BRIEF [O.A.] Walther, Johannes Author: Walther, Johannes Recipient: Haeckel, Ernst Dating: 30.07.1883
BRIEF [O.A.] Nägeli, Carl Wilhelm Author: Nägeli, Carl Wilhelm Recipient: Haeckel, Ernst Corporation: Königlicher Botanischer Garten Dating: 07.11.1883
BRIEF [O.A.] Zittel, Karl Alfred von Author: Zittel, Karl Alfred von Recipient: Haeckel, Ernst Dating: 28.07.1883
BRIEF [O.A.] Siebold, Carl Theodor Ernst von Author: Siebold, Carl Theodor Ernst von Recipient: Haeckel, Ernst Dating: 18.02.1883
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Stuxberg, Anton Dating: 03.08.1883