THE ANTERIOR LIMBS. 83 



Extremities. The superior, the largest, presents: Above, an articular 

 surface adapted to the inferior metacarpal surface, and consequently composed 

 of two glenoid cavities separated by a groove running from front to back ; 

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

 inferior extremity has a transversely elongated articular surface to cor- 

 respond to the second phalanx; this surface is formed by two condyles 

 separated by a middle groove, and surmounted laterally by a small 

 tuberosity for ligamentous insertions. The external condyle is smaller 



Fig. 48. Fig. 49. 



LATERAL VIEW OF THE DIGITAL 

 REGION , OUTSIDE OF RIGHT LIMB. 



1, Large metacarpal bone; 2, 3, Outer 

 and inner sesamoids ; 4, First, proximal, 

 suffraginis or metacarpal phalanx, 5, 

 Its posterior surface ; 6, Tuberosity for 

 ligamentous insertion ; 7, Inner condyle 

 of ditto ; 8, Eminences on second pha- 

 lanx for attachment of lateral liga- 

 ment; 9, Smooth surface for passage 

 of deep flexor tendon on second pha- 

 lanx ; 10, Imprint for the insertion of 

 the terminal branch of the perforatus 

 tendon; 11, Navicular bone; 12, Third 

 phalanx, pedal, or coffin bone ; 13, Its 

 basilar process. 



POSTERIOR VIEW OF FRONT DIGITAL 

 REGION. 



1, Large metacarpal bone ; 2, 3, Outer 

 and inner splint bones ; 4, 5, Sesamoid 

 bones ;'6, Snffraginis ; 7, 8, Tuberosi- 

 ties for insertion of crucial ligaments ; 

 9, Triangular space for insertion of 

 short sesamoid ligament ; 10, Anterior 

 face of suffraginis ; 11, 12, Tuberosities 

 for ligamentory insertion ; 13, Articu- 

 lar depression separating condyles ; 14, 

 15, Second phalanx ; 16, Scabrous sur- 

 face for ligamentous attachment; 17, 

 Smooth surface for gliding of deep 

 flexor tendon; 18, Navicular bone; 

 19, Pedal bone; 20, Basilar process; 

 21, Plantar foramen. 



than the internal, and when the bone is placed upon a horizontal plane, 

 the anterior face turned upwards, it only touches by three points the two 

 tubercles of the upper extremity and the internal condyle ; by pressing on 

 the external condyle, it is easy to make the bone rock. 



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

 points, one of which is for the superior extremity alone. 



