Okdeb 155.— OTPKRACE^. 735 



« 

 12 to 40-flowered, loosely aggregated in heads; rachis winged; glumes ovate, 

 slightly veined, acuminate, yellowish, very acutely keeled ; etam. 3 ; ach. obovate, 

 3-angled, shining. — Dry fields, S. States. Spikes 6 to 12" long, sharply serrated 

 by the projecting points of the glumea Root fibrous. 



23 C. denta.tus Toit. Culm about If high, leafy at base, triquetrous; Ivs. a little 

 shorter than the stem, strongly keeled ; umbel compound, 6 — 10-rayed; invol. 

 of 3 unequal leaves, one of them longer than the umbel ; spikes 3 on each pedvmck, 

 3 — 7", lance-ovate, flat, 8 (rarely 5 to 30) flowered; glumes acute, spreading at the 

 points, giving the spikes a serrated appearance; sty. 3-cleft; ach. triangular. — U 

 Swamps, Mass., to W. T. and Fla. Rhizome creeping, bearing tubers. Spikes 

 often morbidly enlarged. 



24 C. Iiec6ntii Torr. Culm 3-angled 1 to 2f high, leafy at base ; Iva. linear, 

 about the same height ; invol. 3 to 6-lvd., longer than the umbel ; umbel com- 

 pound, many-rayed; spikes oblong, obiMse, flat, in small digitate clusters, 20 to 40- 

 flowsred; glumes closely, imbricated, acute, yellowish, the points obtttsish, caUous, 

 scarcely separated ; stam. 3. — Ha.! to La. An elegant species. Spikes 4 to 7" 

 by 2"- Rhizome creeping. 



25. C. leptos Schultes. Culm weak, 1 to 2f high, 3-angled ; Ivs. radical, shorter ; 

 umbel compound or decompound, of numerous (12 to 15) filiform rays, with a short, 

 t-leaved involucre; spikes 3 to 5 in each loose head, lance-linear, 12 to 20-flow- 

 ered ; glumes ovate-lanceolate, acute, keeled, the keel green, sides yellow with 2 

 red lines. — Damp soils, N. Car. to Fla. and La. Spikes 3 to 4" long. Sept., 

 Oct. (C. graoihs Muhl.) 



26 C. ovularis Tahl. Culm acutely 3-angled, nearly naked, 6 to 16' high; Ivs. 

 shorter, nearly smooth; umbel simple; rays 3" to 2' long; hds. 1 to 5, globular, 

 one sessile, the rest on the spreading rays; spikes linear-subulate, 3" long, 50 to 

 100 in each head ; fls. 2 to 4, 1 or 2 fertile ; iuvoL 3 or 4-leaved, outer Ivs. very 

 long; glumes ovate, obtuse, greenish, the two lowest empty. — Bogs and low 

 grounds, M, "W. and S. States, common. Aug., Sept. (Marisous Tahl. Kyl- 

 lingia Mx.) 



27 C. retrofr£ctu3 Yahl. Culm obtusely triangular, nearly leafless, pubescent, 2 

 to 3f high ; Ivs. pubescent, 3 to 4" wide, about half as long as the stem ; umbels 

 simple ; rays unequal, long, G to 8 ; invol. 3 to 5-leaved ; bracts unequal, not 

 longer than the rays; spikes 70 to 100, subulate, 1-flowered, finally retrorsely im- 

 bricate into obovate heads ; 2 lower glumes empty. — Mid., W. and S. States, rare 

 northward. Aug., Sept. 



3. KYLLIN'GIA, L. (In honor of Peter Kylling, a Danish botanist.) 

 Spikes compressed ; scales about 4, the 2 lowest short and empty, the 

 third only usually with a fertile flower ; stamens 1 to 3 ; style long, 2- 

 cleft ; achenia lenticular. — Sts. triangular. Hds. sessile, solitary or ag- 

 gregated, involucrate. 



1 K. plimila Mx. Csespitous ; culm 2 to 12' high, slender ; Ivs. mostly radical, 

 shorter than the stem, smooth ; hds. generally solitary, sometimes triple, closely 

 sessile, oval or oblong ; invol. 3-leaved, 1 to 2' long ; spikes 1-flowered, very nu- 

 merous, about 2" long ; the lowest glume or glumes very small ; sta. always 2 ; 

 ach. lens-shaped, fulvous. — ^Wet hanks, Columbus, Ohio (Sullivant) to IlL (Lap- 

 ham) and S. States. Variable. Aug. K. sesquiflora Torr. is a taller form, with 

 . triple heads. (Florida, Chapman.) 



4. FUIRE^NA, Eotboll. Clot-grass. (In honor of George Fuiren^ 

 a Dutch botanist.) Glumes imbricated on all sides into a spike, awned 

 below the apex ; petaloid scales 3, cordate, awned, unguiculate, invest- 

 ing the achenium, which is abruptly contracted to a stipe at base. — if 

 St. angular, leafy. Spikes umbeled or capitate, axillary and terminal. 



1 F. Bquarr6sa Mx. Culm 1 to 2f high, obtusely triangular, .sulcate ; Ivs. flat, 

 oiliato, shorter than the stem; sheaths hispid-pilous; spikes clustered, ovoid,- 

 mostly terminal, 7 to 12; avms nearly as long as the glumes; petals ovate, ouapi- 



