BRIEF OHNE UMSCHLAG Bacmeister, Adolf Author: Bacmeister, Adolf Recipient: Haeckel, Ernst Dating: 22.03.1871
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Corporation: Museum of Comparative Zoology, at Harvard College Dating: 21.02.1871
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Dating: 17.09.1871
BRIEF OHNE UMSCHLAG Darwin, Charles Author: Darwin, Charles Recipient: Haeckel, Ernst Dating: 03.03.1871
BRIEF OHNE UMSCHLAG Darwin, Charles Author: Darwin, Charles Recipient: Haeckel, Ernst Dating: 27.12.1871
BRIEF OHNE UMSCHLAG Stremayr, Karl Ritter von Author: Stremayr, Karl Ritter von Recipient: Haeckel, Ernst Dating: 29.01.1871
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 26.12.1871
