390 CYPERACE^E. (SEDGE FAMILY.) 



spikes 6 to 10, aggregated into an oblong more or less interrupted heavy head, each 

 one subtended by a short setaceous bract : perigynium large, broadly ovate or orbicu- 

 lar-ovate, very conspicuously nerved, about the length of the rough-awned scale. 

 Sterile soil "on the Missouri below Fort Pierre" (Prof. Dewey). 



58. C. cephaloidea, Boott. Distinguished from the last by its broad and 

 long flat leaves (about inch wide), wing-margined entirely nerveless perigynium, 

 and somewhat tawny heads. Fort Pierre, Dakota, and southward. 



* # * Spikes tawny or brown, somewhat chaffy in appearance, closely aggregated 

 or densely capitate: perigynium ovate or ovate-lanceolate, not conspicuously 

 nerved. FCETID.E, Tuckm. 



H- Perigynium conspicuously rough on the angles above. 



59. C. muricata, L. One to two feet high, erect, the culm scabrous : 

 spikes 3 to 12-flowered, approximate into a loosely interrupted head, the lower 

 distinct, the pointed perigynia and scales conspicuous : perigynium green or 

 greenish, stalked, ovate or ovate-lanceolate, nerveless or nearly so, gradually 

 beaked, spreading, about the length of the acute brown scale. Banks, Colo- 

 rado, Utah, and southward. (Eu.) 



Var. confixa, Bailey. Culms very slender, usually prolonged (1 to 2 

 feet high) : spikes 5 to 10-flowered, brown and green or tawny, aggregated 

 into a rather loose continuous oval or oblong naked head (which is \ to 1 inch 

 long): perigynium usually narrower than in the species. C. Hoodii of 

 authors, not Boott. Wahsatch Mountains, Utah ( Watson, 1228); N. W. 

 Wyoming (Parry 281); also in British America, Oregon, and California. 

 Distinguished from No. 58 by its smaller size, weak culm, narrow leaves, nar- 

 row perigynium, and rounder, smaller head. Much like C. Hoodii, Boott, 

 which is distinguished by its stiffer culm, much heavier, more compact, and 

 browner heads, which are made up of more numerous-flowered, more chaffy, 

 and much longer more or less pointed spikes, and more upright perigynia 

 which are mostly concealed beneath the scales. That species occurs in Cali- 

 fornia and Oregon. 



Var. gracilis, Boott. Slender : head more interrupted than in the spe- 

 cies, almost linear, more fuscous, each spike subtended by a pointed or awned 

 bract: perigynium erect, shorter than the very acute or cuspidate scale. 

 C. Hookeriana, Dew. With the species, and northward and eastward. 



H- H- Perigynium smooth or slightly scabrous. 



60. C. fOBtida, All. Creeping: culm 5 to 16 inches high, rather stout, 

 scabrous, longer than the long-pointed leaves : spikes very densely aggregated into 

 a globose or ovoid brown head: perigynium lanceolate or ovate-lanceolate, toothed 

 at the apex, about the length of the acute or mucronate brown scale. Mountains, 

 Colorado, Utah, and Wyoming. (Eu.) 



61. C. incurva, Lightf. ? Extensively creeping : culm stiff and short ( to 

 6 inches long), smooth, usually curved, about the length of the narrow and stiff 

 'curved leaves : spikes 2 to 5, crowded into a short-ovoid or globular brown or 

 tawny head (which is only ^ to f inch long) : perigynium large and turgid, 

 stipitate, broadly ovate, conical above, purple towards the top, faintly many nerved 

 on one side at least, narrowed into a short and stout entire beak, not covered by the 

 acute, thin scale. Rocky Mountains of British America. Immature speci- 



