Splendid, too, is the performance of Yuri Tolubeyev, one of Russia's leading comedians, as Sancho Panza, the fat, grotesque ``squire.'' Though his character is broader and more comically rounded than the don, he gives it a firmness and toughness -- a sort of peasant dignity -- too. It is really as though the Russians have seen in this character the oftentimes underlying vitality and courage of supposed buffoons.

The episode in which Sancho Panza concludes the joke that is played on him when he is facetiously put in command of an ``island'' is one of the best in the film.

True, the pattern and flow of the drama have strong literary qualities that are a bit wearisome in the first half, before Don Quixote goes to the duke's court. But strength and poignancy develop thenceforth, and the windmill and deathbed episodes gather the threads of realization of the wonderfulness of the old boy.

There are other good representations of peasants and people of the court by actors who are finely costumed and magnificently photographed in this last of the Russian films to reach this country in the program of joint cultural exchange.

Also on the bill at the Fifty-fifth Street is a nice ten minute color film called ``Sunday in Greenwich Village,'' a tour of the haunts and joints.