PROCEEDINGS 



OF THE 



American Philosophical Society 



HELD AT PHILADELPHIA 



FOR PROMOTING USEFUL KNOWLEDGE 



Vol. L. October-December, 191 i. No. 202. 



CONTENTS. 



The Formation of Coal Beds. II. By John J. Stevenson 519 



Stated Meeting, May 3, igii xtii 



Stated Meeting, October 6, igir xiii 



Stated Meeting, November 3, igii xiv 



Stated Meeting, December i , igii xiv 



Corrigendum xv 



Index , xvii 



PHILADELPHIA 



THE AMERICAN PHILOSOPHICAL SOCIETY 

 104 South Fifth Street 



1911 



