To Ernst Haeckel   30 December [1863] – 3 January [1864]

Letter and/or further information available at https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-4361.xml.

Also published in The Correspondence of Charles Darwin, vol. 11.

Please cite as “DCP-LETT-4361,” in Ɛpsilon: The Charles Darwin Collection accessed on 29 April 2024, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-4361