Rogue Folder Appears

I have created two folders in my Lightroom catalog, one named "Lightroom" and the other "Master Catalog Overflow".  Lighroom is on my main computer, Master Catalog Oveflow is on a secondary NAS hard drive.  All of a sudden a new Master Catalog Overflow folder has appeared and recent additional subfolders/images meant for the original MC Overflow have been installed on the duplcate folder.  However, when looking at my file directory in Finder MAC-OS, there is only one MC Overflow file, leading be to believe this is a Lightroom issue.  I've had the dual folder system for some time and never have seen this before.  Thoughts?