Was that the New York City Ballet dancing at the Kennedy Center last night? Not that there was a breach of style or lapse in skill, but the absence of many familiar faces (and bodies) in leading roles made one notice how suddenly a new generation has come to reign. There has been no revolution; most of the newly prominent dancers have risen through the ranks. Yet the clearest sign of a new era was Peter Martins' listing in the program. The company's Apollonian danseur was the predominant choreographer on the bill, with two ballets to George Balanchine's one.

Martins is still a new choreographer, but with as good an education as can be obtained. He's not the sort who spills motion onto the stage in inspired disarray. Best of all, Martins showed last night that he has the freedom to work in more than one style.

"The Magic Flute" is Martins' re-creation of a 90-year-old Russian ballet, complete with Riccardo Drigo's mild score, and a too-familar story about the course of true love in the face of avaricous parents and a good spirit. To the choreographer's credit, the dances never seem to clash with the period atmosphere, although they have the energy of contemporary classicism. The work is flawed in its timing and consistency of characterizations. Nice dance ideas are often rushed, and several of the mimes are so busy pursuing the action that they establish themselves as personages only in asides. Some emerge as gross caricatures, others show signs of being flesh and blood, and this hampers the progress of the thin plot. Katrina Killian, bright and brittle in her dancing, was a stereotyped ingenue, but David McNaughton gave a strong whiff of country air to his impersonation of her sweetheart. His pudginess does not impede a powerful impetus and pliant motion.

Martins' "Concerto for Two Solo Pianos" is a Stravinsky ballet in the fragmented classical manner. Heather Watts has the grateful central role, based on such notions as heels down-walking, pelvic play and kinkily eloquent arm gestures. Her two partners, Ib Andersen and Jock Soto, are very different dancers. Andersen is clear and light, Soto's dancing has gravity and fluidity. These qualities, though, are not used in their almost identical roles. Only in Watts' reaction to them does the difference show. She is compact when dancing with Andersen, laid-back with Soto. Also on stage are a busy female corps and the two pianos. The work needs paring down, and it had the misfortune of coming after "The Four Temperaments," one of the first and still finest examples of splitting the academic technique.

There were fine performances in "Four Temperaments." Victor Castelli is showing a new maturity, Mel Tomlinson's arms have the gift of gab, Stephanie Saland knows the value of a quiet instant, and Florence Fitzgerald's dignity was a surprise after her hamming of the mother in "Magic Flute."