PLATE XIII. 



LEFT ULNA OF TRICERATOPS PRORSUS MARSH. 



(See p. 60.) 

 Plate prepared under the direction of Marsh. 



Specimen No. 4S42, U. S. National Museum. 

 Fig. 1. Posterior view. 

 Fig. 2. Internal view. 

 Fig. 3. Proximal view. 

 Fig. 4. Distal view. 

 Fig. 5. External view. 

 Fig. 6. Anterior view. 

 Fig. 7. Section of shaft. 

 One-fourth natural size. 



224 



