Note 16 — Chapter I · The Stone Age: its Duration and its Place in Time.

Lubbock: “On the Evidence of the Antiquity of Man Afforded by the Physical Structure of the Somme Valley” (Nat. Hist. Review, vol. ii.). Prestwich: “On the Occurrence of Flint Implements Associated with the Remains of Extinct Species in Beds of a Late Geological Period” (Phil. Trans., 1860). Evans: “Flint Implements in the Drift” (Arch., 1860–62).