L'abbé Bacheley et la découverte des premiers dinosaures et crocodiliens marins dans le Jurassique des Vaches Noires (Callovien/Oxfordien, Normandie)

Georges Cuvier published in 1808 the first scientific descriptions of dinosaur and marine crocodilian (Thalattosuchia) remains from the collection of a certain “Abbé Bachelet [sic]”, a naturalist in Rouen (Normandy, France). According to Cuvier, “Bachelet” never published any papers about the circumstances of the discovery of these fossils. Since then, there has been some doubt about their precise geographic and stratigraphic origin. This article reveals for the first time the identity of Charles Bacheley (1716-1795) and presents the biography of this pioneer in Norman palaeontology. He is the author of a note published in 1778 on the petrifactions found on the coast of Pays d'Auge (Calvados) between the Vaches Noires and Trouville-sur-Mer. This study has gone completely unnoticed and reveals that the specimens from the Bacheley collection studied by Cuvier come from the “Marnes de Dives” (Upper Callovian) or the “Marnes de Villers” (Lower Oxfordian) of the Vaches Noires cliffs. Bacheley identified these dinosaurs and marine crocodilian remains as belonging to “fishes,” which at that time also included cetaceans according to popular usage. Interestingly, Bacheley did not exclude the possibility that these petrified bones could belong to animals distinct from living forms.