In pursuing the evidence of human antiquity furnished by implements, a start may be made from the data corresponding to the Galley Hill skeleton in column 5 of Table A. Two divergent views are expressed here, since the alternatives "Acheulean" or "Strépyan" are offered in the table. In the former instance (Acheulean) a recent writer (Mr Hinton, 1910) insists on the Pliocene affinities of the high-level terrace mammals. But as a paradox, he states that the high-level terrace deposits provide implements of the Acheulean type, whereas the Chellean type would be expected, since on the Continent implements associated with a fauna of Pliocene aspect, are of Chellean type. To follow Mr Hinton in his able discussion of this paradox is tempting, but not permissible here; it must suffice to state that the difficulty is reduced if Professor Rutot's[31] view be accepted. For the Strépyan form of implement (which M. Rutot recognises in this horizon) is older than the others mentioned and resembles the Chellean type. To appreciate this, the sequence which Professor Rutot claims to have established is here appended. A. _Pleistocene Period._ (All Palaeolithic types except No. 1.) 1. Azilian } } 2. Magdalenian } } 3. Solutréan } Types found in caves as well as in alluvial deposits. } 4. Aurignacian } } 5. Mousterian } 6. Acheulean. Fauna of S.-E. Britain has a Pliocene aspect. High-level terrace of Thames valley (Hinton, 1910). 7. Chellean. Fauna of Continent has Pliocene affinities (Hinton, 1910). 8. Strépyan. Galley Hill Skeleton. High-level terrace, Thames basin (Rutot, 1911). 9. Mesvinian. Implements on surface of chalk-plateau, Ightham, Kent (Rutot, 1900). 10. Mafflian. Galley Hill skeleton (Rutot, 1903). Mauer jaw (Rutot, 1911). 11. Reutelian. High-level terrace of Thames basin, Rutot, 1900. The Reutelian implement is "eolithic," and is found unchanged in stages assigned to the Pliocene, Miocene and Oligocene periods (Rutot, 1911). The duration of the Pleistocene period is estimated at about 139,000 years (Rutot, 1904). B. _Pliocene Period._ 12. Kentian (Reutelian). C. _Miocene Period._ 13. Cantalian (Reutelian). D. _Oligocene Period._ 14. Fagnian (Reutelian). E. _Eocene Period._ 15. [Eoliths of Duan and other French sites: not definitely recognised in 1911 by Rutot.] Several results of vast importance would follow, should the tabulated suggestions be accepted unreservedly in their entirety.