Yes, the rail goes on the mount, and any rings for a 1913/picatinny rail will then fit on the rail.
I don't know if rings are available that bolt directly to the mount and can be used with a 1" or 30mm scope. Even if such rings are available, you wouldn't have any ability to control the position of the scope, meaning eye relief would be a crapshoot. With the rail adapter, you can move the scope exactly where you want it.