492 CYPERACE^;. (SEDGE FAMILY.) 



5. C. erythrorllizos, Muhl. Culm obtusely triangular (2 -3 high); 

 umbel compound, many-rayed ; involucre 4 - 5-leaved, very long ; involucels 

 bristle-form ; spikes very numerous, crowded in oblong-cylindrical nearly sessile 

 heads, spreading horizontally, linear, flatfish (%' long), bright chestnut-colored; 

 scales lanceolate, mucronulate. (V Alluvial banks, Penn. to Wisconsin? and 

 southward. August. Root fibrous, red. 



3. CYPEKUS PROPER. Style 3-cle/l : achenium triangular : spikes many- 

 fiowered, flat or almost terete ; only the lowest scale empty ; the joints of the axis 

 narrowly wing-margined or naked. 



* Roots annual, fibrous : no creeping rootstocks : culm triangular : spikes awl-shaped, 

 thread-shaped, or very narrowly linear, very numerous, crowded at the summit of the 

 rays of the simple or mostly compound ample and open umbel : involucre very long, 

 3 several-leaved : scales of the spike pointless ; the joints of the axis winged by a 

 pair of adherent scales : stamens 3. 



6. C. IVIicIiRiiviaiiiis, Schultes. Culm stout (lhigh); rays short; 

 spikes linear-thread-shaped, teretish when mature (!' ' long) ; the joints of its axis 

 short and winged with very broad scaly margins, which embrace the ovate triangular 

 achenium ; scales ovate, obtusish. Marshes, especially along the coast and 

 large rivers, S. New England to Wisconsin, and southward. Aug., Sept. 

 Flowers 6 - 20 in the spike, yellowish-brown. 



7. C. Ellgclimiimi, Steud. Culm -3 high; rays mostly short; 

 spikes filiform, almost terete (about ' long), somewhat remotely 5 - 9-fiowered, the 

 zigzag joints of the axis slender, narrowly wing-margined; achenium oblong-linear , 

 almost equalling the oblong or oval broadly scarious scale. (C. tenuior, Engelm. 

 mss. C. stenolepis, Tori'., probably, though the character does not accord : the 

 greenish keel or centre was perhaps taken for the whole scale, which is not nar- 

 row, so the name is inapplicable as well as doubtful. ) Low banks of streams, 

 Wisconsin, Illinois, Virginia ? and southward. Between the foregoing and 

 the next. The scales of the spike are so separated that their base is never 

 touched by the one next beneath on the same side. 



8. C. StrigosilS, L. Culm mostly stout, bulbous-thickened at the base 

 (l-3 high) ; some of the rays elongated, their sheaths 2-bristled ; spikes linear- 

 awl-shaped, but fiat, 8-1 5-flowered, very numerous, reflexed with age ; the 

 slender joints of the axis naiTowly wing-margined ; scales oblong-lanceolate, sev- 

 eral-nerved, much longer than the linear-oblong achenium. Var. SPECi6sus (C. 

 speciosus, Vahl? Torr.) is a rank state, with some of the partial umbels fur- 

 nished with a leafy involucel. Low or rich grounds ; common, especially 

 southward. July - Sept. Spikes greenish, turning straw-color, ' - 1' long. 



* * Roots annual, fibrous: stamen only 1 : culm slender, low (l'-12' high) : spikes 

 fiat, oblong-linear or ovate, crowded into heads on the few simple or compound rays : 

 involucre 2 - 3-leaved : scales of the spike with spreading points : joints of the axis 

 slightly or not at all margined. 



9. C. infleXllS, Muhl. Dwarf (l'-5^high); spikes oblong-linear, 7-13- 

 flowered, collected in 2-3 ovate heads (either sessile and clustered or short-pe 

 duncled) ; scales nerved, tapering into a long recurved point ,- achenium obovate, 

 obtuse. Sandy wet shores ; common. July - Sept. Sweet-seer ted iu drying. 



