The incus (anvil) bone is an anvil-shaped small bone in the middle ear. It connects the malleus to the stapes. This bone was first described by Alessandro Achillini of Bologna. This bone also transmits sound vibrations from the malleus to the stapes. The incus bone is only found in mammals.
The bone, which is derived from a reptilian upper jaw bone (the quadrate bone), embryologically derives from the first pharyngeal arch along with the rest of the bones of mastication, such as the maxilla and mandible.
Image Caption: Incus Bone. Credit: Wikipedia