Vlii EDITOR'S PREFACE. 



the troublesome plants of the West, which have been acknowledged in 

 the proper places. I am also indebted to I. A. LAP HAM, Esq., for his 

 offer, which came too late to be available, to furnish notes upon the 

 weeds of Wisconsin. The more important illustrations in the work are 

 from original drawings, by ANTHONY HOCHSTEIN, Esq., whose delicate 

 sketches have hardly justice done them by being rendered in wood. The 

 most of his drawings are designated by his initials. The remainder of the 

 engravings were obtained from the best available sources. My friend, 

 Mr. FRANK A. POLLARD, has rendered me most essential aid, both be- 

 fore and during the rapid printing of the work, which I would gratefully 

 acknowledge. 



Where new observations or other matter has been added, or the old 

 ones essentially modified, a * has been appended. This, however, has 

 been omitted where the alterations are unimportant ; in these cases any 

 faults may be placed to the account of the editor. 



NEW YORK, January Sist, 1859. 



