Schimper (Traité de Paléontologie végétale, t. iii, p. 680) established in 1874 his Étage paléocène pour les “Sables de Bracheux, Travertins anciens, Lignites et grés du Soissonnais”, which are coeval with the Thanet Sands and the Woolwich Series. As there is a natural break between these and the London Clay (=the French Sables de Cuise), and as the Eocene contained more varied faunas than the Oligocene, Miocene, and Pliocene Tertiaries, I accepted that division in my description of the Kopenhague fauna, which formed the Lower Palæocene, together with the Montien of Belgium, older marine beds which are unknown in England.