PLATE XCIX 



Type Skull and Jaw of Brontops robustxjs 



Plate prepared under the direction of Professor Marsh. One-fourth natural size. (See p. 494, also Pis. XCVI-XCVIII) 



Yale Mus. 12048, Dry Creek, 5 miles northeast of Chadron, Nebr. (J. B. Hatcher), Chadron formation, probably upper levels. 

 The front view of the skull, compared with that of Brontops dispar (PL XCIV), shows the increased specialization in its greater 

 size and width, expanded zygomata, and thickened horns. 



