^diy, u.j. iviat. Museum. 



VOL. XLVIII 



OCTOBER, 1919. 



Established by BENJAMIN SILLIMAN in 1818. 



THE 



AMERICAN 



JOURNAL OF SCIENCE 



Editor: EDWARD S. DANA. 



ASSOCIATE EDITORS 



Professors GEORGE L. GOODALE, JOHN" TROWBRIDGE, 

 and WM. M. DAYIS, op 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, CXCVIII]. 



No. 286— OCTOBER, 1919. 



NEW HAVEN, CONNECTICUT. 



19 19. 



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