Why did the viola player stare at the music sheet for hours? It was a rest.
Half the viola section got lost on page two.
Orchestra director: 'Violas, please play measure 32.' Violist: 'What page is that on?' Director: 'It's the only measure on that page.'
Why did the violist study alto clef? They gave up on reading treble and bass clef, so they invented a third option to fail at.

