| details |
Paleozoic |
|
Nd |
Taylor,T.N. Pollen and pollen organ evolution in early seed plants. |
1981 |
| details |
Middle Pennsylvanian |
Late Pennsylvanian |
Illinois |
Rothwell,G.W. Pollen grains of the Pennsylvanian Callisto Phytaceae (Pteridospermopsida) |
1972 |
| original |
Middle Pennsylvanian |
|
Illinois |
Millay,M.A. et al. Idanothekion, gen.nov., a synangiate pollen organ with saccate pollen from the Middle Pennsylvanian of Illinois. |
1970 |
| details |
Middle Pennsylvanian |
|
Illinois |
Millay,M.A. et al. Studies of living and fossil saccate pollen grains |
1970 |
| details |
Middle Pennsylvanian |
|
Illinois |
Millay,M.A. et al. Microgametophyte development in the Paleozoic seed fern Family Callistophytaceae. |
1974 |
| details |
Carboniferous |
|
USA |
Balme,B.E. Fossil in situ, spores and pollen grains: An annotated catalogue. |
1995 |