Hard-backed notebook inscribed 'Record 1923'. Includes transcript entries from diaries, 12 Oct 1923-12 Feb 1926, covering Darlington's first years at the John Innes Institution up to the death of Bateson. Several of the entries have annotations added at a later date.

At the rear of the book are quotations and recollections of J.B.S. Haldane, various dates, 1926-1938, and (on a loose page) a caricature of A.D. Hall, 1927.

Miscellaneous research notes occur on several pages. The notebook is similar to those used for early research at the John Innes Institution.