The Pops concerts, made famous through their 41 years of performances, have their official opening tonight in Symphony Hall at 8.15 o'clock under the direction of the new conductor, Alfredo Casella. Their program tonight will be: Prelude to "Carmen" Bizet Two Marches Schubert Arranged for orchestra by Casella First performance in America "Fountains of Rome," Symphonic Poem Respighi Prelude to "The Mastersingers of Nuremberg" Wagner Overture to "Cinderella" Rossini Three Dances from "Othella" Verdi "Italia" Rhapeody Casella Indian War Dance Skitton Valse Triste Stbelius Caprice on Spanish Themes Rimsky-Korsakov