314 SYSTEMATIC BOTANY. 



often so ; perigynia erect, lanceolate, acuminate, bifid, longer than the lan- 

 ceolate glume. In swamps and meadows. io'-2o' high. 



2. C. CEPHALOPHORA (Pasture Sedge). Stem rather stout ; spikes 4-6, 

 closely aggregated in an ovoid, bracteate head ; the lower ones sometimes a 

 little remote ; perigynium compressed, broad ovate, green when mature. In 

 dry fields and woods, 6'-i2 f high. 



3. C. SPARGANIOIDES (Pale Sedge). Spikes 7-10, ovoid ; upper ones more 

 or less aggregated ; lower usually distinct, and more or less remote ; peri- 

 gynium broad ovate, not nerved, rough on the margin, compressed, margined, 

 diverging, hispid, green when mature ; style short, swelling at base. 



4. C. VULPINOIDEA (Fox Sedge). Spikes numerous, very dense, gen- 

 erally branching, closely aggregate, forming an oblong, dense, compound 

 spike ; perigynium ovate, broad at base, small, compressed, margined, 

 nerved with a short, bifid, abrupt beak, yellowish when mature. 



5. C. STIPATA ( Three-cornered Sedge). Culm thick, sharply 3-angled, 

 with concave sides ; spikes 6-12, aggregated, lower ones often distinct ; peri- 

 gynium lanceolate, round and truncate at base, destitute of a margin, on a 

 short stalk, nerved, tapering to a long, bifid beak. In wet grounds, lo'-iS' 

 high. 



6. C. ROSE A (Rose' Sedge). Culm low, slender ; spikes several-flowered, 

 3~5) tw uppermost usually approximate, the rast distinct, more or less re- 

 mote ; perigynia oblong, margined, rough on the margin, compressed with a 

 bifid beak, diverging and stellate when mature, twice as long as the broad- 

 ovate, obtuse glume, green at maturity. In low grounds, 8'-i5' high. 



7. C. SCOPARIA (Brown Sedge). Spikes 5-10, somewhat clavate when 

 young, at length ovate, approximate, sometimes aggregated in a dense head ; 

 perigynia narrow lanceolate, nerved, margined, longer than the lanceolate, 

 acuminate glume. In low grounds and meadows, 1-2 feet high. 



8. C. STRAMINEA (Winged Sedge*). Spikes 3-6, roundish-ovoid, alter- 

 nate, approximate ; perigynia roundish-ovate, much compressed, broadly 

 winged, with a short, abrupt, bifid beak, somewhat longer than the lanceo- 

 late glume. A common species in fields along woods, distinguished by its 

 broad, broadly-winged perigynia. 



9. C. POLYTRICHOIDES (Dwarf Sedge}. Culms very low, setaceous ; 

 spike linear, staminate above ; perigynia few, alternate, oblong, somewhat 

 triangular, obtuse, smooth, emarginate, twice as long as the ovate, mostly 

 obtuse glume. In cold swamps and bogs, 2'-4' high. 



10. C. TENTACULATA (Burr Sedge). Fertile spikes 2-3, ovoid-cylindri- 

 cal, densely flowered, approximate, upper one sessile, the others on short 

 peduncles ; bracts leafy, much longer than the culm ; perigynia much in- 

 flated, spreading, smooth, with a long, bifid beak, twice longer than the lan- 

 ceolate, awned glume. 



11. C. STRICTA (Rigid Sedge). Staminate spikes 1-3, cylindric ; fertile 

 2-4, long-cylindric, usually barren above, sessile ; lower one often on a short 

 peduncle ; bracts rarely longer than the culm, auricled at base ; perigynia 

 ovate-acuminate, or elliptical, nerveless, not beaked. Tufts in wet grounds, 

 2-3 feet high. 



