22 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



mediate in position, have generally escaped the notice that they 

 have deserved. Aside from the brief reference by Antisell in 

 the Pacific Railroad Reports, there are only meager accounts 

 of their geology or paleontology to be found in the literature 

 of California geology. 



Among these lower Miocene localities are those in northern 

 San Luis Obispo County, as well as the locality on Los 

 Vaqueros Creek, Monterey County, from which the name 

 "Vaqueros Formation" has been derived. The additions here 

 made to the lower Miocene fauna of California come from a 

 more exhaustive study of these deposits, and of those on the 

 Kern River along the eastern border of the Temblor Basin. 

 In no other part of the province of geology is the value of 

 intensive stratigraphic work and of invertebrate paleontology 

 as an aid, more clearly disclosed than in the systematic study 

 of the marine oil-bearing formations of California. It is not 

 difficult for the paleontologist familiar with these horizons and 

 their faunas, to follow or identify them in districts outside of 

 productive fields, and thereby in some measure judge of the 

 merits of untried areas. Much of the pioneer development 

 work of the oil districts of this state has been guided con- 

 sciously or otherwise by "fossil shells", even by unscientific 

 operators. 



In a systematic study of the various deposits, economic and 

 other, that belong to the Pacific Coast Tertiary, there are not 

 only practical and local problems, but there are problems of 

 provincial, regional, or even continental extent that require 

 consideration, and which can not be overlooked by the philo- 

 sophic student who would correctly understand his data. For 

 this purpose it would be desirable to know much about the 

 climatic conditions of the Tertiary, and the environment of its 

 local faunas. Too little attention has hitherto been given to 

 these and similar phases of West Coast geology. 



However, it is not the purpose to undertake an extensive 

 discussion of stratigraphy, faunas or climate in the present 

 paper, but merely to suggest the subjects, which, it is hoped, 

 will be further treated hereafter and incidentally to introduce 

 into the literature a few of the hitherto undescribed inverte- 

 brate species in advance of subsequent discussions. 



