The Mesh branch of the main tree view shows the regions of the imported meshes arranged in a hierarchy for each loaded mesh file. You can also view regions arranged in a hierarchy based on composite regions and mesh assemblies. To view either hierarchy in a separate Mesh tree view, right-click Mesh (from the Mesh branch of the main tree view) and select one of the View by submenu commands.

When viewing the file-based hierarchy, each imported mesh forms one or more assemblies at the first level of the tree. The second level of the tree shows all 3D primitives and the third level shows