DISCOVERY OF NEW FOSSIL TAPIR IN OREGON 705 



The jaw. — The inferior border of the jaw is parallel with the 

 alveolar border. The symphysial portion rises at a low angle, 

 much less than in the tapir. The flatness of this angle is perhaps 

 due in part to a slight amount of crushing which the specimen 

 has sustained. The posterior border of the mental foramen is 

 directly below the anterior border of the second premolar. 



The fore limb. — The humerus and radius have about the 

 same shape as in the tapir. The deltoid ridge of the former is 

 broken off, so that it is impossible to say whether it was hooked 

 or not. The shaft of the radius is more strongly curved than 

 the corresponding element in Protapirus validtis as figured bv 

 Hatcher,' but a part of the curvature may be due to distortion. 

 The carpus does not call for special description, not differing 

 materially from that of Protapirus obliquidens . W. & E. The ante- 

 rior contact of the lunar and magnum is still small, as in the 

 White River species. There were four digits in the manus, the 

 length of metacarpals III, IV, and V being about the same as in 

 E. bairdii, but less robust. In shape they correspond closely with 

 the metacarpals of the latter, except that the proximal portion 

 of the fifth is inclined at a greater angle to the shaft of the bone 

 than in the living form. The phalanges, which are of the second 

 row, are shorter and less robust than those of the tapir. 



Pliylogenetic position. — The remains just described indicate an 

 animal much larger than any of the White River species of the 

 same genus. The structure of the molars and premolars suggests 

 Protapirus validiis as a probable ancestor. There are, however, 

 several differences. In addition to the considerable difference 

 in size, the third premolar oi P. robustus has the anterior cross 

 crest vertical to the long axis of the jaw, while in P. validiis it 

 is somewhat oblique. The diastema, as in P. validiis, is shorter 

 than in Elasniognathiis, while the mental foramen has moved 

 slightly posterior to the position it occupies in the White River 

 ancestor. Gradations between the two types probably occur 

 among the as yet unknown tapirs of the Lower and Middle John 

 Day. 



^Loc. cit., p. 167, Fig. I. 



