1. Darwin and Henslow: The Growth of an Idea,1967
2. To Be an Invalid: The Illness of Charles Darwin;Colp,1977
3. The Autobiography of Charles Darwin, 1809–1882 (original omissions restored),1958
4. The Voyage of the Beagle;Darwin,1906
5. The Quest for the Father: A Study of the Darwin-Butler Controversy, as a Contribution to the Understanding of the Creative Individual;Greenacre,1963