BRIEF [O.A.] Lo Bianco, Salvatore Author: Lo Bianco, Salvatore Recipient: Haeckel, Ernst Dating: 01.01.1891
BRIEF [O.A.] Böhtlingk, Arthur Author: Böhtlingk, Arthur Recipient: Haeckel, Ernst Dating: 17.09.1891
BRIEF [O.A.] Böhtlingk, Arthur Author: Böhtlingk, Arthur Recipient: Haeckel, Ernst Dating: 07.10.1891
BRIEF [O.A.] Béraneck, Edmont Author: Béraneck, Edmont Recipient: Haeckel, Ernst Corporation: Académie de Neuchâtel Dating: 08.01.1891
BRIEF [O.A.] Bellesme, Jousset de Author: Bellesme, Jousset de Recipient: Haeckel, Ernst Corporation: Direction de l'Aquarium du Trocadéro Dating: 01.08.1891
BRIEF [O.A.] Aschieri, Ettor Luigi Author: Aschieri, Ettor Luigi Recipient: Haeckel, Ernst Dating: 16.09.1891
BRIEF [O.A.] Aschieri, Ettor Luigi Author: Aschieri, Ettor Luigi Recipient: Haeckel, Ernst Dating: 17.12.1891
BRIEF [O.A.] Van Bambeke, Charles Author: Van Bambeke, Charles Recipient: Haeckel, Ernst Dating: 15.11.1891
BRIEF MIT UMSCHLAG Bedriaga, Jacques von Author: Bedriaga, Jacques von Recipient: Haeckel, Ernst Dating: 09.10.1891