xiii PHYLUM CHORDATA 413 



OKDER 1. STEREORNiTHES. 1 



Including Phororhacos, Dryornis, and other genera from the 

 Eocene of South America. 



FIG. 1053. Hesperornis regalis. The restored skeleton. (After Marsh.) 



ORDER 2. ODONTOLCLE. 



Including Hesperornis 2 (Fig. 1053), a large diving and swimming 

 Bird from the Cretaceous of North America, and other less known 

 genera. 



1 Recent investigations indicate that this is not a natural group, but that its 

 various genera will have to be distributed amongst various orders both of 

 Ratitre and of Carinatse. 



2 Hesperornis is perhaps more nearly related to the Ratitee. 



