2 THE CERATOPSIA 



University of Kansas for information concerning the Triceratops skull there, and to Mr. E. S. Riggs 

 of the Field Museum of Natural History and Mr. F. W. Kohler of the Carnegie Museum for similar 

 aid, as well as to the Field Museum itself for the privilege of reproducing Charles W. Knight's 

 mural of Protoceratofs, which forms the frontispiece. Mr. J. A. Allan of the University of Alberta 

 has kindly furnished the photograph of Chasmosaurus reproduced in Plate VII B. 



Messrs. T. W. Stanton and L. S. Russell furnished valuable information regarding strati- 

 graphy, and Mr. Roy L. Moodie graciously diagnosed and described the diseased squamosal of 

 Torosaurus. 



Miss Clara M. LeVene has edited the memoir, and Miss Nelda E. Wright, Research Assistant, 

 has aided most efficiently in every way, preparing all of the text figures, with one or two exceptions, 

 and seeing the manuscript through the press. 



