434 PROFESSOR OWEN ON MACROPUS. 



the cuneiform, and supports part of the middle as well as the fourth and fifth 

 digits. 



The scapho-lunar (ib. fig. 10, s, I) presents to the radius (ib. 54) a convexity trans- 

 versely elongate, broadest ulnad, the breadth there being one third the length ; nar- 

 rowing radiad almost to a point (s) : the curve of the convexity is bold in both direc- 

 tions, but greatest across or in the short diameter of the surface. The major part 

 plainly answers to the convex radial articular surface of the lunar bone in Man and the 

 Orang ^ A non-articular surface, with ii-regular elevations and depressions on the 

 anconal (dorsal) surface of the bone, of a subtriangular form, exceeding in breadth that 

 of the radial convexity, intervenes between this and the two distal concave articular 

 surfaces for the trapezoides (ib. z) and magnum (ib. m) respectively ; whence the non- 

 articular tract is continued upon the radial extension of the bone, which terminates in 

 the convexity for the trapezium (ib. t), such articular surface being very small and 

 forming the apex of the scaphoid. This part of the scapho-lunar is similar to the 

 scaphoid in the Orang ^. Between the radial convexity and the magnal concavity 

 there is a narrow smooth tract adapted to the hinder and upper border of the unci- 

 form (u). Behind and below the ulnar end of the radial convexity is a slightly convex 

 siu'face for the cuneiform : in the front or anconal view of the carpus this articulation 

 is not seen. 



The cuneiform (ib. ib. c) is a comparatively small bone, with a concavity on its 

 proximal surface for the " styloid process " of the ulna (ib. 55), and a smaller and less 

 deep articular surface for the " head " of the pisiform (ib. jp). The distal surface of 

 the cuneiform presents a large undulate articular surface for the unciform; and its 

 backward extension just reaches the scapho-lunar. 



The pisiform (ib. ib. p) is clavate, articulated by a sort of condyle to the outer 

 proximal cup of the cuneiform ; it then loses thickness and gains breadth, and 

 expands to a broad sub truncate end. The bone projects backward and is twisted out 

 of place to show its form in figure 10. 



The trapezium (ib. t) is small, just touches the tips of the scapho-lunar, and ofi'ers a 

 small surface for part of the base of the broad metacarpal of the pollex (i.). 



The trapezium (ib. z) is still smaller, is wedged between the scaphoid (s) and 

 magnum (m), and offers a surface to the outer (radial) part of the proximal articular 

 surface of the second metacarpal (11.) 



The "magnum" (ib. m) is the next carpal of the distal row in point of size: it is 

 wedged between the scapho-lunar and unciform, and articulates with the ulnar half of 

 the proximal surface of the second metacarpal (11.), and with a larger portion of that of 

 the third metacarpal (iii.). 



The unciform, equalling in size the scapho-lunar, here occupies the position in the 

 wrist held by the unciform and intermedium^ in the Orang. It accordingly articulates 



' See 'Anat. of Vertebrates,' vol. ii. p. 541, fig. 361, b. ' Ib. ib. a. ' g & h ia fig. 361, op. eit. 



