viii Preface 



majority of the herbaceous flowering plants, 

 though some of the largely represented but less 

 striking groups such as the Grasses, Sedges, 

 and Willows have been entirely omitted, 

 not seeming of sufficient general interest to 

 warrant the space required for their intelli- 

 gent treatment. The species are -arranged in 

 accordance with their scientific relationships, 

 with keys to the genera and a general key 

 to the families. Among the illustrations 

 herein contained, many of the plants of 

 the Northwest are figured for the first time. 

 Acknowledgment is here made to Messrs. 

 David McNicoll, Robert Kerr, and other 

 officials and employees of the Canadian 

 Pacific Railway Company through whose 

 courtesy was made possible the gathering of 

 the data for the basis of this work. 



S. B. 



ACADEMY OP NATURAL SCIENCES, 



PHILADELPHIA, October 28, 1907. 



