268 Marsh's Monograph on the Odontornithes 
anatomist, that some low character may persist while specializa- 
tion in certain directions is reaching a high degree of perfection. 
we leave out of account the skull and presacral vertebrae of 
this group, its structure is essentially that of a modern bird, but 
the combination of such specialized and primitive characters 
renders it not less remarkable than its larger toothed ally. 
4 x 
Figure 7.—Outline of the skull and brain-cavity of Jchthyornis victor, Marsh 
_.__ Seen from above ; five-sixths natural size. 5. eae 
Figure 8.—Outline of the skull and brain-cavity of Sterna cantiaca, Gmelin; : 
view ; natural size. 
ol. olfactory lobes; ¢. cerebral hemispheres ; op. optic lobes ; cb. cerebellum. a 
then be found with the wings and feet, yery strong evidence | 
