T, Holm — Studies in the Cyperacece. 461 



Chionanthce nob. 

 Spikes several, snow-white, androgynous, the staminate por- 

 tion dense-flowered, the pistillate few-flowered, almost sessile 

 in a ronndish or oval head ; bracts foliaceoiis with long and 

 green blades ; scales white, ovate, acute or obtuse ; perigynia 

 white with a few minute, pnrplish streaks and spots above, 

 oblong, trigonous, sessile, two-nerved, glabrons, somewhat 

 inflated, the beak very short, entire, but erosely denticulate 

 around the orifice ; stigmata three ; rhacheola not developed. 

 Centralis : C. Balden sis L. 



Leucocephalm nob. 

 Spike single, snow-white, androgynous, dense-flowered; 

 scales of staminate flowers elliptical, those of the pistillate 

 broad and obtuse to emarginate, all white ; perigynia some- 

 what spreading, membranaceous, whitish, elliptical, sessile, 

 faintly nerved, glabrous, the beak very short, obliquely cut; 

 stigmata three ; rhacheola well-developed ; leaves destitute of 

 sheath, ligule and midrib. 

 Centralis : C. Fraseri Andrews. 



Elynanthm nob. 

 Spike single, androgynous, the pistillate portion few-flowered ; 

 scales brown, very broad, amplectent ; perigynia membrana- 

 ceous, whitish to brown, erect, oval to obovoid, obtusely tri- 

 angular in cross-section, sessile, faintly two-nerved, pubescent 

 above, the beak short, but distinct, with hyaline entire or 

 obliquely cut orifice ; stigmata three. 

 Hehetatce: C. filifoUa. Nutt., elynoides Holm. 



Sphmridiophorce Drej. 

 Spikes several, the terminal staminate, clavate, the lateral 

 pistillate and roundish, few-flowered, sessile or the lowest one 

 peduncled, erect, contiguous to remote ; bracts foliaceous, nar- 

 row, sheathless ; scales brownish or purplish, acuminate, often 

 mucronate ; perigynia dark green, slightly spreading, elliptical 

 to obovate or globose, trigonous, sessile or shortly stipitate, 

 obscurely nerved, more or less pubescent, the beak short, emar- 

 ginate to bidentate with the teeth erect ; stigmata three. 

 Hehetatce: C. scirpoidea Michx. 



Centrales: C. ericetorum Poll., memhranacea Poll., polyrrhiza 

 Wallr., proecox Jacq., montana L., Moorcroftii Boott, varia 

 Muehl., conimimis Bail., piluUfera L., hreviculmis R. Br., 

 deflexa Hornem., Hossil Boott, pennsylvanica Lam., vere- 

 cunda nob.,* turbinata Liebm., Floridana Schw., leucodonta 

 nob.f 

 * = inops Bail, non Kunze. f = rigens Bailey non Boott. 



