| original |
Early Pennsylvanian |
|
Michigan |
Arnold,C.A. A Heterosporous species of Bowmanites from the Michigan Coal Basin |
1944 |
| details |
Recent |
|
Nd |
Potonie,R. Position of the Paleozoic spore genera in the natural system. |
1954 |
| details |
Paleozoic |
|
Nd |
Potonie,R. The spores of Palaeozoic plants in the natural (Morphologic) system |
1954 |
| details |
Pottsville |
|
Michigan |
Potonie,R. Synopsis of the Sporae in situ. |
1962 |
| details |
Carboniferous |
|
Nd |
Bharadwaj,D.C. et al. Suggestions for a morphological classification of sporae dispersae. |
1968 |
| details |
Nd |
|
Nd |
Balme,B.E. Fossil in situ, spores and pollen grains: An annotated catalogue. |
1995 |