140 



Lines. 

 Length of seventh vertebral plate ] :>, 



Breadth of seventh vertebral plate. 28 



Length of eighth vertebral plate. . . : 13 



Breadth of eighth vertebral plate U4 



The costal capitula of Testudo Corsoni appear in the specimens as robust 

 conical eminences, with a broad, expanding base, and are proportionately 

 better developed than in living species of Testudo, and even many of the 

 species of Emys. 



Figs. 2, 3, Plate XXIX, represent the upper extremity of a humerus, and Fig. 

 4 the lower extremity of a femur, which were found in association with the 

 fragment of a carapace last described, and may reasonably be supposed to per- 

 tain to the same animal. Both fragments resemble the corresponding parts 

 of a modem Testudo. 



The head of the humerus has an inner trochlear extension, as in recent 

 species of Testudo. Independent of this process, the transverse diameter of 

 the head is nearly as great as the fore and aft diameter. In the specimen it 

 presents a discoidal, flat surface, but this is evidently accidental. 



The measurements of the specimens are as follows : 



Lines. 



Breadth of humerus between tuberosities , 29 



Breadth between outer tuberosity and inner extension of the head 32 



Breadth of the head with its inner trochlea . 20 



Fore and aft diameter of the head 17 



Breadth of the distal end of the femur 24 



EMYS. 



Emys wyomlngensis. 



Of the many remains of turtles from the Bridger Tertiary deposits I have 

 had an opportunity of examining, most of them appear to me to belong to a 

 species of Emys, which presents so much variation in anatomical details that 

 the first specimens brought to my notice were viewed as pertaining to no less 

 than four distinct species. These were named Emys icy omin gen-sis, E. Steven- 

 sonianus, E. Jeanesi, and E. Haydeni. A subsequent examination of ad- 

 ditional specimens, collected by Dr. J .Van A. Carter and Dr. Joseph K. Cor- 

 son, United States Army, and presented by them to the Academy of Natural 

 Sciences of Philadelphia, has led me to regard all those indicated under the 

 above names as really pertaining to a single species. I admit that I may be 

 wrong in this determination, but if such is the case, it would appear that 

 almost every specimen presents characters to distinguish a species. 



