320 University Geological Survey of Kansas. 



posterior condyles above are somewhat elliptical in outline and 

 but slightly convex from before backwards. Just anterior to 

 this there is a large protuberance, which may support a condyle 

 above, and on the external side of this there is a small facet, 

 which probably gives articulation with the ethmoid. The sur- 

 face for the premaxillary is very irregular and is directed in- 

 ward, becoming thinner toward the anterior border, which is 

 sharp. The superior border is strongly concave and sharp, and 

 presents a sutural surface on the external side, probably for a 

 jugal. The alveolar border is convex and has alveoli for forty 

 or forty-one teeth, which are non-striate and knife-like. Each 

 tooth has the characteristic notch at the base. The posterior 

 extremity at the bone is very shallow and turned slightly up- 

 ward. Aside from the shagreened surface of the bone above 

 the alveolar border the external surface has no characteristic 

 markings. 



The premaxillary is very similar to that of the species de- 

 scribed above, except that there are ten instead of twelve teeth. 

 On the internal side, the bone is beveled off toward the pos- 

 terior border in order to fit the surface for its reception on the 

 maxillary. 



Maxillary : Length of alveolar border 115 mm. 



Depth at condyle for palatine 45 " 



Greatest length of bone 128 " 



Number of teeth in one centimeter, 3.5. 



Premaxillary : Depth 60 mm. 



Length 32 " 



The dentary is elongate and slender. The alveolar border is 

 slightly incurved at the symphysis and supports forty-six teeth , 

 similar in form but about twice as large as those upon the max- 

 illa. Just back of the last tooth there is a slight coronoid 

 process, somewhat similar to that found in Xiphactinus. The 

 symphysis is very similar to that found in the last species de- 

 scribed, and has a long, slender pit just back of it on the internal 

 side. It is more elliptical than the corresponding pit in Sauro- 

 cephalus. The lower border of the bone is sharp. 



The dermarticular supports only a small portion of the cotylus, 

 in the lower portion of the cavity. It sends a long, sword-shaped 



