The Fournal of Geology 
Published on or about the following dates: February 1, March 15, May 1, June 15, 
August 1, September 15, November 1, December 15. 
Vol. XX CONTENTS FOR MAY-JUNE, 1912 No. 4 
DYNAMIC RELATIONS AND TERMINOLOGY OF STRATIGRAPHIC CONFORMITY AND UNCONFORMITY 
W. O. CrosBy 289 
THE VALUE OF CERTAIN CRITERIA FOR THE DETERMINATION OF THE ORIGIN OF FOLIATED 
GRYSTALUINE ROCKS. Il 5 ee, ee a Je Da DemewAn dec 
AN OCCURRENCE OF COAL WHICH BEARS EVIDENCE OF UNUSUAL CONDITIONS ACCOMPANYING 
ITS DEPOSITION. .-) =). Zi ied aches sono uens lost elanio Miaeien othe pants ig ESSESE Eee MegTe 
THE GEOLOGY OF SOUTH MOUNTAIN AT THE JUNCTION OF BERKS, LEBANON, AND LANCASTER 
COUNTIES “PENNSYLVANIA )0 crab a anisole (a ea Nees Se a2) LN EATON a 3t 
MURAENOSAURUS? REEDII, SP. NOV. AND TRICLEIDUS? LARAMIENSIS KNIGHT, AMERICAN JUR- 
IASSIG PLESIOSAURS (ry) ou lech ee a) eee ee Maurice G, Mirna 
METAMORPHIC STUDIES m=) 980) ee eee eee 2 CK Ler AnpeWatp Mieamnees 
PETROLOGICAL ABSTRACTS*AND REVIEWS © 92" (220) 80 er 
REVIEWS - - TE LE OEE Ze OD UR ENS RINE ys Oh een RE ARC IAS AES 6a 3 
RECENT, PUBLICATIONS) .\. cil)? Gen ec siemens sare Suleirs, gut lee atl chain ordi ee nels, MENON banana esta 
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