The juvenile lead was successively played by James Ellison, Russell Hayden, George Reeves, Rand Brooks and Jimmy Rogers. George Hayes (later to become known as ``Gabby'' Hayes) originally played Cassidy's grizzled sidekick, Windy Halliday. After Hayes left the series because of a salary dispute with producer Harry Sherman, _he_was replaced by the comedian Britt Wood as Speedy McGinnis and finally by the veteran movie comedian Andy Clyde as California Carlson. <sep>, Pronoun: he