Wife called me on the walkie-talkie, one day, a bit frantic. She was walking the dog through the woods. "Tim, quick, what's that rhyme? Brown on red, ... black on yellow, ... how does it go??"
She saw a snake with colored bands. The rhyme she wanted was "Red on black, friend of Jack. Red on yellow, kill a fellow". Turns out, it was a friend. We think.