CATALOGUE OF CALIFORNIAN FOSSILS. 



By dr. J. G. COOPER. 



PART II. BIBLIOGRAPHY AND REFERENCES. 



The pala?ontology of California differs from that of the States north 

 of the Potomac and Ohio Rivers in the existence of more of the Neozoic 

 formations (including Miocene, Pliocene, and Quaternary) than those 

 of older date, showing that the elevation of this coast above the ocean 

 was chiefly since the Mesozoic ages, and much of it took place as late 

 as the Quaternary, or a little before the era of man. 



The consequence of this late uplift is that nearly all the coast 

 ranges and the low foothills of the Sierra are covered by strata, in 

 some places thousands of feet thick, and often containing solid beds of 

 fossils several feet thick, of which the greater part are identical with 

 living species, besides others, of forms similar to those now living 

 farther north or south, but extinct on this part of the coast. 



The most interesting conclusions derivable from these facts are con- 

 nected with the changes of temperature in the ocean currents, which 

 must have occurred during the gradual elevation of the land, indicating 

 a range from tropical to arctic, with various oscillations at intervals, 

 each of which must have existed a long time to allow of the coloniza- 

 tion of species from a long distance, for varying periods of time. 



Other questions of much scientific interest, and perhaps leading to 

 practical results, are connected with the study of these late fossils. 

 Having been the subjects of investigation (in their living forms) since 

 the time of Linnajus, about one hundred and thirty years ago, their 

 descriptions are scattered through numerous books by European and 

 American authors, who have often described the same species under 

 different names, or from distant regions where some of our fossils are 

 also found living. The identification of these descriptions is yet only 

 partly accomplished, and the discovery of living species in a fossil state 

 is still progressing. 



Much was done in this line of study by Mr. Gabb, as published in 

 the "Palaeontology of California," but nearly as much has been dis- 

 covered since. A great difhculty in the study has been the want of a 

 complete catalogue of authors and books, with reference of each species 

 to the first description and figure. The confused and scattered notices 

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