594 



COLLEGE ZOOLOGY 



bird-like characteristics predominate over the reptilian features 

 so that this curious creature is placed in the class Aves, although 

 it is a connecting link between the birds and the reptiles. 

 Subclass II. Neornithes. — Recent Birds. 

 Order i. Hesperornithiformes. — There are three species of 

 fossil birds in this order. Hesperomis regalis (Fig. 478), the best- 

 known species, was 

 nearly four feet in 

 length. It possessed 

 teeth set in a groove, 

 strong hind limbs 

 with webbed feet, 

 which were used like 

 oars, and a sternum 

 without a keel. The 

 entire anatomy indi- 

 cates that Hcspcror- 

 nis was a flightless, 

 swimming and diving 

 bird which lived upon 

 fishes and other 

 aquatic animals. 

 The remains of this 

 and the two other 

 species probably be- 

 longing to this order 

 were found in the 

 Cretaceous deposits 

 of Kansas. 

 Order 2. Ichthyornithiformes. — Of the dozen or more 

 species of fossil birds included in this order, Ichthyornis victor 

 (Fig. 479) from the Cretaceous deposits of Kansas, is the best 

 known. This bird had teeth set in sockets, a keeled sternum, 

 and well-developed wings. It was about the size of a pigeon, 

 was a strong flier, and probably fed upon fish. 





Fig 479. — Ichthyornis victor. 

 after Marsh.) 



(From Zittel 



