CYPERACEJS. (SEDGE FAMILY.) 367 



3. S. Olneyi, Gray. Stem ^-wing-angled, with deeply excavated sides, 2 to 

 7 feet high, the upper sheath bearing a short triangular leaf or none : spikes 

 6 to 12, closely capitate, overtopped by the short involucral leaf: scales orbicu- 

 lar, smooth, raucronate-pointed : anthers with a vert/ short and blunt minutely 

 bearded tip. PI. Lindh. 30. Across the southern part of the continent and 

 nortlnvard along the Atlantic seaboard. 



*-* -M- Stem terete, very tall and stout, naked : sheaths at the base bearing a short 

 and imperfect leaf or none : spikes rusty or chestnut-brown, numerous and 

 clustered in a one-sided compound umbel-like panicle, the principal rays of which 

 mostly surpass the involucral leaf: scales with a salitnt midrib extending into 

 a mucronate point. 



4. S. lacustris, L. Stem 3 to 9 feet high, scales ciliate : akene pale and 

 dull, obovate with a narrowed base, usually overtopped by the 4 to 6 slender 

 downwardly barbed bristles. S. validus, Vahl. Common in fresh-water 

 ponds throughout the Atlantic States, and extending westward to the moun- 

 tains. 



Var. OCCidentalis, Watson. Scales often pubescent, especially on the 

 midvein, usually pale with fine brown lines : bristles not exserted : akene 

 broadly obovate, terminating abruptly in a rather short beak. Bot. Calif, 

 ii. 218. From Texas and Colorado to British Columbia and the Pacific 

 coast. Known as " Tule." 



*--- Spikes clustered in simple or mostly compound umbellate or cymose- 

 panicled clusters, many-Jlowered, terete : involucre of mostly several obvious 

 and flat leaves: stems tall, triangular, leafy. 



M. Spikes large : midrib of the scales extended beyond the mostly lacerate or 2-cleft 

 apex into a distinct awn. 



5. S. maritimus, L. Leaves flat, linear, as long as the stout stem (1 to 

 3 feet high), those of the involucre 1 to 4, very unequal : spikes few to several 

 in a sessile cluster, often also with 1 to 4 unequal rays : awns of the scale soon 

 recurved : akene obovate-orbicular, compressed, flai on one side, convex or obtuse- 

 angled on the other, minutely pointed, shining, longer than the bristles. In salt 

 marshes everywhere across the continent. 



6. S. fluviatilis, Gray. Stem stouter and taller : leaves flat, broadly 

 linear, the upper and those of the very long involucre much exceeding the 

 compound umbel : rays 5 to 9, elongated, recurved-spreading : scales less lacerate 

 and their awns less recurved : akene obovate, sharply and exactly triangular, 

 conspicuously pointed, dull, scarcely equalling the bristles. Borders of lakes 

 and streams from W. Vermont to Illinois and Wisconsin, and extending into 

 our range at its northeastern border. 



+* -w Spikes very numerous, small: scales mucronate-pointed or blunt: umbel-like 

 cymose panicle irregular, compound or decompound : stem tall and very leafy : 

 bristles very slender and often more or less tortuous and naked below. 



7. S. sylvaticus, L. Spikes lead-colored, 3 to 10 in a cluster at the end 

 of the mostly slender ultimate divisions of the open decompound panicle : scales 

 bluntish: bristles 6 and downwardly barbed throughout: akene angled on the 

 back, short-pointed : style 3-cleft. 



