2 4 2 



CYPERACEAE. 



20. Cyperus speciosus Vahl. Michaux's Cyperus. (Fig. 562.) 



Cyperus speciosus Vahl, Enum. 2: 364. 1806. 

 Cyperus Michauxianus Schultes, t Mant. 2: 

 123. 1824. 



Annual, culms stout or slender, usually 

 tufted, 5'-2 tall, reddish toward the 

 base. Leaves rough-margined, iX // - 2 X // 

 wide, shorter than or equalling the culm, 

 the midvein prominent; leaves of the in- 

 volucre much exceeding the umbel; um- 

 bel compound or nearly simple, 3~7-rayed, 

 the primary rays I'-sJ^' long; involucels 

 narrow; spikelets subterete, very nar- 

 rowly linear, loosely or densely clustered, 

 4 // -i2 // long, less than i x/ thick, 10-30- 

 flowered, falling away from the axis at 

 maturity; scales dull brown, thin, ap- 

 pressed, densely imbricated, ovate, ob- 

 tuse, faintly 3~5-nerved on the back; 

 rachis-wings broad, clasping the achene, 

 persistent; stamens 3; style 3-cleft, slight- 

 ly exserted; achene pale, 3-angled, about 

 one-half as long as the scale, its super- 

 ficial cells nearly quadrate. 



In marshes, Rhode Island to Ohio and Minnesota, south to Florida, Texas and California. 

 July-Sept. 



Cyperus speciosus ferruginescens (Boeckl. ) Britton, Mem. Torr. Club, 5: 61. 1894. 

 Cyperus ferruginescens Boeckl. Linnaea, 36: 396. 1869-70. 



Scales spreading or slightly recurved, reddish. Missouri to Texas and New Mexico. 



Cyperus speciosus parvus (Boeckl.) Britton, Bull. Torr. Club, 13: 214. 1886. 

 Cyperus parvus Boeckl. Linnaea, 36: 397. 1869-70. 



Culm i '-3' high; umbel very simple, generally of but a single cluster of short spikelets. Mis- 

 souri to New Mexico. 



21. Cyperus ferox Vahl. Coarse Cyperus. (Fig. 563.) 



Cyperus ferox Vahl, Enum. 2: 357. 1806. 



Annual, closely related to the preced- 

 ing species, but with smooth-margined, 

 shorter and broader leaves, those of the 

 involucre sometimes but little exceeding 

 the inflorescence. Umbel simple or some- 

 what compound, often compact, the rays 

 mostly short; spikelets linear, subterete, 

 io-2o-flowered, 8 // -i2 // long, about i" 

 thick, falling away from the axis at 

 maturity; scales ovate-oblong, appressed, 

 imbricated, obtuse, rather firm, green and 

 7-9 nerved on the back, yellowish on the 

 sides; stamens 3; style 3-cleft; rachis 

 broadly winged; achene 3-angled, nar- 

 rowly obovoid, obtuse. 



In wet soil, Missouri to California and 

 widely distributed in tropical America, 

 Aug. -Oct. 



