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Chaunograptus on a bryozoan-encrusted cephalopod (Upper Ordovician; Cincinnatian outcrop belt, USA) 2
James St. John a posté une photo : Chaunograptus sp. - problematic graptolites(?) from the Ordovician of the Cincinnatian outcrop belt, USA. Graptolites are an extinct group of he...