176 



FLORA. 



Bristles flexuous, twice as long as the achene; leaves 4-6 mm. wide. 



25. S. polyphyllus. 

 Spikelets cylindric, 6-10 mm. long. 26. S. Peckii. 



Bristles smooth or sightly pubescent; umbel mostly decompound. 

 Bristles shorter than or scarcely exceeding the scales. 



Bristles about as long as the achene ; scales subacute. 



27. S. divaricatus. 

 Bristles much longer than the achene ; scales mucronate. 



28. S. tin eat us. 

 Bristles much exserted beyond the scales when mature. 29. S. cyperinus. 



1. Scirpus nanus Spreng. Dwarf Club-rush. (I. F. f. 609.) Annual; 

 roots fibrous; culms filiform, flattened, grooved, tufted, erect or ascending, 2-5 cm. 

 high, bearing a scarious bladeless sheath near the base. Spikelet solitary, terminal, 

 ovoid-oblong, rather acute, 3-8 flowered, 2-3 mm. long, not subtended by a bract; 

 scales ovate or lanceolate, pale green, the lower obtuse, the upper subacute; bristles 

 about 6, downwardly barbed, longer than the achene; stamens 3; style 3-cleft; 

 achene oblong, 3 -angled, pale, pointed at each end, smooth. Muddy places in 

 salt marshes, Cape Breton Id. to Fla. and Tex., and about salt springs in N. Y. and 

 Mich. Also on the Pacific Coast of N. Am. and on the coasts of Europe. July-Sept. 



2. Scirpus paucinorus Lightf. Few-flowered Club-rush. (I. F. f. 610.) 

 Perennial by filiform rootstocks; culms very slender, little tufted, 3 -angled, grooved, 

 leafless, 7-25 cm. tall, the upper sheath truncate. Spikelet terminal, solitary, not 

 subtended by an involucral bract, oblong, compressed, 4-10 flowered, 4-6 mm. long, 

 nearly 2 mm. wide; scales brown with lighter margins and midvein, lanceolate, 

 acuminate; bristles 2-6, hispid, as long as the achene or longer; stamens 3; style 

 3-cleft; achene obovoid-oblong, gray, rather abruptly beaked, its surface finely 

 reticulated. In wet soil, Anticosti and Ont. to Me., W. N. Y., Minn, and Br. Col., 

 south in the Rocky Mountains to Colo. Also in northern Europe. July-Oct. 



3. Scirpus caespitdsus L. Tufted Club-rush. (I. F. f. 611.) Perennial; 

 culms smooth, terete, densely tufted, light green, erect or ascending, almost filiform, 

 wiry, 10-40 cm. long. Basal sheaths numerous, membranous, imbricated, acumi- 

 nate, the upper one bearing a short very narrow blade; spikelet solitary, terminal, 

 few-flowered, ovoid-oblong, about 4 mm. long, subtended by a subulate involucral 

 leaf of about its own length; scales yellowish-brown, ovate, obtuse or subacute, 

 deciduous; bristles 6, smooth, longer than the achene; stamens 3; style 3-cleft; 

 achene oblong, smooth, 3 -angled, brown, acute. In bogs and on moist rocks, 

 Greenl. to Alaska, south to the mountains of N. E., the Adirondacks, W. N. Y., 111., 

 Minn, and Br. Col., in the Rocky Mountains to Colo., and on the higher summits of 

 the southern Alleghenies. Also in Europe and Asia. June-Aug. 



4. Scirpus Clmtoni A. Gray. Clinton's Club-rush. (I. F. f. 612). 

 Perennial; culms tufted, triangular, very slender, erect, 10-40 cm. tall, roughish 

 on the angles. Lower sheaths imbricated, one or more of them bearing short subu- 

 late blades, the upper one bearing a flat, narrowly linear blade shorter than the 

 culm; spikelet solitary, terminal, ovoid, few-flowered, 3-4 mm. long, subtended by 

 a subulate involucral bract; scales ovate, pale brown, acute; bristles 3-6, filiform, 

 upwardly barbed, as long as the achene or longer; style 3-cleft; achene oblong, 

 brown, sharply 3-angled, smooth, obtuse. In dry fields and thickets, N. B. to W. 

 N. Y. and Mich., south to N. C. Local. June-Aug. 



5. Scirpus planifdlius Muhl. Wood Club-rusii. (I. F. f. 613.) Perennial; 

 culms triangular, slender, tufted, rather weak, roughish on the angles, 15-40 cm. 

 tall. Lower sheaths bearing short subulate blades, the upper with a flat narrowly 

 linear rough-margined leaf about as long as the culm; spikelet solitary, terminal, 

 ovoid-oblong, acute, several-flowered, subtended by a short involucral bract; scales 

 ovate-lanceolate, yellowish-brown with a green midvein, which is extended beyond 

 the acute apex into a sharp cusp; bristles 4-6, upwardly barbed, about equalling 

 the achene; stamens 3; style 3-cleft, pubescent; achene oblong, 3-angled, smooth, 

 light brown, rather obtuse. In woods and thickets, Mass. to Del., W. N. Y. and Mo. 

 May-July. 



6. Scirpus subterminalis Torr. WatER Club-rush. (I. F. f. 614.) 

 Perennial (?). aquatic, culms slender, terete, nodulose, 0.3-1 m. long. Leaves 

 slender, channeled, 15 50 cm. long, 0.5 1 mm. wide; spikelet solitary, terminal, 



