10 A^inals Entomological Society of America [Vol. XII, 



between the Rocky Mountains and the Sierra Nevadas, and 

 thus includes northern Arizona, California east of the Sierras, 

 Nevada, eastern Oregon and eastern Washington, Utah, parts 

 of Wyoming, the lowlands of Idaho, and reaches its northern 

 limit in the Okanagan Valley in eastern British Columbia. 

 Certain portions of this fauna also break through the mountain 

 barriers on the west and thus extend themselves. South 

 of Mt. Whitney a portion passes through the Walker Basin 

 in company with the more typical Sonoran and extends into 

 the San Joaquin Valley. Another portion runs westward from 

 Modoc and Lassen Counties and passing north of Mt. Shasta, 

 invades the northwestern part of Siskiyou County. The 

 insects of this fauna are generally derivatives of the true 

 Sonoran so not sharply differentiated. The jejunas group of 

 the genus Platynus, Agrilus walsinghami Cr., and the hairy 

 group of Eleodes are perhaps as characteristic as are any 

 Coleoptera that we have in the subfauna. 



That other southern fauna, the one which comprises the 

 greater portion of the insect population of the southern part 

 of California, is not a derivative of the present Sonoran. It is a 

 fauna which has come to us directly from the south through 

 Lower California and presumably in earlier times from lands 

 farther to the south. It is very old and very distinct, having 

 many genera and the bulk of its species totally different from 

 those of the Sonoran. It came into California long before the 

 Sonoran did and consequently is more thoroughly established 

 in southern and middle California. The species are now some 

 of the most characteristic within the state and the fauna as a 

 whole is so dominantly Californian that it might be called the 

 Californian fauna. It is now to be found not only throughout 

 all of Southern California west of the San Bernardino and 

 Sierra Madre Ranges, but along the coast to San Francisco, 

 throughout the more southern portion of the Coast Range, and 

 the greater part of the San Joaquin and Sacramento Valleys, 

 extending as far north as Shasta County. In the drier parts 

 of the state, it is therefore even more dominant than the 

 Sonoran and it sends many of its characteristic forms well 

 within that claimed by the Vancouveran and Sierran as in the 

 foothill regions of the more northern Coast Range and the 

 Sierra Nevada itself, thus sharing equally with the faunas of 

 northern origin, the possession of the land. At one time, the 



