THE HIND-LIMB. 333 



with a facet on the outer surface of the head 

 of the tibia. , 



Its distal portion is completely fused with 

 the tibia, and bears at its end an articular 

 surface for the calcaneum. 



The tarsus (fig. 63) consists, in the rabbit, of six bones, 

 arranged, like the bones of the wrist, in a proximal 

 and a distal row, with a central bone between them. 

 The typical tarsus exactly corresponds to the typical 

 carpus in number and arrangement of bones. 



a. The proximal row of tarsals consists of two bones, 

 i. The astragalus, which probably corresponds to 



the tibiale and intermedium of the typical 

 tarsus fused together, lies on the inner or 

 preaxial side of the tarsus : it articulates by a 

 prominent pulley-like surface with the distal 

 end of the tibia. 



ii. The calcaneum, or fibulare, is the largest bone 

 of the tarsus : it lies along the outer side of 

 the astragalus, articulating with the fibula, 

 and is produced backwards into the large 

 calcaneal process or heel. 



b. The central bone. 



The naviculare, or centrale, is placed immedi- 

 ately in front of the astragalus. It sends 

 forwards a large process along the ventral 

 surface of the foot. 



c. The distal row of tarsals consists of three bones, the 



innermost or preaxial bone of the typical tarsus 

 being absent, together with the digit which it 

 supports, though probably represented by the 

 process at the proximal end of the second meta- 

 tarsal ; while the two outer tarsalia, like the 

 corresponding carpalia, fuse together. 



i. The second tarsale, or meso-cuneiform, is very 



AA* 



