| RefNo | Title | Source |
| DF/ZOO/200/19/146 | Hooker, W [S] | |
| WP/1/3/55 | Letter from Richard Spruce to Alfred Russel Wallace | |
| WP/12/17 | 'A sketch of the life and labours of Sir William Jackson Hooker With portrait', by J D Hooker | |
| WP/1/3/26 | Letter from Richard Spruce to Alfred Russel Wallace | |
| WP/1/3/33 | Letter from Alfred Russel Wallace to George Silk | |
| WP/2/3/38 | Obituaries and Memoirs of Alfred Russel Wallace | |
| WP/8/3/5 | Certificate from the Royal Botanic Gardens Kew 16 Nov 1908 acknowledging receipt from Alfred Russel Wallace of volumes and letters | |