^0.1.] COPE ON MIOCENE FAUN^ OF OKEGON. 61 



scendiiig to the niiddle of the length of the humerus, before abruptly 

 sinliing to the shaft. Its continuation is very prominent as it crosses 

 the axis of the shaft and becomes the anterior bounding ridge of the 

 internal side of the distal extremity. The section of the shaft is thus 

 subtriangular at all points, the obtuse apex of the triangles revolving 

 from the external side proximaUy, to the internal distally. The external 

 epicondyle is proximal to the condyle, as in Dicotyles, but is more prom- 

 inent than in that genus, and more as in Oreodon. It is the extremity 

 of the external acute edge of the humerus, which, rising from the shaft 

 at a point 90° posterior to the extremity of the deltoid ridge, turns for- 

 wards to the external epicondyle. The condyles are transverse and not 

 much contracted from side to side. The intertrochlear ridge is sharper 

 than in the species of Oreodon, Dicotyles, or Sus, and is continued round 

 to the shaft anteriorly, as in Bos. The condyles otherwise resemble those 

 of Dicotyles, not being so contracted in their tree margins as in Bos. 



Measurements of the Swnerus. 



M 

 Total lengtli q^-^q 



Lengtli from middle of head y'425 



Diameter of proximal eud [ ^i^teTO-posterior 0. 140 



(transverse 0.170 



Diameter of lieadi'"''**'''''"^''''*^"*''' '..--"-""!.".".'" ollOO 



' transverse q -^^qq 



Width of humerus near extremity of deltoid crest 0. 130 



Diameter of shaft just below extremitv of deltoid crest ^ antero-posterior 0.078 



< transverse 0.065 



Width at epicondyle , q y^n 



Transverse diameter of condyles 0.120 



c internally 0.070 



Antero-posterior diameter of condyles / at constriction 0. 055 



( externally 0.050 



This bone has about the size of the corresponding one of the EMno- 

 cerus Indicus. 



The carpal extremity of the ulno-radius is extended transversely. The 

 cuneiform or uhiar articular face forms posteriorly two-fifths the entire 

 extremity, and is only recurved in the external part of its posterior 

 border, which is very concave. The ridge Avhich separates it from the 

 hinar surface is very oblique, following just outside of the ulno-radial 

 suture, and contracting the cuneiform facet anteriorly. Distally and 

 posteriorly it forms the external border of the posteriorly reverted lunar 

 facet, bounding a deep fossa, which is posterior to the cuneiform facet 

 on its inner side. The lunar facet widens behind at the expense of the 

 scaphoid, so that the scapho-lunar ridge is even more oblique than the 

 luno-cimeiform. This ridge disappears supero-anteriorly, and the lunar 

 facet is recurved upwards, occupying the distal extremity of a. strong 

 median ridge of the ulno-radius. The reverted portion is almost a half 

 cij-cle in outhne, and is partly continuous with the scaphoid facet. The 



