84 CYPERACE^. 



Flowers perfect (the stamens and pistils in the axil of the same bractlet). 



Splkelets flattened, the braetlets arranged in 2 opposite rows 



1. Cypebus. 

 Spikelets cylindrical, the braetlets arranged around the axis in several rows. 

 Style enlarged at base, 

 Forming a persistent tubercle jointed on the apex of the achene; spikelet 



solitary, terminal upon a leafless bractless scape . . 2. Eleocharis. 

 Wholly deciduous at maturity; spiiielets in an involuerate umbel 



3. FlMBEISTYLIS. 



Style not enlarged at base, deciduous or only the base persistent 

 Stamens mostly 3; spikelets solitary or clustered or in a compound 



umbel 4. SciEPXis. 



Stamens 1 to 3; bristles (perianib-hairs) numerous, long exserted and 



silky in fruit 5. Eeiophokum. 



Flowers monoecious or dicecious, usually in separate spikelets; pistil and achene 

 enclosed in an inflated sac-like bractlet (perigynium) . 6. Carex. 



1. CYPERUS L. Galingale. 

 Annuals or perennials. Stems triangular, leafy at the base, the 

 inflorescence subtended by 1 or more conspicuous, leafy bracts. 

 Spikelets solitary or clustered on the unequal rays of an umbel with 

 the central spikelet or cluster always sessile, or the whole contracted 

 into a dense head. Braetlets concave and more or less carinate, 

 arranged in 2 ranks in a flattened spikelet. Bristles in the flower 

 none. (Kuperos, an old Greek name applied by Herodotus to an 

 aromatic plant used by the Scythians for embalming.) 



Style 2-eleft; achene lenticular; racbilla narrow, not winged . 1. C. diandrus 



var. castaneus. 

 Style 3-cleft; achene triangular, 

 kachilla not winged, naked or nearly so. 

 Stems }^ to 6 inr high ... . . 2. C. aristatns. 



Stems over 12 in. liigh 3. C serrulatus. 



Rachilla clothed with the persistent, decurrent wings of the braetlets. 



4. C. erythrorhisos. 



1. C. diandrus Torr. var. castaneus Torr. Described as an 

 annual with stems J to 2 ft. high, slender, triangular; leaves elongate, 



1 line or less wide; involucral bracts 2 to 3, foliaceous; spikelets 

 linear-oblong, acute, 3 to 6 lines long; rachilla not winged; braetlets 

 brown, 1 to IJ lines long; stamens 2 to 3; style 2-cleft to the middle; 

 achene lenticular. 



"Swamps near San Prancisco, Bolaiider^ and in the valley of the 

 Sacramento, Pickering." 



2. C. aristatus Kottb. Annual; stems J to 6 in. high, barely 

 exceeding the leaves; leaves \ line or less wide; involucral bracts 

 foliaceous, J to 2 in. long; rays few, \ tol in. long; spikelets sessile, 

 densely clustered, \\ to 3 lines long, flattened; rachilla not winged; 

 braetlets with strongly recurved setaceous tips, striate, chestnut-brown 

 or greenish, 1 line long; style 3-cleft; achene triangular. 



Chico, Ore.e?!!'; Jackson, Hansett; perhaps not . occurring within 

 our limits. June. 



3. C. serrulatus Wats. Perennialf?); stems 1 J ft. or more high, 

 stout, triangular; involucral bracts 6 to 8, foliaceous, 3 to 18 in. long, 



2 to 3J lines wide, flat (or conduplicate ?)•; inflorescence irregularly 

 umbellate, with unequal rays; spikelets numerous, in dense umbels, 



