"
Petrified fossil remains" were known from the Sables du Castrais Formation since at least the 18th century, and several of these fossils were described by
Cuvier (1804) and Cuvier (1822) as belonging to
Palaeotherium and
Lophiodon. In 1845, a jaw assigned to
Lophiodon lautricensis was discovered in the formation and was described by
Noulet (1851); Noulet also mentioned that he had himself collected fossils from the formation alongside
pharmacist J. Parayre as early as .
Léonce Roux du Carla discovered several more fossils from the Grès d'Issel Member of the Sables du Castrais formation from February 1855 until his death in 1859, and this helped Noulet (1858) to confirm the
Eocene age of the deposit. The Grès d'Issel Member was identified by Henri de Sévérac in 1873, and the Sables du Castrais Formation was first described by M. Richard in 1946. The Grès d'Issel Member is located in a quarry which closed around 1966 and is now inaccessible due to it currently being located underneath a private garden. == Age of the formation ==