POSTKARTE Besser, Leopold Author: Besser, Leopold Recipient: Haeckel, Ernst Corporation: Asyl Pützchen bei Bonn Dating: 24.07.1886
POSTKARTE Chumley, James Author: Chumley, James Recipient: Haeckel, Ernst Corporation: Challenger Expedition Office Dating: 23.12.1886
POSTKARTE Ortmann, Arnold E... Author: Ortmann, Arnold E... Recipient: Haeckel, Ernst Dating: 10.09.1886
POSTKARTE Liliencron, R... v. Author: Liliencron, R... v. Recipient: Haeckel, Ernst Dating: 22.05.1886