////: . I. \ 77. ///"A 1 LIMBS. 83 



i:.rh-f>uit'n'. The superior, the largest, presents: Above, an articular 

 surface adapted to tin; inferior metacarpal surface, aud consequently composed 

 of t\v -,'lenoid cavities separated by a groove running from front to back; 

 laterally, and a little posteriorly, a well-defined tubercle of insertion. Tho 

 int'i-i-ior r.i7/v/////y has a transversely elongated articular surface to cor- 

 rcspon.l to the second phalanx; this surface is formed by two condyles 

 si paiated by a middle groove, and surmounted laterally by a small 

 tulx-rosity for ligainentous insertions. The external coudylo is smaller 



49 



LATERAL VIKW OF TIIK DNilTAL 

 I l-ll'i. i IF RIGHT LIMtl. 



1. L-inje metacarpal bone; 2, 3, Outer 

 and inner sesaiin'i'U ; 4, First, proximal, 

 suffraginis or metacai ]ial phalanx ; 5, 

 Its posterior surface; fi, Tuberosity for 

 ligamentous insertion; 7, Inner coudyle 

 of ditto ; 8, Eminences on second pha- 

 lanx t'r attachment of lateral liga- 

 ment ; 9, Smooth surface for passage 

 of deep flexor tendon on second pha- 

 lanx; In, Imprint for the insertion of 

 tin- terminal branch "f the jx'rforatus 

 tt-ndou ; 11, Navifular bunt-; 1J, Third 

 phalanx, ]>filal, or cofiin bone ; 1 

 ba.silar process. 



POSTKRIOR V1K\V ] 



1. Lar^'i- metacarpal bone; '-', :!, Outer 

 and inner splint bones; 4, 5, Sesamoid 

 bones; b', SulVraginis ; 7, 8, Tub. 

 ties for insertion of crucial ligaments; 

 9, Triangular space for insertion of 

 short sesamoid ligament : li>. Anterior 

 of suflragiuis; 11, 12, Tuberositi. s 

 for ligamentory insertion; 13, Articu- 

 lar depression separating condyles ; 14, 

 IT-. Second phalanx ; 16, Scabrous bur- 

 face for ligamentous attachment; 17, 

 Smooth surface for gliding of deep 

 flexor tendon ; 18, Navicular bone ; 

 l:i. Tfilal bone; 'Jn, Basilar pr> 

 Jl, 1'lautar foramen. 



tliiin the internal, and when the bone is placed upon a horizontal piano, 

 tin- anterior face turned upwards, it only touches by three points the t\\ 

 tubercles of the upper extremity and the internal condylo ; by pressing ou 

 tlir i A ten i ;il condyle, it is easy to make the bone rock. 



Tlir first phalanx is a very compact bone, and is developed from two 

 pnints, one of which is for the superior extreinitv !i1<>n<-. 



a 2 



