North American Ci/jteracem. 20-5 
iOiizoma creeping extensively ; the branches often terminating in tubers 
about the size of a large pea. Culm 12 — 18 inches high, acutely trian- 
gular. Leaves a little recur\-ed, 2 — 3 lines broad, strongly carinate, 
smooth, yellowish. Umbel rather erect ; the rays 2 — 4 inches long, 
without involucels. Involucre mostly 3-leaved. Spikelets three-fourths 
•of an inch long, linear, somewhat obtuse when mature, for the most part 
distichously arranged on the common rachis, the lowest ones frequently 
geminate or fasciculate. Scales yello-v^-ish, nerv^ed, at length distinct at 
the point. Interior scales lanceolate, adnata, hyaline. Staniens 3. Style 
sometimes unequally 3-cleft. Nut acute. 
Hab. Wet sandy places, particularly on the banks of rivers, 
and on the sea shore ; western part of New York to New Orleans. 
Common on the sea coast of Long Island and i^ew Jersey, and 
on the Hudson as far north as Newburgh ! ; near Oneida Lake, 
New York ; Pennsylvania, North Carolina, and Georgia, 
Muhlenhurg ! ; S. Carolina, Elliott and Mr. Forbes!; New 
Orleans, Dr. Ingalls ! ; Delaware and East Florida, Dr. 
Baldioin ! 
Obs. The tubers or thickened extremities of the subter- 
ranean stems are edible, but are inferior in size to those of the 
C. tuberostis of Vahl, with which Pursh confounded our plant. 
Dr. Baldwin, in his notes, states that this species is the " Nut- 
grass" of East Florida, where it covers cultivated fields, and is 
much more common than C. Hydra. He remarks that he found 
the same plant on the banks of the river Plata, near Buenos 
Ayres. 
Muhlenberg's Cyperus, No. 9, is a mere variety of C. 
repens. 
18. Cyperus Hydra, Mickaux. 
Rhizoma creeping, tuberiferous ; umbel simple, 3 — 4- 
rayed ; involucre a little longer than the ray ; spike, distichous ; 
spikelets 4 — 5 on each ray, lanceolate-linear, acute, much com- 
pressed, 14 — 20-flowered ; scales ovate, approximated, some- 
what spreading, rather acute, appressed, nerveless, not scarious 
on the margin ; nut triquetrous. 
