The Mischa Tour 1990: Mikhail Baryshnikov will dance in the United States for the first time this year during an 18-city tour starting Oct. 24. The tour will be called the White Oak Dance Project. Dances, including two new ones, will be by modern dance choreographer Mark Morris. Other dancers include Peggy Baker and Nancy Colahan from the Lubovitch company, Jamie Bishton of Ballet Theatre and Kate Johnson from the Paul Taylor Dance Company. The troupe will perform in several cities, but no West Coast appearances have been planned.