186 PROCEEDINGS OF THE NATIONAL MUSEUM vol.83 



DiNosAuRiA — Continued. 

 Deinodoutidae : 



Gorgosaurus sp. 

 Nodosauridae : 



Armored dinosaurs. 

 Chelonia : 



Pleurosteruidae : 



Neurankylus haueri Gilmore. 

 Baenidae : 



Bacna nodosa Gilmore. 



Baena ornata, new species. 



Baena sp. 



Thescel'its hemispherica, new species. 



Boremys grand w, new species. 

 Dermatemydidae : 



Basilemys nobilis Hay. 



Adocus bossi Gilmore. 



Adocus kirtlandius Gilmore. 

 Trionychidae : 



Plastomcnus robustus Gilmore. 



Plastomentts sp. 



Aspidcretcs ovatus, new species. 



Aspidcretes vorax Hay. 



Dinosaurian reptiles were the predominating vertebrates of this 

 time, and they afford the most reliable information for correlation 

 with those Upper Cretaceous faunas found elsewhere in North 

 America. Representatives of four families have now been recog- 

 nized : Deinodontidae, Hadrosauridae, Ceratopsidae, and Nodosauri- 

 dae. The Deinodontidae are represented by a dentary not distin- 

 guishable from the corresponding bone of Gorgosaurus^ known else- 

 where only from the Belly River formation. That other members 

 of this family are present is indicated by fragmentary remains none 

 of which is generically identifiable. The Hadrosauridae are repre- 

 sented by the genera Parasaurolophus and Kritosaurus^ both of which 

 occur elsewhere only in the Belly River of Canada; the Ceratopsi- 

 dae by the genus Pentaceratops and a chasmosaurid, the latter also 

 a Belly River form, but its occurrence in the Kirtland needs addi- 

 tional verification before we can be positive of its assignment. Lull 

 (1933) regards the genus Pentaceratops as having a more advanced 

 stage of horn development than is found among the Belly River 

 ceratopsians and finds its nearest complement in those of the Edmon- 

 ton. In the light of the recently described Chasmosaurus kaisenl 

 (Brown, 1933), from the Belly River, with tall brow horns and 

 well-developed nasal horn, it would seem to me this conclusion no 

 longer applies. 



The evidence furnished by the known Dinosauria is overwhelm- 

 ingly in favor of regarding the Kirtland formation as equivalent to 

 the Belly River of Canada, as previously suggested by Brown and 



