DirectoryIterator scan to exclude '.' and '..' directories still including them?

Question

In the script below, I'm trying to copy the folders that exist in the $base directory over to the $target directory. However, in my initial echo test, its returning the . and .. directories even though I'm trying to handle that exception in the conditional.

What am I missing?

    $base = dirname(__FILE__).'/themes/';
    $target = dirname( STYLESHEETPATH );
    $directory_folders = new DirectoryIterator($base); 
    foreach ($directory_folders as $folder) 
    {
         if ($folder->getPath() !== '.' && $folder->getPath() !=='..' ) 
         {
            echo '<br>getPathname: '. $folder->getPathname();
            //copy($folder->getPathname(), $target);
         }
    }die;

However, and this makes no sense to me, if I change the conditional to...

         if (!is_dir($folder) && $folder->getPath() !== '.' && $folder->getPath() !=='..' ) 

It returns the correct folders inside of $base. What?