£30773 
Introduction 
This book was written primarily on account of the imperative need for it in our own 
classes at the University of Washington. Geographically it covers Oregon, Idaho, 
Washington and the southwest corner of British Columbia; and it includes only the 
flowering plants. The aim has been a book complete for a large area, with complete 
keys based so far as possible upon easily determined characters, with common names, 
and with as much description as possible without exceeding a textbook price. In the 
names the attempt has been to vary as little as possible from other northwestern books, 
believing that uniformity is far more important than rules of precedence in names. Wher- 
ever we have had to choose we have leaned toward the classification in Engler and Prantl, 
and toward the Vienna code. 
This book is not a research work, but an attempt to make usable a part of what is 
already known. We have made use of other books, of pamphlets, and of journals, 
whenever we have found them useful. Among the books found most helpful we mention 
the following in alphabetical order: Coulter & Nelson’s “New Manual of Rocky Moun- 
tain Botany,” Engler & Prantl’s “Die natiirliche Pflanzenfamilien,”’ Howell’s “Flora of 
Northwest America,” Piper’s ‘Flora of the State of Washington,’ Robinson & Fernald’s 
“Gray’s New Manual of Botany.” 
Following the genus descriptions is given the origin or meaning of the generic name. 
In this we received assistance from Dean A. S. Haggett (Greek) and Prof. David Thom- 
son (Latin) of the University of Washington; but for any errors in these, as in other 
portions of the book, we assume all responsibility. ‘That it is free from errors is not a 
reasonable hope, on account of the vast multitude of minute details of fact, as well as 
arrangement. 
To illustrate the use of the keys let us take the common large-leaved maple. Be- 
ginning on page 5 with the Key to the Families, compare A with AA; evidently this 
maple falls under AA. Compare the next letter (C) under AA with its double (CC) ; 
this maple goes to CC, which refers to the Key to the Dicotyledons on page 7. There 
compare A with AA, to find it goes to A; then the first letter (B) under A with its 
double (BB), tracing it to BB; likewise thru the C’s and D’s to the family ACERACEAE, 
page 249. There comparing with the family description, whose chief characteristics are 
in italics, it is found to agree. Since there is only | genus (ACER) in this family, it 
follows directly, with the common name (MAPLE) of the group to the right. Compar- 
ing the plant with the genus description, short in this case, it is found to agree. Under 
it compare A with AA, tracing it to A; compare then B, BB, BBB, finding it goes 
to BB. Then follows W. C. E., which gives its distribution (See abbreviations, p. 4) ; 
then A, macrophyllum, the scientific name. In this, A, is the abbreviation of the genus 
name, ACER, and macrophyllum is the species name. This is followed by “‘Pursh,”’ 
the name of the man who named this plant. “‘Large-leaved Maple” foliows, and is the 
common name of this particular maple. The scientific name is often preceded by synonyms 
in italics. 
‘Ter GouF RYE: 
G.- Ba Rice 
