16 

 4. General Eelations of the Fauna. * 



FISHES. 



The fishes include trvily marine as weli as biackish and fresli- water types, and are 

 all of Montana and Alberta reference. 



Mykdaphus and MyJognalhvx, are marine sharks, supposedly related to the modern 

 Chimasroids (Holocephala) ; Hedronchus slernbergi ("Fort Union," Montana) is similarly 

 referred by Dr. Hay, although with much doubt. Two species of Dipnoans, Ceratodus 

 hierogli/phus and C. (Rliineastes) eruciferits are also from the Montana and Belly River 

 beds. The sturgeons are somewhat doubtfully represented in the new species Acipenser 

 albertensis from the Belly Kiver ; this may prove to be nearer Lepidosleus, a genus which 

 is certainly represented in the Le/iidotus occidentalis of Leidy, (Judith and Belly Elver). 



The relationships of the new genus and species Diphyodus longirostris are entirely 

 problematical. 



BATRACHIA. 



Cope has described five species of batrachia, all from the Judith River beds, belong- 

 iuo- to the^two Urodele genera Scapherpeton and Heniilrypus, of doubtful family relation- 

 ship. One species S. tectum has been determined by Mr. Lambe in the Belly River. 



No batrachians are recorded from the "Wyoming Laramie. 



REPTILIA. 



Plesios.vurs. Numerous vertebrae of a large plesiosaur from the Belly River are 

 provisionally referred to the New Jersey species Cimol.iasaurus magnus, Leidy. From 

 Moreau river, South Dakota, Leidy has described two Plesiosaurs, Nothosaurops occiduus 

 and Ischyrosaurtts antiquus ; whether these beds are of Belly River age or more recent is 

 not known. Uronautes cetiformis, Cope is another plesiosaur from the Judith River. 



Chelonia. Turtles of the sub-order Trto«i^c/*ut are abundant. One species, Tnow-ya; 

 foveatus, is common to the Judith and Belly River series ; another, T. vagans, to the Belly 

 River and supposed " Ft. Union " beds. 



Three other species, Plastomenus costatm, P. coalescens and P. punctulatus have been 

 named by Cope, the first two from the Laramie of the "badlands" south of "Wood 

 Mountain, Assiniboia, the third from the supposed " Ft. Union " (Judith River) of Mont- 

 ana. Dr. Hay observes that it is not unlikely that P. coalescens is a synonym of Trionyx 

 vagans ; P. rostatus and P. punctulatus are also more likely to belong to Trionyx. Plas- 

 tomenus is distinctively an Eocene genus. 



The order Crtptodira is represented by large swamp turtles related to the Dermatemy- 

 didce, but belonging to the family Adocidce. ; these are Adocus lineolatus, Cope, A. (Basilemys 

 or " royal turtle ", Hay) variolosus, and A. {Basilemys) imbricarius ; the royal turtle is very 

 large and elaborately sculptured. It is important to note that the two species first 

 named are found both in the Belly River and in Montana (? " Ft. Union " ), testifying to 

 the Mid-Cretaceous age of the latter. The presence of numerous species of the .Turassic 



*The writer is especially indebted to Dr. O.P. Hay of The American Museum for valuable notes, criticisms and suggestions 



on the systematic section of this introduction. 



