944 THE JOHN DAY FAUNA. 



other without interruption. The second premolar is two-rooted, but the 

 roots are close together, and the anterior is the smaller. The long axis of 

 the tooth is oblique to that of the jaw, and the posterior root is within as 

 well as behind the anterior. The axis of the third premolar is very little 

 oblique. It is a robust tooth, and the crown is a little wider anteriorly than 

 posteriorly. The apex is subconical, and there is a posterior intermediate 

 tubercle whose section is wider than long. The heel is narrowed and not 

 recurved. There is no anterior tubercle or cingulum. 



The sectorial tooth is relatively of lai-ge size, its proportions being 

 those of the FeUdce and Hijoenidce. Its crown is broken in front, and where 

 not broken, is worn by use. It displays the peculiarity of a remarkably 

 short blade posterior to the lateral external notch ; and the base of the mid- 

 dle cusp of the crown is wide for a sectorial tooth, and was apf)arently sub- 

 conical when complete. It is also situated remarkably posteriorly, showing 

 either that the anterior sloping edge is long as in Arclicdurus dehilis, or that 

 there is an anterior basal lobe, as in the species of JElurodon (figs. 35, 36). 

 The internal lobe is altogether anterior, and, though worn off in the speci- 

 men, was probably small. The long axis of this tooth is that of the jaw. 



The tubercular or first and only true molar is as large a tooth as in 

 Canidce generally, but its external border is more oblique to the line of the 

 other alveoli. The posterior external cusp is well developed, though smaller 

 than the anterior; and the anterior external angle of the crown is so promi- 

 nent as to become worn by use like the true cusps. The latter are placed 

 well within the external base of the crown, which is prominent, but rounded, 

 not forming a distinct cingulum. The internal half of the crown is broken 

 away. The internal root comes so near the posterior edge of the maxillary 

 bone as to prove the non-existence of a second tubercular molar. The 

 enamel is smooth in all these teeth, and there ai'e no cingula. 



Measurements. 



M. 



Length of dental series from posterior edge of canine alveolus 058 



Length of base of Pm. ii 008 



Leugth of base of Pm. iii 013 



Width of base of Pm. iii _ 008 



Diameters of sectorial ^ '^"t«™P''«*«"''5 .- -O'^" 



( transverse m front 013 



External width of m. 1 (obliqne) 013 



Transverse width m. i, including internal root 021 



