Caricography. 319 
been found by later botanists, even in the very localities men- 
tioned by that author. ‘These several species, common in 
Europe, are generally supposed not to inhabit our country. 
The other species in Pursh’s Flora have been introduced 
into this Caricography. f the numerous species in the 
An. Tab. of Dr. Schweinitz, most have been introduced into 
this work, as species or varieties well ascertained. Future 
examinations may detect some mistakes, or discover other 
species, which m may be the subject of another paper. Figures 
of forty-nine species and varieties have been given in this 
work, embracing all the new to which the writer had access. 
By some, there will be thought to be a too great increase of 
species. The present hostility to introduction of new 
species is favourable to the cause of natural science. In hi 
Discourse before the New-York Alpha of the ®. B. K. 
Society, His Excellency DeWitt Clinton expressed the 
ral opinion of scientific men upon this subject. Still it is 
oe aie this principle may, like every other, be carried 
ie extreme, and one which shall be equally 
ital peg science. The natural history of any genus can- 
not be perfect, siti all the _— distinct 
nized and describe 
A 
difference, every trifling variation” is not to constitute a new 
species, the language or practice even of Linnzus will not 
authorize the rejection of important and constant differences. 
Upon them he founded all the species he described. “ Upon 
science is perfected. There can be little doubt that future 
d. 
observers will add many species to those already describe 
Systematic Arrangement and Index of the North American 
Species of Carex 
I. SrTicMAS Two. 
A. Spike single. Diecious. 
1, Carex ete : ond Vol. X. p. 285 
Linnzana, Walt 
Dateline ites i 
2. ‘Wormskoldian,* Hornem. Vol. XI. p. 154 
— scirpord 
— Mich reed chy: | 
* Those species marked with an asterisk are common to. Europe and this 
country. — 
. 
