Raymond L. Ditmars: His Exciting Career With Reptiles, Insects and Animals by Laura Newbold Wood
People to check on:
Laurence Klauber (The Rattlesnakes), Clifford Pope (Snakes alive and how they live), H. B. "Bern" Bechtel (first bred amelanistic corns), Carl Kauffeld (Snakes and snake hunting), Ross Allen
Somewhere I read that the spotty distribution of aesculapian rat snakes in Europe could be correlated with temples to Aesculapius in the Roman Empire.