Twenty-one species of teleost otoliths from the Sables de Grimmertingen are described. Six of them are new : Raniceps altus, « genus aff. Brosmopbycis » brevis, Otophidium caudatum, « genus Ophidiidarum » ornatissimus, Monomitopus grimmertingensis, « genus aff. Neobythites » spina. Although three species common to the Belgian Eocene are still present, the appearance of four typically Oligocène species together with numerous new species unknown in the Eocene suggest that these sands are of lower Oligocene age. They suggest a neritic fauna which lived in calm, somewhat deep water on a soft, muddy bottom. The abundance of gadids suggests a colder climate than that of the Eocene epoch
