124 Ernes cf the Foot . [Book IX. 



The foot is compofed of the bones of the tarfus. 

 metatarfus, and toes. It is convex above, concave 

 below, and has a confiderable projection behind. 



The tarfus, which is connected with the bones of 

 the leg, confifts of feven pieces of bone, the aftragalus, 

 the os calcis, the os naviculare, the os cuboideum, 

 and the three ofla cuneiformia. The aftragulus occu- 

 pies the pofterior and upper part of the foot, and is 

 the bone on which the bones of the leg immediately 

 depend for fupport. The os calcis forms the pro- 

 jection of the heel ; it is of a very irregular form, and 

 is divided into the body, which points backwards, and 

 an anterior procefs by which it is connected with the 

 aftragalus and the os cuboideum. The os naviculare 

 is placed before the aftragalus, and towards the infide 

 of the foot ; it derives its name from its fuppofed re- 

 femblance to a boat. The os cuboideum is placed 

 before the os calcis, and towards the outfide of the 

 foot. The three offa cuneiformia are placed before 

 the os naviculare, near to tach other, and are fo called 

 from their appearing like wedges driven in among the 

 other bones of the foot. The fubftance of the offa 

 tirfi is fpongy, and they are fo connected together by 

 cartilage as not to admit of much motion upoa each 

 other. 



The metatarfus confifts of five cylindrical pieces of 

 bone, interpofed between the tarfus and the bones of 

 the toes. Their upper furface is convex, their lower 

 furfacc concave ; their pofterior extremity is concave 

 where they are connected with the tarfus, and their an- 

 terior extremity is furnifhed with condyls, by which 

 they are fafteued to the bones of the toes. 



The bones of the tees are connected to" thofe of the 

 metatarfus. The great toe has only two joints, the reft 

 three, and in this refpedt they referable the fingers and 



the 



