Stewart.] Cretaceous Fishes. 299 



directed slightly inward. The symphysis is much thickened 

 and was about the same slope as that of /. anaides. Just back 

 of the hook-like process mentioned above the alveolar border 

 is somewhat excavated, and back of this slightly convex for a 

 distance of 55 mm., when it is directed slightly upward. The 

 teeth are closely set with elliptical crowns, the long axis of 

 which is placed obliquely to the tooth line. 



Dentary : Length of alveolar border ( estimated ) 125 . mm. 



Length of long axis of cross-section of tooth 4.5 " 



Length of short axis of cross-section of tooth 3.0 " 



Number of teeth in one centimeter 3 



The hyomandibular shows the anterior and posterior portions 

 of the superior condyle to be more robust and the central por- 

 tion to be more concave than in Xipliactinus. The condyle for 

 the operculum is also proportionally longer and not projected 

 backward so far as in the above. The groove for the preoper- 

 culum is deep. 



Hyomandibular : Length of superior condyle 35 mm. 



Length of condyle for the operculum 30 " 



Total length of bone (estimated) 115 " 



Length of groove for the preoperculum (est.) . 93 " 



The preoperculars are preserved in part. They are rather 

 thick on the anterior border and are probably projected forward 

 to the angle of the mandible below. Superiorly, there is a long, 

 slender process of bone extending upward, which is much more 

 prominent than in the corresponding portion of Xipliactinus. 

 This portion is somewhat roughly striated externally. The re- 

 maining portion of the external surface is nearly smooth, ex- 

 cepting along the superior border, where there are numerous 

 striae leading out to the border. 



The malleolar portion of the palatine is rather thin in a ver- 

 tical direction, resembling J. anaides somewhat in this respect. 

 The inferior articular surface has the same general outline as 

 the posterior condyle of the maxilla. Anterior to this, the bone 

 is beveled off antero-superiorly, causing the prefrontal articular 

 surface to be produced forward beyond the inferior. This sur- 

 face is nearly flat. On the external side of the bone there is a 

 prominent tuberosity. 



