Leaflets of Sagenopteris phillipsii: the dark leaflet in the middle and the one left below.
Other leaflets with this kind of venation are also of this species.
Furthermore Coniopteris sp. (right below) and the fern Eboracia lobifolia (horizontal pinna).
Ironstone from Cayton Bay. Width of the photo 9 cm.
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Click here for a restoration of the parts of this plant.
Aberrant leaf