EXPLANATION OF PLATES. 



PLATE V. — Life restoration of Hesperornis regalis Marsh. Drawn by Sydney 

 Prentice. 



PLATE VI. — Skeleton of Hesperornis regalis Marsh. After Marsh. 



PLATE VII. — Figs. 1, 2, jaws of Ichthyornis dispar Marsh, twice natural size ; 

 3, i, cervical vertebra of same, twice natural size ; 5, 6, mandible of Hes- 

 perornis regalis Marsh, half natural size; 7, 8, vertebra of same, natural 

 size; 9, tooth of same, much enlarged. All after Marsh. 



PLATE VIII. — Photograph of scutes and feather impressions of the tarsal re- 

 gion of Hesperornis species, from a specimen in the University of Kansas 

 museum. Enlarged. 



