OYPERACE^SE. (SEDGE FAMILY.) 867 



3. S. Olneyi, Gray. Stem 3-iving-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, mucronate-pointed : anthers with a very short and blunt minutely 

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

 northward along the Atlantic seaboard. 



*+ ** 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 wit h a salient midrib extending into 

 a mucronate point. 



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

 dull, obovate with » 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." 



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

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

 and fiat leaves : stems tall, triangular, leafy. 



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

 apex into a distinct awn. 



5. S. mar itimus, 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, fat 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. 



++ ++ 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. sylvatieus, 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 

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

 back short-pointed : style 3-cleft. 



