Alethopteris serli (Brongniart) with Cordaites sp.
Black shale. On one surface are two white seed fern fronds. The other surface shoes a leaf from a giant horsetail.
Carboniferous, Pennsylvanian, Coal Shales, Pottsville Formation.
St. Clair, Schuylkill County, Pennsylvania, USA.
Specimen : 10.5 x 8.5 cm.
