BOTANY. 19 



the Cascades, at this point, were collected ahout fifty minor flowering plants, some of peculiar 

 interest. Of these, Menziesia empetri/ormis, Saxifraga Tolmcei, and Pentstemon Menziesii, cov- 

 ered large surfaces with their flowers, and, with the gentians, recalled the heaths and other 

 alpine plants of the Old World. 



The Cascade mountains, in the vicinity of the Columbia, are covered with a forest similar in 

 character to that which I have described, but in which by far the largest number of trees are 

 Douglas' spruce and the western balsam fir. Here, as on the coast mountains, where the 

 forests have been burned off, the ground is covered with a rank growth of Pteris aquilina. The 

 banks of the Columbia, along the water's edge, are lined with cotton-woods, and in some places 

 with Garry's oak. 



The lower part of the Willamette valley is occupied by the densest forest which I saw at the 

 west, composed principally of Douglas' spruce, here known as the red fir, the western balsam 

 fir, called by the inhabitants the white fir, the hemlock spruce, and arbor vita3. Of dico- 

 tyledonous trees almost the only ones are the large leafed maple, the vine maple, {Acer 

 circinata,) and Cornus Nuttallii. The upper part of the valley consists, for the most part, 

 of prairie, covered with a luxuriant growth of grass, while the borders of the streams are 

 lined with oaks, as in the Sacramento valley. The annual vegetation, which is quite varied, 

 includes a large number of species found in California, with others better suited to a more 

 northern latitude and a moister climate. 



