cyperacejE. (sedge family.) 555 



17. C. Grayii, Torr. Culm thread-form, wiry (6'- 12' high); haves 

 almost hr 1st 1 1' -shaped, channelled; umbel simple, 4-6-rayed; sjrikes 5-10 in a loose 

 head, spreading; joints of the axis winged; scales rather obtuse, greenish-chestnut- 

 color. — Barren sands, Plymouth, Mass., to New Jersey, near the coast. 



18. C. filiciilmis, 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 1-7 additional looser heads on spreading rays of an irregular 

 umbel; joints of the axis naked; scales blunt, greenish. (C. mariscoides, Ell.) — 

 Dry sterile soil : common, especially southward. 



§4. MAIltSCUS, Vahl. Style 3-cleft: the achenium triangular: stamens 3: 

 spikes 1 -few-flowered, narrow or awl-shaped, with 2 lower scales short and 

 empty, and inclined to persist on the common axis when the rest of the spike dis- 

 articulates and falls, crowded in dense heads : otherwise nearly as in the penul- 

 timate division o/*§ 3. ( Perennials with clustered small tubers at base of the culms, 

 as in the preceding division: spikes green, merely tawny with age.) 



19. C. Lancastriensis, T. C. Porter, n. sp. Culm (l°-2° high) trian- 

 gular ; leaves rather broadly linear; umbel of 6 - 9 mostly elongated rays ; spikes 

 very numerous in short-oblong or globular dense heads, soon rcflexed, 3-6- 

 flowered, linear-awl-shaped ; the joints of the axis broadly winged ; scales oblong, 

 obtuse, twice the length of the linear-oblong achenium. — Rich soil, banks of the 

 Susquehanna near Lancaster, Penn., Prof. Porter. — Most like the Southern 

 C. Baldwinii, Torr. ; but twice the size ; the more numerous spikes 4" - 5" long, 

 more linear, less pointed, on a setaceous-bractcd axis of 6" or 7" in length, 

 with longer scales and achenium, &c. 



20. C. OVUlaris, Torr. Culm sharply triangular (6'- 12' high); umbel 

 1-6-rayed; spikes (50-100) in a globular very dense head, 2 -4-ftowered, oblong, 

 blunt (H"-2" long) ; joints of the axis winged; scales ovate, obtuse, a little 

 longer than the obovate-oblong achenium. — Sandy dry soil, S. New York to 

 Illinois and southward. 



21. C. r etr of r actus, Torr. Culm and leaves usually minutely downy 

 and rough on the obtusish angles (l°-3° high); umbel many-rayed; spikes 

 slender-awl -shaped, very numerous in obovate or oblong heads terminating the 

 elongated rays, soon reflexed, l-2-flowered in the middle (3" -5" long); scales 

 usually 4 or 5, the two lowest ovate and empty, the fertile lanceolate and pointed, 

 the uppermost involute-awl-shaped; achenium linear. (Scirpus retrofractus, L. ) 

 — Sandy fields, New Jersey to Virginia, and southward. 



2. KYLLINGIA, Rottboll. Ktllingia. (PL 1.) 



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

 and empty, as in Cyperus, § 4, but style oftener 2-cleft, and achenium lenticular : 

 the spikes densely aggregated in solitary or triple sessile heads. Involucre 

 3-leaved. (Named after Peter Kylling, a Danish botanist of the 17th century.) 



1. K. piimila, Michx. Head globular or 3-lobed, whitish-green (about 

 4" broad) ; spikes strictly 1-flowcred; upper scales ovate, pointed, rough on the 

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

 and southward. Aug. — Culms 2' - 9' high : root annual. 



