Each scene displayer node provides access to the mesh representations that currently exist. To change the current representation, select the scene displayer node of interest (e.g. Geometry 1) and then click on the Representation option in the expert Properties window. The currently available mesh representations will be listed in the pull-down menu.
Select the appropriate mesh representation from the list and the scene will be updated with the new mesh. You should note that any other scene displayer nodes (e.g. Outline) for the same scene will not have the same representation selected for them - these should also be updated using the same technique as described above.