THE BONES OF THE LOWER LIMB 261 



anticus, the principal portion of which is inserted into an impression 



situated at the lower part of the groove. The external surface 

 presents, close to its superior and posterior borders, an L-shaped 

 facet for the middle cuneiform, at the anterior extremity of which 

 there is a small facet for the inner side of the base of the second 

 metatarsal. When the bone is held in its proper position, the L 

 is placed thus F in a right bone, and thus 1 in a left. The rest of 

 the surface is concave and rough for strong ligaments, except at the 

 lower and anterior part, where it gives insertion to a slip of the 

 tendon of the peroneus longus. The anterior surface is deep, and 

 presents a convex reniform facet for the first metatarsal, the concave 

 border being directed outwards. The posterior surface, much smaller 

 than the anterior, is characterized by a concave pyriform facet for 

 the navicular, the narrow end being upwards. 



Articulations. — Posteriorly with the navicular, anteriorly with the 

 first metatarsal, and externally with the middle cuneiform and 

 second metatarsal. 



Variety. — The internal cuneiform may be divided into two parts, dorsal and 



plantar. 



The middle cuneiform bone lies with the broad end of the wedge 

 upwards, and it supports the second, metatarsal. The dorsal 



Fig. 153. — The Right Middle Cuneiform Bone. 

 A, Internal View ; B, External View. 



surface is rough and nearly square. The -plantar surface, also rough, 

 is narrow, and give? insertion to a slip of the tendon of the tibiaJis 

 posticus. The internal surface presents, close to its superior and pos- 

 terior borders, an L-shaped facet for the internal cuneiform, placed 

 thus 1 for a right bone, and thus f for a left, the remainder of the 

 surface being rough and ligamentous. The external surface has a 

 vertical facet posteriorly for the external cuneiform, and elsewhere 

 it is rough and ligamentous. The anterior and posterior surfaces 

 are triangular and covered by cartilage, the former articulating with 

 , the second metatarsal, and the latter with the navicular. They 

 I are distinguished from each other in the following manner : the 

 i anterior surface is convex, whilst the posterior is concave; the 

 ; apex of the anterior surface is more pointed than that of the pos- 



