*tibrary, U. S. Nat. Museum. 



VOL. XLVJII 



Mm k A I r > Jii I i, I 



Established by BENJAMIN SILLIMAN in 1818. 



THE 



AMERICA 



JOURNAL OF SCIENCE. 



Editor: EDWARD S. DANA. 



ASSOCIATE EDITORS 



Professors GEORGE L. GOODALE, JOHN TROWBRIDGE, 

 and WM. M. DAVIS, of Cambridge, 



Professors A. E. VERRILL, HORACE L. WELLS, CHARLES 



SCHUCHERT, L. V. PIRSSON, H. E. GREGORY, 



and HORACE S. UHLER, of New Haven, 



Professor JOSEPH S. AMES, of Baltimore, 

 Mr. J. S. DILLER, of Washington. 



FOURTH SERIES 

 VOL. XLVIII— [WHOLE NUMBER, OXCVIII], 



No. 287— NOVEMBER, 1919. 



NEW HAVEN, CONNECTICUT. 



1919.- 



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

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