vi PREFACE. 
above named; especially, his First Lessons in Botany, in which 
the general principles of Botany and Vegetable Physiology are 
fully explained. 
I acknowledge with gratitude the kindness of those friends and 
correspondents who have, in various ways, aided me in my labors. 
To the Rey. Moses A. Curtis, of North Carolina, to whom I 
am permitted to dedicate this volume, especial acknowledgments 
are due, for valuable information derived from a long and instruc- 
tive correspondence, for the generous contribution of new and rare 
specimens, and for important assistance rendered me in every part 
of my work. 
To PROFESSOR Asa Gray, of Harvard University, I am under 
peculiar obligations; not only for the privilege of consulting his 
valuable library, and his extensive ‘herbarium, which contained 
many plants previously unknown to me, but also for the benefit of 
his advice in all matters of doubt and difficulty, and for innumer- 
able aets of kindness, bestowed in every way. 
To Mr. Dantet C. Eston, of New Haven, who is making the 
Ferns a subject of special study, I am greatly indebted for this 
first and very careful elaboration of the Southern plants of that 
interesting family. ; 
I embrace the opportunity to say to those who have aided me 
hitherto, that, if they will continue to favor me with their discov- 
eries, I indulge the hope of preparing a future edition of this work, 
which shall be more worthy of their approbation. 
APALACHICOLA, FLORIDA, March 26, 1860. 
