PLATE XCI 



Skull of Brontops dispar 



Plate prepared under the direction of Professor Marsh. One-fourth natural size. (See pp. 489, 490) 



Nat. Mus. 4290, skull K, Big Badlands, S. Dak., Titanoiherium zone, level middle B (J. B. Hatcher). Referred male skull, type of 

 B. validiis. Vertical crushing has lessened the vertical diameters of the skull top and tilted the horns upward and backward. 

 The skull is very robust and braohy cephalic. The stout horns are rounded in section, with a rugose area at the tip for the 

 attachment of the thickened epidermal cap. The general conformation of the skull, especially of the nasals and horns, suggests 

 possible ancestry to B. robustus. 



