CYPERACEAE (SEDGE FAMILY) 



191 



285. S. femithii. 



286. S. americanus. 



1-5 ovoid acutish spikelets (0.5-1 cui. long); involucral leaf always 

 erect; scales oblong-oval; style 2-cleft ; bristles 1 or 2 minute 

 rudiments or none ; acliene cuneate-obovate. — Wet shores, local, 

 Me. to Pa., Ill, Mich., and Ont. July-8ept. Fig. 285. Var. 

 SETosus Fernald. Perianth of 4 or 5 slender retrorsely barbed 

 bristles, mostly exceeding the acheues. — Me. ; 

 Mass. ; and 111. 



12. S. americanus Pers. Eunning rootstocks 

 long and stout ; cuhns sharply 'd-angled through- 

 out (0.2-1 m. high) with concave Sides; leaves 

 1—'], elongated (1-3 dm. long), keeled and chan- 

 neled ; involucral leaf pointed ; spikelets 1-6. capitate, ovoid, 

 mostly 0.5-1 cm. long ; scales ovate, sparingly ciliate, 2-cleft 

 at the apex ; anthers tipped with an awl-shaped minutely fringed 

 ajypendage ; style 2-cleft (rarely 3-cleft); bristles 2-6, shorter 

 than the smooth achene. {S. pungens Vahl.) — Borders of 

 salt and fresh ponds and streams, temperate N. A. Aug.- 

 Oct. (Eu., S. A.) Fig. 286. 

 13. S. Torreyi Olney. Bootstocks slender and iceak ; culm 3-angled^ with 

 concave sides, rather slender (0.4-1.5 m. high), leafy at base ; leaves 2 or 3, ?nore 

 than half the length of the culm, triangular-channeled, slender ; 

 involucral leaf blunt ; spikelets 1-4, oblong or spindle-shaped, 

 acute, distinct, 1-1.5 cm. long ; scales ovate, smooth, barely mu- 

 cronate ; style o-cleft ; bristles longer than the unequally triangular 

 very smooth long-pointed achene. — Borders of ponds, brackish 

 and fresh. Me. to Pa., la., and Man. Aug., Sept. 

 Fig. 287. 



14. S. Olneyi Gray. Culm 3-v.nng -angled, with 

 deeply excavated sides, stout (0.5-2 m. high), the 

 upper sheath bearing a triangular leaf or none; 

 spikelets 6-12, closely capitate, ovoid, obtuse, over- 

 topped by the short involucral leaf ; scales orbicular, 

 smooth, the inconspicuous mucronate point shorter 

 than the scarious apex : anthers with a vei-y short and blunt 

 minutely bearded tip ; style 2-cleft ; bristles 6, scarcely equaling 

 the narrowly obovate plano-convex and mucronate achene. — Salt 

 marshes, N. H. to Fla. ; also in Mich., and on the Pacific coast. 

 July-Sept. (W. I.) Fig. 288. 

 15. S. mucronAtus L. Resembling the last, 3-9 dm. high ; involucral leaf 

 divergent; spikelets numerous in a dense cluster, oblong-ovoid; scales ovate, 

 mucronate, firm, scarcely at all scaricus ; style S-cleft; 



287. S. Torre vi. 



288. S. Olneyi. 



achene unequally trigonous, broadly 



single 



obovate. 

 probably 



-In a 

 introd. 



locality in Delaware Co., Pa 

 from s. Eu. 



16. S. etuberculatus (Steud.) Ktze. Cuhn (1-2 m. high) 

 ^-angled, usually sharply so above, obtusely below, the 

 sheath at base extended into a long slender triangular and 

 channeled leaf; involucral leaf similar (1-2.5 dm. long), 

 continuing the culm ; spikelets cylindric (1-2 cm. long), 

 single or sometimes proliferously 2 or 3 together, nodding 

 on the apex of the 5-9 long filiform and flattened peduncles 

 or rays of the dichotomous umbel-like corymb, or the 

 central one nearly sessile ; scales loosely imbricated. 

 oblong-ovate, acute, pale, thin and scarious. with a green- 

 ish nerved back; bristles 6, Jirm, furnished above with 

 spreading hairs rather than barbs, equaling the slender 

 abrupt beak of the obovoid-triangular shining achene 

 (4 mm. long). (S. Canbyi Gray; S. cylindricusBrhum.) 

 — Swamps and ponds, Md. to Fla., etc. June-Aug. 

 Fig. 289. 



289. S. etuberculatus. 



