376 CYPERACE.E. (SEDGE FAMILY.) 



* Culms all as long or nearly as long as the leaves : staminate flowers conspicuous . 

 pistillate flowers very few and large: beak very short. — Phtllostacht^;, 

 Bailey. 



10. C. Geyeri, Boott. Stoloniferous : culms very slender, angled, rough, 

 about a foot high, about the length of the flat rough-edged leaves : staminate 

 portion of the spike usually appearing distinct, J to 1 inch long : pistillate 

 flowers 1 or 2, large, erect with the rhachis : perigynium triangular-obovoid, 

 3 lines long, the conspicuous angles obtuse, one-nerved on the two inner sides, 

 very smooth, with a very short entire erase and hyaline beak : scales thin and 

 brown, acute, 2 to 4 times the length of the perigynium. — Mountains of 

 Colorado, Utah, and Montana. Hitherto confounded with C. multicaitlis, 

 Bailey, a Californian and Oregon species with numerous prolonged stiff terete 

 and smooth culms. 



* * Culms mostly much shorter than the leaves: staminate flowers inconspicuous : 



perigynium small, the beak produced to half its length {or more) : scales very 

 green and much dilated, often concealing the perigynia, and readily mistaken 

 for bracts. — Bractoide;e, Bailey. 



11. C. Backii, Boott. Cespitose: culms 1 to 7 inches high, sharply an- 

 gled : leaves lax and smooth : staminate portion of the spike about 3-flowered : 

 pistillate flowers 2 to 4, aggregated, more or less spreading : perigynium glo- 

 bose-ovate, inconspicuously nerved, smooth or very slightly scabrous above : 

 lower scales longer than the culm. — Dry and rocky hills, Colorado (Hall and 

 Harbour), and British America. 



§ 4. Staminate and pistillate spikes distinct : staminate spike single, more or less 

 peduncled : pistillate spikes more or less elongated and peduncled, loosely alter- 

 nate-flowered (except in C. Richardsoni and No. 13) : bracts always sheathed 

 (except in No. 13), the sheaths sometimes membranaceous and leafless: peri- 

 gynium 3-angled or globular, tightly enclosing the achenium, faintly nerved or 

 nerveless, more or less hairy in the less evolved species, smooth and the short 

 beak curved in the Laxiflora. — Dactylostachy.s:, Drejer (in part). 

 Mostly low or undersized species, with a loose habit, growing in dry or 

 grassy places. 



* Sheaths membranaceous or hyaline, either not prolonged into a bract or the bract 



very short and not foliaceous : perigynium more or less 3-angled, hairy in our 



species and the beak straight. — Digitate, Pries. 

 C. Richardsoni, R. Br., connecting this section with § 2, is distinguished 

 from C. Pennsylvania, which it strongly resembles, by its peduncled spikes 

 and dark purple leafless sheaths. It occurs in the Eastern States, British 

 America, and California, and may be expected in Montana. 



12. C. concinna, R. Br. Stoloniferous: culms slender, 2 to 6 inches 

 high, longer than the sharp-pointed leaves : staminate spike small, shortly 

 stalked, its scales obtuse, rarely bearing 1 or 2 pistillate flowers at the top : 

 pistillate spikes 2 to 5, short, rather loosely 2 to 9-flowered, at least the lower 

 ones distinctly peduncled (the peduncles often included in the sheaths), all ap- 

 proximate or aggregated: sheaths very short, each usually bearing an awn-like 

 bract of its own length : perigynium ovate, strigose-hairy, with a short erose beak, 

 longer than the obtuse hyaline-margined scale. — Cottonwood Lake, Wasatch 



