VOLUME XX NUMBER 3 - 
THE 
JOURNAL or GEOLOGY 
A SEMI-~QUARTERLY 
EDITED BY 
THOMAS C. CHAMBERLIN AND ROLLIN D. SALISBURY 
With the Active Collaboration of 
SAMUEL W. WILLISTON ALBERT JOHANNSEN WILLIAM H. EMMONS 
Vertebrate Paleontology Petrology Economic Geology 
STUART WELLER WALLACE W. ATWOOD ROLLIN T. CHAMBERLIN 
Invertebrate Paleontology Physiography Dynamic Geology 
ASSOCIATE EDITORS 
_ SIR ARCHIBALD GEIKIE, Great Britain GROVE K. GILBERT, Washington, D.C. 
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. 
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 
ORVILLE A. DERBY, Brazil WILLIAM H. HOBBS, University of Michigan 
T, W. EDGEWORTH DAVID, Australia FRANK D. ADAMS, McGill University 
BAILEY WILLIS, Argentine Republic CHARLES K, LEITH, University of Wisconsin 
APRIL-MAY, 1912 
CONTENTS 
MUSER MEIN CUACIATIONS -. 0. =) 8  Watter Howcuin 102 
__ THE VALUE OF CERTAIN CRITERIA FOR THE DETERMINATION. OF THE ORIGIN 
OF FOLIATED CRYSTALLINE ROCKS:-P == 9s s-). oJ; Di Trueman 228 
SILICEOUS OOLITES AND OTHER CONCRETIONARY STRUCTURES IN THE 
VICINITY OF STATE COLLEGE, PENNSYLVANIA - = Exwoop S. Moore 259 
BEL MROLOCICAL ABSTRACHS AND (REVIEWS =. 20s 92 7 78 oe ve ee Oyo 
ESB VTRTEN RS ce ores aed SU ae i 0 a sl alg Sk lagna al ype aa 
Che University of Chicago press 
~ CHICAGO, ILLINOIS 
AGENTS: 
THE CAMBRIDGE UNIVERSITY PRESS, Lonpon anp EDINBURGH’ 
WILLIAM WESLEY & SON, Lonpon 
TH. STAUFFER, LEIPZIG 
THE MARUZEN-KABUSHIKI-KAISHA, Tokyo, OsaKa, Kyoto 
