CYPERACE^E. (SEDGE FAMILY.) 555 



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

 almost bristle-shaped, channelled; umbel simple, 4-S-rayed; spikes 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. filicti.lmis, Vahl. Culm slender, wiry, often reclined (8' -15' 

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

 dense head, or in 17 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. MARfSCUS, Vahl. Style 3-clefl: 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 of 3. ( Perennials with clustered small tubers at base of the culms, 

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



19. C. Lancastri6nsis, 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 reflexed, 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-bracted 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-^ayed ; spikes (50-100) in a globular very dense head, 2-4-flowered, oblong, 

 blunt (l"-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. retrofractUS, 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, 1 - ^.-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. KYLLINGIA. (PL 1.) 



Spikes of 3 or 4 two-ranked scales, 1 - Ij-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. pumila, Michx. Head globular or 3-lobed, whitish-green (about 

 4" broad) ; spikes strictly 1-flowered; 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. 



