204 CYPERACEAE (SEDGE FAMILY) 



^ dm. high, scabrous above ; leaves 1-2 mm. wide, flat, about half 



8J. as long as the culms; heads slender, 1-2.5 cm. long, of 27 remote 



% /\ appressed-ascending spikes; spikes either staminate (clavate), 



tfc w androgynous, or pistillate (ovoid) ; bracts ovate, concave ; glumes 



\A ovate, subspathiform, emarginate at tip, more or less marked with 



I (U green and brown ; style with 2 elongate branches, the slender 



| v base becoming chartaceous and subpersistent, finally separating 



589 K elachy- ^ rom tne truncate subterete nerveless pale achene (1.2-1.5 mm. 



^ long) ; stamens 2, the anthers much exceeding the filaments. 



Wet banks of Aroostook R., Me.; local. June, July. FIG. 339. 



18. CAREX [Ruppius] L. SEDGE 



Flowers unisexual, destitute of floral envelopes, disposed in spikes ; the 

 staminate consisting of three stamens, in the axil of a bract, or scale ; the pistil- 

 late comprising a single pistil with a bifid or trifid style, forming in fruit a hard 

 achene, which is inclosed in a sac (periyynium) borne in the axil of a bract, or 

 scale. Staminaje and pistillate flowers borne in different parts of the spike 

 (spike androgynous), or in separate spikes on the same culm, or rarely the 

 plant dioecious. Perennial grass-like herbs with mostly triangular culms, 

 3-ranked leaves, and spikes in the axils of leafy or scale-like bracts, often aggre- 

 gated into heads. An exceedingly critical genus, the study of which should be 

 attempted only with complete and fully mature specimens. 1 (The classical 

 Latin name, of obscure signification ; derived by some from Kftpeiv, to cut, on 

 account of the sharp leaves as indicated in the English name Shear-grass.) 



1. Spikes mostly uniform and sessile, bearing the staminate flowers at base or 

 apex or sometimes scattered amongst the pistillate ; stigmas 2 and achenes 

 lenticular. VlGNEAE [Beauv.] Koch. (For 2, see p. 209.) 



A. Staminate flowers scattered or at the base of the spikes (only in 

 exceptional individuals and in the often dioecious C. gynocratti 

 and C. efili* the entire spike staminate) B. 

 B. PKRIGYNIA WITH THIN OR WINGED MARGINS C. 



C. Perigynia ascending, the tips only sometimes wide-spreading or 

 recurved, not spongy at base, the margins winged at least 

 toward the beak />. 

 D. Bracts wanting or setaceous, if broad at most twice as long as 



the inflorescence E. 

 E. Strongly stoloniferous ; culms rising from an elongated 



rootstock ; perigynia firm, 5-6 mm. long . . 4. C. siocata. 



E. Not strongly stoloniferous ; culms solitary or in stools F. 

 f. Perigynia less than 2 mm. broad G. 

 G. Perigynia 5 mm. or more long H. 

 H. Perigynia 7-10 mm. long ; spikes long-cylindrlc, 



pointed, 1.5-2.5 cm. long 1. C. muskingumenate. 



H. Perigynia snorter (or, when exceptionally 7 mm. long, 



in shorter spikes) /. 

 /. Perigynia half as broad as long, plump, nerveless 



or obscurely short-nerved on inner face . . 22. C. cwn&a, 

 1. Perigynia one third as broad as long J. 

 J. Perigynia thin, scale-like, scarcely distended over 

 the achenes, distinctly nerved on the inner 

 face and prominently exceeding the subtend- 

 ing scales. 

 Leaves at most 3 mm. wide ; spikes 39, glossy 



brown or straw-colored, pointed. 

 Inflorescence oblong-ovoid or subcylindric, 



with ascending approximate spikes . 2. C. ncoparia. 



Inflorescence moniHform . . (2) C. scoparia, v. moniliformit. 

 Inflorescence subglobose or broad-ovoid, 



spikes crowded and divergent . . (2) C. scoparia, v. condnsa. 

 Leaves more than 3 mm. wide; spikes 8-14, 



green or dull brown, blunt . . . 8. C. tributoides. 



1 The peripynial characters are here based on study of mature plants. In gen- 

 eral the perigynia at the tip of the spike are less characteristic than those nearer 

 the middle ; and, if possible, the latter alone should be ased in critical comparisons. 



