Flora of the Pacific Coast 

 Here the most prominent species is Castilleia min- 

 iata the numerous red spikes of which impart a 

 rich warm color to the vegetation. Next in import- 

 ance are the white heads of Selinum, which overtop 

 all else save where the clumps of lupine (Lupinus 

 polyphyllus) carry their blue racemes still higher. 

 On one gentle southerly slope the elephant heads 

 (Pedicularis attollens) are very conspicuous and the 

 whole meadow is punctuated with the white spikes 

 of the Sierra rein-orchis (Habenaria leucostachys). 

 More than twenty other species in addition to the 

 grasses and rushes also inhabit this meadow. 



Comparatively dr^ meadows and grass-land are 

 also frequent, affording excellent opportunity for 

 researches upon the relation of environment to dis- 

 tribution and structure. 



The riparian and bog formations have each their 

 characteristic species, but mention can be made only 

 of the California pitcher plant (Darlingtonia cali- 

 fornica). This noted insectivorous species grows in 

 boggy meadows of northern California and southern 

 Oregon. It may be most conveniently examined at 

 the **18th crossing," a few miles south of Sisson on 

 the San Francisco and Portland line of the Southern 

 Pacific Railroad, or in Butterfly Valley, just south of 

 Keddie on the line of the Western Pacific Railroad. 

 The plants are much finer and more abundant at 

 this latter locality. 



Passing over the Canadian and Hudsonian zones 

 we may now take a brief survey of the flora above 

 timber-line. The Arctic-Alpine zone, the lower limit 

 of which is marked by timber-line, scarcely occurs 

 in southern California. On southerly slopes it be- 

 gins at an average altitude of 11,000 feet in the 

 southern Sierra Nevada, at 9500 feet on Mount 

 Shasta, and at about 6500 feet in Washington. 

 Throughout its whole extent the vegetation and the 

 flora are fairly uniform. In this zone all plants have 

 deep perennial roots and low tough stems. The 

 leaves, closely huddled near the base or along the 

 short stems, are heavily cutinized. Among the char- 

 acteristic species, all of boreal origin, may be men- 

 tioned the Arctic willow (Salix arctica var. pefraea) 

 with stems only two or three inches high; Cassiope 

 mertensiana with thick overlapping leaves and 

 dainty pendant flowers; the Alpine sorrel (Oxyria 

 digyna), well known in Arctic and Alpine districts 

 around the world; Polemonium eximium, with 

 showy blue flowers (replaced in Washington by 

 P. elegans), and a number of Composites, mostly 

 with yellow flowers. This is only the beginning of 

 a long series of species which might be enumerated. 



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