and marginal bones of very small individuals. These bones are, hoW- 

 ever, not only thoroughly ossified, but are very stout, indicating the adult 

 age of the animal. The deeply impressed scutal sutures and heavy pro- 

 portions, as well as the elevated carnia of the carapace, indicate affinity 

 with Cistudo, or perhaps, Testudo, as another generic character, it may be 

 noted that the vertebral bones are subquadrate, and support the neural 

 canal without intervening lamina. 



The carina of the carapace is abruptly interrupted occasionally ; some- 

 times with, sometimes without, a pair of pits, one on each side. Trfe 

 marginal bones are well recurved, and the scutal sutures are deeply im- 

 pressed on them. M. 



Length of vertebral bone 009 



Width " " 0085 



Length marginal " 01 



This is least of the tortoises of the Bridger Formation. 



Pal^otheca terrestris. Cope. 

 Represented by three individuals, one of which may be regarded as the 

 type. They are all thinner than the P. polycypha, and larger, being 

 about equal to the Aromeclielys odoratas of our ponds. 



In the type specimen the carina of the vertebral bones is interrupted 

 by a deep sutural groove, which is less pit-like than in P. polycypha, 

 The bone itself is broader than long, being, perhaps, from the hinder 

 part of the carapace. The clavicular (episternal) bone is preserved. It 

 is characterized by the considerable and abrupt projection of that part 

 enclosed by the gular scutum, which resembles what is sometimes seen 

 in Testudo. The edge of this part is entire and acute. The posterior 

 part of the projection forms a step-like prominence behind, on the supe- 

 rior or inner face. The bone is almost as wide as long, and the meso- 

 sternal causes a very slight median truncation, but overlapped much on 

 the inner side. The gular dermal suture does not reach it. M. 



Length vertebral bone 009 



Width " " 018 



Length episternal 02 



Width " (transverse to axis of body) • 017 



Width of the costal 011 



Thickness proximally 003 



In the second specimen, a strong groove is seen to bound the lip of the 

 front lobe of the plastron as in the species of Notomorpha. In it the 

 marginal is seen to be stout, a little recurved, and sharp-edged. A ver- 

 tebral differs from those described in being longer than wide. 



In the third individual the gular lip is not so prominent as in the type, 

 and the mesosternal bone truncates the clavicular extensively, giving it 

 thus a more elongate form. The gular scuta expands to its front margin. 

 Tiie marginal bone is stout and sharp edged, and is not so deeply im- 

 pressed by the dermal suture, as in P. polycypha. 



Length episternal 016 



Width " 026 



