His Petrifacta Derbiensia recounts that White Watson 's uncle and workers at the Black Marble quarry called some of the fossils `` crocodile tails '' as they thought they were the remains of crocodiles .
His Petrifacta Derbiensia says that White Watson 's uncle and workers at the Black Marble mine called some of the fossils `` crocodile tails '' , because they thought they were the remains of crocodiles .