36 



indicate large vertical ridges joining the parietals, and heavy 

 pterygoid processes, perforated at the base by the alisphe- 

 noid canal. They are again perforated by the foramen ovale 

 three fourths of an inch behind this. This completes the 

 base of the skull. 



The parietals are very large, they form nearly the whole 

 of the temporal fossae ; which, deep and wide, enclosing a 

 small cranial cavity, contrast strongly with the long and 

 shallow temporal fossae of the tapir. The parietal crest is 

 very broad, and grooved at the top. This high crest and 

 deep adjacent temporal fossae we at first mistook as pointing 

 to an exclusively carnivorous type. The forehead has a tri- 

 angular appearance, from the divergence of the two side 

 ridges of the sagittal crest. The postorbital processes are 

 very large, but do not reach the opposing processes of the 

 malar. The orbit is thus left incomplete posteriorly, while in 

 form it greatly resembles that of the Sus. The squamosal 

 encroaches considerably upon the temporal ; and sends out- 

 wards and downwards a great zygomatic process, which 

 arches outwards from the skull as in the Felida, and is more 

 powerful than in any living carnivore (Leidy.) A strong 

 downward direction is especially characteristic, the whole 

 describing a sigmoid curve. The mastoids are of great size 

 vertically, and transversely they are confluent with the par- 

 occipitals. A low, thick process on the internal side of the 

 glenoid cavity prevents lateral motion. 



The nasals are long, broad, and thick, convex from side to 

 side, narrowing slightly anteriorly. They are straight, as in 

 Sus y which they resemble more than they do either tapir 

 or rhinoceros. The anterior borders are rounded, and do 

 not reach as far forward as the symphysis of the premaxil- 

 lary. The malar is broad and thick, probably forming but 

 little of the face, being directed downwards and backwards 

 to meet the zygoma. The postorbital process is short, and 

 rather larger than Dr. Leidy has indicated. The maxillaries, 

 smaller proportionately than in Sus, form posteriorly the 

 floor of the orbit ; while the infraorbital foramen is situated 

 over the last premolar. The premaxillaries fail to reach the 

 nasals. 



