V'^OL. I MAECH, 1921 



Established by BENJAHm SILLIMAN in 1818. 



THE Z' 



{ MAR-7lS2r 



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. COE and 



FREDERICK E. BEACH, of New Haven, 



Professor EDWARD W. BERRY, of Baltimore, 

 Drs. FREDERICK L. RANSOME and WILLIAM BOWIE, 



OF Washington. 



FIFTH SERIES 



VOL. I— [WHOLE NUMBER, CGI]. 

 No. 3— MARCH, 1921. 



NEW HAVEN, CONNECTICUT. 



19 21. 



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Published monthly. Six dollars per year, in advance. $6.40 to countries in the 

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Entered as second-class matter at the Post Office at New Haven, Conn., under the Act 

 of March 3. 1879. 



