494 OYPEUACE.E. (SEDGE FAMILY.) 



16. C Cxl'styii, Torr. Culm thread-form, why (6'- 12' high) ; leaves nearly 

 bristle-shaped, channelled; umbel simple, 1-G-rayed; spikes 5-10 in a loose head, 

 spreading, 5-7-flowcred, the joints of the axis winged; scales rather obtuse, green- 

 ish-chestnut-color; aeheniuin obovate, minutely pointed. — Barren sandy soil, 

 Rhode Island to New Jersey, near the coast. Aug. (Approaches the next.) 



17. C lilicEllsBSBS, Vahl. Culm slender, wiry, often reclined (8' -15' 

 high) ; leaves linear (l"-2" wide) ; spikes numerous and clustered in one sessile dense 

 head, or in 1 - 3 additional looser heads on spreaeliug rays, 6 - 10-flowered ; joints of 

 the axis naked ; scales blunt, greenish ; aehenium obovate-, short-pointed. (C. ma- 

 riscoides, Ell.) — Dry sterile soil; common, especially southward. Aug. 



$4. MARlSCUS, Vahl. — Style 3-cleft : the aehenium triangular: stamens 3 

 spikes 1 - few-flowered, scarcely flattened ; the 2 lower scales short and empty : oth- 

 erwise as in § 3. 



18. C. OVUiftl'iS, Torr. Smooth; culm sharply triangular (C -12' high) ; 

 umbel 1-6-raycd; spikes in globular dense heads, 2 - -i-flowered, short and thick: 

 joints of the axis winged ; scales ovate, blunt, greenish ; aehenium obovoid. U 

 (Kyllingia, Michx. ) — Sandy soil, S. New York to Illinois and southward. 

 Aug. - Oct. — Heads barely £' in diameter, of 50-100 spikes. 



19. C. retrof rectus, Torr. Culm minutely downy like the leaves, rough 

 on the obtusish angles (1° -3° high); umbel .many-rayed ; spikes slender, aid- 

 snaped, very numerous in obovate or oblong heads terminating the elongated 

 rays, soon reflcxed, l-2-flowered in the middle; scales usually 4 or 5, the two 

 lowest ovate and empty, the fertile lanceolate, the uppermost involute-awl-shaped; 

 aehenium linear. \ (Scirpus retrofractus, L.) — Sandy fields, New Jersey to 

 Virginia, and southward. Aug'. — Spikes £' long, 50 - 100 in a head, greenish. 



2. KYLLINGIA, L. Kyllingia. 



Spikes of 3-4 two-ranked scales, 1 - 1 ^-flowered ; the 2 lower scales minute 

 and empty, as in Cypcrus § 4 , otherwise as in Cyperus § 1 (viz. style 2-clcft; 

 aehenium lenticular) : but the numerous spikes densely aggregated in solitary 

 or triple sessile heads. Involucre about 3-leaved. (Named after Kylling, a 

 Danish botanist.) 



1. K. ptaiaiila, Michx. Head globular or 3-lobed, whitish-green (4" 

 broad) ; spikes strictly 1-flowercd ; upper scales ovate, pointed, rough on the 

 keel; stamens 2; leaves linear. — Low grounds, Ohio to Illinois, and southward. 

 Aug. — Culms 2' - 9' high. 



3. BIHLICfllUM, Richard. Ddlichium. 



Spikes many- (6 - 10-) flowered, linear, flattened, sessile in 2 ranks on axillary 

 solitary peduncles emerging from the sheaths of the leaves. Scales 2-rankcd, 

 lanceolate. Perianth of 6-9 downwardly barbed bristles. Stamens 3. Style 

 2-cleft above. Aehenium flattened, linear-oblong, beaked with the long persist- 

 ent style.— A perennial herb, with a terete simple culm (l°-2° high), jointed 

 and leafy to the summit ; the leaves short and flat, linear, 3-ranked. (The name 

 of .i Greek island; its application unexplained ) 



