A Monograph of the North American species of 
Rhynchospora. By Asa Gray, M. D. 
Read December, 1834. 
The natural order Cyperace^ has, in proportion to the 
number of species it comprises, been less carefully studied than 
any other family of phenogamous plants. Notwithstanding the 
researches of R. Brown, Kunth, Nees von Esenbeck, &c. 
who have illustrated particular portions of this family, the distinc- 
tive characters of the genera are, in many cases, highly unsatis- 
factory, and the determination of species is frequently difficult. 
The whole order requires an elaborate revision by some com- 
petent person, who can consult the principal herbaria of pre- 
ceding botanists, as well as many important works, which, from 
their great cost or extreme scarcity, are inaccessible to us. — 
But the plants of any single country may be most advanta- 
geously studied by a botanist who is familiar with them in their 
native situations, and who has opportunities of examining and 
comparing with each other numerous specimens from various 
localities. 
A person who in this way confines his attention, for a time 
at least, to the critical examination of a single genus or family 
of plants, and who carefully records the facts which he ob- 
serves, may furnish important materials to those who, with 
more ample means, are to succeed him in the same field ; and 
thus contribute, in some degree, to the advancement of the 
cause of science. 
The following account of the North American species of 
Rhynchospora has been prepared under circumstances highly 
favourable for arriving at correct results. With a liberality 
which does honour to the cause in which they are engaged, my 
botanical friends have placed their collections at my disposal 
Vol. III. 25 
