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hae EDITED BY f @ 56 42 
ee THOMAS C. CHAMBERLIN AND ROLLIN D. SALISBURY . Nas 0 
r: With the Active Collaboration of ~ ‘onal Museu. ~ 
C SAMUEL W. WILLISTON ALBERT JOHANNSEN WILLIAM H. EMMONS Ci 0 
Vertebrate Paleontology Petrology Economic Geol ian Jn: 7 
STUART WELLER WALLACE W. ATWOOD ROLLIN T. CHAMBE HSOMlAh MNStify, 
Ss Invertebrate Paleontology Physiography Dynamic y 
’ ASSOCIATE EDITORS 
f? SIR ARCHIBALD GEIKIE, Great Britain GROVE K. GILBERT, Washington, D.C. ae 
4 HEINRICH ROSENBUSCH, Germany CHARLES D. WALCOTT, Smithsonian Institution 
THEODOR N. TSCHERNYSCHEW, Russia HENRY S. WILLIAMS, Cornell University 
__ CHARLES BARROIS, France JOSEPH P.IDDINGS, Washington, D.C. 
2 _ ALBRECHT PENCK, Germany JOHN C. BRANNER, Leland Stanford Junior University 
HANS REUSCH, Norway ; RICHARD A. F. PENROSE, Jr., Philadelphia, Pa. 
_ GERARD DeGEER, Sweden WILLIAM B. CLARK, Johns Hopkins University 
4 ORVILLE A. DERBY, Brazil WILLIAM H. HOBBS, University of Michigan 
_ TT, W.EDGEWORTH DAVID, Australia FRANK D. ADAMS, McGill University 
zs BAILEY WILLIS, Argentine Republic CHARLES K, LEITH, University of Wisconsin 
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Tee JANUARY-FEBRUARY 1913 
i | THE SECONDARY ENRICHMENT OF SILVER ORES - ~~~ - «H.C. Coxe 
Be THE GEOLOGY GraeGN Pt) 8 ee 2 Waren Dy Smad, Pa De) 220 
PRELIMINARY NOTES ON SOME IGNEOUS ROCKS OF JAPAN - - - S. Kézu 62 
THE QUIZZYHOTA BABOGUTER vo si ef Scere ee 
i AN ACCESSORY LENS FOR OBSERVING INTERFERENCE FIGURES OF SMALL 
ae es _ MINERAL GRAINS Be SSO eR ROT A Ee eh ea AER ORANINEER ° (.Q6 
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THE UNIVERSITY OF CHICAGO PRESS 
rs CHICAGO, ILLINOIS, U.S.A. 
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Br AGENTS > 4, 
Be THE CAMBRIDGE UNIVERSITY PRESS, Lonpon anp EpinsurcH je eas . 
J WILLIAM WESLEY & SON, Lonpon s Pe Lddings | 
Brey . TH. STAUFFER, Lerezic COLLECTION 2 
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+? THE MARUZEN-KABUSHIKLKAISHA, Toxvo, Osaka, Kyoro ations) mused 3 
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