BRIEF OHNE UMSCHLAG Thomson, Arthur John Author: Thomson, Arthur John Recipient: Haeckel, Ernst Dating: 10.07.1890
BRIEF OHNE UMSCHLAG Thomson, Arthur John Author: Thomson, Arthur John Recipient: Haeckel, Ernst Dating: 21.07.1890
POSTKARTE Chumley, James Author: Chumley, James Recipient: Haeckel, Ernst Corporation: Challenger Expedition Office Dating: 21.06.1890
BRIEF OHNE UMSCHLAG Murray, John Author: Murray, John Recipient: Haeckel, Ernst Corporation: Challenger Expedition Office Dating: 17.07.1890