hatcher: oligocene canid^ 101 



lacerum posterium and medium and other foramina of this region are preserved, 

 though the outlines of some of them, owing to the absence of the auditory bullfe, 

 are not well shown. 



The Mandible.— The mandible (PL XV., Fig. 1, and PI. XVI., Fig. 3) has the 

 inferior border remarkably straight, much as in Daphoenus hartsJwrnianus. The hori- 

 zontal ramus retains the same depth throughout its entire length. The masseteric 

 fossa is deep. The angular process is pronounced, the extremity is broken away in 

 both rami, but it was apparently pointed and inclined upward and backward. The 

 postero-external border rises almost perpendicularly from the base of the angular 

 process to the condyle instead of inclining strongly backward as in Daphoenus. 

 There are two mental foramina, of which the anterior lies directly beneath P.x, and 

 the posterior beneath the middle of P.^. The position of both is midway between 

 the alveolar and inferior borders. The symphysial area is small and the union was 

 cartilaginous. The inferior dental foramen is situated rather low, near the inferior 

 border of the ramus, and well back toward the base. of the condyle. The coronoid 

 process is injured, but enough is preserved to show that it was high and broad, 

 and rose abruptly from the horizontal ramus at an angle of about 90 degrees. 



The Dentition. 



Superior Dentition. — Plate XV., Fig. 3. In the structure and arrangement of 

 the teeth the present genus more nearly resembles those conditions which obtain in 

 Temnocyon coryphseus, as described and figured by Cope (see Tertiary Vertebrata, 

 p. 896, PL LXXL), than any other species of dog known to the present writer. 

 The alignment of the incisors is more oblique and not so nearly at right angles to 

 the longer axis of the skull as in Daphoenus. This character is not so well shown 

 in the figures as it might be. Incisors - ^ - are very small, subequal and much com- 

 pressed. The position of I. ^ is but little posterior to that of I. -. Compared with 

 1 & 2 J 3. jg ygj-y large with its posterior border placed far behind that of I. \ 

 Neither of these characters is sufficiently emphasized in Fig. 3, PL XV. 



The canines are blunt through wear, stout and considerably compressed, but 

 without anterior or posterior cutting edges. 



Premolars -, -, - are stout and well developed and separated from one another 

 and the canine by short diastemata, while P. ^ is nearly in contact with P. ^. P. - 

 is fixed by a single root and consists of a simple cone directed obliquely forward and 

 downward. Premolars ^ ^ ^ are supported by two roots, the heel of the former is not 

 expanded transversely, but that of the latter is much expanded. The crowns of both 

 these teeth consist of a single median cone without anterior or posterior tubercles. 



