CYPERACE^E. (SEDGE FAMILY.) 575 



base; scale acute, rather shorter than the perigyniura ; achenium obovoid-pyriform, 

 obtusely triangular. ( C. paniculata, var. teretiuscula, Wahl. ) Swamps, especially 

 northward. (Eu.) 



Var. major, Koch. Spikes more panicled; perigynia rather narrower. 

 (C. Ehrhartiana, Hoppe. C. prairiea, Dew.) Bogs and low grounds, New 

 England to Wisconsin, and northward. (Eu.) 



14. C. decomp6sita, Muhl. Panicle large, with very numerous densely- 

 crowded spikes on the rather short spreading branches ; periyynia obovate, un- 

 equally biconvex, sessile, with a short very abrupt beak, conspicuously nerved on each 

 side, about the length of the ovate pointed scale. (C. paniculata, var. decom- 

 posita, Dew.) Swamps, W. New York (Sartwell) to Pennsylvania, Illinois, 

 and southwestward. 



# * Perigynia small, compressed, 2-3-nerved, membranaceous, with a short 



2-toothed rough beak, yellow or brown at maturity : spikes decompound, with 

 numerous small very densely-Jlowered heads : scales of the fertile spikes tawny, 

 with the green keel prolonged into a rough point: bracts short and resem- 

 bling them at the base, or often becoming green and bristle-shaped, and 

 much exceeding the culm. MULTIFIX^ILS;. 



15. C. vulpinoidea, Michx. Spike oblong and dense, or more or less 

 interrupted f (l'-2' long), of 8-10 crowded clusters; perigynia ovate from a 

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

 flora, Muhl. C. bractebsa and C. polymdrpha, Schw. C. microsperma, Wahl.) 

 Varies with the perigynium narrower, and the beak tapering and more 

 strongly serrulate. (C. setacea, Dew,) Low meadows : everywhere common. 



# # # Perigynia on short stalks, plano-convex, without a margin, membranaceous, 



with a thick and spongy base and a long tapering 2-toothed rough beak, dis- 

 tinctly nerved (only obscurely so in No. 19 and 20), widely spreading and 

 yellow at maturity : spikes dense, more or less aggregated, sometimes decom- 

 pound: scales of the fertile spikes tawny, with a sharp point: bracts bristle- 

 shaped, shorter than the thick and triangular culms. VULPINE. 



16. C. crus-corvi, Shuttleworth. Spike very large, decompound, the 

 lower branches long and distinct, the upper shorter and aggregated ; brads o/len 

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

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

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

 southwestward. A conspicuous, very large species, with spikes 4' -9' long, 

 often somewhat paniculate, and glaucous leaves 6" wide. 



17. C. stipata, Muhl. Spikes 10-15, aggregated, or the lower mostly 

 distinct and sometimes compound ; perigynia lanceolate, with a long beak tapering 

 from a truncate base, many-nerved, much exceeding the scale ; style slightly tumid at 

 the base. (C. vulpinoidea, Torr., Cyp., not of Michx.) Low grounds: com- 

 mon. Culm flaccid : spikes pale. 



18. C. COnjtincta, Boott. Resembles the preceding; but the spikes 

 (6-12) more simple; perigynia ovate from a subcordate flat (not corky-tumid) 

 base, short-beaked, fewer-nerved, longer and broader than the pointed scale ; 

 style bulbous at the base. (C. vulpma. of former editions; from which it 



