| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Middle Pennsylvanian |
Late Pennsylvanian |
Illinois |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Kansas |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Desmoinesian |
|
Iowa |
Mamay,S.H. Some American Carboniferous fern fructifications. |
1950 |
| details |
Rhaetian |
|
Sweden |
Lundblad,B. Studies in the Rhaeto-Liassic floras of Sweden. I.Pteridophyta, Pteridospermae, and Cycadophyta from the Mining District of northwest Scania. |
1950 |
| details |
Rhaetian |
|
Sweden |
Lundblad,B. Studies in the Rhaeto-Liassic floras of Sweden. I.Pteridophyta, Pteridospermae, and Cycadophyta from the Mining District of northwest Scania. |
1950 |
| details |
Rhaetian |
|
Sweden |
Lundblad,B. Studies in the Rhaeto-Liassic floras of Sweden. I.Pteridophyta, Pteridospermae, and Cycadophyta from the Mining District of northwest Scania. |
1950 |
| details |
Quaternary |
|
Sweden |
Fries,M. et al. Pre-Quaternary pollen grains and spores found in Late-Glacial and post-Glacial Clays in Bohuslan, southwest Sweden. |
1950 |
| details |
Quaternary |
|
Sweden |
Fries,M. et al. Pre-Quaternary pollen grains and spores found in Late-Glacial and post-Glacial Clays in Bohuslan, southwest Sweden. |
1950 |
| details |
Quaternary |
|
Sweden |
Fries,M. et al. Pre-Quaternary pollen grains and spores found in Late-Glacial and post-Glacial Clays in Bohuslan, southwest Sweden. |
1950 |
| details |
Quaternary |
|
Sweden |
Fries,M. et al. Pre-Quaternary pollen grains and spores found in Late-Glacial and post-Glacial Clays in Bohuslan, southwest Sweden. |
1950 |
| details |
Quaternary |
|
Sweden |
Fries,M. et al. Pre-Quaternary pollen grains and spores found in Late-Glacial and post-Glacial Clays in Bohuslan, southwest Sweden. |
1950 |