774 THE WHITE EIVEE FAUNA. 



There are ten teeth in .10™ of the maxillary bone, and there are 

 twenty-four in the dentary bone. All are closely placed. Those of the 

 superior series are a little more robust ; their inner faces are convex, giving 

 the shaft a slight curve in profile. The apices of the teeth are not expanded, 

 but are wedge-shaped, with a cutting edge in the long axis of the jaw. A 

 strong bevel of the crown to the external maxillary face gives their apices 

 an especial robustness. Under the microscope their surface is delicately 

 parallel-wrinkled to the cutting edge. 



The scuta are parallelogrammic in form, and their proximal or con- 

 cealed portions are from one-fourth to one-third the entire length. The 

 granulation is like that of the cranium, fine and without distinct pattern. 



The centra of the vertebrae are moderately depressed, those of the dorsal 

 region the most so, and with the greater part of the face of the ball looking 

 upwards. These centra are not ridged on the middle line below, but are 

 slightly convex in transverse section. On either side, behind the inferior 

 extremity of the parapophysis, is an oj^en, shallow groove looking down- 

 wards, and defining the middle region as a wide band. Above, this groove 

 is bounded by an obtuse longitudinal ridge, and above the ridge occupying 

 the side of the centrum is a concavity. This is bounded above by the 

 prominent ridge that connects the zygapophyses. The transverse process 

 is vertical and narrow ; it is nearly sessile and is not subdivided. A verte- 

 bra inclosed in matrix close to the skull is probably from the anterior part 

 of the series. Its centrum is not so depressed as in those already described, 

 and it has a strong hypapophysial keel. Its ventral spine is rather elevated, 

 and is grooved posteriorly. 



As compared with the so-called Placosauridce of the Eocene foi-mation, 

 this species presents various points of resemblance, which the descriptions 

 of the former do not yet permit us fully to estimate. The presence of 

 regular cranial scuta will distinguish Peltosaurus from the known forms as 

 a genus. The granulation of the cranium and osseous scuta, is finer than in 

 any of the Eocene species I have met with. 



Measurements. 



M. 



Meilian width of parietals 0.0140 



Median width of frontals 0080 



