

UNITED STATES GEOLOGICAL SURVEY 



CHARLES D. WALCOTT, Director 



THE CERATOPSIA 



by 

 JOHN B. HATCHER 



BASED OlST PRELIMINARY STUDIES BY 



OTHNIEL C. MARSH 



EDITED AND COMPLETED BY 



RICHARD S. LULL 



.. J6k 



WASHINGTON 



GOVERNMENT PRINTING OFFICE 



19 7 



