VI Phytogeographie Survey of North America. Preface. 
plains, the Piedmont, the Atlantic coastal plain, as far, as extreme southern 
Florida and the Floridan keys, the Dismal Swamp, ‚the White, Green, 
Adirondack, Catskill, northern and southern Appalachian mountains. With 
the object of leaving in permanent form a description of the native vege- 
tation of North America, various herbaria in Philadelphia and elsewhere have 
been consulted and correspondence was begun with botanists in various 
parts of the continent, interested in a phytogeographic, or a systematic study 
of the flora. A large collection of books and pamphlets has been made, 
including articles taken from weekly and monthly magazines, and these have 
been classified for instant use during the prosecution of a work which the 
author has spared no pains to make as accurate, as the existing state of in- 
formation and the unfortunate confusion in nomenclature would permit. Details 
of synonomy, omitted in the lists and in a discussion of the plant formations, 
are given in the index, while the more important typographic blunders are 
given proper place. 
A collection of photographs, maps and printed illustrations pertinent to 
American phytogeography has been made during the last few years, and these 
will be arranged and bound in book form for the future reference of students 
of American vegetation, when its original state will then be a matter of 
historic record. 
he author wishes to thank most cordially the botanists and scientific 
friends who have aided him in his work. Many of the societies and individuals, 
who have given assistance, are mentioned in the bibliography, in the text, 
and in the footnotes of the illustrations and printed pages throughout the book. 
Especially, he desires to mention the financial aid given in the printing of the 
book by the American Philosophical Society out of the Michaux Fund, which as 
a legacy left to the Society by the French botanist, FRANGOIS ANDRE MICHAUX, 
has done much to advance the study of arboriculture and for the purchase of 
botanic books for the library begun by BENJAMIN FRANKLIN. 
Finally the author wishes to acknowledge the encouragement and help 
received from the editors, Professors A. ENGLER and OÖ. DRUDE, and the 
publishers who have allowed the book to exceed its original limits. He wishes 
especially to thank Professor Dr. OsCAR DRUDE, who has given much of his 
time to the revision of the work, while in manuscript and in the press, ably 
assisted by his daughter Miss HILDEGARD DRUDE (now Mrs. ROBERT HOHLFELD) 
in the final proof reading of the English text. 
University of Pennsylvania 
Philadelphia, October 21, 1910. 
John W. Harshberger. 
