Vi PREFACE. 
The uses of the natural arrangement i abridging the labor of 
acquisition and aiding the memory of the learner are most im- 
portant, and its advantages to cultivators, to physicians,—to 
all who are seeking to enlarge their knowledge of the useful 
or dangerous properties of plants, that they may be able to 
avail themselves of the one. or counteract the other, to gain ma- 
terials for the arts, or remedies or antidotes in medicine, are too 
many to entunerate and too obvious to be further insisted upon. 
In the Conspectus, or Distribution into Families and Genera, 
I have attempted to offer a substitute, so far as the plants treat- 
ed of in this Report are concerned, for the arrangement by the 
artificial system. This attempt I submit with many misgivings. 
If it shall be considered a failure, it may at least serve to aid 
others in more successfully accomplishing the object. 
My sketches of the natural families, and, in a considerable 
degree. of the genera, are necessarily drawn mostly from books; 
and. as they are taken from the standard works of the science, 
Endlicher, Lindley, Torrey, and others, are usually given with- 
out particular acknowledgment of the source. LBotaimsts will 
here, however, find some points touched upon which have not 
usually received much attention from scientific writers. 
The descriptions of the species of all the trees, and nearly all 
the shrubs, are my own, except where I have expressly given 
eredit to others. To collect my materials, I have scoured the 
forests in almost every part of the State, from the western hills 
of Berkshire to Martha's Vineyard, and from the banks of the 
Merrimack to the shores of Buzzard’s and Narragansett Bays. 
The leisure of several summers was first spent in ascertaining 
what the ligneous plants of Massachusetts are, and how they 
are distriluted. If I have not discovered néw species, I have 
found new localities for several oaks, willows, poplars, pines, 
and birches, and some others of less importance, and have thus 
enlarged the Flora of the State. That some species have escaped 
me is altogether probable, as, even in the summer of 1845, I found 
the Red Birch growing abundantly on a branch of the Merrimack, 
some hundreds of miles further north than it had previously 
becn noticed by any botanist. 
After having become familiar with the trees and their local- 
