Donated in 2009 by the late Dr William Arthur Watts, former President of the Royal Irish Academy, this collection comprises field notebooks of Danish botanist and quaternary geologist, Prof. Knud Jessen, Hon. MRIA. Professor Jessen came to Ireland at the invitation of the Committee for Quaternary Research in Ireland, chaired by Irish naturalist, Robert Lloyd Praeger, MRIA, to study the history of Irish bogs and their flora. The five field notebooks cover the period 1934-1949. Publication of this groundbreaking work on the history of the vegetation of the country was delayed by the war, but Jessen’s research was eventually published by the Academy as ‘Studies in late quaternary deposits and flora-history of Ireland’, Proceedings RIA 52 B (1948-1950), pp. 85-290.

The collection also includes a photograph of Jessen and a copy of his important paper with Anthony Farrington, MRIA, then Secretary of the Royal Irish Academy, ‘The Bogs at Ballybetagh, near Dublin, with remarks on late-glacial conditions in Ireland’, in Proceedings RIA 44 B (1937-1938), pp. 205-260.

Knud Jessen was State Geologist in Denmark from 1917-31. In 1931 he was appointed Professor of Botany at the University of Copenhagen. He was director of the Copenhagen Botanical Garden until 1955. Frank Mitchell’s obituary of Jessen was published in the Annual Report of the RIA, 1971-1972, pp. 5-6.