I'm not certain, but it does resemble the tibia on a human. That's the bone between the front of the knee and the foot. The articulating ends (parts that meet with joints) are the right shape. Upper leg bones have a ball-shaped end to fit into the sockets, the other leg and arm bones are somewhat curved. The foot bones would be too tiny to see in a ferret. Penny-sized would be about right for a ferret leg. Of course, I do humans, not ferrets, so I could be wrong about the precise bone. Sandra [Posted in FML 5852]