174 THE WASATCH AND BRIDGER FAUX.^. 



edge of the anterior face and extending externally. Its surface is entirely 

 smooth. The diastema is moderately long. The first premolar is a very 

 small tooth and has a single root. The crown is conic, and is pressed against 

 a narrow truncate face of the base of the anterior edge of the fourth (second) 

 premolar. 



Tiie vertical section of the fourth premolar is wedge-shaped, and the 

 profile of the crown is regularly and strongly convex. The anterior root 

 has a greater anteroposterior diameter than the posterior root, and the 

 enamel extends further downwards on it than on the posterior root, on the 

 external side; on the internal side this expansion is not so marked Tlie 

 enamel of the sides of the crown is thrown into parallel ridges, which are 

 gently curved, and which extend upwards and posteriorly to the edge, ex- 

 cept at the posterior border, where they fall a little short of the edge. When 

 they reach the edge the latter is angulate, forming a serrate outline. There 

 are twelve ridges from front to rear, and the anterior ones are closer together 

 than the posterior, the widths of the interspaces increasing in regular pro- 

 gression. The first true molar is very small, absolutely and relatively, its 

 length being one-third of that of the two premolars together. The outline 

 of the crown is elongate oval longitudinally placed. The median groove 

 is wide, and is open at both extremities. The lateral lobes have continuous 

 longitudinal acute edges, and number four on each side. The posterior lobe 

 is twice as long as any of the others on botli sides, and its edge is weakly 

 notched. No cingula. The alveolus of the anterior root of the second 

 molar indicates a rather wider tooth than the first molar. 



The anterior border of the masseteric fossa is a strong ridge, and passes 

 the alveolar border at the posterior edge of the first true molar. The fundus 

 of the internal pterygoid fossa is deeper or more external than the line of 

 the molars, falling below the external edge of the anterior masseteric ridge. 



Measurements. 



M. 



Length of ramns to last true molar inclusive (hJ05 



Diaiui-ters M. i 5 ""t'^roposterior 0040 



( f rnnsviirHC 0020 



1 aiitLTopostcrior 0085 



Diaiiietfr8 P-m. iv ? IraiisviTsc at l)ase 0030 



( vertical at middle 0045 



