512 CYI'ERACE^. (sedge FAMILY.) 



16. C. VUlplnoii<lea, Michx. Spike oblong and dense, or more or less 

 inten-upted, of 8-10 crowded clusters (Ii^'-2|' long) ; perigynia ovate from a 

 broad base, with a more or less abrupt beak, diverging at maturity. (.0. multi- 

 flora, MuU. C. bvacteosa and C. polymorpha, Schw. C. microsperma, WaJd.) 



— Varies with the perigynium narrower, and the'beak tapering and more strongly 

 serrulate. (0. setacea. Dew.) — Low meadows; very common. — Vaiies ex- 

 ceedingly in the size and shape of the perigynium and beak. 



* * * Perigynia on short stalks, plano-convex, withmt a marc/in, membranaceous, 

 ivith a thick and spongy base and a long tapering 2-toothed rough beak, disiinct- 

 • ly nerved (only obscurely so in No. 20 and 21), widely spreading and yellow at 

 maturity : spikes dense, more or less aggregated, sometimes decompound : 

 scales of the fertile spikes tawny, with a sharp point ; bracts bristle-shaped, 

 shorter than the thick and triangular culms. — VuLpiNiE. 



17. C. crus-Cdrvi, Shuttleworth. Spike very large, decompound, the 

 lower branches long and distinct, the upper shorter and aggregated ; bracts often 

 2-toothed at the base ; perigynia attenuated from an ovate dilated and truncate base into 

 a very long slightly-ivinged beak, much exceeding the scale; style tumid at the base. 

 (C. sicffiformis, Boott. C. Halei, Dew.) — Swamps, Ohio to Wisconsin, and 

 southward. — A conspicuous, very large species, with spikes 4'-9' long, often 

 somewhat paniculate, and glaucous leaves J' wide. 



18. .C Stipsita, Muhl. Spikes 10-15, aggregated, or the lower ones dis- 

 tinct and sometimes compound ; perigynia lanceolate, with u, long beak tapering 

 from a truncate hose, much exceeding the scale; style not tumid at the base. {C. vul- 

 pinoidea, Torr., Cyp., not of Michx.) — Swamps and low grounds ; common. 



19. C. vnlplna, L. Spikes numerous, aggregated into a cylindrical and 

 dense (or at times elongated and somewhat interrapted) compound spike; peri- 

 gynia compressed, tapering frcmt a broadly-ovate base into a beak not much longer than 

 the scale ; achenium oval ; style tumid at the base. — Ohio, Illinois, and Kentucky. 



— A tall, robust species, 3" -4° high, with wide leaves and a remarkably thick 

 rough cnlm. It is very like the last, fropi which it chiefly differs in the more 

 compressed and wider base and shorter beaks of the perigynia. — The forms 

 with intejTupted spikes have also a general resemblance to No. 22; which, how- 

 ever, is distinguished by the margined and nerveless perigynia. (Eu.) 



20. C. alopecoides), Tuckerman. Head of 8-10 aggregated spikes, 

 oblong, dense ; perigynia compressed, very obscurely nerved, ovate from a broad tnm- 

 cate or somewhat heart-shaped base, a little longer than the scale ; achenium pyri- 

 form; base of the style not tumid. (C. cophalophora, var. maxima. Dew.) — 

 Woods, W. New York to Penn., ^tfichigan, &c. — Much resembling the last, 

 but smaller, with shorter and more compact spikes ; easily distinguished by the 

 nearly nerveless perigynia, and the different achenium and style. 



21. C. iniiricata, L. Spikes 4 - 6, ovoid, approximate but distinct, the 

 lowermost sometimes a little remote ; perigynia ovate-lanceolate, somewhat com- 

 pressed, nerveless, or very obscurely nerved towards the base, rather longer than the 

 scale ; achenium ovate, base of the style not tumid. — Fields, Massachusetts (in- 

 troduced ?), Ohio, and Kentucky ; rare. — Spikes mostly looser than in the last, 

 the perigynia narrower, with a longer and more tapering beak. (Eu.) 



