VOL. I APRIL, 1921 



Established by BENJAMIN SILLIMAN in 1818. 



THE ^PR " " 



JOURNAL OF SCIENCE. 



Editor: EDWARD S. DANA. 



ASSOCIATE EDITORS 



Professors WILLIAM M. DAVIS and REGINALD A. DALY, 



OP Cambridge, 



Professors HORACE L. WELLS, CHARLES SCHUCHERT, 



HERBERT E. GREGORY, WESLEY R. COB and 



FREDERICK E. BEACH, of New Haven, 



Professor EDWARD W. BERRY, op Baltimore, 

 Drs. FREDERICK L. RANSOME and WILLIAM BOWIE, 



OP Washington. 



FIFTH SERIES 



VOL. I— [WHOLE NUMBER, CCI]. 

 No. 4— APRIL, 1921. 



NEW HAVEN, CONNECTICUT. 



19 2 1. 



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