Well sir, I followed your links, downloaded the book, and looked through it to find the instance of this saying.

As you note, the book was caricatures of Hollywood actors of the day, with a humorous saying written below their name. It is 166 pages long with one actor/caricature/saying per page, one page forward, and 165 actors.

Under the caricature and name of one Jimmy Stewart, reads "You can take a boy out of the country, but you can't take the country out of a boy."

Thank you for posting this!! Better late than never.