North American Cyperacece. 255 
6. CyPERUS MICRODONTUS. 
Umbel with short crowded rays, or sessile ; spikes numerous, 
lanceolate-linear, about 14-flowered; scales deciduous, ovate, 
rather acute, submembranaceous ; stamens 2 ; style deeply 2- 
cleft ; nut oblong-obovate, obtuse ; rachis denticulate with the 
inner scales. 
" C. brizseus ?" Schweiniiz ! in litt. 
Annual. Culm cespitose, 2 — 4 inches high, triangular. Leaves a 
line and a half broad. Umbel sessile, or with several rays scarcely half 
an inch long. Involucre 4 — 5-leaved. Spikelets half an inch in length, 
12 — 16-flowered, alternate on the common rachis. Scales spread- 
ing but closely imbricated, indistinctly striate; the keel narrow and 
rather obtuse, green ; the sides pale yellowish-brown ; margin not sca- 
rious. Interior scales persistent, giving the rachis a denticulate appear- 
ance when the primary scales have fallen. Stamens always 2. Style 
cleft more than half way down. Nut rather tumid, dark-gray, dull, 
minutely dotted under a strong lens. 
Hab. Salem, North Carolina, Schweiniiz! 
Obs. This species does not appear to have been hitherto 
described. It cannot be the C. brizceus of Richard, which has 
oblong-ovate spikelets. I have only received it from Mr, 
Schweinitz. 
7. Cyperus Gatesii. 
Umbel of many (6 — 8) distinct rays ; spikelets somewhat 
distant, alternate (with the lower ones fasciculately compound), 
linear-lanceolate, 10 — 12-flowered ; scales oblong-lanceolate, 
rather acute, loosely imbricate, submembranaceous ; stamens 
2 ; style deeply 2-cleft ; nut oblong-obovate, obtuse ; rachis 
with a narrow margin. 
Perennial. CuZm nearly a foot high, slender, obtusely-triangular. 
Leaves narrow, pale green ; those of the involucre about three in number. 
Rays of the umbel very unequal, 4 or 5 of the longer ones about 2 inches 
Vol. III. 33 
