The one in the silver hunter's style case is a LaJour and probably fairly modern. I think the back unscrews (I wanted to see the works and serial number), but I turn and turn it but the back won't come off. Also, the cover won't stay shut.
The one in the open face gold case is a Hampden. The back opens on a hinge, but under the outer case is another backing I'm not sure how to open, either.
Any opinions on these (without seeing the innards)? I may follow up later with more photos if I take them to a local jeweler to show me how to open them - I don't want to force anything.