238 ZOOTOMY. 



115. The patella, a small nodule of bone in front of 

 the knee-joint, connected by ligament with the femur and 

 tibio-tarsus. 



116. The fibula, a slender bony rod attached to the outer 

 (post-axial) side of the tibio-tarsus : its proximal end articu- 

 lates with the fibular fossa in the outer condyle of the femur : 

 distally it undergoes a gradual diminution in diameter and 

 finally fuses with the tibio-tarsus. 



117. The tarso-metarsus, a cylindrical bone articulated 

 to the distal end of the tibio-tarsus, its proximal end bearing 

 two concave surfaces for the condyles of the latter bone : 

 behind (ventrally) it is produced at its proximal end into a 

 strong crest, on either side of which is a small foramen 

 passing through to the somewhat concave anterior face of 

 the bone : its distal end is trifurcate, the middle division 

 being the longest, and each bearing a pulley-like surface 

 for the articulation of one of the toes. That part of the 

 tarso-metatarsus which lies above (proximal to) the two 

 foramina represents the distal tarsals : in the remainder of 

 the bone, the two foramina and trifurcate distal ends indicate 

 a division into three longitudinal parts, the second, third, 

 and fourth metatarsals. The joint between the tibio- 

 tarsus and tarso-metatarsus is conveniently known as the 

 mesotarsal articulation, being between the proximal 

 and distal tarsals. 



118. In an embryo towards the end of incubation, the 

 proximal extremity of the future tarso-metatarsus is a 

 separate cartilage, the distal tarsal cartilage (Fig. 51, 

 //.2)and the remainder is formed of three separate long 

 bones, (metatarsals, mtl.2^ mtl.T,, mtl./^), inclose contact save 

 at their distal ends. 



119. The hallux, or first pre-axial digit, consisting of a 

 separate metatarsal, united by ligament to the inner border 



