PREP VCE. 

HE idea has been long entertained, of collecting the 
Natural Productions of Chester County, with special 
reference to the elucidation of its Prospective History. With 
this object in view, THE CABINET OF NATURAL SCIENCE OF 
CHESTER COUNTY was organized, in the year 1826. From 
that time forward, several of its members engaged, with 
ardor, in the work. But it was soon discovered that the 
field for research was too ample —the labor too great — the 
laborers too few, for this destderatum to be speedily attained. 
Yet, much has been accomplished. 
The indefatigable industry, and scientific acumen, of the 
late Doctor William Darlington, has left little more to be 
done, in Phenogamous and Filicoid Botany, within our 
limits. His little FLoRULA C@srrica appeared in 1826. It 
was followed, eleven years after, by the more extended, and 
complete, FLora Castrica. ‘This was greatly enlarged, and 
improved, in a ¢hird edition, in 1853. It was also rendered 
more comprehensive, by the addition of the remaining 
Anophyta (the Mosses and Liverworts) furnished by Zhomas 
P. James; and the Thallophyta (the Lichens and Collemas) 
by Dr. E£. Michener. 
ix 
