At 0917 mountain time, a Cessna 172S veered off runway 01 during landing and struck a taxiing Cessna 172N at Glendale Municipal Airport. None of the four occupants of the two airplanes was injured. The pilot of the landing airplane said he completed air work in the local practice area and returned for landing. Upon landing, the airplane bounced, veered to the left, and exited the runway about midfield between a taxiway and the high-speed taxiway. It crossed a gravel area between the runway and a parallel taxiway and struck the oncoming airplane. Each airplanes left wing tip contacted the left wing root of the opposing airplane.