JP 8/3/71 4382-76 SUBJECT: MARLYN MASON PROGRAM: "LONGSTREET" ON AIR: PREMIERES THURSDAY, SEPT. 16 (9:00-10:00 p.m., EDT) P R E M I E R E Marlyn Mason is featured in the regular role of Nikki Bell, secretary to Mike Longstreet, a blind insurance investigator, in a new ABC Television Network series, "Longstreet," which bows on THURSDAY, SEPT. 16 (9:00-10:00 p.m., EDT). The series stars James Franciscus in the title role of Longstreet, and Peter Mark Richman as his friend, Duke Paige.