BIG BADLANDS OF SOUTH DAKOTA. 



481 



posteroexternal face, and the lower canine has a well-defined groove 

 worn on the posterior side at the base of the crown. ... It is out 



y..B6 



Fig. II. Scaptohyus altidens gen. et sp. nov. Holotype, No. 11161. Front 

 of skull from the right side, about 0.26 natural size. Drawn from photograph 

 and the specimen. 



of the question to suppose that these grooves and notches could 

 have been produced by abrasion with other teeth, for no other teeth 

 could reach the worn areas, and it is altogether probable that they 



Fig. 13. 



Fig. 12. Scaptohyus altidens gen. et sp. nov. Holotype, No. 11161. 

 Fragment of the dependent process of the left jugal, one sixth natural size. 



Fig. 13. Scaptohyus altidens gen. et sp. nov. Holotype, No. 11 161. Upper 

 and lower incisors and canines showing the grooves worn by root-digging, 

 one third the natural size. 



