North American Cyperacece. 257 



linear, very long. Style slender, 3-cleft. Nut acutely triangular, punc- 



tate. 



Hab. In wet places, particularly in river swamps of the 

 Southern States; South Carolina, Elliott!; Georgia, M^ih- 

 lenherg ; New Orleans, T. Drummoncl! and Dr. Ingalls! 



Obs. This species is also a native of South America, the 

 East and West Indies, and Africa. 



9. Cyperus bipartitus. 



Spikelet solitary, appearing lateral, ovate-oblong, many- 

 flowered ; involucre mostly one-leaved, or with an additional 

 short setaceous bract ; scales ovate, rather obtuse and coriaceous; 

 stamens 2 ; style cleft nearly to the'base ; nut biconvex, obovate, 

 obtuse, with a papillose surface. 



Annual. Cuhii triquetrous, 4 — 6 inches high, with two setaceous 

 leaves at the base. Spikelet about 14-floweretl, half an inch long, 2^ 

 lines wide, appearing to grow from the side of the culm about an inch 

 and a half below the summit, but really terminal and subtended by the 

 involucre, which is commonly one-leaved and erect, sometimes two- 

 leaved, the second leaf being short and subulate. Rachis naked. Scales 

 closely imbricated with appressed points, a sharp keel and 5 pale ferru- 

 ginous sides. Style, in the mature flower, cleft nearly to the base, the 

 divisions thicker than in most Cyperi. Nut tumid, dark-brown, dull, 

 covered with minute papillae. 



Hab. Near New Orleans, Dr. Ingalls ! 



Obs. This species resembles C. mucronatus, Linn, in many 

 respects, but the latter is distinguished by having usually several 

 spikelets on each culm, a smooth plano-convex nut, and long 

 compressed style bifid only at the summit. It is not improbable, 

 however, that our plant sometimes beai's more than one spikelet. 



10. Cyperus tenellus, Limi. ? 



Culm and leaves setaceous ; spikelet solitary, appearing la- 

 teral, lanceolate-linear, 10 — 12-flowered ; involucre mostly 



