A NEW FOSSIL PACHYDERM. 269 



the internal concave surface, at the base of the olecranon, is a nar- 

 row groove, with a depression behind the interior ridge. The low- 

 er extremity is dilated, so that the internal edge of the shaft is 

 rendered concave ; anteriorly this extremity is convex, posteriorly 

 flat ; the styloid process (a) is short, and immediately above it is a 

 slight concavity. The lower articular surfaces are shown in fig. 

 22, a being the styloid process. The other faces for the scaphoid, 

 semilunar and cuneiform, are so well defined as scarcely to need 

 description ; and the more so, because, from the meagreness of our 

 museums, I have not been able to make comparison with the cor- 

 responding parts of other Unguluta. There is very little resem- 

 blance between the present specimen and the antebrachium of a 

 hog ; the resemblance to a horse is much more decided, but the 

 lower articular surfaces are quite different in form. 



Os calcis. — The bone of the left side was found with both ex- 

 tremities fractured ; the shaft flattened, with rounded edges : the 

 inferior margin (concave in Sus) is perfectly straight ; the superior 

 is scarcely concave ; the large process for articulation, with the 

 astragalus, is much thickened inferiorly, and marked with a slight 

 groove. The articular surface is scarcely longer than wide, slightly 

 concave ; superiorly it is scarcely prominent beyond the margin of 

 the shaft : the hollow below this process is regularly narrowed, but 

 there is no fossa superiorly between the articular face and the an- 

 terior part of the bone. In the common hog there is a very distinct 

 fossa. 



Os cuboides. — The bone of the left side is shown in fig. 25, ex- 

 ternal view ; and fig. 26, internal view. The surface for the calca- 

 neum is long and sinuous, as in Sus, but the depression (a) is much 

 deeper ; between this surface and that for the astragalus is (b) 

 a deep groove, rounded at the extremity, extending almost to the 

 concavity (a). The astragalian surface is deeply concave, and 



