Cowboys running back Felix Jones is listed as questionable for Saturday's game against Philadelphia after missing practice all week because of hamstring tightness.Linebacker DeMarcus Ware (neck stinger) and nose tackle Jay Ratliff (ribs) are also listed as questionable, though both are expected to play after having limited participation at practice three days in a row.The NFC East-leading Cowboys had said during the week that they were being cautious with Jones, who is coming off consecutive 100-yard rushing games after the season-ending ankle injury to rookie DeMarco Murray.Sammy Morris, a 12-year NFL veteran who was signed with Dallas and made his season debut last week, would start if Jones doesn't play.Dallas also Friday signed running back Chauncey Washington to the active roster from its practice squad.