320 COMPARATIVE ANATOMY AND PHYSIOLOGY. 



The importance of the vertebral column is well 

 illustrated by the arrangements which obtain in the 



Fig. 133. Skeleton and Carapace of the Loggerheaded Turtle 

 (from below). 



Mammalia. We find that not only does the bony tube 

 afford a complete defence for the enclosed spinal cord, 

 and that the several parts of which it is composed can 

 be bent on one another, but that it is elastic in virtue 



