Chas. D. Walcott, 



U. S. Geol. Survey. 



<m 





>/w«AJotr«v, 



VOL. XLVIII. * OCTOBER, 1894 



Established by BENJAMIN SILLIMAN in 1818. 



T II E 



AMEEICAN 



JOURNAL OF SCIENCE. 



EDITOES 



JAMES D. and EDWARD S. DANA. 



ASSOCIATE EDITORS 



Professors GEORGE L. GOOD ALE and JOHN 

 TROWBRIDGE, of Cambridge. 



Professors H. A. NEWTON, A. E. VERRILL and 

 H. S. WILLIAMS, of New Haven, 



Professor GEORGE F. BARKER, of Philadelphia. 



THIRD SERIES. 



YOL. XLVIII— [WHOLE' NUMBER, CXLVIIL] 



No. 286.— OCTOBER, 1894. 



NEW HAVEN, CONN.: J. D. & E. S. DANA. 

 1894. 



TUTTLE, MOREHOUSE & TATLOR, PRINTERS, 371 STATE STREET. 



Published monthly. Six dollars per year (postage prepaid). $6.40 to foreign sub- 

 scribers of countries in the Postal Union. Remittances should be made either by 

 money orders, registered letters, or bank checks. 



