62 KNOWLTON 



paces from the Judith River of Fish Creek, Montana, have been 

 referred to this species by Doctor Hay, who makes the following 

 statement concerning them: "No characters are observed which 

 serve to distinguish these carapaces from that of the type of A. 

 beecheri. It is not improbable, however, that they belong to a 

 distinct species." 



5. Adocus lineolatus Cope. 



The status of this species has been considered, ante, p. 57. 



6. Basilemys variolosa (Cope). 



This has already been considered at length under its synonym 

 Basilemys ogmius, p. 57. 



DISCUSSION OF EVIDENCE REGARDING "JUDITH RIVER" TURTLES 

 AS BROUGHT OUT IN THE FOREGOING REVIEW. 



On combining the lists given by Hatcher and Hay it appears 

 that sixteen species of turtles have been accredited to the Judith 

 River formation. Of these sixteen species it has been demonstrated 

 that only three species have the type specimens from the original 

 Judith River area in Montana, while two additional species have 

 the types from the Belly River ( = Judith River?) of the Red Deer 

 River region of Alberta. The three species from Montana are the 

 following: 



Trionyx foveatus 



Basilemys imbricarius 



Polythorax missouriensis 

 The two Canadian species are: 



Baena antiqua 



Neurankylus eximius 



Of the remaining species four, as follows, have the types described 

 from Bijou Creek, Colorado, in beds supposed to be of Arapahoe 

 age: 



Trionyx vagans 



Plastomenus punctulatus 



Plastomenu sinsignis 



Adocus lineolatus 



