CHAPTER XII. 



THE WINGS OF ICHTHYORNIS AND APATORNIS. 



(Plates XXIV-XXVI and XXX-XXXI.) 



The wings in the two genera of Odontotomy clearly indicate very 

 strong power of flight, thus differing as widely as possible from the corres- 

 ponding parts in Hesperornis. In Ichtliyornis, nearly all . the bones of the 

 wings are well preserved, and these are all remarkably like those of some 

 carinate birds living to-day. These remains give but slight indications 

 of the reptilian features seen in the portions of the skeleton already 

 described. 



The Humerus. (Plates XXIV and XXX.) 

 The humerus in Ichtliyornis is strong and well developed, thus differing 

 widely from that of Hesperornis. The most striking feature of the bone 

 is the enormous radial crest, surpassing in comparative size that of any 

 living bird. It is well shown on Plate XXIV, figure 3, re. This crest is, 

 moreover, remarkable for its position, which is in a plane nearly parallel 

 with the long axis of the head of the humerus, instead of considerably 

 inclined to this axis, as in most birds. This fact is clearly shown by a 

 number of well preserved examples, including the type specimen of 

 Ichtliyornis dispar (number 1450). In these two points, the humerus of 

 Ichtliyornis strongly resembles the corresponding bone in the Pterodactyles. 



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