I'm not aware of a way to make them show in the list, but you could just type smb://servername/sharename$ in that box, if you know the name of the share.
In that initial Connect to Server window, you can also click the + icon to bookmark it in the list below the text field. That way, you don't have to type it every time.
Alternately, if you have a bunch of them that you mount together, you can create an Automator script that will mount them for you, provided you know the share name for each. I wrote about that option in an answer to another question back in October.