AT a meeting of the Geological Society of London, held on May 5, Mr. S. Hazzledine Warren read a paper entitled “A Natural Eolith Factory beneath the Thanet Sand.” The discovery of flints fractured by natural pressure at the base of the Eocene is not, however, a novel experience, as, in 1910, M. l'Abbe H. Breuil described (“Sur la presence d'Eolithes a la base de I'Eocene Parisien,” L'Anthropologie, t. xxi., 1910, pp. 385–408) in great detail, and by means of no fewer than seventy-six excellent illustrations, a series of flaked specimens of the same kind as those now put forward by Mr. Warren. Also, in 1914, I published an account of the flaked flints occurring in the Lower Eocene “Bull-head” bed at Bramford, near Ipswich (Proc. P.S.E.A., vol. i., part 4, pp. 397–404), and gave a full account of this peculiar deposit and the nature of the fractures exhibited by some of the contained flints. It will thus be seen that this question has been fully discussed and threshed out for many years past.