Posts by Harry Zirlin
My day at St. Clair, PA. September 20, 2014. St Clair is
My day at St. Clair, PA. September 20, 2014. St Clair is well-known fossil fern locality of the Pennsylvanian Period (300 milion years ago, give or ...
My day at St. Clair, PA. September 20, 2014. St Clair is well-known fossil fern locality of the Pennsylvanian Period (300 milion years ago, give or ...