Robuta

https://www.krantz-online.de/en/melonechinus-multiporus-6-spec.-cast/C102 Melonechinus multiporus, 6 spec. (Cast) | C102 | Krantz since 1833 Melonechinus multiporus (OWEN)Six specimens of the sea urchin on a slab.Age: Lower Carboniferous, Mississippian;Locality: St. Louis, Missouri, USASize: approx.... melonechinusspeccastkrantzsince