980 THE WHITE KIVER FAUNA. 



molar is elongate anteroposteriorly, and has a very slight median constric- 

 tion, indicating traces of opposite grooves on the root. The alveolar border 

 is lost at the base of the third premolar, but from the remains of its alveoli 

 it was not much smaller than the fourth. The fourth premolar has lost its 

 cusp; it has a well-developed trenchant basal anterior lobe, not so large as 

 in the known species of Archcelurus and Nimravus. The base of the secto- 

 rial is absolutely and relatively shorter than in the specimens of D. felina 

 figured by Leidy. The portion anterior to the heel is equal in anteropos- 

 terior extent to the fourth premolar; it is longer in the specimens above 

 mentioned. The alveolus for the tubercular molar indicates a larger tooth 

 than that of the D. cyclops. 



The flange of the ramus is prominent, but short and rounded, extend- 

 ing but little below the symphysis, which itself is continued considerably 

 below the inferior anterior mental foramen. The superior anterior mental 

 foramen is below the middle of the symphysis. The anterior external 

 mental foramen is below the" anterior part of the alveolus of the first pre- 

 molar. The ramus is quite robust, and is convex on both faces below the 

 sectorial. The masseteric fossa is deep, but with sloping borders in front 

 and below. A gradual rise towards the coronoid process begins on the 

 inner side, at the posterior base of the sectorial. 



Measurements. 



11. 



Length of entire dental series 064 



Lengtli of molar deutal series 043 



Length of diastema 008 



Length of base of Pm. ii 005 



Length of base of Pm. iv .'013 



Length of base of .sectorial 017 



Height of anterior lobe of sectorial. T 010 



Long diameter of base of crown of inferior canine 009 



Depth of symphysis , 025 



Depth at flange 025 



Depth at front of sectorial 017 



Width of front of sectorial 007 



Width of front of symphysis 012 



The immature specimen is instructive in displaying the last two de- 

 ciduous molars, with more of the crown of the sectorial than is seen in the 

 other specimen. The latter shows the short trenchant heel, and the internal 

 tubercle, which is on the posterior edge of the middle lobe of the crown,. 



