76 ELEMENTS OF COMPARATIVE ZOOLOGY. 



smaller being about the size of a crow, the other somewhat 

 larger. They are called Archaeopteryx, 



SUBCLASS II. ODOKTOKNITHES (Toothed Birds). 



These forms, which have been found only in American 

 rocks, are more like modern birds than is Archaeopteryx, 



FIG. 29. Skeleton of Wingless Toothed Bird (Hesperornis). From Marsh. 



but they differ from all existing birds in having teeth. 

 They had normal tails, and one form apparently was wing- 



