552 CYPERACE^E. (SEDGE FAMILY.) 



1. CYPERUS, L. GALINGALE. (PI. 1.) 



Spikes many - few-flowered, mostly flat, variously arranged, mostly in clusters 

 or heads, which are commonly disposed in a simple or compound terminal 

 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. Achenium lenticular or triangular, naked at the 

 apex. Culms mostly triangular, simple, leafy at the base, and with one or 

 more leaves at the summit, forming an involucre to the umbel. Peduncles 

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

 (KuTretpos, the ancient name.) 



1. PYCREUS, Beauv. Style 2-clefl: achenium flattened : spikes flat, many-flow- 

 ered: only the lowest scald empty. (Ours all annuals.) 



1. C. flav6scens, L. Stamens 3; spikes becoming linear, obtuse, clus- 

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

 achenium shining, orbicular. Low grounds, mostly near the coast. Culms 

 4'- 10' high; spikes 5" -8" long. Involucre 3-leaved, very unequal. (Eu.) 



2. C. diandrUS, Torr. Stamens 2, or sometimes 3; spikes lance-oblong, 

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

 purple-brown on the margins or nearly all over; achenium dull, oblony-obovate : 

 otherwise much like the last. Var. CASTANEUS, Torr. (C. castaneus, Bigel.) 

 is only a form with browner scales. Low grounds : common. 



3. C. Nuttallii, Torr. Stamens 2; spikes lance-linear, acute and very 

 flat (' - 1' long), crowded on the few very short (or some of them distinct) rays ; 

 scales oblong, yellowish-brown, rather loose ; achenium oblong-obovate, very blunt, dulL 

 Salt or brackish marshes, Massachusetts to Virginia, and southward. Culms 

 4' -12' high. C. minimus? Nutt. (C. Cleaveri, Torr.) is a depauperate form 

 of this, with a 1 -leaved involucre, and only one or two spikes ! 



4. C. flavicomus, Michx. Stamens 3; spikes 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; achenium obovate, mucronate, blackish; culm stout (l-3 

 high) ; leaves of the involucre 3-5, very long. Low grounds, Virginia and 

 southward. 



2. PAPYRUS, Thouars. Style 3-clfft: achenium triangular: stamens 3: 

 spikes many-flowered : the scarious winged margins of the joints of the axis 

 early separating down to the base in the form of a pair of free scales, which 

 are persistent after the proper scale falls away : otherwise as in 3. ( Ours 

 annual.) 



5. C. erythrorhizos, Muhl. Culm obtusely triangular (3' -3 high); 

 umbel compound, many-rayed ; involucre 4 - 5-leaved, very long ; involucels 

 bristle-form ; spikes very numerous, crowded in oblong or cylindrical nearly 

 sessile heads or spikes, spreading horizontally, linear, flattish (3" -6" long), 

 bright chestnut-colored ; scales lanceolate, mucronulate. Alluvial banks, Penn. 

 to Wisconsin ? Illinois, and common southward. Root fibrous, red. 



