CONTRIBUTIONS 



TO 



GEOLOGY. 



ISAAC LEA, 



MEMBER OF THE AMERICAN PHILOSOPHICAL SOCIETY ; 

 OF THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA ', 



OF THE LYCEUM OF NATURAL HISTORY OF NEW YORK J 

 HONORARY MEMBER OF THE MEDICAL SOCIETY OF ORANGE COUNTY, 



NEW YORK ; 

 MEMBER OF THE ROYAL PHYSICAL SOCIETY OF EDINBURGH ; 



OF THE BRITISH ASSOCIATION OF SCIENCE; 



OF THE NATURAL HISTORICAL SOCIETY OF MONTREAL ; 



CORRESPONDING MEMBER OF THE LINNjEAN SOCIETY OF BOURDEAUX, 



ETC. ETC. 



PHILADELPHIA : 



CAREY, LEA AND BLANCHARD. 

 1833. 



