32 



THE ANATOMY OF VEETEBEATED ANIMALS. 



the corresponding bones in the carpus, the fourth and fifth 

 tarsalia have coalesced to form the cuboides. 



Fig. 11. 



Fig. 11. — The right forefoot of the Chelonian Clielt/dra, and the rigiit 

 hind-foot of the Amphibian Salamandra. — U. ulna ; R. radius ; F. 

 fibula ; T. tibia. 



Proximal carpal bones: r. radiale ; i. intermedium ; «. ulnars ; the 

 centrale is the middle unlettered bone. 



Proximal tarsal bones : t. tibiale ; i. intermedium ; /. fibulare ; c. cen- 

 trale ; 1, 2, 3, 4, 5, distal carpalia and tarsalia; i, ii, iii, iv, v, 

 digits. 



The Position of the Limbs. — In their primitive position, 

 the limbs are straight, and are directed outwards, at right 

 angles to the axis of the body ; but, as development pro- 

 ceeds, they become bent in such a manner that, in the 

 first place, the middle division of each limb is flexed down- 

 wards and towards the middle line, upon the proximal divi- 

 sion ; while the distal division takes an opposite bend upon 

 the middle division. Thus the ventral aspects of the ante- 

 brachium and cms come to look inwardly, and the dorsal 

 aspects outwardly; while the ventral aspects of the nmnus 

 and pes look downwards, and their dorsal aspects look up- 

 wards. When the position of the limbs has been no further 



