Original handwritten letter, signed.

Paris, [not dated - after 1861]. Single leaf (20.2 x 13.3 cm). = Letter written by the Swiss-American ichthyologist and marine biologist Alexander Emmanuel Rodolphe Agassiz (1835-1910), to an unknown colleague, perhaps the French zoologist Alphonse Milne-Edwards (1835-1900). Alexander Agassiz commented upon the rare work edited by Louis Maillard (1814-1865) on the island Réunion in the Indian Ocean: "Je réussi seulement à trouver le texte et les planches des mollusques et comme il y a d'autres figures qui nous seraient importantes, je vous serais fort obligé si vous pouviez par hasard me donner quelques renseignements à ce sujet […] " ("I only succeeded in finding the text and the plates of the molluscs and as there are other figures which would be important to us, I would be very much obliged to you if you could by chance give me some information on this subject"). Apparently, Agassiz only had Gérard Paul Deshayes's (1861) part on the molluscs, and, in all probability, not the part on the crustaceans, Faune carcinologie (1862), written by Alphone Milne Edwards. Left edge a bit irregular, otherwise fine.