Fossil Bone for ID

[IndianRiverSonrise]

I found the following fossil bone today. It is about four inches long. Oval on one end, and Y shaped on the other. About 2.5 inches across. I have a ruler in some photos to make the size comparisons.

Any ideas appreciated. Thanks.

 

[Worthy55]

It looks like turtle shell to me. 8) 8) 8)