ME. ST. G. MIVAET OX THE SKELETON OP 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 (PI. XLII. fig. 5 e). 



The radial end of the intennedium is obtusely pointed (PI. XLII. figs. 5 & 6, d), but 

 its ulnar end is truncated (PI. 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 downwai'ds, and its proximal surface is more strongly 

 convex from behind forwards, i. e. from dorsum to palm. 



The surface for the cuneiforme (PI. XLII. fig. 8 c) 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 Troglodytes. 

 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 cuneifonne 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 (PI. XLII. fig. 11 c), separating the articular "surfaces for the unci- 

 forme and pisiforme. That for the last-named bone is smaller, absoUitely as well as 

 relatively, than in any of the higher forms. The smooth surface for the fibro-cartilage 

 of the wrist joint (PI. XLII. fig. 10 e) 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. vul. v. p. 10. 



