CYPERACE^E. (SEDGE FAMILY.) 513 



* # * * Periyynia sessile, plano-convex, compressed, more or less margined, mem- 

 branaceouti, with a rather short and rough (or wholly smooth in No. 26) 

 2-toothed beak, spreading and greert at maturity: scales of the fertile spikes 

 tawny or white: bracts bristle-shaped, commonly shorter than the culm. 



MUHLENBERGIAN^E. 



22. C. SparglliliOldes, Muhl. Spikes 6-10, ovoid; the upper ones ag- 

 gregated, the lou~r distinct and more or less distant ; periqynia broadly-ovate, nerveless, 

 rough on the narrow margin, about twice the length of the ovate-pointed scale ; 

 achenium roundish-ovate; style short, tumid at the base. Var. CEPHALOfDEA is a 

 reduced state, with 4-6 rather smaller spikes, closely aggregated into an oblong 

 head; resembling No. 23 in general appearance. (C. cephalophora, var. cepha- 

 loidea, & C. cephaloidea, Dew.) Low rich grounds; not rare: the var. in 

 fields and hedges. A robust species, with rather wide pale-green leaves; some- 

 times with 1-2 short branches of a few spikes each at the base of the compound 

 spike (probably C. divulsa, Pursh, not of Goodenough). 



23. C. CCpliaI6pllOra, Muhl. Spikes 5-6, small, and densely aggregat- 

 ed in a short ovoid head; perigynia broadly ovate, with 3 4 indistinct nerves on the 

 outer side, scarcely longer than the ovate roughly-pointed scale ; acheniuin and 

 style us in the last. (C. Leavenworthii, Dew.) Woods and fields ; common. 



24. C. niiiEl&eiibei'gii, Schk. Spikes 5-7, closely approximate, forming 

 an oblong head ; periqynia orbicular-ovate, with a very short beak, prominently nerved 

 on both sides, about the length of the ovate roughly-pointed scale ; aditniwn or- 

 bicular, with a very short bulbous style. Fields ; rather common, especially south- 

 ward. Plant 12'- 18' high, pale green, commonly with a bract at the base of 

 each spike. 



25. C. I'OSea, Schk. Spikes 4-6, the 2 uppermost approximate, the others 

 all distinct, and the lowest often remote; perigynia oblong (about 8-10 in each 

 spike), narrow at the base, widely diverging at maturity, twice as long as the 

 broad/ 1/ ovate obtuse scale. Varies with weak slender culms, and small 3 - 4-flow- 

 ered spikes. (Var. RADIATA, Dew. C. neglecta, Tuckerman.) Moist woods 

 and meadows ; common. 



26. C. retl'Oflexa, Muhl. Spikes 4-5, all approximate, the 1-2 lowest 

 distinct but not remote ; perigynia (about 5 - 7 in each spike) ovate, or ovate-lan- 

 ceolate, smooth on the margin and beak, not much exceeding the ovate-lanceolate pointed 

 scale, widely spreading or reflexed at maturity. (C. rosea, var. retroflexa, Torr , 

 Cyp.) Copses and moist meadows ; less common than the last, from which it 

 is distinguished by the smaller approximate spikes, longer and sharper scales, 

 and especially, from every species in this subsection, by the smooth margin and 

 beak of the perigynium. 



***** Perigynia plano-convex, without a beak, of a thick and leathery texture, 

 prominently nerved, smooth (except on the angles), with a minute and entir* 

 or slightly notched tchite mcmbranaceous point : achenium conformed to the peri- 

 gynium, crowned with the short thick style : bracts like the scales (brown), 

 the lowest with a prolonged point : rootstock creeping. CHORDORHIZ.K. 



27. C. ctlOl'doi'lliza, Ehrh. Culms branching from the long creeping root' 

 stock (4' -9' high), smooth and naked above, clothed at the base with short ap- 



