I don't know who made these plates that I inherited quite some years ago.  They need to be cleaned up, which I haven't done as I'm afraid I might break them. Each plate measures appx 8½" across.  They were made before WWII as the back of the plates say "Germany" and I know they're much older than the reunification is.
I haven't a clue as to what these are worth.  If anyone knows anything about these plates, please let me know.  Thanks!

Some sort of funky bird

Back of the above plate

This I know!  A Mallard Duck

Back of the above plate

Quail or Grouse, or some such

Back of the above plate