This collection contains microfilm copies of 21 diaries kept by Asa Fitch, scientist and entomologist. The diaries reflect in considerable detail Fitch's life and thoughts from early adolescence through his education at the Rensselaer School (Class of 1827) and the Vermont Academy of Medicine in Castleton, his career as a scientist and state entomologist in New York, and his retirement. Also included are papers and genealogical materials relating to other members of the Fitch family.

The original diaries are owned by Yale University Manuscripts and Archives.