Don't know the species of the smaller one, but it looks like it could be a rabbit of some sort. They have a lot of fenestration in their skulls. Also if you look at the incisors, they should have another smaller set of them being the larger ones. (Think that's true for most rabbits)
hmm, I don't know. I'll have to have a closer look at it. 
I thought they looked like cat and rabbit skulls.
After googling an image of a rabbit skull it does look like it could be, good eye!
They make a good stew...