IV PREFACE TO THE SECOND EDITION. 



Darlington's " Flora Cestrica." In determining the geographi- 

 cal range of the species, I have derived great assistance from 

 the various local catalogues of plants which have been pub- 

 lished within the last ten years. I have also consulted with 

 much advantage several valuable papers which have from time 

 to time appeared in Silliman's Journal, and in other scientific 

 periodicals. Particular references to the sources of informa- 

 tion will in all cases be found in their appropriate places. 



The favorable reception which this work has met with, and 

 the kind expressions of botanists in various parts of the coun- 

 try, encourage me to hope that this revision will be no less 

 acceptable. 



RUTGERS COLLEGE, N. J. 

 February, 1848. 



