Subject
Paleontology
Geology
23
Geology, Stratigraphic
13
Ammonoidea
6
Footprints, Fossil
5
Bivalves, Fossil
2
Conservation of natural resources
2
Crinoidea, Fossil
2
Erosion
2
Extinct mammals
2
Fusulinidae
2
Gastropoda, Fossil
2
Geology, Economic
2
Mines and mineral resources
2
National monuments Management
2
Natural monuments Management
2
Petrology
2
Prehistoric Trackways National Monument (N.M.)
2
Public lands Management
2
Tularosa Valley (N.M. and Tex.) History
2
Vertebrates, Fossil
2
White Sands National Park (N.M.) History
2
Animals, Fossil
1
Brachiopoda, Fossil
1
Briquets (Fuel)
1
Building materials
1
California
1
Clay
1
Coal
1
Colloids
1
Corals, Fossil
1
Dakota Aquifer
1
Delaware Altitudes
1
Eostaffella
1
Fishes, Fossil
1
Fruitland Formation (Colo. and N.M.)
1
Fuel Testing
1
Glacial epoch
1
Granite
1
Historical geology
1
Luna County (N.M.)
1
Maine Altitudes
1
Maryland Altitudes
1
Millerella
1
Mine explosions
1
Mollusks, Fossil
1
Nevada
1
New Hampshire Altitudes
1
New Mexico
1
New Mexico Description and travel
1
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