A very soft shoe performance for old hoofers, or those who remember when being ""on the boards"" had nothing to do with the stock exchange. ""The World Famous Harrity Family"" consisted of Dad. ""the greatest novelty dancer who ever lived,"" little sister Marie who was on her toes before age three, Mom, who had a ""good set of pipes"" when she wasn't nervously squeaky and young Richard, song and dance and you name it. This is a whistle stop tour of their life on the small town vaudeville circuit where Dad came up with more ballyhoo stunts than Miz Mazepah had gimmicks. There was Queenie, the dancing bear, Professor White, ventriloquist with dummies and Madam White ""The Whistling Prima Donna."" And there was Mr. Greet, the versatile Scot. They were stranded in Nebraska; Dad, ""Ben Hur Harrity"" once won a chariot race; the family won a fight with four drunken midgets and they were probably the first to make the silent screen talk (by standing behind it). Somehow this world, with all its inherent interest, manages to seem a trifle dulled by time. Perhaps Mr. Harrity is reminiscing about a little too much, a little too late.