ii93 North American Cy2)eracf.a. 



times bear short leaves. Spike 12 — 16 lines in length. Scales coria- 

 ceous, with a narrow scarious margin, sometimes a little pointed, often 

 minutely dotted with purple. ^ris^Zes retrorsely hispid, four of them 

 equalling the tubercle. Stamens 3. Style cleft about one-third of its 

 length. Nut rather broadly obovate, somewhat tumid, grayish while, 

 not shining; the surface appearing very finely reticulate under a lens. 

 Tubercle minute, dark brown, articulated to the nut by a very short 

 neck. 



Hab. Swamps and margins of rivers, growing in tlie water. 

 Near Philadelphia, Mr. Steinhaur and Mr. Z. Collins! ; 

 Pomonkey Creek, Maryland, Dr. Tiohhins; near Wilmington, 

 North Carolina, Mr. Curtis! ; Carolina, Michaux! ; near New 

 Orleans, Dr. Ivgalls! 



Obs. This plant, as Michaux correctly remarks, resembles 

 Scirj)us mutatus, Linn. It has also a strong resemblance to 

 S. acutangulus, Roxh. (Limnochloa, N. ah E.) Mr. Elliott 

 states, that in the rice fields of the South, it is a very injurious 

 intruder ; its thick roots occupying the ground, and permitting 

 nothing to grow where they extend. 



"§. 2. Spike cylindrical; scales rigid, arranged in a spiral order ; 

 style 3-cleft ; nut biconvex, twnid; pericarp very thick and 

 spongy ; tubercle conical, spongy, confluent, — Somphocarya. 



3. Eleocharis cellulosa. 



Culm subterete above, obtusely triangular below, with a long 

 truncate sheath ; spike cylindrical ; bristles longer than the 

 nut, nearly smooth ; nut broadly obovate, cellular and reticu- 

 lated, crowned with a broad conical subacute tubercle. 



Culms 2 feet high, 1^^ line in diameter, spongy, invested one third of its 

 length with a single sheath, obscurely 3-sided towards the base, but terete 

 near the spike, scarcely striate. Spike an inch long, obtuse. Scales 

 nearly orbicular, obscurely spiral, pale brown, sometimes dotted with 

 red ; margin distinct, scarious, whitish. Bristles 6, strong, smooth, with 



