Pharyngolepis oblongus, primitive jawless fish Spinosaurus This is poured in solid

This is poured in solid resin so it is very stable

a Messel frog

and hollow bones

about the time that dinosaurs began to appear

Pharyngolepis oblongus, primitive jawless fish Spinosaurus This is poured in solidPharyngolepis is an extinct genus of primitive jawless fish that lived in the Silurian period of what is now Norway. Pharyngolepis had well developed anal and caudal fins, but no paired or dorsal fins that would have helped stabilise it in the water, and so was probably a poor swimmer, remaining close to the sea bottom. The pectoral fins were instead replaced by bony spines, possibly for protection against predators, and there was a row of spines