V*-. 



282 



THE AURIFEROUS GRAVELS OF THE SIERRA NEVADA. 



with general credence, would place man in Europe in the Tertiary as 

 decidedly as does the Calaveras skull in America. Among these the bril- 

 liant investigations of Ribeiro and the Geological Survey of Portugal ought 

 to be mentioned, as an excellent illustration of the way important discov- 



eries 



backed up by an abundance of evidence 



are ignored, when not 



fitting in with the preconceived ideas of the majority.* 



It will be expected by many that the epoch of the Tertiary at which 

 man made his appearance in California, or, at least, in which he can earliest 

 be recognized as having existed, should be stated as definitely as possible. 

 This is by no means an easy thing to do. The divisions of the Tertiary into 

 Pliocene, Miocene, etc., as originally instituted by Lyell, were based on the 

 relative abundance in the different groups of the shell-bearing mollusca, and 

 far more on those of marine than on those of fresh-water origin. To co- 

 ordinate strata thus classified with others which contain only the remains 

 of land animals is, of course, a very unsatisfactory proceeding. Indeed, the 

 divisions of the Tertiary in any region ought not, in the nature of things, to 

 be strictly comparable to those in another somewhat distant one. In the 

 upper part of the geological series animal life begins to be differentiated 

 according to zonal position and climatic conditions, hence general classifica- 

 tions of the Tertiary become vague and often even misleading; yet so con- 

 venient are they, that it will probably be long before they drop out of use. 

 As one of the consequences of the use of Lyell's names for the Tertiary 

 there is no representation of the Eocene in California ; or, at least, none 

 which can be distinctly recognized as such. Yet, no doubt, while Eocene 

 rocks were being deposited in other parts of this country, and in other more 

 distant regions, some accumulations of sediment were being formed, and 

 some kind of animal or vegetable life existing on the Pacific slope. 



* See DescripcTto de alguns Silex e Quartzites lascados encontrados nas Camadas dos Terrenos Ter- 

 ciario e Quaternario das Bacias do Tejo e Sado. Lisboa, 1871. In this memoir Ribeiro shows that cut 

 flints, evidently the work of human hands, have been found in abundance in the Pliocene and Miocene, 

 even' of Portugal ; that there are more than 1,200 feet, of strata piled over the beds containing these im- 

 plements ; that these rocks have been upheaved and turned up at an angle in places quite vertical, since 

 man's appearance ; and that this appearance was prior to the cessation of volcanic activity in that region, 

 so that the human race must have witnessed those grand dislocations of the earth's crust to which the 

 present topographical features of that part of Portugal, are due. Yerneuil himself was obliged to admit 

 that there was every reason for calling these strata Tertiary, except that they contained proofs of the exist- 

 ence of man at the time of their deposition. Lyell does not even mention the Portuguese discoveries in 

 the last edition of his " Antiquity of Man," published in 1873, two years after the appearance of Ribeiro's 



memoir. i n 



The important investigations made in India, by the officers of the Geological Survey, have been equally 

 ignored by Lyell ; they seem to show, beyond doubt, the immense antiquity of the human race m that 

 country. ' These results were published several years before Lyell's last edition was issued. 



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