484 



EXTREMITIES OF LOWER ANIMALS. 



stances, we find the number of bones in the hand increased, 

 but all of them enclosed in one envelope, so that the fingers 

 are not separate. This is the case with many aquatic animals 



Fig. 229. SKELETON OF THE CAMEL. 



vc, cervical vertebrae ; v d, dorsal vertebrae ; vl, lumbar vertebras ; vs. sacral vertebrae ; 

 vq, caudal vertebras; s, scapula; h, humerus; cu, ulna; ca, carpus; me, meta- 

 carpus ; ph, phalanges ; fe, femur ; ro, patella ; ti, tibia ; ta, tarsus ; nut, metatarsus. 



such as the Whale tribe among Mammals, Turtles among 

 Reptiles, and Fishes in general, in which the hand is made 

 to serve as a fin or paddle. In most of these, the bones of 

 the arm are very short ; and the movements of the extremity 

 are chiefly confined to the wrist-joint. 



645. The structure of the lower extremities has a very great 

 analogy to that of the upper \ and the principal differences to 

 be remarked between them, are such as are necessary to give 

 to the former more solidity at the expense of freedom of 

 motion, and to make them organs of locomotion instead of 

 organs of prehension. Here, too, we have a bony framework, 

 for the purpose of connecting the limb itself with the spine ; 

 and as the weight of the body is constantly thrown upon the 



