Max Baer Sr., heavyweight champ of the world for just under a year in the ‘30s, was born February 11, 1909. Best known as the dad of Max Baer Jr. (Jethro on “The Beverly Hillbillies”), this legendary puncher somewhat neglected his boxing career in favor of acting, though most of his film work consisted of small parts. Here, the most colorful boxer of all time (until Ali came along) dances in a delirious (and eternal — this is a short part of it) routine from the pre-Code film “The Prizefighter a