There's No Place Like Home

Slug Duplex?

  I'm guessing that this is a nest  for one of the speckled behemoth slugs in our yard; the rainbow bright slime trail hardened to a sheer plastic is too familiar. Of course, I poked a stick in it to see what the inner white walls were.  It seemed rubberish. I wonder if there are any sane animals that eat these gross things.