318 



Kansas. Tlic, ray \s of (he compound character already described as belong- 

 ing to otlier genera of this family ; its edge is not preserved. 



The maxillary hones are subtriangular in form, and support three or four 

 large lancet-shaped teeth at the middle of their length. There are no teeth 

 beyond them ; but, on the deeper side, there are several small lancet-shaped 

 teeth. The outer alveolar edge Is rugose. The teeth are very flat, acute, and 

 perfectly smooth. The teeth on the greater part of the dentary are interme- 

 diate in size between the large and small ones of the maxillaries ; they stand 

 on the outer edge of a broad horizontal alveolar plane. There are three large 

 teeth in a series at the end of the dentary on the outer side ; they have been 

 lost, but their bases are broader ovals than those of the maxillary bone. On 

 the middle line of this part of the dentary is a close series of small com- 

 pressed teeth with striate enamel, standing on a ridge of the bone ; they leave 

 the last large tooth to the outer side, while on the inner side stand two or 

 three lancet-shaped tusks of a short row farther back. Posterior deutaries 



0'"'".10 apart. 



Measurements. 



M. 



Lougth of tlio maxillary boue above 0.088 



Depth proxlmally 0. 030 



LougtU of the crowu of a large tooth 0.0150 



Width of the crowu at the base 0. 00G5 



Lcugth of the hyomaiulibular 0. 1000 



In size this fish exceeded all of the SaurodontidcB excepting the large 

 species of Portheus. 



Niobrara epoch of Phillips County, Kansas. 

 Discovered by Prof B. F. Mudge. 



STRATODONTIDJE. 



In this group, I have arranged several genera, which resemble Enchodus, 

 the longest known of its forms. They are physostomous fishes, as indicated 

 by the relations of bones of the superior arch of the mouth, the absence of 

 spinous dorsal radii, the cycloid scales, and the general relationship to Esox. 

 Agassiz and others have regarded some of them as allied to Sphj/rcena. This 

 opinion was probably derived from a consideration of the forms of the teeth, 

 which, to some degree, resemble those of Sphyrcenidm and Trkhiuridce. 

 This is, however, like many other minor characters, one of those which appear 

 in both of the great groups of osseous fishes. 



In all of the genera, the maxillary l)one is well developed, and supports 



