412 



FOSSIL TURTLES OF NORTH AMERICA. 



do not display raised margins. Hie anal marginal bone is wedge-shaped, with the posterior margin 

 representing a truncate apex. Its surface and margin are convex, and the anterior sutural margin is 

 concave. 



A fragment, which is in all probability the posterior lobe of the plastron, is characteristic. It is 

 thick, and its inferior face is somewhat recurved posteriorly. The outline of the margin presents a pro- 

 nounced obtuse angle, and the edge is several times abruptly notched. 



Measurements of No. i. 



Diameter of half of lip : 



At base 



Vertical 0.040 



Transverse 043 



Length outer edge 056 



Diameter second marginal from anal : 



Thickness .oig 



Width .030 



Length free margin of anal .026 



Width of anal above 050 



Thickness of a vertebral bone 01 1 



Thickness of a costal at middle 009 



found by myself near the head of Horse Tail Creek, in northeastern Colorado. 



Cope has explained his fig. I as that of the right half of the lip seen from above. This may 

 be correct, but it is probable that it presents the left half of the lip seen from below. 



534- 



FlGS. 534 AND 535. Testudo peragrans. Skull of type. Xl. 



534. Upper surface. 535. Lower surface. 



Testudo 



peragr 



Testudo peragrans Hay. 

 F 'g s - 534-53 8 - 

 Hay, Ann. Carnegie Mus., iv, 1906 (1907), 



rigs 



The type and at present only known specimen of this species is No. iioi of Carnegie 

 Museum, Pittsburg, Pennsylvania. It was collected by Mr. Earl Douglass, in 1903, south of 

 McCarty's Mountain and Big Hole River and north of Dillon, Montana. There is at present 

 some uncertainty regarding the age of the deposits. They may be either Oligocene or Lower 

 Miocene. 



The specimen furnishes the damaged carapace and plastron and a nearly complete skull. 



The skull (Hgs. 534-536) lacks a part of the palatal region, the occipital condyle, and the 

 right otic region. I he lower jaw is so closely cemented in its place that it is thought best not to 

 attempt to remove it. We are therefore unable to determine the arrangement of the ridges and 

 grooves of the masticatory surfaces. There are, however, no reasons for believing that the 

 species does not belong to the genus Testudo. 



