OSTEOLOGY. /o 



posteriorly, terminating behind in a point wliicli extends 

 upwards. Its outer margin also anteriorly terminates in a 

 point. This surface articulates with the central part of the 

 inferior articulatorj surface of the radius, the vertical por- 

 tion of which corresponds to a continuation of this smooth 

 articulatory surface on to the inner surface of os lunare, 

 which surface, at its antero- superior part, also comes in ap- 

 position with OS scaphoides. This surface, too, is continued 

 on to the external part of the bone anteriorly, where it plays 

 on OS cuneif orme. The inferior surface presents two parts, 

 inner of which is convex anteriorly, concave posteriorly, 

 extending from the anterior to the posterior margin of the 

 bone. It articulates with os magnum, and anteriorly is. 

 continued on to the internal surface, forming a small 

 articulatory facet for os scaphoides. The outer portion of 

 the inferior surface is convex, anteriorly placed and comes 

 into connection with os unciforme. It is continuous with 

 the lower facet on the outer surface, on which os cunei- 

 forme plays. The anterior surface is slightly roughened^ 

 for attachment of connecting and the annular ligaments 

 The imsterior surface superiorly is concave, inferiorly pro- 

 minent ; it also gives attachment to the annular ligament. 

 The outer surface presents posteriorly, the outer surface of 

 this roughened prominence antero-superiorly, and antero- 

 inf eriorly are the articulatory facets for os cuneif orme. The 

 space between them is concave and rough for attachment 

 of interosseous ligaments. The inner surface superiorly along 

 its whole length presents the vertical articulation for the 

 radius, which anteriorly is continuous with a small surface 

 for OS scaphoides, which is also in contact with a corre- 

 sponding facet at the antero -mferior part continued from 

 the inferior surface. The space between these is rough for 

 attachment of interosseous ligaments. 



OS CTJNEIFORME is situated at the outer part of the 

 upper row. It articulates with radius, lunare, unciforme, 

 and trapezium. It presents two surfaces and four borders^- 

 The external surface is convex in every direction, and is- 

 roughened for attachment of the annular, connecting, and 

 outer lateral ligaments. Along its postero-superior margin it 

 presents a roughened groove for attachment of the capsular 

 ligament of its articulation with trapezium. The internal 

 surface presents anteriorly two smooth articulatory facets, 

 one superiorly continued as far as the anterior margin, con- 



