North American Cyjyeracece. 247 



Tribe I. CYPEREiE. 



Flowers perfect. Spikelets distichously imbricated 

 (rarely in a spike imbricated on all sides), mostly naked, one 

 or many-flowered. Perigynium none, or setaceous, or cup- 

 shaped. Interior scales growing to the rachis of the spike- 

 let, sometimes becoming free, or altogether wanting. Nut 

 compressed or triangular, rarely rostrate or crowned with the 

 persistent base of the style. 



A. With a Perigynium* 



1. DULICHIUM, Richard. 



Spikelets compressed, distichously imbricated, many- 

 flowered. Bristles of the perigynium 6 — 9, rigid, retrorsely 

 hispid. Stamens 3. Style very long, bifid at the sum- 

 mit. Nut compressed, linear-oblong, acuminated by the 

 long persistent style. — Culm terete, leafy; leaves short and 

 spreading; spikes axillary, compound, with the spikelets dis- 

 tichously arranged on a common rachis. — Richard in Pers, 

 sy7i. 1. p. 65; Nutf. gen. 1. p. 35; Lestib. ess. fam. Cyp. p. 

 37. no. 40 ; N. ah Esenb. in Linnaa, Q. p. 283. Schceni sp. 

 Vahl, &c. Cyperi sp. Linn. 



DuLiCHiuM SPATHACEUM, Pcrsoon. 



Pers. syn. I. c. ; Pursh, /. 1. p. 53 ; Elliott, sJc. 1. p. 73. t. 

 2. /. 3 ; Torr.! fl. 1. p. 58 ; Darlingt.! fl. Cest. p. 9. ed. 2. 

 p. 17; Beck! hot. N. 6f M. St. p. 4^2; Gray! N. Amer. 

 Gram. Sf Cyp. part 2. no. 131 ; Spreng. syst. 1. p. 194. 



Schoenus spathaceus, Linn, sp. ed. 2. p. 63. 



S. anguslifolius, Vahl, enum. 2. p. 225 ; Ram. <f Schult. syst. 2, 

 p. 71. 



Scirpus spathaceus, Michx.! fl. 1. p. 32. 



Cyperus spathaceus, Linn. syst. p. 84 ; Willd. sp. 1, p. 289 ; MukU 

 gram. p. 26 ; Big. fl. Bost. ed. 2. p. 19. 



Cyp. racemis simplicibus lateralibus, &c. Gron. Virg. ed. 1. p. 131. 



Vol. III. 32 



