142 W. S. Cooper 



doubtful specimens and uncertain references have been rigor- 

 ously excluded. 



Valuable information has come to me through correspondence 

 with Dr. R. F. Griggs, of George Washington University; Dr. 

 Eric Hulten, of Lund, Sweden; Miss Isobel W. Hutchison, of 

 Carlowrie, Kirkliston, Scotland; Dr. W. L. Jepson, of the Uni- 

 versity of California; Dr. W. L. G. Joerg, of the American Geo- 

 graphical Society; Dr. H. M. Raup, of the Arnold Arboretum 

 of Harvard University; and Dr. Vilhjalmur Stefansson, of New 

 York City. 



Compilation of data has been done under my direction by 

 Miss Faith E Hall, Miss Dorothea Fritz, and Mr. Frank E. 

 Egler. Mr. Egler prepared most of the maps. It is a pleasure to 

 acknowledge financial assistance given to me by the Graduate 

 School of the University of Minnesota. 



GENERAL SURVEY 

 The coastal province which constitutes the field of this study 

 extends from southeastern Alaska to Socorro, Baja California. 

 The southern limit merely marks the end of the territory that I 

 have personally explored. There are no adequate data for extend- 

 ing the survey farther. Within this province, consideration has 

 been stricdy confined to the flora of the strand and dunes. 



Without attempting a detailed ecologic analysis, we may 

 divide the vegetation of these habitats into two communities, 

 which will serve equally well as units for floristic study. One 

 community inhabits the actual strand or upper beach and the 

 areas of moving and accumulating sand, particularly the fore- 

 dunes; the other occupies the surfaces of stabilized dunes. 



The first is distinctively maritime and will receive the larger 

 share of our attention. Selection of species is an easy matter be- 



