No. 433 ] CERTAIN GROUPS OF BIRDS. 



59 



most specialized genera of the moas seems to indicate that its 

 complete atrophy in the kiwi is simply to be looked upon as 

 an instance of the extreme specialization of that genus." 



I have thus fully quoted from T. J. Parker's views upon the 

 relationships of the ostriches and Apteryx for the reason that 

 they are important and useful in the present connection, and that 

 they are entertained by many other naturalists. It must be 

 remembered, however, that these views are drawn up after an 

 examination of the bony skulls alone, or very nearly alone. It 

 must be borne in mind, too, that Marsh endeavored to make 

 ostriches, or ratite birds, out of Hesperornis and Ichthyornis 

 simply because they possessed the ancient form of palate, and 

 that their ilia and ischia possessed free posterior extremities. 



I now pass to a consideration of the osteological characters of 

 the OdontoholcEe, the supersuborder to which the Hesperoni- 

 thidee belong. It will be necessary to reproduce my observa- 

 tions in order to properly set forth and support my scheme of 

 classification which, as I have already said, will be published 

 in the future. 



Supersuborder III. Odontoholoe. 



Pygopoformes. Hesperornithoidea. Hesperornithida;. 



Enaliornithidae. 



Fossil remains of upwards of fifty individuals representing 

 extinct species of the Hesperornithidae have been taken from 

 the Middle Cretaceous of Kansas and Colorado, where occurred 

 also Icthyornis (Order II) and its allies. Marsh also described 

 the bones of these great ancestral divers in his Odontonithes, 

 and left us a restoration of the skeleton of Hesperornis regalis. 

 This was not a difficult task for the reason that nearly perfect 

 skeletons of that form were deposited in the museum of Yale 

 College, and one of these was so complete that it lacked only 

 a very few unimportant bones, as the distal ungual phalanges of 

 two or three of the podal digits. 



Hesperornis regalis had a length of about six feet, and 



specimen wh 



attitude would have 



had a height of about three feet. The distinguished Scotch 



