| details |
Middle Pennsylvanian |
|
Illinois |
Taylor,T.N. Paleozoic seed studies. |
1965 |
| details |
Nd |
|
Nd |
Potonie,R. Synopsis of the Sporae in situ. |
1962 |
| details |
Stephanian |
|
France |
Florin,R. On the morphology of the pollen grains in some Palaeozoic Pteridosperms. |
1937 |
| details |
Middle Pennsylvanian |
|
Illinois |
Darrah,E.L. The microstructure of some Pennsylvanian seeds and megaspores studied by maceration. |
1968 |
| details |
Middle Pennsylvanian |
|
Iowa |
Darrah,E.L. The microstructure of some Pennsylvanian seeds and megaspores studied by maceration. |
1968 |
| details |
Middle Pennsylvanian |
|
Kansas |
Darrah,E.L. The microstructure of some Pennsylvanian seeds and megaspores studied by maceration. |
1968 |