BRIEF [O.A.] Barboye du Bocage, José Vicente Author: Barboye du Bocage, José Vicente Recipient: Haeckel, Ernst Dating: 26.12.1870
BRIEF OHNE UMSCHLAG Darwin, Charles Author: Darwin, Charles Recipient: Haeckel, Ernst Dating: 23.06.1870
BRIEF [O.A.] Alglave, Emile Author: Alglave, Emile Recipient: Haeckel, Ernst Corporation: Revue des Cours Littéraires et Scientifiques Dating: 14.03.1870
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Dating: 10.07.1870
BRIEF OHNE UMSCHLAG Müller, Hermann Author: Müller, Hermann Recipient: Haeckel, Ernst Dating: 17.02.1870