

A V ES 



CLASS IV 



Super Order 1. ODONTOLCAE. 1 



Birds with teeth implanted in a continuous groove ; mandibular rami united at 



symphysis by ligament only, and with their component bones free from one another. 



Clavicles fret from one another. Basipterygoid processes wanting; palatal structure 



impt rfectly knovm, but the head of the quadrate is single and the vomer is probably 



paii H<wt.< of pelvis free posteriorly ; vertebral articulations saddle-shaped. 



The order Hesperornithes contains members of the genus Hesperomis (Figs. 

 362, 363, 'MiS) and their allies from the Upper Cretaceous of Kansas. So far 



Fio. 368. 

 egalis, Marsh. Upper Cretaceous ; Kansas. Restoration of skeleton, i/ 8 (after Marsh). 



as is known the teeth in the upper mandible were confined to the maxilla, for 



Marsh, <>. C, Odontornithes : A Monograph on the Extinct Toothed Birds of North America. 

 Washington, 1880. -Williston, S. II'.. Plumage of Hesperornis (Kan. Univ. Quart, vol. V. p. 

 . I 396. 



