Out of character, Bud forgets to place the blue flyer back in his case and that's what keeps him from hopping the train. The stones and their strange code seem obvious to the reader as places where Bud's mother may have been with his father. The police burn down Hooverville, which forces Bud to head back to Flint.
Hope this helps TPWK
Anecdote would be the correct answer
