143 



They exhibit Ihe usual ('onus, Ihc first l)ciiig oblong with the borders convex 

 outwardly, the others to tiie lifth being wide coffin-shaped, and the remaining 

 ones are more regularly hexagonal. 



The second and third vertebral scute-spaces are quadrate with the lateral 

 defining-grooves strongly double sigmoid. The second space is Ijroader than 

 long, but the third is the reverse. 



4. It was the nearly complete shell, represented in Plate X, which was 

 attributed to a different species from the former specimens, under the name 

 of Emys Jeanesi. This fine fossil was obtained near Fort Bridger, Wyoming, 

 during Professor Hayden's exploration of 1870. It is considerably distorted 

 from pressure, the right side being crushed inwardly so as to be nearly ver- 

 tical. The shell, completely petrified like all its associate fossils, is filled 

 with a greenish-gray sandstone. Its prominence or convexity in the original 

 condition was perhaps not greater than in some of the ordinary living emydes, 

 but it is apparently more prominent, from the lateral pressure to which the 

 shell has been subjected. 



The carapace is oval in outline with the l>orders moderately deflected, 

 acute, and without conspicuous indentations, except that it is slightly notched 

 in the position of the nuchal plate. The plastron has the same form and 

 degree of development in relation with the carapace as in living species of 

 the genus. It is truncated in front, and notched behind. 



Although the sutures of the shell are conspicuously visililc, the bones or 

 ])lates are all closely united, and the specimen appears to have been nearly or 

 quite in theadult condition. No lines of successive growth are visible on the 

 plates, which are everywhere smooth. The position or boundaries of the 

 scutes are indicated by deeply marked grooves. 



Ten vertebral plates appear to constitute the series, the connection of the 

 last two in the specimen being destroyed. In form and proportians they bear 

 a near likeness to those in ' emydes in general. They are rather wider pro- 

 portionately than those in the specimen first referred to E. Stevemonianm, 

 Init otherwise are sufficiently alike to pertain to the same species. 



As usual, the first vertebral plate is longest; then follows the third. The 

 second, fourth, and tilth are nearly equal. The others, to the eighth, succes- 

 sively diminish. The second vertebral plate is as wide at its fore part as it 

 is long, but the succeeding two plates are considerably longer than wide. 



