266 North American Cijperacece. 



in length, and somewhat erect. Spikelets acute, 6 — 8 lines long and one 

 line broad, of a pale-yellowish colour ; the lowest ones on the common 

 rachis a little compound. Partial rachis flexuous, the narrow winged 

 margin formed of the confluent and persistent inner scales. Nut as in 

 the preceding species. 



Hab. Near Mobile, Alabama, Dr. H. Gates! 



Obs. This species resembles C. microdontus in the spikelets 

 and nut, but is otherwise very distinct. I have only received 

 it from the above-named locality. 



§2. Style 3-c^e/i;; nut t?iangular ; interior scales mem- 

 branaceous and adnate to the rachis, not separating in 

 the matU7'e spikelet, sometimes almost wanting.- — Cyperus. 



a. Culm suhterete, nodose. 



8. CVPERUS ARTICULATUS, Li7in. 



Umbel compound, loose ; spikelets long, linear, alternate, 

 approximate ; culm with leafless sheaths towards the base. 



C. articulatus, Willd. sp. 1. p. 270; Michx.lfl. l.p. 27; Pursh, fi. 1. 

 p. 50 ; Muhl.! gram. p. 18 ; Vahl, enu?n. 2. p. 301 ; Kunth, syn. 1. p. 137 ; 

 Ram. 8f Schult. syst. 2. p. 163 ; N. ah Esenb. Cyp. Ind. in Wight's con- 

 trib. p. 80. 



jRhizoma creeping, clothed with large lanceolate scales. Culm 2 — 6 

 feet high, the middle part about as thick as a goose -quill, filled with dry 

 pith, which is condensed at intervals of about an inch, producing false 

 nodes, very conspicuous in the dried plant. Sheaths 2 — 3, clothing 

 the lower part of the culm, and terminating in large, acute, erect 

 scales, rather than leaves. Umbel of five or more primary rays, 2 — 4 

 inches in length ; the rays simple or compound, each division bearing 

 about 10 spikelets. Involucre very short, 2 — 3-leaved. Spikelets an inch 

 long, 15 — 20-flowered, convex on the sides. Rachis distinctly margined. 

 Scales ovate-lanceolate, rather obtuse, membranaceous on the margin ; 

 midrib green; the sides whitish mixed with red. Stamens 2; anthers 



