like C. 



Spilcelets several, one or more terminal ones wholly male. 



„,f Stigmas 2 24 



1 Stitrmas 3 27 



o , C Spikelets sraa'u, green, and distant, lower one branched or clustered . 11. Axillary C. 



(. Spikelets cylindrical or oblong, few, dark-brown or black 25 



-- f Fruits very convex or inflated 18- Russet C. 



^' \ Fruits nearly flat , -^ V • ?? 



„„ fGHumes mostly obtuse. Spikelets ^ to 2 mohes long 19. Tufted C. 



"(.Glumes mostly narrow and pointed. Female spikelets 3 inches or more. 20. Acute C. 

 „„ ( Bracts sheathing, without leafy tips. (Fruits obtuse, slightly downy) .... 28 

 ^' I Bracts, at least the lower ones, leafy, with or without sheaths 29 



f Stems shorter than the leaves. Female spikelets short, distant, half-included in the 



.,„! sheaths U. Dwarf C. 



^^\ Stems loneer than the leaves. Female spikelets near the top, bnear, spreading. 



|_ ^ 25. Fingered C. 



\ Fruits downy or hairy 30 



L Fruits glabrous 35 





