Stewart.] Cretaceous Fishes, 323 



of the maxillae at about the point where the pterygoid should 

 lie, but it is too large to be a portion of this bone. There are 

 nine teeth upon it, which are about the size of those on the 

 anterior portion of the maxilla. 



The type of the above was found in Gove county, Kansas, by 

 Mr. YV. 0. Bourn, of Scott, Kan., who loaned it to the Univer- 

 sity for study. 



SAUROCEPHALUS. 



Harlan, Jour. Acad. Nat. Sci. Phil., vol. Ill, p. 337. 



Saurocephalus is similar in many respects to the genus just de- 

 scribed. Unfortunately the skull has never been found in either 

 this country or England, but from the great similarity of the 

 jaws to those of Saurodon a close relationship in general struc- 

 ture to this form can be expected. In Saurocephalus the mandi- 

 bles are not so slender as in Saurodon, and do not project forward 

 as in this form. There are distinct foramina instead of deep 

 notches below the alveolar border internally, and the teeth have 

 very short and compressed crowns instead of the subcylindric, 

 knife-like crowns of Saurodon. 



Thus far four species have been described from America, as 

 follow> : 



Saurocephalus lanciformis Harlan, Cretaceous, Missouri river. 

 Saurocephalus arapahovius Cope, Niobrara Cretaceous, western Kansas. 



irocephalua dentatua Stewart, Niobrara Cretaceous, western Kansas. 



rocephalus pamphagua Hay, Niobrara Cretaceous, western Kansas. 



Thus it is seen that only three species have thus far been dis- 

 covered in this state, of which one, fi>. arapahovius, was founded 

 upon only a small portion of a maxilla which presents but few 

 characters that can be called specific. It is very hard to refer 

 specimens to this species with any degree of certainty, and I 

 am inclined to think that it may prove to be a synonym of £. 

 lanciformis. 



Saurocephalus dentatus. Plate LVIII, 3a and b, 4a and b. 



Saurocephalus dentatua Stewart, Kans. Univ. Quart, vol. vn, pp. 25 27. 



This species differs from S. arapahovius in having the teeth 

 slightly striated and never overlapping on the maxilla. It is 

 also a slightly larger form. It was established upon the left 



