PANTODONTA. 
195 
the smaller of the two parts, and gives the antero-posterior as the greatest 
dimension. Viewed from the front, four articular facets are visible, one 
superior for the radius, one external for the lunar, and two inferior for the 
trapezoides and trapezium. The radial surface is the largest, but is smaller 
than those of the trapezium and trapezoides together; it is decurved ante¬ 
riorly, leaving but a narrow external front surface, which is continued 
without widening along the ^ entire internal (free) side. The lunar and 
trapezoid facets unite in front at an acute angle, but behind this angle they 
separate, leaving a triangular facet for the magnum. The facets for the 
trapezium and trapezoides are subequal, and related by an open angle. 
I fail to make an exact fit between these facets and the proximal ends of 
the two bones in question, which give three instead of two facets. I have 
therefore thought that a small bone present at this point in one of the 
unseparated carpi might be an os intermedium. My desire to retain the 
bones of this carpus in the relation in which I found them prevents me 
from settling this point. The small size of the bone in question is appro¬ 
priate to the small interval unfilled by the scaphoid. The scaphoid is the 
smallest of the carpals of the proximal row, and presents the smallest facet 
for the bones of the forearm. 
The lunar is a robust bone, its antero-posterior diameter somewhat 
greater than the transverse. Viewed from above, its form is that of a 
spherical equilateral triangle with rounded angles. Its anterior two-thirds 
above are occupied by the convex facet for the fore leg; its lower surface 
presents four longitudinal facets; the two lateral for the scaphoid and cunei¬ 
form subvertical. The median two apply to the unciform and magnum 
respectively. The anterior face is longer (longitudinally) than that of the 
scaphoid.- The cuneiform is subtriangular and flat, and with a greater 
length than any other carpal (except the unciform), directed outward and 
backward. Having this oblique position, only a part of one of its long 
sides is presented anteriorly, and the articular face of the ulna extends 
obliquely across it. Behind the latter, the surface is beveled, forming a long 
subtransverse facet for the pisiform. The inferior face is convex obliquely, 
the convexity extending from the inner anterior to the external posterior 
angle. The distal end is narrowed and truncated, with a thick convex 
