Chas. D. Walcott, . 
U. S. Geological Survey. ; 
= SRE ee MARCH, 1887. 
Established by BENJAMIN SILLIMAN in 1818. 
THE 
AMERICAN 
_|JOURNAL OF SCIENCE 
EDITORS 
JAMES D. anp EDWARD S. DANA. 
ASSOCIATE EDITORS 
Prorrssors ASA GRAY, JOSIAH P. COOKE, anp 
JOHN TROWBRIDGE, or Campripax, 
Prorgessors H. A. NEWTON ann A. E. VERRILL, or 
New Haven, 
Prorzssorn GEORGE F. BARKER, or PHILADELPHIA. 
THIRD SERIES, 
VOL. XXXIII.—[WHOLE NUMBER, CXXXIII.] | 
No. 195—MAROH, 1887. 
NEW HAVEN, CONN.: J. D. & H. 8. DANA. 
1887. 
TUTTLE, MOREHOUSE & TAYLOR, PRINTERS, 371 STATE STREET. 
TT EE ET OT POTTED ELLIE IS TE PLETE LET EDP EES 
Six dollars per year (postage prepaid). $6.40 to foreign subscribers of countries in 
the Postal Union. Remittances should be made either by money orders, registered 
letters, or bank checks, 
