To Oswald Heer   4 August [1872–4]

Letter and/or further information available at https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-8454.xml.

Also published in The Correspondence of Charles Darwin, vol. 20.

Please cite as “DCP-LETT-8454,” in Ɛpsilon: The Charles Darwin Collection accessed on 28 April 2024, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-8454