Since Sir John Evans read his paper on ‘Discoveries of Stone Implements in Lough Neagh’ before the Society in January 1867, the older flint industry of the Lower Bann valley has come to possess a full literature. Much of that literature includes some reference to the characteristic implements found from time to time within the beds of diatomaceous earth along the river's ancient flood-level, but the many papers on the subject fail curiously to discuss the clue afforded by these finds to the age of this widely known culture. It is true that in 1909 Mr. Wilfred Jackson, in the course of a report on the diatomite deposits, gave a more particular account of the prehistoric material disclosed in the diggings, but little of value has been contributed to the problem's solution from the geological standpoint.