BRIEF OHNE UMSCHLAG Schrader, Otto Author: Schrader, Otto Recipient: Haeckel, Ernst Dating: 10.01.1883
BRIEF [O.A.] Wielowiejski, Heinrich v. Author: Wielowiejski, Heinrich v. Recipient: Haeckel, Ernst Dating: 18.04.1883
BRIEF OHNE UMSCHLAG Weismann, August Author: Weismann, August Recipient: Haeckel, Ernst Dating: 21.08.1883
BRIEF [O.A.] Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 26.09.1883
BRIEF [O.A.] Hofmann-Stirl, Helene Author: Hofmann-Stirl, Helene Recipient: Haeckel, Ernst Dating: 15.17.1883
BRIEF OHNE UMSCHLAG Rodenberg, Julius Author: Rodenberg, Julius Recipient: Haeckel, Ernst Corporation: Deutsche Rundschau Dating: 15.07.1883
BRIEF [O.A.] Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 15.01.1883