Debussy called "La mer" "three symphonic sketches," deliberately avoiding the term symphony. Simon Trezise, in his book "Debussy: La Mer", comments, "He had not composed an orthodox symphony, but neither did he want "La mer" to be known as a symphonic poem ... by calling it 'Three symphonic sketches' ... must have felt that he had deftly avoided association with either genre." Yet the work has sometimes been called a symphony, even on occasion, by Debussy himself. It consists of two powerful outer movements framing a lighter, faster piece which acts as a type of scherzo. But the analyst Jean Barraqué describes "La mer" as the first work to have an "open" form – a "devenir" "sonore" or "sonorous becoming... a developmental process in which the very notions of exposition and development coexist in an uninterrupted burst." Simon Trezise, in his 1994 book "Debussy: La Mer" comments, "motifs are constantly propagated by derivation from earlier motifs"