240 University of California PiihlicaUons in Geology [Vol. 12 



over the California region, and to permit comparison between the 

 Pacific Coast province and other areas of the world. The absence of 

 adequate maps prevented extensive use of stratigraphic criteria, and 

 it was clear that progress in geological study of the sedimentary for- 

 mations of California would be impossible without full data concern- 

 ing the palaeontological sequence of typical sections. Whitney's view 

 of this question seems to be expressed by his inclusion of two volumes 

 of palaeontology in the three representing his Report of the Geo- 

 logical Survey of California. In a later volume, on the Auriferous 

 Gravels of California, published by Whitney, considerable emphasis 

 is again placed upon the palaeontological aspect of the work. 



The first volume of the Palaeontology of California, published in 

 1864, included a study of the Carboniferous and the Jurassic, by F. B. 

 Meek, and a description of Triassic, Cretaceous, and Eocene faunas,. 



W. M. Gabb. Considering that this work was of the pioneer type 

 and executed within tlie three years following the beginning of the 

 survey, we must grant that it was a most excellent contribution to the 

 faunal study of North America. Volume 2, published in 1869, is 

 another very important contribution, representing entirely the work 

 of Gabb, and including a wide range of faunas from the Cretaceous 

 to the later Cenozoic. Barring the unfortunate confusion of the Cre- 

 taceous and the earlier Eocene, the work of Gabb must be considered 

 as a model, upon which improvement in method and form have scarcely 

 been made in later publications originating in this region. 



The conclusion of the State Geological Survey work, luider the 

 hand of Gabb, furnished for the California region an excellent 

 palaeontological series, beginning with a somewhat scanty fauna of the 

 Carboniferous and ranging through to the Pleistocene. To many it 

 appeared that the invertebrate series of California had already been 

 rounded out, and that later studies, though shifting lines here and 

 there, would not greatly alter the fundamental conclusions reached by 

 Gabb and Whitney. This publication, taken with tlie earlier studies of 

 Conrad, did undoubtedly furnish the major outlines of palaeontological 

 sequence for invertebrate faunas. Later studies have shown that lines, 

 may be moved slightly up or down; that generic and specific descrip- 

 tions may be modified ; that biological and geological classifications 

 must be altered through further subdivision ; and that significant addi- 

 tions must be made. I believe, however, that too great praise cannot 

 be given to the students of this pioneer period for the large measure of 

 result coming from comparatively few years of work, under conditions. 



