FAILURE OF THE CESSNA 150 PILOT TO SEE-AND-AVOID THE CESSNA 152 (INADEQUATE VISUAL LOOKOUT), AND FAILURE OF THE TOWER CONTROLLER TO PROVIDE ADEQUATE SERVICE. FACTORS RELATED TO THE ACCIDENT WERE: HIGH TRAFFIC DENSITY, WHICH RESULTED IN FREQUENCY CONGESTION, AND FAILURE OF THE CESSNA 150 PILOT TO FOLLOW ESTABLISHED TRAFFIC PATTERN PROCEDURES.