Sedge Family 69 



vate, plano-convex, nearly \vhite or brown, narrowed above into 

 a short point, contracted at base, 1-1.25 mm. broad. (S. Tatora 

 Kunth.) 



With the last and apparently more common. Typical forms are readily 

 distinguished by the stouter and shorter strongly ciliate bristles, stouter 

 filaments, and smaller achene tapering at the apex. Intermediate forms, 

 apparently hybrids, are occasionally found. 



*-*- Inflorescence terminal; stem leafy. 



6. S. robustus Pursh. Perennial by large rootstocks ; steins 

 stout, sharply 3-angled with flat sides, smooth, 6-15 dm. high; 

 leaves equaling or exceeding the stem, smooth, 5-10 mm. wide, 

 midvein prominent; involucral leaves 2-4, elongated, erect, sim- 

 ilar to those of the stem, often 3 cm. long; spikelets in a dense, 

 often compound terminal cluster of 6-20, ovoid-oblong, obtuse or 

 subacute, 16-24 mm. long, 8-10 mm. broad; scales ovate, brown, 

 puberulent, lacerate or 2-toothed, midvein excurrent into an at 

 length reflexed awn ; bristles 1-6, shorter than the achenes, or 

 none; style 3-cleft; achene compressed, flat on the face, convex 

 or with a low ridge on the back, obovate-orbicular, dark brown, 

 shining, 3 mm. long. (S. maritimus of the Bot. Cal., not of L.) 



Common in marshes, especially in somewhat saline places. June-October. 



7. S. atrovirens Muhl. Perennial by slender rootstocks; 

 stems 3-angled, rather slender, leafy, 6-12 dm. high; leaves 

 elongated, nodulose, rough on the margins, 6-12 mm. wide, 1-2 

 usually exceeding the inflorescence; involucral leaves usually 

 several, unequal, the longer equaling or exceeding the rays; um- 

 bel 1-2-compound or rarely simple ; spikelets ovoid-oblong, acute, 

 densely capitate in 6's-20's at the ends of the rays or raylets ; 

 scales greenish-brown, oblong, acute, midvein excurrent ; bristles 

 usually 6, retrorsely barbed above, naked below, about equaling 

 the achene; style 3-cleft; achene oblong-obovoid, 3-angled, pale 

 brown, dull. 



Marshes in Los Angeles and Glendale, Davidson. 



8. S. microcarpus Presl. Perennial; stems 6-12 dm. high, 

 rather stout; leaves rough-margined, exceeding the stem; the 

 longer involucral leaves usually exceeding the inflorescence ; um- 

 bel 1-2-compound ; spikelets 3-25 together in capitate clusters at 

 the ends of usually spreading raylets, ovoid-oblong, 3-4 mm. long, 



