18 CLASSIFIED KEY TO THE INDEX. 
Page. 
Minnesota 103 
Missouri 103 
Montana 103 
Nebraska 103 
Nevada 103 
Newfoundland 104 
New Hampshire 104 
New Jersey 104 
New Mexico - 104 
New York 104 
North Carolina 104 
North Dakota 104 
Ohio 104 
Oklahoma 105 
Oregon 105 
Paleontology 105 
Cambrian _ 105 
Silurian 105 
Devonian 105 
Carboniferous 105 
Jura-Trias 105 
Cretaceous 106 
Tertiary miscellaneous 106 
Eocene 106 
Miocene 106 
Pliocene 106 
Pleistocene 106 
Miscellaneous 107 
Genera and species described 107 
Pennsylvania 125 
Petrology 125 
Arkansas 125 
California 125 
Canada 125 
Colorado 125 
District of Columbia 125 
Idaho 125 
Maine 125 
Maryland 125 
Massachusetts 125 
Michigan 125 
Minnesota 126 
Missouri 126 
Montana 126 
New York 126 
Pennsylvania 126 
Rhode Island 126 
Texas 126 
Vermont 126 
Wisconsin * 126 
Wyoming 126 
Miscellaneous discussions 126 
Rocks described 126 
Physiographic geology 127 
