VOL. I 



JUNE, 1921 



Established by BENJAMIN SILI^MAN in 1818. 



h^JUN -2 i92i 



4^; 



THE 



£^ona! ^^^ 



i<^'. 



AMERICAN 



JOURNAL OF SCIENCE 



Editor: EDWARD S. DANA. 



ASSOCIATE EDITORS 



Professors WILLIAM M. DAVIS and REGINALD A. DALY, 



OF Cambridge, 



j Professors HORACE L. WELLS, CHARLES SCHUCHERT, 

 i HERBERT E. GREGORY, WESLEY R. COE and 



i FREDERICK E. BEACH, of New Haven, 



! 



i Professor EDWARD W. BERRY, of Baltimore, 



! Drs. FREDERICK L. RANSOME axd WILLIAM BOWIE, 



OF Washington. 



FIFTH SERIES 



VOL. I— [WHOLE NUMBER, CCI]. 

 No. 6~JUNE, 1921. 



NEW HAVEN, CONNECTICUT. 



1921. 



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