weird "three way circuit"

[nomorecall]

I replaced the old, mismatched switches in our home so they "look nicer," according to Wifey. One three-way in the living room (to ceiling spots) had a single pole on one end and a 3-way switch on the other. I see no obviously loose "traveler" wire in the single pole box but I can't imagine this was meant to be..

Any suggestions as to how to correct? I'm fairly handy (added circuits, single gang to double, etc.) but I'm scratching my head on this one...a diagram is attached for reference.

Thanks in advance!