VI PREFACE 



My obligations, for assistance, extend even beyond the Atlantic.—* 

 To Dr. F. Boott, of London, I owe many acknowledgments for 

 botanical favors, — and especially for his kindness in Aerifying a num- 

 ber of our most obscure and difficult plants, by a comparison with 

 those in the JJnnxan, Banksi an, and other authentic Herbariums, in 

 that city. 



1 have been also favored with books, and many authenticated speci- 

 mens illustrative of North American Botany, by ^ir W. J. Hooker, 

 the accomplished Professor of our Science in the University of Glas- 

 gow, Scotland, — a gentleman whose attention has leen particularly 

 directed to the plants of this hemisphere, — and whoie liberality and 

 urbanity have won the hearts of all American Botanists who have had 

 the pleasure of his correspondence. 



An apology will doubtless be expected from me, for still adhering fo 

 the Linnman arrangement, when the modern botanic.il world have so 

 generally abandoned it for the Natural method. 1 aia fully conscious 

 of the old-fashioned garb in which this work is arrayed, and have a 

 thorough conviction of the value and importance of studying plants 

 according to their natural affinities : But, observing ihat the Natural 

 method is yet kept, as it were, in a continual state of fermentation, by 

 the labors and researches of the great Masters in tie Science, — and 

 feeling my inability to co-operate, or aid in adjusting its details, — I 

 thought it most advisable, in the present attempt, to kdherc mainly to 

 the Linnsan classification. Whilst I freely adnit that the true 

 science of vegetables can only be attained by a well-disciplined and 

 philosophical investigation of their structure, functions, and natural 

 affinities, I cannot help thinking that even the superficial knowledge of 

 genera and species, which is so readily acquired by tLc Linnaean sys- 

 tem, may be advantageous to the cause, by exciting an early interest 

 in learners, and facilitating the first steps of the uninitiated. When 

 the young recruits are once securely enlisted, we miy venture to ex- 

 act a more rigid discipline. In the meantime, a good foundation may 

 be laid for a scientific knowledge of plants, by the study of such ad- 

 mirable elementary works as those of Dn Candolli, or Richard, — 

 and that recently published in our own language, by Dr. A. Gray ; of 

 New York. 



Notwithstanding the arrangement according to the Sexual System 

 is confessedly artificial, the reader cannot fail to remark how many of 

 those great families of plants which arc obviously natural, are yet 

 preserved under it, nearly or quite entire. By doing a slight violence 

 to the Linnsean method (as I have ventured to do, in this work, at the 

 suggestion of my friend, Dr. Pickering), it will be seen that the gen- 

 era belonging to the following eminently Natural Orders, may be all 

 kept together — viz : Cyperacese, Graminese, Boraginex, Umbelliferm y 

 Rosacea, Pomacete, Amygdalex, Labiata, Crucife*ce, Lejrvminosse, 

 Composite, Or chides, Filices, and Lycopodiacex. These orders 

 comprise nearly half the genera, and more than half the species, enu- 

 merated in the present work. In addition to the foregoing, it will be 

 found that the genera (84 in number) belonging to 30 additional Nat- 

 ural Orders, and comprising about 180 species, are all grouped 

 together under the Linmean arrangement ; and a large proportion of 



