120 



it is gently convex and situated towards the lower half of the fibular part of the 

 anterior surface. The inner cuneiform surface is about ten lines by seven lines 

 in extent, situated, with its long axis transversely, close to the inner margin of 

 the bone, nearer the lower than the upper margin, and separated by an uneven 

 non-articular tract of two lines in breadth from the outer cuneiform surface. 



The OS cuhoides* has the form rather of a thick and short wedge, the base 

 of which is formed by the rough flat subquadrate surface, which appears at 

 the upper and outer part of the tarsus : the outer and anterior margin of 

 this surface is developed into a rough eminence. On the outer side of the 

 cuhoides there is a slightly convex surface for the calcaneum ; the whole of the 

 back part is excavated to receive the astragalar convexity : a narrow vertical 

 strip of articular surface on the inner surface joins the naviculare, and these 

 three facets are continuous with each other. At the fore and upper part of the 

 inner side of the cuboides there is a small surface which touches the base of the 

 third metatarsal ; this is separated from the navicular strip by a rough depres- 

 sion, bounding the interspace between the cuboid and adjoining cuneiform 

 bone : the anterior surface of the cuboides supports a very large articulation 

 divided by a vertical narrow groove into two parts, for the two outer metatarsal 

 bones. The under part of the cuboides is excavated by a rough depression, 

 bounded anteriorly by a rugged protuberance. Although the cuboides articu- 

 lates with six distinct bones, it has only two distinct smobth articular tracts ; 

 that for the middle metatarsal being continuous with the large outer metatarsal 

 surfaces. 



A vacant interspace in the skeleton divides the cuboid from the external cunei- 

 form bonef, which has the usual triangular form, with the base shorter than the 

 sides. This bone presents only two articular surfaces, a posterior one, slightly 

 concave, for the naviculare, and an anterior one, in a less degree convex, for 

 the oblique base of the middle metatarsal ; the outer angle of the anterior sur- 

 face is more produced than that of the posterior surface. The external cunei- 

 form diminishes in antero-posterior thickness from the base towards the apex, 

 which is rounded off". The three margins of the bone are flat or shghtly convex, 

 rough, and perforated by vessels : there is no trace of an articular surface for the 

 cuboides on the outer margin, or for a middle cuneiform bone on the inner one. 

 * Plates XXI. and XXII. d. f Ibid. e. 



