BOTANY. 25 



Description. A tree of moderate size ; foliage evergreen ; leaves oblong-lanceolate, pointed, 

 scarcely acute, reticulately veined ; peduncles ; axillary simple ; flowers numerous, involucred ; 

 fruit roundish-elliptical. 



The &quot; California laurel&quot; forms the handsomest dicotyledonous tree within the limits of the 

 State. The foliage is dark green and lustrous, and persistent throughout the year. The tree, 

 as generally seen, is of small size, twenty to thirty feet in height, and rather inclined to form 

 groups of several individuals. It has very much the general appearance of the European 

 laurel, (L. nolilis,) and is quite as ornamental. 



It is said to attain, in some parts of California and Oregon, much greater dimensions than 

 any individuals which I saw, and to form a very elegant and imposing tree. 



The leaves, when ruhbed or burned, give out a strong aromatic odor, which excites sneezing. 

 The residents of California are very cautious about burning the plant, more especially the 

 leaves, as it is said that a vapor is driven from them by the fire in the highest degree injurious. 

 Of this there is,, however, much doubt. 



The fruit, which is accurately represented (half size) in the figure, is not usually globular, 

 as has been stated, but somewhat elongated and elliptical. All that I saw was green or green 

 ish yellow, but it is said to become purple when ripe. 



FRAXINUS OREGONA. The Oregon ash. 

 F. OREGONA. Nutt. Sylv. 3, p. 59. 



This forms a low spreading tree, which grows commonly along the banks of the Columbia. 

 I also saw it on several occasions on tributaries of the Sacramento, in the upper part of the 

 Sacramento valley. 



I never saw it attaining a greater size than a foot in diameter by thirty to forty feet in height. 



ALNUS OREGONA. The Oregon alder. 

 A. OREGONA. Nutt. Sylv. 1, p. 28, t. 



The Oregon alder forms a tree sometimes of fifty to sixty feet in height, and is generally 

 distributed throughout northern California and Oregon. Like other species of the genus 

 growing along the banks of streams, its form is upright and handsome, and the trunk some 

 times two feet in diameter near the ground. 



The leaves are thicker, and, in large trees, smaller than those of A. viridis or A. serrulata. 

 The wood is brittle, and not to my knowledge employed for any useful purpose. 



POPULUS TREMULOIDES. The quaking aspen. 

 P. TREMULOIDES. Miclix. Flor. Amer. 2, p. 243. 



The aspen grows throughout all parts of the region east of the Cascade mountains and Sierra 

 Nevada which we visited. It forms a marked feature of the vegetation of the slopes of these 

 mountains where the forests of the higher lands border the sage plains of the central desert. 

 It is here seen in long lines of trees of small size, marking the courses of the many mountain 

 streams which are in summer absorbed by the arid surfaces of the plains soon after leaving the 

 mountain sides. For a time we were often deceived by the poplars and willows, regarding 

 them as indications of the presence of water, but we soon learned that they were only a sign 

 that water was to be found in their vicinity at some time during the year. 



Alders we found to be much better guides to water, as they will only follow the courses of 

 the streams just so far as they are permanent, and no further ; and we never failed, even near 

 the close of the dry season, to find the roots of the alders washed by living water. 

 4Z 



