MR. ST. G. MIVART ON THE SKELETON OF THE PRIMATES. 189 
unites with the distal concavity of the scaphoides by a transverse articular surface, more 
or less interrupted towards its middle by a rough non-articular part. 
The margin which separates the first and third of these surfaces has its middle portion 
produced into a more or less pointed process, projecting, proximad, over the groove which 
divides the bone from the scaphoides (Pl. XLII. fig. 5 e). 
The radial end of the intermedium is obtusely pointed (Pl. XLII. figs. 5 & 6, d), but 
its ulnar end is truncated (Pl. XLII. figs. 5 & 6,c) and presents a small articular surface, 
more or less concave, which joins the semilunare. The angle at the junction of the distal 
end of this small surface with the ulnar end of the border separating the first and second 
of the before described surfaces, projects somewhat over the radial border of the dorsum 
of the os magnum. 
Semilunare. (Plate XLII. figs. 7-9.) 
This is very large in the Orang, and much larger, as compared with the scaphoides, 
than in either Man or Troglodytes. It is of about the same size as the semilunare of 
the Gorilla, and has very nearly the same shape. As compared with that of Man it is 
especially elongated from above downwards, and its proximal surface is more strongly 
convex from behind forwards, 7. ¢. from dorsum to palm. 
The surface for the cuneiforme (Pl. XLII. fig. 8 ¢) differs from the same surface in Man 
and Troglodytes, in that it is decidedly concave. The dorsum of the bone is narrower 
transversely than in Man or the Gorilla; and the concave surface for the magnum passes 
insensibly into that for the cuneiforme, though between the two is a very small part which 
joins the unciforme. 
Cuneiforme. (Plate XLII. figs. 10 & 11.) 
This bone is much elongated as compared with its homologue in Man and T'roglodytes. 
It is of about the same size as the intermedium, and, as has been before said, it is of 
somewhat similar shape. It is, however, extended rather from above downwards than 
transversely, and its large articular surface is concavo-convex, instead of concave only, 
as in the intermedium. 
It differs from the cuneiforme of both Man and Troglodytes in the convexity of the 
surface for the semilunare, and in the distance between the facet for the pisiforme and 
the proximal end of the bone. 
The rough portion for ligaments of the anterior surface is continued as a wide and 
roughened groove (Pl. XLII. fig. 11 ¢), separating the articular surfaces for the unci- 
forme and pisiforme. That for the last-named bone is smaller, absolutely as well as 
relatively, than in any of the higher forms. The smooth surface for the fibro-cartilage 
of the wrist joint (Pl. XLII. fig. 10 ¢) is more elongated than in Man or Troglodytes ; 
but, as in the latter genus’, the tubercle for the internal lateral ligament of the wrist is 
' Trans. Zool. Soc, vol. vy. p. 10. 
