... FLY is a public domain parallel treecode, which makes heavy use of the one-sided communication paradigm to handle the management of the tree structure. ... This paper shows an example of the integration of a tree N-body code with an adaptive mesh, following the PARAMESH scheme. This new implementation will allow the FLY output, and more generally any binary output, to be used with any hydrodynamics code that adopts the PARAMESH data structure, to study compressible flow problems. ...