BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 26.12.1871
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Wundt, Wilhelm Dating: 23.05.1871
BRIEF OHNE UMSCHLAG Greeff, Richard Author: Greeff, Richard Recipient: Haeckel, Ernst Dating: 16.01.1871
BRIEF OHNE UMSCHLAG Grönland, Theude Author: Grönland, Theude Recipient: Haeckel, Ernst Dating: 17.11.1871
BRIEF OHNE UMSCHLAG Focke, Wilhelm Olbers Author: Focke, Wilhelm Olbers Recipient: Haeckel, Ernst Dating: 09.05.1871
BRIEF OHNE UMSCHLAG Bacmeister, Adolf Author: Bacmeister, Adolf Recipient: Haeckel, Ernst Dating: 22.03.1871