On 10 October 1833, at Santa Fe, Argentina, he was "filled with astonishment" when he found a horse's tooth in the same stratum as fossil giant armadillos, and wondered if it might have been washed down from a later layer, but concluded this was "not very probable".
Den 10. oktober 1833 i byen Santa Fe i Argentina blev han "fyldt med forundring", da han fandt en hestetand i samme lag som fossilerne af gigantiske bæltedyr, og spekulerede på om den måske var blevet vasket ned fra et senere lag, men konkluderede at dette var "meget lidt sandsynligt".