FIGURE 11. Middle ear ossicles (left malleus and incus) dissected from the skulls of several heteromyids compared with fossil ossicles of Prodipodomys. At upper left, modern Chaetodipus intermedius; upper right, modern Microdipodops pallidus; lower left, Pliocene Prodipodomys idahoensis from MNA locality 318; lower right, modern Dipodomys merriami. The ossicles are articulated in the modern specimens.