178 



CYPERACEAE (SEDGE FAMILY) 



224. C. lancastriensis. 



225. C. hystriciims. 



short-cylindric or obovoid close heads, soon reflexed, 0.8- 

 1.5 cm. long, of 3-6 narrow scales, the upper and lower 

 empty, nearly twice the length of the linear-oblong 

 achene. Rich soil, N. J. and Pa. to Ga. FIG. 224. 



25. C. hystricinus 

 Fernald. Slender ; the 

 smooth rigid culm 2-5 

 dm. high, much exceed- 

 ing the stiff narrow (2-5 

 mm. broad) smooth 

 leaves; umbel of 3-10 

 simple smooth rays, 

 mostly shorter than the 

 involucre ; spikelets 1-2- 

 flowered, subulate, rigid, 

 3-7 mm. long, densely 

 crowded in cylindric or narrowly obovoid heads (1-2.5 cm. long), strongly 

 reflexed, golden-brown at maturity; scales closely appressed, the fertile strongly 

 nerved, the terminal involute-subulate; achene linear, 2-2.5 mm. long. L)ry 

 sand, N. J. to Ga. FIG. 225. 



26. C. dipsacif6rmis Fernald. Culm scabrous, at least above, 2.5-8 dm. 

 high ; leaves shorter than the culm, scabrous-hispid above, 4-9 mm. wide ; umbel 

 4-12-rayed, some of the smooth rays equaling the involucre ; 

 spikelets 1-3-flowered, subulate, rigid, 6-11 mm. long, crowded 

 in cylindric, or subcylindric heads (1.5-4 cm. long), strongly 

 deflexed, yellow-brown at maturity ; fertile 

 scales with green midribs ; achene 3 mm. 

 long. Sandy barrens and dry woods, N. J. 

 to Ky. and Ga. FIG. 226. 



27. C. retrofractus (L.) Torr. Culm 

 (0.3-1 in. high) minutely downy and rough 

 on the obtusish angles / leaves hairy, short 

 and stiff, 0.4-1 cm. wide, the margins becom- 

 ing revolute ; umbel with 4-12 upright usu- 

 ally scabrous rays mostly longer than the 



involucre; spikelets slender-awl-shaped, very numerous in 

 turbinate-obovoid greenish or drab heads (1-2.5 cm. long), 

 soon strongly reflexed, 1-2-flowered in the 

 middle (5-8 mm. long) ; scales usually 4 

 or 5, the two lowest ovate and empty, the 

 fertile lanceolate and pointed, the upper- 

 most involute-awl-shaped ; achene linear, 

 2.5-3 mm. long. Sandy or rocky soil, 

 N. J. to Fla. and Tex. ; northw. in the low 

 country to Mo. FIG. 227. 



28. C. ovularis (Michx.) Torr. Culm 229. C. cyhndncus. 



smooth, sharply triangular (2.5-7 dm. high) ; um- 

 bel 1-6-rayed ; spikelets (50-100) in a globular 

 head, 3-flowered, oblong, blunt (3-5 mm. long) ; 

 scales ovate, obtuse, a little longer than the linear- 

 oblong achene. Sandy dry soil, s. N. Y. to 111., 

 Kan., and south w. ; rarely on ballast, Mass. FIG. 

 228. Var. ROBUSTUS Boeckl. is a form with large 

 heads, the spikelets 3-4-flowered (7-10 mm. long). 

 111. to Ark., and southw. 



29. C. cylindricus (Ell.) Britton. Similar to 

 the last, but the heads short-cylindrical; spikeleU 

 usually 2-flowered. (C. To rr'eyi Britton.) L. I. 

 to Fla., w. to Tex. FIG. 229. 

 280. C.echinatus. 30. C. echinMus (Ell.) Wood. Culm smooth 



226. C. dipsaciforinis. 



227. C. retrofractus. 



228. C. ovularis. 



