LIFE AREAS 291 



ern part), and San Joaquin Valley (southern part), may be 

 called the Sacramento Fauna. The comparatively small area of 

 Lower Austral Zone in the southwestern part of the State may 

 be called the San Diego Fauna. In the eastern part of the State 

 is a large area of arid plain, studded with small barren mountains, 

 known as the Mojave Desert. It is principally Lower Austral 

 Zone, but has a few tracts sufficiently elevated to reach the Upper 

 Austral, and a few very small areas of Transition Zone. This 

 area north of the low Colorado Desert and west of the bottom 

 lands of the Colorado River may be called the Mojave Fauna. 



The Sub-Tropical Zone in California is confined to the bot- 

 tom land along the Colorado River and west in the Colorado 

 Desert, which is properly a part of the same bottom lands. 

 Among the birds which do not breed above this zone, and are 

 found in this part of California are the Harris Hawk, probably 

 the Audubon Caracara, Elf Owl, Vermillion Flycatcher, Abert 

 Towhee and Cooper Tanager. This part of the Sub-Tropical 

 Zone may be called the Colorado Valley Fauna. 



