Library, U. 3. INat. Museum. 



VOL. Ill 



JANUARY, 1922 



Established by BENJAMIN SI. 



AMER 



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. Ill— [WHOLE NUMBER. CCIII], 

 No. 13 -JANUARY, 1922. 



WITH TWO PLATES. 



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