20 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Others have made smaller collections of plants in the State. Their 

 names appear in association with the specimens they gathered. 



The writer's personal observations and collections have been made 

 in many parts of the State. Especially extensive collections were 

 made about Seattle, 1885-1892; Mount Rainer, 1888 and 1895; 

 Olympic Mountains, 1890 and 1895; Union City, 1890; Pullman and 

 vicinity, 1893-1903; Blue Mountains, 1896. The earliest of these 

 collections are in the herbarium of the State University at Seattle; 

 the remainder are at Pullman, in the State College of Washington. 

 The herbarium of the State College, which more than any other is 

 the basis of this work, contains about 40,000 sheets of Washington 

 plants, including very full sets of the Washington collections of 

 Howell, Henderson, Suksdorf , Vasey, Sandberg and Leiberg, Gorman, 

 Flett, Whited, Horner, Lake and Hull, Allen, Elmer, Gardner, 

 Lamb, Heller, Cotton, Cotton and Griffiths, Kreager, Mrs. L. A. 

 Bouck, Beattie and Chapman, and Conard. A nearly complete set 

 of the writer's own collections, including the types of his new species, 

 is deposited in the National Herbarium. 



PHYSIOGRAPHY AND GEOLOGY. 



The accompanying relief map (PI. II) will render clear the prin- 

 cipal physiographic features of the State of Washington. It may 

 conveniently be considered to be made up of seven regions, namely, 

 the Pacific Coastal Plain, the Olympic Mountains, the Puget Sound 

 Basin, the Cascade Mountains, the Columbia Basin, the Okanogan 

 Highlands, and the Blue Mountains. 



THE PACIFIC COASTAL PLAIN. 



This is a narrow strip of land in immediate proximity to the Pa- 

 cific Ocean and the Straits of Juan de Fuca. It is watered by 

 numerous short streams from the Olympic Mountains and from the 

 low Coast Mountains in Chehalis and Pacific counties. The largest 

 stream, the Chehalis River, rises in the Cascade Mountains, and its 

 valley connects the coastal plain with the Puget Sound Basin. 



The formation of most of the land is quite similar to that of the 

 Puget Sound Basin, described below. The distinctive features are, 

 first, the low strip of sandy land, seldom over a mile wide, formed 

 by the inland drifting of thcs ocean sand; second, the steep rocky 

 bluffs which face the ocean at the mouth of the Columbia River and 

 in a few places near Cape Flattery, and third, the coastal plain 

 proper. This region is characterized by having a very great rainfall, 

 ranging from 200 to 300 centimeters (80 to 120 inches) annually. 



