CYPERACE^. (sedge FAMILY.) 615 



less) ; perigynium very small, ovate and truncate below, bearing a few incon- 

 spicuous short nerves on the outer side, stipitate, firm and at maturity blackish 

 aad shining, the short beak lighter colored ; scale chaffy and acute, about the 

 length of the perigynium. — Swales, N. Eng. to Peun., and westward ; common. 

 (Eu.) — Var. ra.m6sa, Boott. More slender ; head mostly longer, the upper 

 portion often somewhat nodding, the spikes scattered and the lowest ones 

 often slightly compound. N. Y., and westward ; common. 



= = Leaves broader and Jiat {occaslonallj involute in n. 106). 



a. Scales very sharp, mostly rough-tipped. 



1. Perigynium large (2" long or more), nerveless on the inner face. 



105 C. alopeeoidea, Tuckerm. Stout but rather soft, 2-3° high; 

 culm rather sharp, thick and soft in texture; leaves 2-3" wide, about the 

 length of the culm, very green; head 1^' long or less, sometimes green, and 

 occasionally a little compound, the spikes many and compactly or somewhat 

 loosely disposed or tlie lowest often separate and all mostly short-oblong ; 

 perigynium ovate, tapering into a rough beak, very prominently stipitate, 

 with a few brown nerves on the outer face, ascending, about equalling or a 

 little exceeding the scale. — Open swales, N. Y., Penn., and Mich. ; local. In 

 aspect like n. 101. 



Var. sparsispicata, Dewey. Weak, the leaves much narrower and lax ; 

 head 1 - 3' long and linear or nearly so, the spikes smaller and separated or 

 scattered. — S. E. Mich. {Cooley, Clark); little known. 



106. C. gravida, Bailey. Lower and the culm thinner and more sharply 

 angled, 1-2° high ; leaves rather narrower and firmer, shorter than the culm ; 

 head short, always simple, globular or short-oblong, the lowest spikes rarely 

 distinct ; spikes few (4 - 7), globular, or broader than long ; perigynium broadly 

 ovate, nearly twice larger, sessile, plump and somewhat polished at maturity, 

 prominently spreading. — N. 111. to Iowa and Neb. — Var. laxif6lia, Bailey. 

 Much larger, 2-3|° high ; leaves broader (about ^') and lax ; head large and 

 dense, ovoid or oblong, scarcely interrupted. N. 111. to S. Dak. 



2. Perigynium very small, mostly nerved on the inner face. 



107. C. VUlpinoidea, Michx. Mostly rather stiff, 1 - 2|o high; culm 

 very rough, at least above ; leaves various, mostly flat and longer than the 

 culm ; head 1-4' long, usually much interrupted and frequently somewhat 

 compound, varying from dull brown to almost green at maturity, commonly 

 provided with many very setaceous short bracts ; spikes very numerous, as- 

 cending and densely flowered ; perigynium ovate or lance-ovate, mostly ascend 

 Ing. — Low places, variable ; very abundant, especially northward. 



b. Scales blunt, smooth and hyaline-tipped. 



108. C. Sart-Vellii, Dewey. Stiff and strict, U-2i°high; leaves pro- 

 duced into a long slender point, mostly shorter than the culm ; staminate 

 flowers variously disposed, frequently whole spikes being sterile ; head 1 - 3' 

 long and rather narrow, the individual spikes usually clearly defined, or occa- 

 sionally the head interrupted below, tawny-brown ; perigynium elliptic or 

 lance-elliptic, nerved on both sides, very gradually contracted into a short 

 beak; scale about tlie length of the perigynium. (C. disticha, last ed.) — 

 Bogs, central X. Y., west and northward ; frequent. 



