Sends a notice on a reptile intermediate between true Triassic reptiles and Devonian fishes ["Sur le reptile (Actinodon)", C. R. Hebd. Acad. Sci. 63 (1866): 341–4].

Expresses his admiration for CD, and his growing sense that transformation of species is probable, though he does not share CD’s explanation of the cause. He avoids the question, since he lacks requisite knowledge and is convinced that there are causes of which God alone knows the secret.