I found this skull laying under some leaves beside the fence in my backyard. We've seen lots of wood rats at night out there so that's what I assume it is. It was an inch and three quarters long (or 4.45 cm). The last picture is at an angle so you can see inside.
We have a lot of firewood stacked behind the shed where I found it and a lot of bay laurel trees. There's one tree that produces lots of drupes I haven't been able to identify and a garden a yard over.
Pictures taken with an iPhone 5.