POSTKARTE Chumley, James Author: Chumley, James Recipient: Haeckel, Ernst Corporation: Challenger Expedition Office Dating: 23.12.1886
POSTKARTE Besser, Leopold Author: Besser, Leopold Recipient: Haeckel, Ernst Corporation: Asyl Pützchen bei Bonn Dating: 24.07.1886
POSTKARTE Recipient: Haeckel, Ernst Corporation: Administration der neuen Zürcher Zeitung Dating: 09.09.1886
POSTKARTE Weinland, David Friedrich Author: Weinland, David Friedrich Recipient: Haeckel, Ernst Dating: 15.05.1886