METATARSUS. 47 



dilates with the scaphoid ; interjially, it articulates with the internal 

 cuneiform, and externally, with the external cuneiform bone. 



External CaneiformJ — Intermediate in size between the two 

 last. It is wedge-shaped and base upwards. Anteriorly it articu- - 

 lates with the third metatarsal bone ; ijosteriorly there is a quadran- 

 gular facet for the scaphoid ; internally it has two articular surfaces, 

 the posterior of which is the larger, and for the internal cuneiform 

 bone ; the anterior is for the second metatarsal. Externally is an 

 angular projection, in front of which is a small facet for the front 

 metatarsal bone, and behind which is an articular surface for the 

 cuboid bone. 



Cuboid.^ — Placed at the outer portion of the foot, is somewhat 

 cuboidal in shape ; superiorly, it is rough and convex ; irtferiorly, is 

 a prominent ridge for the calcaneo-cuboid ligament, and in front of 

 this ridge is a groove, commencing at the external edge, and running 

 obliquely forward, in which plays the tendon of the peroneus longus ; 

 internally, it articulates with the external cuneiform ; anteriorly, 

 with the fourth and fifth metatarsal bones ; posteriorly, is a semi- 

 spiral surface for the greater apophysis of the os calcis. 



METATARSUS, 



Consists of five parallel long bones,^ whose heads articulate with 

 the toes, rough on each side, and whose bases articulate with each 

 of the three cuneiform and cuboid bones. The necks are narrow. 



First. On the inside of the foot; easily recognised, being the shorter 

 and thickest of the set. Its base is large and articulates with the in- 

 ternal cuneiform bone, and has a tubercle below for the peroneus 

 longus. The head is spherical, articulating with the first phalanx in 

 front, and below with the sesamoid bones. 



Second. Is the longest. Its base articulates with the middle cunei- 

 form, and on the inside with the internal cuneiform, and on the outside 

 with the third metatarsal and external cuneiform. 



Third. Is distinguished by the external surface of its base, having 

 two articular facets for the fourth metatarsal. The base articulates 

 also with the external cuneiform and second metatarsal. 



Fourth. Its base articulates with the cuboid, and on either side 

 with the contiguous metatarsal bone. The internal lateral face of 

 the bone is distinguished by having two articular marks. 



Fifth. Is the smallest and readily recognised by the large tubercle 

 projecting backwards and outwards from the base, into the superior 

 part of which is inserted the peroneus fortius, and into the extremity 

 the peroneus brevis. This process is a surgical guide in Hey's am- 

 putation of the foot. The base articulates with the cuboid and fourth 

 metatarsal. 



