CYPERACE^:. 405 



11. C. chordorhiza Linn. : spikelets 3 5, in an ovoid head; perigynium 

 ovate, acuminate, subrostrate, convex above, equalling the broad-ovate 

 acute scale. 



Sphagnous swamps. N. Y. to Mich. May. 1J-. Culm branching at the 

 base, and rooting at the joints. Leaves of the culm short, of the sterile shoots 

 longer. Rooting Sedge. 



12. C. cephalfiphora Muhl. : spikelets collected into an oval head ; peri- 

 gynium ovate, scabrous on the margin above, about equal to the ovate sub- 

 aristate scale. 



Fields and woods. Can to Car. ; common. May. '2\.. Culm I 2 feet high, 

 wiry, leafy at base. Whole plant green. Oval-headed Sedge. 



13. C. Muhlenbergii Schk. : spikelets 57, crowded at the summit of the 

 culm, bracteate at the base ; perigynium broad-ovate, compressed, nerved, 

 bifid, somewhat diverging, scabrous on the margin, rather shorter than the 

 ovate mucronate scale. 



1 Rocky woods. Mass, and N. Y. to Car. May, June. Q\..Culm 12 feet 

 high, thick. Leaves broad-linear. Plant dark green. Muhlenberg's Sedge. 



14. C. siccata Dew. : spikelets 4 8, staminate above, often wholly stam- 

 inate, ovoid, close, or approximate ; perigynium ovate-lanceolate, acuminate, 

 compressed, scabrous on the margin, bifid, nerved, nearly equal to the ovate- 

 lanceolate scale. 



Sandy plains. Mass, and N. Y. June. '21. Culm 12 18 inches high, slen- 

 der, rough. Plant light green, and of a dried appearance. 



Dry-spiked Sedge. 



15. C. rosea Schk. : spikelets 4 6, remote, about 9-flowered, the lowest 

 one with a setaceous bract exceeding the spike ; perigynium oblong-lance- 

 olate, acuminate, diverging and radiate, rough on the margin, twice as long 

 as the ovate obtuse scale. 



Moist woods. Mass. N. Y. and Penn. to Ohio ; common. May. 1\ . Culm a 

 foot high. Sptitelets mostly about 5, yellowish-green ; lower ones distant. It is 

 sometimes dwarfish, when it forms the var. radiata of Dewey. Rose Sedge. 



16. C. retroflexa Muhl. : spikelets about 4, subapproximate, the lower 

 ones with a short bract ; perigynium ovate, acutish, 2-toothed, smooth on 

 the margin, spreading or reflexed, nearly as long as the ovate acute scale. 



Meadows and pastures. N. S. May. 7|_. Culm about a foot high, slender. 

 Spikelets mostly 4, the two lower ones a little distant, 5 8-flowered. 



Retroflexed Sedge. 



17. C. stipata Muhl. : spike compound, oblong ; spikelets numerous, 

 10 15, oblong, aggregated, bracteate; perigynium lanceolate, subterete 

 and smooth below, spreading, with a long tapering beak which is rough 

 on the margin, twice as long as the ovate-lanceolate scale. 



Wet meadows. Throughout the U. S. April, May. Ij.. Culm 13 feet 

 high, thick and succulent, smooth except at the summit. Spike 2 inches long, 

 straw-color. Beaked Sedge. 



18. C. muricata Linn. : spikelets about 5, ovoid, sessile, approximate, 

 bracteate, lower ones sometimes remotish ; perigynium ovate-lanceolate, 

 plano-convex, 2-toothed, horizontal, scabrous on the margin, sometimes 

 longer than the ovate-lanceolate scale. (Dew.) 



Fields near Boston, Mass. Arct. Amer. Muricate Sedge. 



