430 Douglass — New Species of Merycochoerus in Montana. 



zontal wedge-shaped forward projection of the narial opening, 

 and by the conical shape — as seen from the front — of the 

 large convexities in the region of the canines. These con- 

 vexities have their bases close together in the middle of 

 the incisive alveolar border, make a broad lateral sweep and 

 die out on the face in front of the anterior projection of the 

 malo-maxillary ridge. The first mentioned ridges die out on the 

 anterior inner sides of these convexities a little distance above 

 the alveolar border. 



The anterior part of the narial opening begins anteriorly in 

 a rather blunt point, widens gradually as it extends backward 

 and slightly upward for a distance of 3 cm , then the sides are 

 nearly parallel and horizontal about the same distance, then it 

 expands and ascends to form the inferior part of the posterior 

 oval opening. This posterior part of the external nares looks 

 forward and slightly upward, thus forming a high angle with 

 the anterior part. Above it is arched over by the short back- 

 ward sloping nasals. Its lower border is in advance of the 

 orbits, but in front of the bases of the nasals a notch extends 

 back of the orbital border. The vertical height is about 5 cm . 

 Between the narial opening and the orbit the tongue of the 

 maxillary curves upward and then backward, apparently end- 

 ing in a wedge-shaped process between the nasals and the 

 frontals in a plane with the posterior parts of the orbits. The 

 suture separating the frontal and maxillary extends from this 

 point outward and forward and then downward, passing close 

 to the anterior border of the orbit. The skull is a little 

 injured just at the border of the orbit and the orbit is still 

 filled with the matrix so that the lachrymal bone cannot be 

 made out, but it occupies an extremely small space if any in 

 front of the orbit. The malo-maxillary suture continues 

 downward from the orbital border to a line 2'2 cm lower than 

 the lower border of the orbit, where it curves forward and 

 downward to near the lower anterior border of the overhang- 

 ing malo-maxillary ridge. From this place it cannot be traced. 

 The suture where seen is well defined, is complex but forms 

 a quite regular band 3 to 4 mm broad. On the roof of the 

 mouth the maxillo-palatine suture appears near the root of the 

 second molar, extends forward and slightly inward to opposite 

 the posterior lobe of ml, then transversely across the palate in 

 nearly a straight line. The roof of the mouth is broad and 

 concave. The incisive foramina are confluent, but this is appar- 

 ently due to the breaking away of the thin median partition, 

 part of the superior portion of which still remains. It now 

 appears as an oval opening, the smaller end being directed 

 backward. Its length is 3 cm , and its greatest width l # 5 0m . 



