Thayer Expedition Papers

Expedition Background

In April 1865, Museum of Comparative Zoology founder and director Louis Agassiz set off for Brazil with his wife Elizabeth and a dozen assistants on a fifteen-month collecting expedition financed by Boston banker Nathaniel Thayer. Agassiz’s primary goal was to investigate the distribution of Brazil’s freshwater fish species.

The Ernst Mayr Library’s Thayer Expedition Papers include field notes, specimen lists, correspondence, diaries, sketches, and other materials, digital images which can be accessed by clicking on the thumbnails below.

Thayer Expedition Papers

Among the assistants on the journey was Louis Agassiz’s personal and principal artist Jacques Burkhardt, whose fish watercolors and landscape paintings, a highlight of the expedition’s treasures, are in the Jacques Burkhardt Collection.

See also: A Journey in Brazil by Louis and Elizabeth Agassiz (Boston: Ticknor and Fields, 1868).

Agassiz letter to Mayor 9, December 1985 Agassiz, Alexander. 1 letter to Auguste Mayor, 9 December 1865, photostatic reproduction (bAg 10.10.34a).
Lists of Specimens Agassiz, A., and Agassiz, Louis. Lists of specimens (bAg 826.50.1).
Agassiz letters to Nathaniel Thayer Agassiz, Elizabeth Cary. 2 letters to Nathaniel Thayer (bAg 13.10.6).
Agassiz letter to Tom Ward, 6 June 1865 Agassiz, Louis. 1 letter to Tom Ward, 6 June 1865 (bAg 15.10.54).
Lists of specimens with correspondence Agassiz, L. Lists of specimens with correspondence, primarily to A. Agassiz (bAg 826.50.2).
Notes on Brazilian fishes 15.41.6 Agassiz, L. Notes on Brazilian fishes(bAg 15.41.6).
Notes on Brazilian fishes 15.42.4 Agassiz, L. Notes on Brazilian fishes(bAg 15.42.4).
Catalogue systematique de tous les poissons de a'Amazone Agassiz, L. Catalogue systematique de tous les poissons de l’Amazone(bAg 15.41.7).
Letter to William Gray, 29 July 1865 Bellows, F.W.G. 1 letter to William Gray, 29 July 1865, writing for Pacific Mail Steamship Company, New York, concerning Thayer Expedition (bAg 826.30.1).
Letter to Agassiz, 20 April 1866 Cary, Thomas Greaves. 1 letter to A. Agassiz, 20 April 1866, Maldonado, Uruguay (bAg 188.10.1).
Catalogue of contents of can no. 4, Cannavieiras Collection Hartt, Charles, and Copeland, Edward.Catalogue of contents of can no. 4, Cannavieiras Collection (bAg 437.50.1).
1 letter to Samuel Henshaw, 19 September 1918, concerning Thayer Expedition photograph Hunnewell, Walter. 1 letter to Samuel Henshaw, 19 September 1918, concerning Thayer Expedition photograph (bMu 1498.10.1).
James, William. Brazil diary, 1865 James, William. Brazil diary, 1865(bMu 1556.41.1).
St. John, Orestes. Lists of fishes, 1865 St. John, Orestes. Lists of fishes, 1865 (bMu 2411.50.1)
St. John, O. List of fishes, 1866 St. John, O. List of fishes, 1866 (bMu 2411.50.2).
St. John, O. List of fishes, for Louis Agassiz St. John, O. List of fishes, for Louis Agassiz (bMu 2411.50.3).
Thayer, Nathaniel. 1 letter to William Gray, 26 July 1865, resigning as MCZ treasurer Thayer, Nathaniel. 1 letter to William Gray, 26 July 1865, resigning as MCZ treasurer (bMu 2761.10.1).
1 letter to George Ticknor, 25 April 1866 Ware, H. 1 letter to George Ticknor, 25 April 1866, writing for John Albion Andrews, concerning Thayer Expedition, accompanied by enclosed letter from Jose Antonio Saraiva, writing for Pedro II, Emperor of Brazil, to John Albion Andrews, 15 December 1865, plus English translation of Portuguese original (bAg 826.30.2).
Thayer Expedition group photograph A Thayer Expedition group photograph featuring Jacques Burkhardt, Joao Coutinho, D. Bourget, Newton Dexter, Walter Hunnewell, William James and Stephen van Rensselaer Thayer (Portrait Collection) is in HUL’s Visual Information Access catalog (VIA).
Z: Brazilian diary and sketch book, 1865 Also, an item owned by Houghton Library (included in the MCZ’s Thayer Expedition LDI Project), "James, William, 1842-1910. Papers. [Notebook 4] Z: Brazilian diary and sketch book, 1865 (MS Am 1092.9 (4498). Houghton Library)".