248 North American Cyperacees. 
Cyp. culmo tereti, (kc. Gron. Virg. ed. 2. p. 9. 
Gram, junceum, elatia=, &c. Pluk. aim. 279. /. 301./. 1. 
Cuhn about 18 inches high, terete below, obscurely triangular above , 
smooth. Leaves linear, flat, 2 — 3 inches long, 2 — 3 lines wide, acute, 
spreading almost horizontally in three directions ; sheaths rather loose, 
truncate, brownish and naked at the throat. Sj}ikes or racemes on short 
exserted peduncles, growing from the sheaths of the leaves, each bearing 
from 8 to 14 lanceolate-linear, distichously spreading spikelets, about 
three-fourths of an inch long. Partial rachis flexuous, 6 — 10-flowered, 
articulated, easily separating at the joints, which are excavated by the 
pressure of the nuts. Scales lanceolate, very acute, appressed, yellow- 
ferruginous with a green keel. Bristles seldom less than 7, and often 9, 
(16 Vahl!) strong and rigid, persistent, projecting a little beyond the 
scale when mature, longer than the nut without the style. Stamens 3; 
filaments verj' slender, longer than the bristles, arKl inserted within them 
at their base. Style attenuated into a long point, bifid at the extremity, 
smooth. Nut about a line and a half long, smooth and dull, light brown , 
contracted into a short pedicel at the base, flat at the back, and a little 
convex in front, the summit tapering into a long, straight point, formed of 
the inarticulate, persistent, undivided style. 
Hab. Borders of ponds, and in swamps, from Canada ! to 
Georgia and Pennsylvania ! and west to the Mississippi. — Au- 
gust to kjeptember. 
I have seen in the herbarium of my friend John Carey, 
Esq. a specimen of this plant, in which most of the nuts were 
in the stale of Ergot ; a disease which very rarely occurs in 
this natural order. 
Obs. The genus Dulichium is very distinct in habit from 
any other Cyperaceous plant growing within the limits of our 
Flora, and there is considerable difficulty in determining the 
true section to which it belongs. In many respects it agrees 
with the Scirpeae, in others with the Rhynchosporeae. It resem- 
bles the Cypereae in the distichous arrangement of the scales ; 
and the spikelets long on the common rachis; but it differs 
from most of them in its rostrate fruit and rigid perigynous 
bristles. 
The D. Canadense of Persoon is probably identical with this 
species, the number of florets in the spikelet being variable. 
