THK FORE-I.IMH. 4."> 



the palmar aspect of the bone is a ridge running from before back- 

 wards. Mertens names this bone os lunatv.ru. 



3. Os naviculare (Fig. 39 ;/), Duges, n. 39. The third bone 

 <>t' the first row does not articulate with the bones of the forearm. 

 It is connected with the os lunatum by a saddle-shaped surface, pos- 

 teriorly with the os capitation by means of a concave surface. On 

 the inner surface is a small concave articular facet for the os mulf- 

 angufii.m ini/ius or traptzo'uJcs (Fig. 39 t'). The convex palmar 

 surface of the bone articulates with the os mult anyul urn majv.s (/) ; the 

 radial side is non-articular, and with the os lunatum forms a rid-e 



O 



directed forwards. Mertens names this bone 09 triquetrum. It is 

 evident, however, that if the arrangement in man obtains as a 

 standard, the nomenclature of Duges, which I have here used, is 

 correct; but the os navirulare is no longer in contact with the 

 articular surface of the os antHracJiii. 



The second or distal row also consists of three bones : 



4. Os eapitato-lt>- Fig. 39 Jtc), Duges, n. 40, 41, 42. 

 corresponds with the os capitatum and Jiamatirn) 1 J which are here 

 fused together. It is the largest bone, and articulates with all three 

 bones of the first row; it is crescentic, with the concavity directed 

 posteriorly, and on the convex surface has three facets for the three 

 outer ossa metacarpi. 



5. Os mnltaitffvbi.il> minus, s. trapezoidex (Fig. 39 /'), Duges, 

 n. 43, is a small bone lying next to the foregoing; it artieuhr 

 with the os inetar:arpl II, and anteriorly with the r> nariculare. 

 Duges considers it to be the os trapezium. 



6. Os mv.ltanijui- . trapezium (Fig. 39 /), is a small 

 bone, which is placed on the convex palmar auricular side of the 



"hire. Duges regards this bone as os metacarpi poll 

 (Duges, n. 44), Mertens as multangulum miniix. It appears to me 

 that the interpretation here given is justified, because it articulates 

 with the rudiment of the thumb, and as it possesses no resemblance 

 to a long bone it cannot be regarded as an os met a far pi. 



Structure of the carpal bones. All the carpal bones consist 

 of calcified cartilage, though variations due to age occur in tlie 

 amount of the deposit. 



Wrist joint. As stated above, the os lunatum and ozpyramidale are 

 articulated with the forearm. In addition to the capsules unitino- 



1 



the parts, there are strengthening ligaments, two of which require 

 special mention. One of these arises from the palmar surface of 



1 Duges thinks that o* is also included. 



