l62 FLORA. 



often compound; primary rayg i 6 cm. long; spikelets numerous, usually densely 

 clustered, linear, acute, 8 20 cm. long, 2 3 mm. wide, flat, many-flowered, spread, 

 ing; scales oblong, obtuse, thin, dull, yellowish -brown; stamens 3; style 2-cleft, 

 little exserted; achene obovate, lenticular, black, mucronate, not shining, marly 



as long as the stales and often persistent on the radii- after these have fallen 

 away. In wet or moist sandy soil, Ya. to Fla. and La. Aug.-Oct. 



7. Cyperus inflexus MuhL AWNED CYPERUS. (I. F. f. 549.) Annual; 

 culms slender or almost filiform, tufted, about equalled by the leaves. Leaves 

 2 mm. wide or less, those of the involucre 23. exceeding the umbel; umbel sc>sile. 

 capitate, or 1 3-rayed; spikelets linear-oblong, 6- 10- flowered, 4-6 mm. long; scales 

 light brown, lanceolate, rather firm, strongly several-nerved, tapering into a long, 

 recurved awn, falling from the rachis at maturity; stamen 1; style 3-cleft; rachis 

 winged, the wings persistent; achene 3 -angled, brown, dull, narrowly obovoid or 

 oblong, obtuse, mucronulate. In wet, sandy soil, Vt. to the N. W. Terr, and Ore., 

 south to Fla., Tex., Cal. and Mex. Fragrant in drying. July-Sept. 



8. Cyperus compressus L. Flat Cyperus. (I. F. f. 550.) Annual; culms 

 slender, erect or reclining, smooth, 7-25 cm. long. Leaves light green, about 

 2 mm. wide, those of the involucre 2-3, the longer exceeding the spikelets; umbel 

 capitate or with 2-3 short rays; spikelets narrowly lanceolate, acute, 8-20 mm. 

 long, 3-4 mm. wide, very flat, many-flowered; scales light green with a yellow 

 band on each side, ovate, acuminate, firm, keeled, several-nerved, falling away 

 from the narrowly-winged rachis at maturity; stamens 3; style 3-cleft; achene 

 sharply 3-angled, obovoid, obtuse, dull, brown, about one-third as long as the 

 scale. In fields, Md. to Fla., west to Mo. and Tex. Also in trop. Amer. and the 

 Old World. Aug.-Oct. 



9. Cyperus Schweinitzii Torr. Schweinttz's Cyperus. (I. F. f. 551.) 

 Perennial by the thickened corm-like bases of the culms; culms rather slender, 

 rough, at least above, 0.3-0.8 m. tall. Leaves 2-5 mm. wide, rough-margined, 

 those of the involucre 3-7, erect; umb* I simple, 3-9-rayed. the rays erect, 

 sometimes 10 cm. long; spikelets flat, in rather loose ovoid spikes, linear 

 oblong, 6-12-flowercd, 8-16 mm. long; scales convex, light green, ovate, acute or 

 acuminate, 9-13-nerved, falling away from the rachis at maturity; stamens 3; 

 style 3-cleft; achene 3-angled, oblong, brown, acute at each end, -nearly as long as 

 the sccde. In sandy soil, especially along lakes and streams, W. N. V. and S. 

 Out. to the X. W. Terr., Minn., Iowa and Kans. Aug.-Oct. 



10. Cyperus pseudovegetus Steud. Marsh Cyperus. (I. F. f. 552.) Per- 

 ennial by thickened tuber-like joints of the rootstocks, culm rather stout. 0.3-1.3 m. 

 high, often equalled by the leaves. Leaves 3-4 mm. wide, smooth, nodulose, 

 the midvein prominent; leaves of the involucre 4-6, spreading; umbel several- 

 rayed, compound; spikelets ovate, flat, many-flowered, light green, densely capi- 

 tate, 4-6 mm. long; scales keeled, conduplicate, I -nerved, curved, acute, longer 

 than the linear 3-angled slightly stalked achene; stamen I; style 3-cleft. In 

 marshes, Del. to Fla., west to Kans. and Tex. July-Sept. 



11. Cyperus acuminatus Torr. & Hook. Short-pointed Cvperus. (I. F. f. 

 553.) Annual; culms very slender, tufted, 7-40 cm. tall. Leaves light green, 

 usually less than 2 mm. wide, those of the involucre much elongated; umbel 1-4- 

 rayed, simple; rays short; spikelets flat, ovate-oblong, obtuse, 4-8 mm. long, many- 

 flow red. densely capitate; scales oblong, pale-green, 3-nerved, coarsely cellular,! 

 Conduplicate, With a short sharp more or less recurved tip; stamen 1; styal 

 3-cleft; achene sharply 3-angled. gray, oblong, narrowed at each end. about one-haU f 

 as long as the scale. In moist soil, 111. to La., west to Iowa. Kans., Ore., lex., 

 and Cal. July-Oct. 



12. Cyperus fuscus L. BROWN C\t>krus. (I. F. f. 554.) Annual; culmf, 

 tufted, 15-40 cm. high, longer than or equalled by the leaves. Leaves rather dark 

 green, about 2 mm. 'wide, those of the involucre 4-6; umbel several-rayed; -pike 

 let- Linear, 4-14 mm. long, less than 2 mm. wide, many-flowered, acute; scaled 

 ovate, subacute, becoming dark brown, faintly about 3-nerved. separating from th<| 

 narrowly winged rachis as they mature; stamens 2 or 3; style 3-cleft; aihemj 

 3-angled, Oblong, pointed at each end. nearly as Long as the scale. Revere beach:' 



Mass., and New London, Conn. Adventive or fugitive from Europe. Abo u| 

 balh^t about the eastern seaports. July-Sept. 



