PLATE VI. 



LOWER JAW OF TRICERATOPS SULCATUS MARSH. 



(See p. 30.) 

 Plate prepared under the direction o{ Marsh. 



Specimen No. 4276, TJ. S. National Museum. 

 Fig. 1. Superior view. 

 Fig. 2. Internal view. 

 Fig. 3. External view. 



ang, Angular; art, articular; cp, coronoid process; d, dentary; s, splcnial; sang, surangular. 

 One-sixth natural size. 



210 



