578 CYPERACE^E. (SEDGE FAMILY.) 



30. C. tenuifl6ra, Wahl. Spikes 3, few-flowered, closely approximated; 

 perigynia ovate-oblong, about the length of the broadly ovate scale. — Cold 

 swamps, N. New England to Wisconsin, and northward. (Eu.) 



31. C. can^SCens, L. (in part). Pale or glaucous; spikes 5-7 (about 

 12-20-flowered), the upper approximated, the rest distinct, the lowermost remote; 

 perigynia ovate, equalling the pointed scale. (C. curta, Good. C. Ricbardi, 

 Michx.) — Marshes and wet meadows . common, especially northward. (Eu.) 



Var. vitilis is a more slender and weak form, not glaucous, with smaller 

 and roundish 6 - 1 5-flowered spikes, the more pointed perigynia spreading (and 

 often tawny) at maturity: perhaps a good species. (Var. alpicola and var. 

 sphserostachya, E(L 1. C. tenella, Ehrh. C. Persoonii, Sieber. C. vitilis, Fries. 

 C. Gebhardi, Hoppe. C. sphaerostachya and C. Buckleyi, Dew.) — On moun- 

 tains, and high northward. (Eu.) 



32. C. Norv6gica, Schk. Pale ; stem 1° or less high, angled ; spikes 

 2-5, rather approximate, oblong, short-bracted, with a few staminate flowers 

 below the numerous fertile ones, or the terminal one all staminate ; perigynia 

 oval or oblong, lenticular, many-nerved, with a short entire beak, equalling the 

 obtuse scale. — Salt marsh, Wells, Maine, Rev. J. Blake. (Eu.) 



+- ■*- Perigynia thin, spongy -thickened at the base, scarcely nerved, 2-toothed. 



33. C. Deweyana, Schw. Spikes about 4; tbe 2 uppermost approximate, 

 the others distinct, the lowest long-bracted ; perigynia oblong-lanceolate, taper- 

 ing into a rough serrate-margined beak, rather longer than the sharply pointed 

 or awned scale. — Copses, New England and New York to Wisconsin, and 

 northward. 



* * Spikes ovoid or obovoid, more or less clustered; perigynia concave-convex, com- 

 pressed, margined or winged, nerved, with a rough 2-toothed beak, often 

 tawny at maturity : scales tawny or white, awnless : bracts bristle-shaped, 

 usually falling before the maturity of the spikes. 



*- Spikes small: perigynia usually (but not always) becoming spongy -thickened at the 



base, the margins rigid. — StellulAt^e. 



++ Spikes completely or incompletely diozcious. 



34. C. exilis, Dew. Spike commonly solitary and cylindrical, dioecious or 

 androgynous (staminate) and contracted below, often with 1 -6 small additional 

 fertile spikes contiguous to the terminal larger one ; perigynia o rate-lanceolate. 

 X>lano-convex, with a few fine nerves only on the convex side, spreading, turning 

 brownish, longer than ovate acute or obtuse scale ; leaves involute-filiform. — 

 Swamps, E. New England to New Jersey, near the coast: also borders of 

 mountain lakes, Essex County, New York. 



35. C. sterilis, Willd. Spikes 4-6, all staminate and rarely all pistillate 

 on some plants, many androgynous, especially the lower spikes, all oblong or the 

 fertile roundish; perigynia ovate from a broad somewhat heart-shaped sharply mar- 

 gined base, flat, diverging or the lower recurved, very acutely 2-toothed at the 

 apex, about equalling the acute or pointed scale ; leaves narrow, involute, pale. 

 (C. stellulata, var. sterilis, of former ed.) — Swamps and wet meadows: com- 

 mon, especially northward. 



