/ Library, U. 5. Nat. Museum. 



VOL. Ill 



APRIL, 1922 



Established by BENJAMIN SILLIMAN in 1818. 



THE 



AMERICAS 



JOURNAL OF SCIENCE. 



Editor: EDWARD S. DANA. 



ASSOCIATE EDITORS 



Professors WILLIAM M. DAVIS and REGINALD A. DALY, 



of Cambridge, 



i 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. Ill— [WHOLE NUMBER, CCIII] 

 No. 16— APRIL, 1922. 



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19 22. 



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