| original |
Early Gothlandian |
|
New York |
Miller,M.A. et al. Palynomorphs from the Silurian Medina Group, (Lower Llandovery), of the Niagara Gorge, Lewiston, New York, USA. |
1982 |
| details |
Ashgillian |
Rhuddanian |
New York |
Richardson,J.B. et al. Sporomorphs and plant megafossils. (In: A Global Standard for the Silurian System. C.H. Holland and M.G.Bassett, editors) |
1989 |
| details |
Early Gothlandian |
|
New York |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Early Gothlandian |
|
New York |
Strother,P.K. A classification Schema for the Cryptospores |
1991 |