BRIEF [O.A.] Arms, J... M... Author: Arms, J... M... Recipient: Haeckel, Ernst Corporation: Boston Society of Natural History Dating: 14.10.1893
BRIEF [O.A.] Bates, Geo... A... Author: Bates, Geo... A... Recipient: Haeckel, Ernst Dating: 13.06.1881
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Corporation: Museum of Comparative Zoölogy Dating: 12.09.1865
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Corporation: Museum of Comparative Zoölogy Dating: 20.11.1865
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Corporation: Museum of Comparative Zoology, at Harvard College Dating: 29.12.1868
BRIEF [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Corporation: Museum of Comparative Zoology, at Harvard College Dating: 28.04.1869
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 [O.A.] Agassiz, Alexander Author: Agassiz, Alexander Recipient: Haeckel, Ernst Corporation: Museum of Comparative Zoology, at Harvard College Dating: 10.03.1873