TERTIARY FAUNAS OF THE PACIFIC COAST 227 



Summary and Conclusions 

 Summary 



Cycles of diastrophism 



Periods of maximum elevation and subsidence 

 Changes in climate 

 Diastrophic provinces 



INTRODUCTION 



This paper was presented as part of the symposium on " Correla- 

 tion" arranged by Mr. Bailey Willis as the principal subject for 

 discussion in Section E of the American Association for the Advance- 

 ment of Science, and later continued as the main feature of a special 

 section of the Geological Society of America, at Baltimore during 

 Convocation Week, 1908. The paper treats in a general way of the 

 character and distribution of the sediments laid down, and the faunas 

 and the conditions prevailing during the Tertiary period on the 

 Pacific Coast of North America, more especially that portion lying 

 between Puget Sound on the north and the Gulf of California on the 

 south. The discussion is also restricted almost exclusively to the 

 territory directly affected by the sea, as a detailed consideration of the 

 conditions and faunas prevailing inland belongs more properly 

 within the province of the paleobotanist and vertebrate paleontologist. 

 Special attention is called at several places throughout the discussion 

 to the extraordinary localization of many of the earth-movements 

 affecting the region under discussion and the writer wishes to advance 

 this localization of phenomena as an argument against the too free 

 use of diastrophism, unsupported by paleontologic evidence, as a 

 basis of correlation. 



The preparation of the paper has necessitated the correlation of 

 the various Tertiary formations of the Pacific Coast — in fact the paper 

 is obviously based on these correlations — and for that reason a general 

 table of correlation is here included for reference. Lack of space 

 prevents a discussion of the reasons for many of these correlations. 

 Some of them differ from those previously published by the writer,' 

 but for the most part they are those usually accepted by West Ameri- 

 can geologists and paleontologists. 



> Jour. GeoL, Vol. X, 1902, p. 137; Mem. Cal. Acad. Set., Vol. Ill, 1903, p. 13; 

 U. S. Geological Survey Prof. Paper 47, 1906, p. 10; U. S. Geol. Survey Bull. 30Q, 1907, 

 p. 143; ibid., 321, 1907, p. 21; ibid., 322, 1908, p. 27. 



