Monograph of North American Rhij/uhosjwne. 219 
ing as if surrounded with a thickened margin, smooth, obovate, very 
broad at the summit, attenuate at the base as if raised on a short stipe. 
Tubercle subulate, compressed, as long as the nut. 
Hab. Pine barrens of New Jersey and on Long Island about 
Babylon, Torreij ; Wilmington, N. Carolina, Mr. Curtis; 
Georgia, Le Conte; New Orleans, Dr. Ingalls ; Gadsden 
County, Middle Florida, Dr. Chapman. 
Obs. This interesting species was discovered by Prof. Torrey 
several years since, in the pine barrens of New Jersey and 
on Long Island ; and as in these locahties it occurs, for the 
most part, with only two heads, it received the name of R. 
biceps. Our specimens from the southern states, however, 
have uniformly more than two heads, and often six or seven. 
I have therefore ventured to substitute for the manuscript 
name of Professor Torrey, one which is in a good degree 
characteristic of the habit of the species. This plant is 
very closely allied to R. gJomerata, but is much larger and 
stronger in all its parts. Its larger and margined nut, and its 
more ample, and for the most part, spherical heads, will suf- 
ficiently distinguish it from that species. A most remarka- 
ble circumstance with regard to this species, and so far as 
my observation extends, peculiar to it, is the diversity in the 
direction of the hispidness of the bristles : even in different 
individuals from the same cluster some of the bristles are 
hispid upward and others downward. With this single 
exception, the direction of the hispidness of the bristles is, in 
each species of this genus, perfectly constant. 
I Species inquirenda. 
Scheenus axillaris, " culmo triquetro, folioso ; corymbis minimis, altemis, 
axillaribus; spiculis confertis." Lam'k. El. Gen. I. p. 137. 
Hab. Carolina, D. Fraser. — Lamarck. 
