CYPERACE^E. (SEDGE FAMILY.) 569 



Tribe IV. C ARICE^E. Flowers monoecious in the same (androgynous) or in separate 



spikes, or sometimes dioecious. Achene enclosed in a sac ( perigynium). 

 16. Carex. Hypogynous bristle short and enclosed in the perigynium or none. 



1. CYPBRUS, Tourn. GALINGALE. (PI. 1.) 



Spikelets many - few-flowered, mostly flat, variously arranged, mostly in 

 clusters or heads, which are commonly disposed in a simple or compound ter- 

 minal umbel. Scales 2-ranked, conduplicate and keeled (their decurrent base 

 below often forming margins or wings to the hollow of the joint of the axis next 

 below), deciduous when old. Stamens 1-3. No bristles or inner scales. Style 

 2 - 3-cleft, deciduous. Achene lenticular or triangular, naked at the apex. 

 Culms mostly triangular, simple, leafy at base, and with one or more leaves at 

 the summit, forming an involucre to the umbel or head. Peduncles or 

 rays unequal, sheathed at base. All flowering in late summer or autumn. 

 ( Kviretpos, the ancient name.) 



1. PYCKfcUS. Achene lenticular, the edge turned to the rhachis ; spikelet 



flattened, many-flowered ; rhachis narrow, not winged. Annuals. 



* Umbel simple or capitate, rarely slightly compound. 



1. C. flavescens, L. Culms 4-10' high; spikelets 5-8" long; invo- 

 lucre 3-leaved, very unequal ; spikelets becoming linear, obtuse, clustered on 

 the 2-4 very short rays (peduncles); scales obtuse, straw-yellow ; stamens 3; 

 achene shining, orbicular, its superficial cells oblong. Low grounds, N. Eng. 

 to Mich., 111., and southward. (Eu., etc.) 



2. C. diandrus, Torr. (PI. 1, fig. 1-4.) Spikelets lance-oblong (3 - 9"), 

 scattered or clustered on the 2-5 very short or unequal rays ; scales rather ob- 

 tuse, purple-brown on the margins or nearly all over; stamens 2, or sometimes 

 3 ; achene dull, oblong-obovate ; otherwise much like the. last. Low grounds, 

 common from the Atlantic to Minn., Ark., and N. Mex. Var. CASTANEUS, 

 Torr. Scales more firm and browner ; with the type. 



3. C. Nuttallii, Torr. Culms 4-12 / high; spikelets lance-linear, acute 

 and very flat (- V long), crowded on the few usually very short (or some of 

 them distinct) rays; scales oblong, yellowish-brown, rather loose; stamens 2; 

 achene oblong-obovate, very blunt, dull. Mostly in salt or brackish marshes, 

 along the coast, from Mass, to the Gulf. 



4. C. polystachyus, Rottb., var. leptostachyus, Boeckl. Culms 

 very slender, 6-15' high ; leaves and elongated involucre very narrow; spike- 

 lets few to many on the 4-8 rays, linear, acute, 2 - 9" long ; scales thin, ovate, 

 2cute, closely imbricated, pale brown ; stamens 2 ; achene linear-oblong or clavate, 

 short-pointed, grayish and minutely pitted. (C. microdontus, Torr.) Margins 

 of ponds and streams, Va. to Fla. and Tex. 



* * Umbel compound. 



5. C. flavicomus, Vahl. Culm stout (1 -3 high) ; leaves of the invo- 

 lucre 3-5, very long; spikelets linear (4-9"' long), spiked and crowded 

 on the whole length of the branches of the several-rayed umbel, spreading ; 

 scales oval, very obtuse, yellowish and brownish, broadly scarious- (whitish-) 

 margined; stamens 3; achene obovate, mucronate, blackish. Low grounds, 

 Va. to Fla. 



