750 OKUER 155. CYPERACEJE. 



suboval or oblong, tapering at base, veined, convex-terete, attenuate above into a 

 terete, sJiortish, straight or subrecurved, bidentate beak, -nearly horizontal in maturity, 

 longer than the ovate and acute glume ; culm slender, 4 to 6' high, with long slen- 

 der leaves sheathing at base. Wayne Co., N. Y. (Sartwell), N. to Greenland. 

 (C. Davalliana, 2d edit.) 



3 C. exilis Dew. (Boott, Illust., No. 45.) $ Spike terminal, ovate or oblong, 

 close flowered, staminate below, sometimes a single $ spike or a single S-spikel 

 perig. ovate-lanceolate, convex above and slightly below, serrulate on the margin, 

 minutely veined above, 2-toothed, diverging, some longer than the ovate-lanceolate 

 glume; culm 12 to 20' high, stiffly erect, and Ivs. setaceous. Swamps, E. Mass. 

 (Oakes), Sandford Lake, N. Y. (Sartwell). 



ft. AXDROGYNA. One or more short ? spikes below the terminal. Manches- 

 ter, N. Y. (Kneiskern). 



4 C. sterilis Willd. (Boott, Illus., No. 135.) Spihe^ compound, $ below, often 

 dioecious ; spikelets 4 6, ovate, subapproximate ; perig. ovate, acuminate or sub- 

 rostrate, bifid, compressed, triquetrous, scabrous on the margin, equaling the ovate, 

 acutish glume ; st. 2f high, erect and stiff. "Wet places, common. (C. stellulata 

 STERILIS Torn, Carey.) 



5 C. bromoides Schk. Spikelets numerous, alternate, $ below, sometimes ail 

 $ ; perig. lanceolate, erect, acuminate, scabrous, nerved, bifid, twice longer than 



the ovate-lanceolate glume. Common in small bogs, in wet places. 



6 C siccata Dew. (Boott, Illust., No. 50.) Spikelets numerous, $ above, often 

 wholly $ , ovate, close or approximate ; perig. ovate, lanceolate, acuminate, com- 

 pressed, nerved, bifid, scabrous on the margin, equaling the ovate, lanceolate glume. 

 Sandy plains, Westfield, Mass. (Davis) ; Ipswich, Mass. (Oakes) ; widely spread 

 over the country, but not abundant, W. to 111. 



7 C. Sartwellii Dew. Spikelets 12 20, ovate, sessile, compact, bracteate, lower 

 ones especially fructiferous ; upper often $ at apex, sometimes wholly $ ; perig. 

 ovate, lanceolate, convexo-concave, subulate, slightly 2-toothed, margined and 

 scabrous on the edge, a little longer than the ovate and acute glume ; Ivs. flat, 

 linear, shorter than the stem. Junius, Seneca Co., N. Y. (Sartwell). 



8. C. distycha Huds. Spikelets many, 2-rowed or compressed into a flattened, 

 compound, loose spike ; spikelets oblong-ovate, close, alternate, often branched be- 

 low and the lowest sometimes remote, upper and lower often $ , and the inter- 

 mediate wholly $ , or from the middle wholly $ upwards ; perig. ovate, narrow- 

 rostrate, margin serrulate, narrow, equaling the ovate, acute glume ; culm erect, 

 leafy below. Wis. (Lapham), 111. (Vasey), Mich. (Cooley), N. to Arc. Am. (C. 

 intermedia Good.) 



9. C. decoqjposita Muhl. (Boott, Illust., 53.) Spike decompound or paniculate; 

 spikelets very many, ovate, alternate ; perig. ovate, convex on both sides, triangu- 

 lar, acutish or short rostrate, short, brownish, glabrous, larger than the ovate, acu- 

 minate, whitish glume; st. 18 30' high. Found in swamps, Michigan, and in 

 Yates Co., N. York (Sartwell). 



10 C. prairea Dew. Spike below branched ; spikelets ovate, sessile, 5 to 7 on a 

 branch ; perig. ovate-lanceolate, convex both sides, scabrous on the margin, slightly 

 bifid, smaller than the ovate-lanceolafe glume ; st. 2 3f high, leafy towards the 

 base. Abundant, in the prairies, of Michigan, and sparingly found in N. England 

 and N. Y. Resembles C. paniculata L., which has a much broader ovate glume 

 shorter than the perigynium and is far more paniculate, and for which this has 

 been taken. From No. 24 it is far separated by its panicle, and the color and 

 shape of its fruit. 



11 C. cephalophora Willd. Spikelets ovate, densely aggregated into an ovate 

 head (!' long), bracteate, about 5 ; perig. ovate, acuminate, compressed, bifid, 

 .scabrous on the margin, with a short, ovate, and scabro-cuspidate glume, which 

 equals it; st. 8 16' high. Borders of fields and woods, common, but not 



. abundant. 



12 C. Muhlenbergii Schk. Spikelets alternate, obtuse, approximate into an 

 ovate-oblong head, ' long, with a long bract at the lower one ; perig. ovate, con- 

 vex above, very smooth, nerved, bifid, scabrous on the margin, some diverging, 

 a little shorter than the ovate and mucronate glume; st. 1218' high. la 



