64 CYPERACEAE. 



ovoid, obtuse, 4-5 mm. high and 3 mm. thick; scales ovate, obtuse, 

 2 mm. long, brown with a green midvein; stamens 2; bristles 4-6, 

 obscurely toothed, equaling the achene or none; achenes broadly 

 obovoid, black and shining, tubercle flat and disk-like. 

 San Bernardino, Parish. 



2. E. palustris (L.) R. & S. Perennial by horizontal rootstocks; 

 stems stout, terete or nearly so, striate, 3-8 dm. high; basal sheaths 

 brown, rarely bearing a short blade, the upper one obliquely truncate; 

 spikelet ovoid-cylindric, 6-24 mm. long, 3-4 mm. broad, thicker 

 than the stem; scales ovate-oblong or ovate-lanceolate, purplish- 

 brown, with scarious margins and a green midvein; bristles usually 4, 

 slender, retrorsely barbed, longer than the achene, sometimes want- 

 ing; stamens 2-3; style 2-3-cleft; achene brownish or yellowish- 

 brown, smooth, obovate; tubercle conic-triangular, constricted at 

 the base, flattened, \-\ as long as the achene. 



Common in wet places along streams throughout our range. 

 May-August. 



3. E. acicularis (L.) R. & S. Perennial by filiform rootstocks 

 or stolons; stems filiform, tufted, obscurely 4-angled and grooved, 

 erect or spreading, 4-10 cm. long; sheaths truncate; spikelet com- 

 pressed, narrowly ovate, acute, 3-10-flowered, 3-6 mm. long, 1 mm. 

 broad; scales oblong, obtuse, thin, pale green, with a narrow band 

 of brown on each side of the midvein, deciduous, many usually 

 sterile; bristles 3-4, fugacious, shorter than the achene; stamens 3; 

 style 3-cleft; achene obovoid-oblong, obscurely 3-angled, with a rib 

 on each angle and 6-9 intermediate ones, connected by fine ridges; 

 tubercle conic, acute, \ as long as the achene. 



Frequent in moist places along streams and on borders of ponds. 

 April-June. 



4. E. montana (H. B. K.) R. & S. Perennial; stems slender, 

 sulcate, 15-45 cm. high, erect; basal sheaths brown; spike oblong 

 or sometimes ovate, 4-10 mm. long, rounded at the apex; scales 

 numerous, closely imbricated, ovate, very obtuse, brown with 

 green midvein, scarious margined; bristles 4-6, about equaling the 

 achene; style 3-cleft; achene obtusely 3-angled, oblong-obovate, 

 about 1 mm. long, greenish brown, smooth; tubercle broad at the 

 base and slightly constricted, deltoid, acute. (E. arenicola Torr.) 



Frequent on river bottoms and borders of marshes throughout 

 our range. 



5. E. rostellata Torr. Perennial; stems rather slender, com- 

 pressed, strongly sulcate, 3-8 dm. high; often reclining and rooting 

 at the apex; basal sheaths light colored, truncate; spike oblong, 

 6-10 mm. long; scales straw-colored or pale brown, ovate, obtuse, 

 carinate and rather firm, about 4 mm. long; bristles 6, exceeding the 

 achene; style 3-cleft; achene obovate, obtusely 3-angled, about 

 2 mm. long; tubercle not constricted at the base, pyramidal, about 

 1 mm. long. (£. rostellata occidentalis Wats.) 



Frequent in marshes and on river bottoms about Los Angeles 

 and San Bernardino. 



