SummaryFor better and for worse, modern linguistics when at all mathematical is mostly preoccupied with tree structure (or trivially equivalent structures such as labelled bracketings). This choice of representation is justified mainly by long tradition, and in view of the formal difficulties in transformational grammar alternatives should be seriously investigated. Especially, the use of more general graphs than trees should be at least attempted. A preliminary exploration of how graphs could be used with less prejudice in syntax strengthens the suspicion that trees are not necessarily the most adequate tools for describing sentence structure.