CYPERACEAE. 



VOL. I. 



25. Cyperus ferax L. C. Richard. Coarse 

 Cyperus. Fig. 745, 



Cy fa-its fera.r L. C. Rich, Act. Soc. Hist. Nat. 

 Paris i : 106. 1792. 



Annual, closely related to the preceding 

 species, but with smooth-margined, shorter and 

 broader leaves, those of the involucre some- 

 times but little exceeding the inflorescence, the 

 scales of the spikelets less imbricated. Umbel 

 simple or somewhat compound, often compact, 

 the rays mostly short ; spikelets linear, sub- 

 terete, io-20-iiowered, 8"-i2" long, about i" 

 thick, falling away from the axis at maturity; 

 scales ovate-oblong, appressed, slightly or 

 scarcely imbricated, obtusish or acute, rather 

 firm, green and /-g-nerved on the back, yel- 

 lowish on the sides; stamens 3; style 3-cleft; 

 rachis broadly winged ; achene 3-angled, nar- 

 rowly obovoid, obtuse. 



In wet soil, Massachusetts to Florida. Cali- 

 fornia, and widely distributed in tropical America. 

 Aug.-Oct. 



26. Cyperus Engelmanni Steucl. Engelmann's 

 Cyperus. Fig. 746. 



Cyperus Engelmanni Steud. Syn. PI. Cyp. 47. 1855. 



Annual, culms slender, 6'-2^ tall. Leaves elongated, 

 2"-3" wide, flaccid, roughish on the margins, those of 

 the involucre 4-6, the longer exceeding the umbel ; 

 umbel often compound, the raylets very short; spikelets 

 often densely crowded, very narrowly linear, subterete, 

 6"- 1 2" long, 5-i5-flowered ; rachis narrowly winged; 

 scales greenish-brown, oblong, obtuse, thin, faintly 

 3~5-nerved on the back, distant, the successive ones on 

 each side of the spikelet separated by a space of about 

 one-half their length; stamens 3; style 3-cleft; achene 

 linear-oblong, 3-angled, two-thirds as long as the scale. 



In wet soil, Massachusetts to southe r n Ontario and Wis- 

 consin, south to New Jersey and Missouri. Aug.-Oct. 



27. Cyperus strigosus L. Straw-colored 

 Cyperus. Fig. 747. 



Cyperus strigosus L. Sp. PI. 47. 1753. 



C. strigosus capitatus Boeckl. Linnaea 36 : 347. 



1869-70. 

 C. strigosus compositits Britton, Bull. Torr. Club 



13: 212. 1886. 



C. strigosus robustior Kunth, Enum. 2 : 88. 1837. 

 Perennial by basal tuber-like corms, culm 

 rather stout, i-3 tall. Leaves somewhat 

 rough-margined, 2"-3" wide, the longer ones 

 of the involucre much exceeding the umbel ; 

 umbel several-rayed, compound or nearly 

 simple, some of the primary rays often 4'-6' 

 long, their sheaths terminating in 2 bristles; 

 involucels setaceous ; heads oblong to sub- 

 globose ; spikelets flat, linear, 3"-i2" long, i" 

 wide or less, /-25-flowered, separating from 

 the axis at maturity ; scales straw-colored, 

 oblong-lanceolate, subacute, strongly several- 

 nerved, appressed, or at length somewhat 

 spreading; stamens 3; style 3-cleft; achene 

 linear-oblong, 3-angled, acute, about one-third 

 as long as the scale. 



In moist meadows, swamps or along streams, 



Maine and Ontario to Minnesota, Florida and Texas. Lank galingale. Nut-grass. Ground-moss. 



Contains several races, differing in size, length of rays, length and width of spikelets. Aug.-Oct. 



