766 



TITANOTHERES OF .VNCIENT WYOMING, DAKOTA, AND NEBRASKLl 



C V^^x^^* D 



Figure 695. — Skulls of Eocene oondylarth (Phenacodus) and perissodactyls 

 Reconstructed from materials in the American Museum of Natural History. Top views. All figures two-fifths natural size. 



A, Phenacodus (Phenacodontidae), lower Eocene. E, Isedolophvs (Tapiridae), middle Eocene. 



B, EoMppus (F.quidae), lower Eocene (first stage). 



Systemoion (Tapiridae), lower Eocene (first stage). 

 D, Eotilanops (Brontotheriidae), lower Eocene. 



F, Hyrachyus (Hyrachyinae), middle Eocene. 



G, Eomoropus (Chalieotheriidae), upper Eocene. 

 H, Triplopus (Hyracodontidae), upper Eocene. 



