Friday afternoon and Friday evening in Symphony Hall, the last of this season's coreerts by the Boston Symphony Orchestra, Mr. Koussevitzky conducting. The programme embraces Bach's Brandenburg Concerto No. 3 for String Orchestra, his Adagio from the Toccata in C major. Scriabin's "Prometheus," Debussy's "Clouds" and "Festivals," and Borodin's Polootsian dances from "Prince Igor."

Sunday evening in Symphony Hall a recital by Feodor Chaliapin, the great Russian bass. As usual Mr. Chaliapin will announce his programme from the concert stage. He will be assisted by Abraham Sepkin, violinist, and Max Rabinovitsch, pianist.

Monday evening in Symphony Hall, the opening of the fortieth season of Pops concerts, which will continue every night except Sunday for two months. The orchestra is the Boston Symphony: the conductor Agide Jacchia. The programmes are made up of exeerps from the operas and of light and pleasing trifles.