600 R. W. SHUFELDT 



the culmen of the superior mandible has a uniform curve from 

 the craniofacial hinge to the rather sharp apex; in fact, the upper 

 bill as a whole slopes away to its tip in a gentle forward and 

 downward direction. Laterally, the small narial aperture is 

 rather irregular in outline and is situated about half way between 

 the anterior margin of the orbit and the distal apex of the beak. 



The V-shaped mandible is nearly uniform in depth from its 

 articulation to its symphysis, which latter is truncate from the 

 terminal point, downwards and backwards. 



Either orbit is subcircular in outline and possesses a very sharp 

 margin for the entire arc of its superior periphery. Anteriorly, 

 the pars plana is complete. Even at this early stage the inter- 

 orbital septum is entire for its whole extent; the nerve foramina 

 on its posterior joining with the anterior wall of the brain-case 

 are small, being only of sufficient size to admit of the passage of 

 the nerves tlii'ough them. Even the floor of this orbit is more or 

 less complete, made so by the close articulation of the palatine 

 of the same side, and, in part, by the breadth of the corre- 

 sponding quadrate bone and also, to some extent, the pterygoid. 



Externally, the vault of the cranium is rounded and smooth, 

 being but slightly depressed between the orbits mesially and in 

 front; and the nasals extend well backwards, their posterior 

 apices in the middle coming in contact opposite the center of the 

 orbits. 



The basis cranii is in the horizontal plane and the condyle is 

 of considerable size. 



In the vertebral column there are seventeen cervical vertebrae 

 in the skeleton of the neck, and of these the last two, the six- 

 teenth and seventeenth, support a pair of free ribs. These ribs 

 lack unciform processes, while those of the three dorsal pairs 

 of ribs are peculiar in that they are elongate, nonprojecting 

 backwards, and more or less adpressed anteriorly to the posterior 

 margin of the rib in all cases. This is also the case with the 

 anterior pair of pelvic ribs. 



The dorsal vertebrae are closely articulated with each other, 

 the neural spines being low, and, in their present cartilaginous 

 state, appear to be almost blended with each other. No haemal 



