Fonds consists of 27 diaries of William Thornton Cust Boyd dated 1878 through 1917. Five of the diaries, 1884-1888, include financial records. The diaries recount the private and public life of Boyd, and include references to his wife, Meta, and their children, and social activities with family and friends including boating excursions and picnics. He refers throughout to Richard Birdsall Rogers (1857-1927), superintending engineer of the Peterborough Lift Lock, in social and business terms, and the two often conduct business relating to the Trent Valley Canal. Activities which Boyd participated in regularly include yachting and boating (on the "Calumet", "Ogemah", and "Ajax"), curling, hunting, gardening, tree planting, playing cards, skating, canoeing, and attending the theatre. He recounts details of the illnesses, deaths and funerals of acquaintances and family members, including his step-brother, Mossom (Mossie) Martin Boyd. Boyd recounts in detail the building of his house by John E. Belcher ([184-]-1915), architect, civil engineer, and surveyor. This house is now operated as Case Manor Nursing Home. The diaries speak of local and federal politics, World War I, and the activities of the church. They also detail the activities of the Lindsay, Bobcaygeon and Pontypool Railway Company, the Trent Valley Navigation Steamship Company, and the day-to-day operation of the family lumbering and cattle/buffalo enterprises.

This addition to the fonds consists of bird spotting forms for the Ontario Breeding Bird Atlas and Ontario Breeding Bird Atlas error forms. Also included in the fonds are numerous publications and newsletters from various naturalist clubs across Ontario.