This work includes descriptions and illustrations of many North American reptiles.
Another important work attributed to him is The Lost Chapter of the Acts of the Apostles, also dubbed the Sonnini manuscript, which was allegedly found in his publication Voyage en Grèce et en Turquie and later published and translated to English some time not earlier than 1801.
The work, which first appeared in London in 1871, has received mixed opinions from different Christians, with most scholars rejecting it as a modern pseudepigraph.