with the subject and being engaged in other work, I then suggested 
to Mr. Ewan that he undertake to revise the manuscript in view of 
much monographic work which has appeared since. This he has done, 
rewriting and editing much of it and preparing the text for the ferns 
and the introductory paragraphs, save the general description of the 
vegetation. It is clear, therefore, that whatever merit may be as- 
signed the paper is due to his careful revision; the shortcomings, I 
fear, are my Own. 
Apart from acknowledgments which are made elsewhere, I wish 
to express my indebtedness to the late Howard Flint, to Mr. J. H. Christ, 
to Mr. R. R. Humphrey, and to Mr. Wm. Rockie, all of whom have very kind- 
ly read the description of the vegetation and have offered valuable 
suggestions concerning it. I am especially indebted to the latter, 
who first led me to see trees, as well as the forest; he was one of 
my most valued teachers. I wish also to express my appreciation to 
Mr. Gerhardt Kempf, who, particularly upon one bng tramp through the 
St. Joe and Clearwater Forests, aided me greatly by his knowledge of 
the forest. 
For identification of specimens in critical groups, the 
authors are under lasting obligations to many specialists. Dr. W. R. 
Maxon has assisted with the Pteridophyta, except Isoetes, for which 
we are indebted to Pr. Norma L. Pfeiffer and to Dr. E. B. Copeland. 
Both Mr. K. K. Mackenzie and Mr. J. W. Stacey have generously read 
the typescript of Carex, the late Mr. Mackenzie determining the col- 
lections. Mr. Jason R. Swallen contributed in its entirety the ex- 
