Stewart.] Cretaceous Fishes. 325 



material will have to be examined before this can be accurately 

 determined. The teeth are compressed and appear minutely 

 striated under the microscope. From the center to the anterior 

 extremity of the dentary the teeth decrease in size, while those 

 on the posterior portion are nearly twice the size of those on the 

 maxilla. Spaces for about forty-two are present, but quite a 

 number of the teeth seem to have been shed and never replaced, 

 as the alveoli seem to be entirely closed in some instances. 



The dermarticular sends a long, dagger-like process forward 

 internally nearly to the ovoid pit mentioned above ; externally 

 it is soon covered by the dentary. The cotylus is somewhat 

 vertically directed, narrow laterally, and slightly convex from 

 above downward. 



The predentary is a triangular element joined to the dentary 

 by a very irregular surface, broader above than below. The 

 superior border is finely rugose and edentulous, and the tip is 

 acute. This bone is unpaired, as in Saurodon. 



Length of maxilla and premaxilla 161.5 mm. 



Depth of bone posterior to condyle for the palatine 44.5 " 



Height of condyle for palatine above the alveolar border. ... 48. 5 " 



Length of premaxilla. inferiorly 31.5 " 



Average height of crown 3.9 " 



Average anterior posterior length of crown 3.3 " 



Number of teeth in one inch, 9. 



Mandible: Length. from cotylus 161.0 mm. 



Length of alveolar border 140.0 " 



Depth of predental surface | estimated ) 33.0 " 



Average height of crown, posterior 6.0 " 



Average length of crown, posterior 4.4 " 



Predentary: Length 29.5 " 



Depth 34.0 " 



