An advance in method based on very thorough study of the musculature of the Perissodactyla has been adopted in restoring Eotitanops and Brontotherium as representing the first and the last stage of this great family of titanotheres. Dr. W. K. Gregory assisted by Mr. Erwin Christman undertook an exhaustive research on the myology of the titanotheres based on the detailed studies of the anatomy of the horse and tapir by Schmalz, Murie, Windle, Parsons, and others. On this basis the superficial musculature of Palæosyops and of Brontops has been almost completely restored, giving the special significance of all the areas of origin and insertion of the various muscles and tendons.
With this knowledge in hand, the restoration of Brontotherium was undertaken afresh and a very precise scale drawing of the skeleton of Brontops robustus was projected with the complete musculature. With these data the modeling of Eotitanops, a largely conjectural . . .