Alphones Pyramus de Candolle (1806-1893), the son of Augustin-Pyrame de Candolle (1778-1841), has been an important figure (as was his father) in the development of plant geography.
The younger Candolle's work "Géographie botanique raisonnée" (1856) has been an especially important text for the history of plant geography since it combines botanical arithmetic with hypothesis driven scientific research. The scholar Janet Browne call this text "the cornerstone of mid-century ideas on the subject".[^1]
I was wondering if this text (or any of his for example his "Essai élémentaire de Géographie botanique" from 1820) has been translated in either German or English as these two languages were the other principal languages of biological distribution studies. It would also help myself, since my French is regrettably limited.
[^1]: Browne, J. 2001. History of Biogeography. eLS, p. 2
EDIT: As noted in my answer the Essai élémentaire de Géographie botanique was written by Auguste de Candolle.