1881.1 ^"y [Cope. 



Measurements of Fore Limb. M. 



Length of lunar 010 



Depth " Oil 



Length of magnum 005 



Depth •' 017 



Length unciform 009 



Width " 009 



Depth " (total) 014 



" " of inferior facets , . .007 



Length of third metacarpal 068 



Proximal diameter third metacarpal i anteroposterior. .. .008 



' transverse 008 



Length of fifth metacarpal 012 



" median series of phalanges 027 



" first median phalange 010 



Width of do. proximally 008 



Length of second phalange 006 



{proximally 0070 

 medially 0055 

 greatest 007 



The body of this animal was about the size of that of a red fox. The 

 legs were more slender or elevated, and the head of course was shorter and 

 thick. 



The unique specimen on which our knowledge of this species rests was 

 cut from a block of calcareous sandstone of the bed of the Washakie basin 

 of the Bridger Epoch, near South Bitter creek, Wyoming Territory. The 

 bones are generally in the relation of the position in which the animal died. 

 The neck is depressed and the left fore leg raised so as to be in contact 

 with it, and the head is raised so as to clear the left wrist. 



Triplopus amarorum Cope. 



The characters of the fore-foot of this species being unknown, it is not 

 possible to determine its generic position. It has, however, one of the 

 well-marked characteristics of the genus Triplopus, in the osseous enclo- 

 sure of the meatus auditorius externus, through the ossification of the ex- 

 ternal prolongation of the otic bulla, and tympanic cartilage. I cannot 

 therefore refer it to Eyrachyus. 



It is represented by a skull from which a large part of both maxillary 

 bones and the mandible have been lost, and which is accompanied by parts 

 of the ulna and radius, parts of the ilium, a femur, and tibia, and nearly 

 all of the posterior foot of the right side. The posterior parts of both max- 

 illary bones remain, and they support each, the last superior molar tooth 

 from which the external wall has been broken away. The portions of 

 molars remaining exhibit characters which lead me to suspect that the 



