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Freeman and Chandler The World's Com- 

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Penhallow A Manual of the North American 

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UNIVERSITY OF CALIFORNIA 

 PUBLICATIONS 



Tha University of California issues publications in the 

 following series among others I 



Agricultural Science 

 American Archaeology 



and Ethnology 

 Botany 

 Economics 

 Geology 



Memoirs of the University of California 

 Bulletin and Publications of the Lick Observatory 



RECENT TITLES 



Fundamental Inter-relationships between Certain Solu- 

 ble Salts and Soil Colloids, by L. T. Sharp $ 



Species Novae vel Minus Cognitae, by T. S. Brandegee. 



Notes on Some Hemiptera Taken near Lake Tahoe, Cali- 

 fornia, by E. P. Van Duzee 



Mesozoic and Cenozoic Mactrinae of the Pacific Coast of 

 North America, by E. L. Packard i 



Stratigraphy and Fauna of the Tejon Eocene of Califor- 

 nia, by R. E. Dickerson I 



The Correlation of the Pre-Cambrian Rocks of the Re- 

 gion of the Great Lakes, by A. C. Lawson 



Two New Aplodontias from Western North America, by 

 W. P.Taylor 



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PRINCIPLES OF 



STRATIGRAPHY 



BY 



AMADEUS W. GRABAU, S.M., S.D. 



PROFESSOR OF PALAEONTOLOGY IN 

 COLUMBIA UNIVERSITY 



Large Octavo, 1150 pages, with 254 illustrations in the text. 

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