Explanation of Plates. 



Plate Ylll—Tillotherium fodiens Marsh. Figure 1, sid 



lower jaw, side view; figure 3, top viewc 



Plate IX— Figure 1. 



natural size ; figure 2, bot 

 size ; figure 3, ungual pha 

 side view ; natural size. 



miTwr Marsh. {Trogosus c 



