148 



THE DESERT 



Sali-bush, 



The grasses. 



The lichens. 



like a brilliant carpet swayed by the wind. Bui 

 I have not found this floral procession extend- 

 ing down into the lower desert regions. In the 

 wastes of southwestern Arizona, in the Salton 

 Basin and in the low levels that lie about Death 

 Valley the growth is far more limited. Even 

 there one occasionally finds poppies, violets, 

 wild verbenas, patches of evening primrose, or 

 up in the swales the little baby blue-eye or the 

 yellow mimulus ; but all told they do not make 

 up a very strong contingent. The salt-bush 

 that looks the color of Scotch heather, out-bulks 

 them all, and yet is not conspicuously apparent. 

 Nor are there many grasses of consequence 

 aside from a small curled grass and the heavy 

 sacaton that grow in bunches upon isolated 

 portions of the desert. By " isolated " I mean 

 that for some unknown reason there are tracts 

 on the desert seemingly sacred to certain plants, 

 some to cholla, some to yuccas, some to grease - 

 wood, some to sahuaros, some to sacaton grass. 

 It seems to be a desert oddity that the vegeta- 

 tion does not mix or mingle to any great ex- 

 tent. There are seldom more than four or five 

 kinds of growth to be found in one tract. It 

 is even noticeable in the lichens. One moun- 

 tain range will have all gray lichens on its 

 northern walls, another range will have all 



