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s. D. Walcott, 



17. S. Geol. Survey. 



— „,..„. .. , ,, 



\ KJLi. A,ju V'iii. 





Established by BENJAMIN SILLIMAN in 1818. 



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Professors H. A. NEWTON, A. E. VERRILL and 

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THIRD SERIES. 

 YOL. XLYI1I— [WHOLE NUMBER, CXLYIIL] 

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 1894. 



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