Chas. D. Walcott, 



U. S. Geological Survey. 



jlw. zvo. vol. 2L2LXLV. NOVEMBER, 1887. 



Established by BENJAMIN SILLIMAN in 1818. 



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AMERICAN 



JOURNAL OF SCIENCE. 



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THIRD SEEIES. 



VOL. XXXIV. -[WHOLE NUMBER, CXXXIV.J 



WITH PLATES II TO IX. 



No. 203— NOVEMBER, 1887. 



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