Preface.. 
All the territory of the United States of America soutb of the 
British boundary, except Oregon Washington and Idaho, being 
supplied with local Floras this work is intended to fill up the 
corner left out by other authors. 
As the writing of descriptions of plants at this late date is, to 
a great extent, writing or copying what others have previously 
done, it is hardly right to claim originality for work do: e in ‘hat 
field; I, therefor, wish to acknowlege that I have used the works 
of Torrey & Gray, Dr. Asa Gray, Sereno Watson. William 
Trelease Coulter & Rose, Edward L. Greene and others, amd tor 
save repetition (which would otherwise occur on every page) 
I wish to give full credit here to all authors, any portin cf 
whose works have been copied herein. 
Wherever possible descriptions have been drawn from speci- 
mens in hand, tut some I have been unable to procure and for 
these I have had no other alternative than to cepy frem descrip- 
ions already published. 
Believing that if a plant has on+ cons‘ant character that is 
different from any of its cogeners it is sufficient for a species; and 
that if a plant is sufficiently distinct from others to deserve a 
name it is tetter to have it described as a distinct s;ecies than 
as a variety of some other species, I have therefor, ra‘sed 
nearly all published varieties cf the region em! raced in this work 
to spacific rank. | 
